Tazarotene-induced gene 1(TIG1)is induced by a derivative of vitamin A and is known to regulate many important biological processes and control the development of cancer.TIG1 is widely expressed in various tissues;yet...Tazarotene-induced gene 1(TIG1)is induced by a derivative of vitamin A and is known to regulate many important biological processes and control the development of cancer.TIG1 is widely expressed in various tissues;yet in many cancer tissues,it is not expressed because of the methylation of its promoter.Additionally,the expression of TIG1 in cancer cells inhibits their growth and invasion,suggesting that TIG1 acts as a tumor suppressor gene.However,in some cancers,poor prognosis is associated with TIG1 expression,indicating its protumor growth characteristics,especially in promoting the invasion of inflammatory breast cancer cells.This review comprehensively summarizes the roles of the TIG1 gene in cancer development and details the mechanisms through which TIG1 regulates cancer development,with the aim of understanding its various roles in cancer development.展开更多
A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, en...A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, encoding a protein of 219 amino acids with 46 basic amino acids, leading to a high isoelectric point of 11.02. Homology search showed that this gene existed in eukaryotes and highly conserved throughout eukaryotes, suggesting an essential role of this gene. Northern Not analysis showed that it was expressed in various rice organs, but at lower level in developing flower and callus tissue than in other vegetative organs. Its expression levels in roots and leaves were influenced by different environmental factors.展开更多
Objective:To discuss the relationship of ultrasonic shear wave velocity (SWV) with oncogene and tumor suppressor gene expression in primary liver cancer lesions as well as angiogenesis factor contents.Methods:100 pati...Objective:To discuss the relationship of ultrasonic shear wave velocity (SWV) with oncogene and tumor suppressor gene expression in primary liver cancer lesions as well as angiogenesis factor contents.Methods:100 patients with primary liver cancer who underwent surgical treatment in our hospital between March 2014 and September 2016 were collected as observation group, and 50 healthy subjects who received physical examination in our hospital during the same period were collected as normal control group. The ultrasonic SWV levels of two groups of subjects were measured before the operation, and the observation groups were further divided into high SWV group and low SWV group, 50 cases in each group. Intraoperative tumor tissue samples were kept and fluorescence quantitative PCR was used to determine the mRNA expression of oncogenes and tumor suppressor genes. Enzyme-linked immunosorbent assay was used to determine serum contents of angiogenesis factors in observation group before operation.Results:Hepatic ultrasonic SWV level in observation group was significantly higher than that in normal control group;proto-oncogene CK, Ki67, Gly-3, Survivin and Pokemon mRNA expression in tumor tissue of high SWV group were higher than those of low SWV group while tumor suppressor genes Tg737, p16, p27, PTEN and runx3 mRNA expression were lower than those of low SWV group;serum angiogenesis factors VEGF, MMP-9 and IGF-1R contents were higher than those in low SWV group. Conclusion: The hepatic ultrasonic SWV level increases in patients with primary liver cancer, and the SWV level is directly correlated with oncogene and tumor suppressor gene expression as well as angiogenesis factor contents.展开更多
Stomach adenocarcinoma (STAD) is the fifth most prevalent cancer and the third leading cause of cancer-related death in the world and is more common in Asia than in most Western countries. There is an urgent need to i...Stomach adenocarcinoma (STAD) is the fifth most prevalent cancer and the third leading cause of cancer-related death in the world and is more common in Asia than in most Western countries. There is an urgent need to identify potential novel oncogenes and tumor suppressor genes, and biomarkers for STAD. 6652 differentially expressed genes were identified between STAD and normal samples based on the transcriptome data analysis of the TCGA and GEO databases. 13 key modules were identified in STAD by WGCNA analysis. 293 potential STAD associated genes were identified from intersection by Venn Diagram. The 293 intersected genes were enriched in cell cortex and infection by GO and KEGG analysis. 10 hub genes were identified from PPI and Cytoscape analyses of the intersected genes. KLF4/CGN low and SHH/LIF high expression were associated with short overall survival of Asian STAD patients. Bioinformatics analysis revealed potential novel tumor suppressors (KLF4/CGN), oncogenes (SHH/LIF) and biomarkers for diagnosis, therapy and prognosis of STAD, specifically for Asian patients.展开更多
Atypical teratoid/rhabdoid tumor(ATRT)is a rare childhood malignancy that originates in the central nervous system.Over ninety-five percent of ATRT patients have biallelic inactivation of the tumor suppressor gene SMA...Atypical teratoid/rhabdoid tumor(ATRT)is a rare childhood malignancy that originates in the central nervous system.Over ninety-five percent of ATRT patients have biallelic inactivation of the tumor suppressor gene SMARCB1.ATRT has no standard treatment,and a major limiting factor in therapeutic development is the lack of reliable ATRT models.We employed CRISPR/Cas9 gene-editing technology to knock out SMARCB1 and TP53 genes in human episomal induced pluripotent stem cells(Epi-iPSCs),followed by brief neural induction,to generate an ATRT-like model.The dual knockout Epi-iPSCs retained their stemness with the capacity to differentiate into three germ layers.High expression of OCT4 and NANOG in neurally induced knockout spheroids was comparable to that in two ATRT cell lines.Beta-catenin protein expression was higher in SMARCB1-deficient cells and spheroids than in normal Epi-iPSC-derived spheroids.Nucleophosmin,Osteopontin,and Ki-67 proteins were also expressed by the SMARCB1-deficient spheroids.In summary,the tumor model resembled embryonal features of ATRT and expressed ATRT biomarkers at mRNA and protein levels.Ribociclib,PTC-209,and the combination of clofilium tosylate and pazopanib decreased the viability of the ATRT-like cells.This disease modeling scheme may enable the establishment of individualized tumor models with patient-specific mutations and facilitate high-throughput drug testing.展开更多
Objective: To detect the aberrant methylation patterns in the CpG islands of p16 and p15 tumor suppressor genes, and to analyze its correlation with pancreatic carcinogenesis and with clinicopathological characterist...Objective: To detect the aberrant methylation patterns in the CpG islands of p16 and p15 tumor suppressor genes, and to analyze its correlation with pancreatic carcinogenesis and with clinicopathological characteristics of patients with pancreatic cancer (PC). Methods: The methylation-specific polymerase chain reaction (MSP) method was used to monitor methylation patterns in the CpG islands of p15 and p16 genes from 29 cases of PC and 3 cases of chronic pancreatitis (CP) paraffin-embedded tissue, as well as 2 cases of normal liver tissues and 12 cases of normal blood samples. Results: p15 and p16 genes were detected to show unmethylation patterns and no amplification using methylation-specific primers in control group. The aberrant methylation rates of p16 in carcinoma tissue and adjacent noncarcinoma tissue were 37.9% (11 of 29 cases) and 34.5% (10 of 29 cases) respectively. Of the 11 aberrant methylated samples, 5 showed complete methylation and 6 hemimethylation. The methylation rates of p15 gene in carcinoma tissue and adjacent noncarcinoma tissue were 27.5% (8/29) and 24.4% (7/29) respectively. Of the 8 aberrant methylated samples, 3 showed complete methylation and 5 hemimethylation. In 6 PC samples, aberrant methylation in CpG islands of both p15 and p16 genes existed simultaneously. The aberrant methylation patterns in CpG islands of p15 and p16 genes had no close correlation with the clinicopathological characteristics (age, sex, smoking, volume of primary tumor, differentiation, clinical stage and histological classification) of the patients with PC (P〉0.05). Conclusion: The aberrant methylation in CpG islands of p15 and p16 genes could be regarded as an early molecular event in PC and had no close correlation with the clinicopathological characteristics of the patients with PC.展开更多
IM To study the alterations of tumor suppressor gene p16 and Rb in the carcinogenesis of the stomach. METHODS Different mucosal biopsies were endoscopically obtained, all samples were immediately fixed with 10% bu...IM To study the alterations of tumor suppressor gene p16 and Rb in the carcinogenesis of the stomach. METHODS Different mucosal biopsies were endoscopically obtained, all samples were immediately fixed with 10% buffered formalin, embedded with paraffin and sectioned serielly. Alterations of p16 and Rb protein in 12 cases of superficial gastritis, 15 atrophic gastritis, 20 atypical hyperplasia and 40 cancerous tissues were detected by the immunohistochemical method (ABC). RESULTS Different degrees of nuclear immunostaining of p16 and Rb occurred on gastric epithelium in different stages of lesions. With the lesions progressing, the positive immunostaining rate of p16 protein had a decreasing tendency (833%→733%→300%→275%), and on the other hand, that of Rb protein had an increasing tendency (250%→467%→600%→675%). A negative correlationship was found between these two parameters in the gastric cancer. Of 40 cases of gastric cancer, a negative relationship was observed in 20 cases. In comparison with both positive (9 cases) and both negative tissues (11 cases), there was a significant difference (500%,225%,275%) (P<005).CONCLUSION Abnormal expression of p16 and Rb plays an important role in gastric carcinogenesis.展开更多
AIM: To evaluate the genetic and epigenetic inactivation mechanism of the RASSF1A tumor suppressor gene at 3p21.3 in extrahepatic cholangiocarcinoma. METHODS: RT-PCR was used to investigate the transcriptional express...AIM: To evaluate the genetic and epigenetic inactivation mechanism of the RASSF1A tumor suppressor gene at 3p21.3 in extrahepatic cholangiocarcinoma. METHODS: RT-PCR was used to investigate the transcriptional expressing and re-expression of RASSFIA. RASSFIA mutation was analyzed with SSCP and selective sequencing. PCR was performed to detect the loss of heterozygosity (LOH) at the region of chromosome 3p21.3. Genomic DNA were modificated bisulfite and the frequency of methylation of CpG islands in RASSFIA promoter were evaluated by methylation specific PCR (MS-PCR). RESULTS: In all 48 samples and one cell lines of extrahepatic cholangiocarcinoma, the RASSFIA mutation is rare (6.12%, 3/49), 33 samples (68.75%) and QBC-939 cell lines (X2= 14.270, P= 0.001<0.01) showed RASSFIA express inactivation with LOH at microsatellite loci D3S4604. Among these 33 samples and QBC-939, 28 of 33 (84.85%) tumor samples and 1 cell lines were methylated for majority of 16 CpGs, the average frequency is 73.42%. CONCLUSION: The data we present suggest that RASSFIA which we have been searching for at 3p21.3 may be one of the key tumor suppressor gene and play an important role in the pathogenesis of extrahepatic cholangiocarcinoma, and the promoter methylation and allelic loss are the major mechanism for inactivation of RASSFIA.展开更多
AIM:To identify the novel methylation-silenced gene pentraxin 3(PTX3) in esophageal squamous cell carcinoma(ESCC).METHODS:PTX3 mRNA expression was examined in six human ESCC cell lines,one human immortalized normal es...AIM:To identify the novel methylation-silenced gene pentraxin 3(PTX3) in esophageal squamous cell carcinoma(ESCC).METHODS:PTX3 mRNA expression was examined in six human ESCC cell lines,one human immortalized normal esophageal epithelial cell line,primary ESCC tumor tissue,and paired adjacent nontumor tissue using reverse transcription polymerase chain reaction(RTPCR).Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels.Methylation specific PCR and bisulphite genomic sequencing were employed to investigate the methylation of the candidate gene.RESULTS:In the majority of ESCC cell lines,we found that PTX3 expression was down-regulated due to gene promoter hypermethylation,which was further confirmed by bisulphite genomic sequencing.Demethylation treatment with 5-aza-2'-deoxycytidine restored PTX3 mRNA expression in ESCC cell lines.Methylation was more common in tumor tissues(85%) than in adjacent nontumor tissues(25%)(P < 0.01).CONCLUSION:PTX3 is down-regulated through promoter hypermethylation in ESCC,and could potentially serve as a biomarker of ESCC.展开更多
Objective: Oncogenes have been shown to be drivers of non-small cell lung cancer(NSCLC), yet the tumor suppressing genes involved in lung carcinogenesis remain to be systematically investigated. This study aimed to id...Objective: Oncogenes have been shown to be drivers of non-small cell lung cancer(NSCLC), yet the tumor suppressing genes involved in lung carcinogenesis remain to be systematically investigated. This study aimed to identify tumor suppressing ubiquitin pathway genes(UPGs) that were critical to lung tumorigenesis.Methods: The 696 UPGs were silenced by an siRNA screening in NSCLC cells;the potential tumor suppressing UPGs were analyzed, and their clinical significance was investigated.Results: We reported that silencing of 11 UPGs resulted in enhanced proliferation of NSCLC cells, and four UPGs(UBL3, TRIM22, UBE2 G2, and MARCH1) were significantly downregulated in tumor samples compared to that in normal lung tissues and their expression levels were positively associated with overall survival(OS) of NSCLC patients. Among these genes, UBL3 was the most significant one. UBL3 expression was decreased in tumor samples compared to that in paired normal lung tissues in 59/86(68.6%) NSCLCs, was correlated with TNM stage and sex of NSCLC patients, and was significantly higher in non-smoking patients than in smoking patients. Silencing UBL3 accelerated cell proliferation and ectopic expression of UBL3 suppressed NSCLC in vitro and in vivo.Conclusions: These results showed that UBL3 represented a tumor suppressor in NSCLC and may have potential for use in therapeutics and for the prediction of clinical outcome of patients.展开更多
Objective YAP1 plays a dual role as an oncogene and tumor suppressor gene in several tumors;differentiating between these roles may depend on the YAP1 phosphorylation pattern.The specific function of YAP1 in B cell ac...Objective YAP1 plays a dual role as an oncogene and tumor suppressor gene in several tumors;differentiating between these roles may depend on the YAP1 phosphorylation pattern.The specific function of YAP1 in B cell acute lymphoblastic leukemia(B-ALL),however,is currently unclear.Thus,in the present study,the role of YAP1 in B-ALL was investigated using relevant cell lines and patient datasets.Methods The effects of shRNA-mediated knockdown on YAP1 and LATS1 levels in the NALM6 and MOLT-4 cell lines were examined using Western blotting,quantitative real-time polymerase chain reaction,flow cytometry,immunostaining,and nude mouse subcutaneous tumorigenesis experiments.Gene expression levels of Hippo pathway-related molecules before and after verteporfin(VP)treatment were compared using RNA-Seq to identify significant Hippo pathway-related genes in NALM6 cells.Results Patients with ALL showing high YAP1 expression and low YAP1-Ser127 phosphorylation levels had worse prognoses than those with low YAP1 protein expression and high YAP1-Ser127 phosphorylation levels.YAP1-Ser127 phosphorylation levels were lower in NALM6 cells than in MOLT-4 and control cells;YAP1 was distributed in the nuclei in NALM6 cells.Knockdown of YAP1 inhibited MOLT-4 and NALM6 cell proliferation and arrested the NALM6 cell cycle in the G0/G1 phase.Before and after VP treatment,the expression of the upstream gene LATS1 was upregulated;its overexpression promoted YAP1-Ser127 phosphorylation.Further,YAP1 was distributed in the plasma.Conclusion LATS1 may downregulate YAP1-Ser127 phosphorylation and maintain B-ALL cell function;thus,VP,which targets this axis,may serve as a new therapeutic method for improving the outcomes for B-ALL patients.展开更多
AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors....AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.展开更多
Background:Lung adenocarcinoma is a very pervasive histological form of lung cancers,and inhibiting metastasis is crucial for effective treatment.In this investigation,we explored the functional interaction of miR-30a...Background:Lung adenocarcinoma is a very pervasive histological form of lung cancers,and inhibiting metastasis is crucial for effective treatment.In this investigation,we explored the functional interaction of miR-30a-5p and the putative transcription factor 2 of the homeodomain(PHTF2)in dictating the aggressiveness and metastasis of lung adenocarcinoma.Method:We collected clinical samples to evaluate the expression patterns of miR-30a-5p and PHTF2 in lung adenocarcinoma along with normal tissues.Cellular experiments including cell count kit(CCK)-8 growth assay,apoptosis analysis,migration and invasion examinations were performed to assess the aggressiveness of lung adenocarcinoma cells.Furthermore,we examined tumorigenesis and metastasis in a nude mouse model.Results:MiR-30a-5p exhibited downregulation pattern in lung adenocarcinoma samples.Transfection of miR-30a-5p mimic in lung adenocarcinoma cells resulted in the suppression of malignant characteristics.Notably,the administration of miR-30a-5p mimic also curbed tumorigenesis and metastasis of lung adenocarcinoma cells in animal model.Moreover,PHTF2 was found to be a molecular target of miR-30a-5p.Upregulating PHTF2 counteracted the tumor-suppressive effect of the miR-30a-5p mimic.Conclusion:miR-30a-5p functions as a tumor-suppressive molecule while PHTF2 acts as an oncogenic factor in the development and metastasis of lung adenocarcinoma.Therefore,targeting miR-30a-5p and PHTF2 could be developed into a promising therapeutic approach for inhibiting metastasis in lung adenocarcinoma.展开更多
BACKGROUND Hepatocellular carcinoma(HCC)is a major cause of cancer mortality worldwide,and metastasis is the main cause of early recurrence and poor prognosis.However,the mechanism of metastasis remains poorly underst...BACKGROUND Hepatocellular carcinoma(HCC)is a major cause of cancer mortality worldwide,and metastasis is the main cause of early recurrence and poor prognosis.However,the mechanism of metastasis remains poorly understood.AIM To determine the possible mechanism affecting HCC metastasis and provide a possible theoretical basis for HCC treatment.METHODS The candidate molecule lecithin-cholesterol acyltransferase(LCAT)was screened by gene microarray and bioinformatics analysis.The expression levels of LCAT in clinical cohort samples was detected by quantitative realtime polymerase chain reaction and western blotting.The proliferation,migration,invasion and tumor-forming ability were measured by Cell Counting Kit-8,Transwell cell migration,invasion,and clonal formation assays,respectively.Tumor formation was detected in nude mice after LCAT gene knockdown or overexpression.The immunohistochemistry for Ki67,E-cadherin,N-cadherin,matrix metalloproteinase 9 and vascular endothelial growth factor were performed in liver tissues to assess the effect of LCAT on HCC.Gene set enrichment analysis(GSEA)on various gene signatures were analyzed with GSEA version 3.0.Three machine-learning algorithms(random forest,support vector machine,and logistic regression)were applied to predict HCC metastasis in The Cancer Genome Atlas and GEO databases.RESULTS LCAT was identified as a novel gene relating to HCC metastasis by using gene microarray in HCC tissues.LCAT was significantly downregulated in HCC tissues,which is correlated with recurrence,metastasis and poor outcome of HCC patients.Functional analysis indicated that LCAT inhibited HCC cell proliferation,migration and invasion both in vitro and in vivo.Clinicopathological data showed that LCAT was negatively associated with HCC size and metastasis(HCC size≤3 cm vs 3-9 cm,P<0.001;3-9 cm vs>9 cm,P<0.01;metastatic-free HCC vs extrahepatic metastatic HCC,P<0.05).LCAT suppressed the growth,migration and invasion of HCC cell lines via PI3K/AKT/mTOR signaling.Our results indicated that the logistic regression model based on LCAT,TNM stage and the serum level of α-fetoprotein in HCC patients could effectively predict high metastatic risk HCC patients.CONCLUSION LCAT is downregulated at translational and protein levels in HCC and might inhibit tumor metastasis via attenuating PI3K/AKT/mTOR signaling.LCAT is a prognostic marker and potential therapeutic target for HCC.展开更多
Objective: To investigate whether deletion of chromosome 3 is involved in the carcinogenesis of primary glioblastoma multiforme (GBM) and to localize the possible common deletion region in the aforementioned chromosom...Objective: To investigate whether deletion of chromosome 3 is involved in the carcinogenesis of primary glioblastoma multiforme (GBM) and to localize the possible common deletion region in the aforementioned chromosome. Methods: PCR based microsatellite polymorphism analyses were performed to detect loss of heterozygosity (LOH). Twenty-three loci on chromosome 3 were examined in 20 cases of GBM. Fluorescence-labeled primers and Perkin Elmer 377 DNA Sequencer were applied. Results: 50% informative cases of GBM displayed LOH on chromosome 3. 50% of informative cases displayed LOH on 3q and 35% on 3p. 25.6% of informative loci showed LOH in our series, in which frequent LOH were observed in the chromosomal region from loci D3S1614 (42.9%) to D3S1565 (35.3%) on 3q24–27 and at loci D3S1569 (35.3%) on 3q22–23 and D3S1289 (33.3%) on 3p14.1–14.3. Conclusion: Loss of genetic material on chromosome 3 may play an important part in the tumorigenesis of GBM. The chromosomal regions from loci D3S1614 to D3S1565 on 3q24–27 and at loci D3S1569 on 3q22–23 and D3S1289 on 3p14.1–14.3 are potential sites for novel tumor suppressor genes associated with GBM.展开更多
Objective: To investigate whether deletion of chromosome 17 is involved in the carcinogenesis of primary glioblastoma multiforme and to localize the possible common deletion region in the aforementioned chromosome. Me...Objective: To investigate whether deletion of chromosome 17 is involved in the carcinogenesis of primary glioblastoma multiforme and to localize the possible common deletion region in the aforementioned chromosome. Methods: Polymerase chain reaction-based microsatellite analysis was used to assess loss of heterozygosity (LOH) on chromosome 17 in 20 primary glioblastoma multiforme (GBM). Fifteen fluorescent dye-labeled polymorphic markers were used. Results: Thirteen of twenty (65%) GBM displayed LOH on at least one marker of chromosome 17p. Two tumors showed either LOH or non-informativeness on all markers tested. The most frequent LOH was observed at loci including D17s799 (53.3%), D17s1852 (53.8%), D17s938 (63.20/o), D17s831 (55.6%). The loci D17s831 (on 17p13) and D17s799–D17s1852 (17p11.2–p12) are distal and proximal to p53 respectively. The frequencies of LOH at all loci examined on chromosome 17q were relatively low (<30%). None of informative loci exhibited microsatellite instability in this study. Conclusion: Loss of genetic material on chromosome 17p may play an important role in the pathogenesis of GBM. Besides the well-known TSG p53 on 17p, other unknown TSCs associated with GBM may be present on the chromosomal regions 17p13 and 17p11.2–p12, which are distal and proximal to p53 respectively.展开更多
Data obtained in experimental cutaneous melanomas have suggested that the nm23 gene may function as a metastasis suppressor gene. The nm23 level in 8 human cutaneous melanoma cell lines and 2 murine melanoma cell line...Data obtained in experimental cutaneous melanomas have suggested that the nm23 gene may function as a metastasis suppressor gene. The nm23 level in 8 human cutaneous melanoma cell lines and 2 murine melanoma cell lines were examined. Each melanoma cell line was transplanted subcutaneously into the flank of nude mice, and the metastatic behavior was evaluated by counting lung tumor fool and by determining host survival time. It was found that expression of 'm23 mRNA in human melanomas is correlated closely with reduced metastatic behavior in experimental animals and may serve as a sensitive prognostic indicator of malignancy and survival in patients with melanomas.展开更多
AIM: To study the candidate tumor suppressor genes (TSG) on chromosome 4p by detecting the high frequency of loss of heterozygosity (LOH) in sporadic colorectal carcinoma in Chinese patients.METHODS: Seven fluorescent...AIM: To study the candidate tumor suppressor genes (TSG) on chromosome 4p by detecting the high frequency of loss of heterozygosity (LOH) in sporadic colorectal carcinoma in Chinese patients.METHODS: Seven fluorescent labeled polymorphic microsatellite markers were analyzed in 83 cases of colorectal carcinoma and matched normal tissue DNA by PCR. PCR products were eletrophoresed on an ABI 377 DNA sequencer. Genescan 3.7 and Genotype 3.7 software were used for LOH scanning and analysis. The same procedure was performed by the other six microsatellite markers spanning D4S3013 locus to make further detailed deletion mapping. Comparison between LOH frequency and clinicopathological factors was performed by χ2 test.RESULTS: Data were collected from all informative loci. The average LOH frequency on 4p was 24.25%, and 42.3% and 35.62% on D4S405 and D4S3013 locus, respectively. Adjacent markers of D4S3013 displayed a low LOH frequency (< 30%) by detailed deletion mapping. Significant opposite difference was observed between LOH frequency and tumor diameter on D4S412 and D4S1546 locus (0% vs 16.67%, P = 0.041; 54.55% vs 11.11%, P = 0.034, respectively). On D4S403 locus, LOH was significantly associated with tumor gross pattern (11.11%, 0, 33.33%, P = 0.030). No relationship was detected on other loci compared with clinicopathologial features.CONCLUSION: By deletion mapping, two obvious high frequency LOH regions spanning D4S3013 (4p15.2) and D4S405 (4p14) locus are detected. Candidate TSG, which is involved in carcinogenesis and progression of sporadic colorectal carcinoma on chromosome 4p, may be located between D4S3017 and D4S2933 (about 1.7 cm).展开更多
Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 pati...Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 patients with primary colon cancer were enrolled in colon cancer group, 68 patients with benign colon polyps were enrolled in colon polyps group, the differences in the expression levels of RunX2, proliferation genes, tumor suppressor genes and angiogenesis molecules in the two groups of lesions were compared, and Pearson test was further used to evaluate the correlation of RunX2 expression level with proliferation gene, tumor suppressor gene and angiogenesis molecule expression levels in colon cancer tissues. Results: RunX2 mRNA expression level in the lesions of colon cancer group was higher than that of colon polyps group. Proliferation genes GTPBP4, HOXB7, ZNF331, ADAM17 and HSP60 mRNA expression levels in the lesions of colon cancer group were higher than those of colon polyps group;tumor suppressor genes ATF3, FOXN3, OTUD1 and NDRG2 mRNA expression levels were lower than those of colon polyps group;angiogenesis molecules Musashi 1, NF-κB, RegⅣ and STAT3 mRNA expression levels were higher than those of colon polyps group. RunX2 mRNA expression level in the colon cancer lesions was directly correlated with the expression levels of the above proliferation genes, tumor suppressor genes and angiogenesis molecules. Conclusion: RunX2 expression is abnormally high in colon cancer lesions, the specific expression level is positively correlated with cancer cell proliferation activity and angiogenesis activity, and it is an important molecular target that can lead to the occurrence and development of colon cancer.展开更多
基金supported by the Taipei Tzu Chi Hospital through grants from the Buddhist Tzu Chi Medical Foundation under the Numbers TCRD-TPE-111-23(2/3)and TCRD-TPE-113-20,Taipei,Taiwan.
文摘Tazarotene-induced gene 1(TIG1)is induced by a derivative of vitamin A and is known to regulate many important biological processes and control the development of cancer.TIG1 is widely expressed in various tissues;yet in many cancer tissues,it is not expressed because of the methylation of its promoter.Additionally,the expression of TIG1 in cancer cells inhibits their growth and invasion,suggesting that TIG1 acts as a tumor suppressor gene.However,in some cancers,poor prognosis is associated with TIG1 expression,indicating its protumor growth characteristics,especially in promoting the invasion of inflammatory breast cancer cells.This review comprehensively summarizes the roles of the TIG1 gene in cancer development and details the mechanisms through which TIG1 regulates cancer development,with the aim of understanding its various roles in cancer development.
文摘A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, encoding a protein of 219 amino acids with 46 basic amino acids, leading to a high isoelectric point of 11.02. Homology search showed that this gene existed in eukaryotes and highly conserved throughout eukaryotes, suggesting an essential role of this gene. Northern Not analysis showed that it was expressed in various rice organs, but at lower level in developing flower and callus tissue than in other vegetative organs. Its expression levels in roots and leaves were influenced by different environmental factors.
基金Natural Science Foundation of China No:81170108.
文摘Objective:To discuss the relationship of ultrasonic shear wave velocity (SWV) with oncogene and tumor suppressor gene expression in primary liver cancer lesions as well as angiogenesis factor contents.Methods:100 patients with primary liver cancer who underwent surgical treatment in our hospital between March 2014 and September 2016 were collected as observation group, and 50 healthy subjects who received physical examination in our hospital during the same period were collected as normal control group. The ultrasonic SWV levels of two groups of subjects were measured before the operation, and the observation groups were further divided into high SWV group and low SWV group, 50 cases in each group. Intraoperative tumor tissue samples were kept and fluorescence quantitative PCR was used to determine the mRNA expression of oncogenes and tumor suppressor genes. Enzyme-linked immunosorbent assay was used to determine serum contents of angiogenesis factors in observation group before operation.Results:Hepatic ultrasonic SWV level in observation group was significantly higher than that in normal control group;proto-oncogene CK, Ki67, Gly-3, Survivin and Pokemon mRNA expression in tumor tissue of high SWV group were higher than those of low SWV group while tumor suppressor genes Tg737, p16, p27, PTEN and runx3 mRNA expression were lower than those of low SWV group;serum angiogenesis factors VEGF, MMP-9 and IGF-1R contents were higher than those in low SWV group. Conclusion: The hepatic ultrasonic SWV level increases in patients with primary liver cancer, and the SWV level is directly correlated with oncogene and tumor suppressor gene expression as well as angiogenesis factor contents.
文摘Stomach adenocarcinoma (STAD) is the fifth most prevalent cancer and the third leading cause of cancer-related death in the world and is more common in Asia than in most Western countries. There is an urgent need to identify potential novel oncogenes and tumor suppressor genes, and biomarkers for STAD. 6652 differentially expressed genes were identified between STAD and normal samples based on the transcriptome data analysis of the TCGA and GEO databases. 13 key modules were identified in STAD by WGCNA analysis. 293 potential STAD associated genes were identified from intersection by Venn Diagram. The 293 intersected genes were enriched in cell cortex and infection by GO and KEGG analysis. 10 hub genes were identified from PPI and Cytoscape analyses of the intersected genes. KLF4/CGN low and SHH/LIF high expression were associated with short overall survival of Asian STAD patients. Bioinformatics analysis revealed potential novel tumor suppressors (KLF4/CGN), oncogenes (SHH/LIF) and biomarkers for diagnosis, therapy and prognosis of STAD, specifically for Asian patients.
文摘Atypical teratoid/rhabdoid tumor(ATRT)is a rare childhood malignancy that originates in the central nervous system.Over ninety-five percent of ATRT patients have biallelic inactivation of the tumor suppressor gene SMARCB1.ATRT has no standard treatment,and a major limiting factor in therapeutic development is the lack of reliable ATRT models.We employed CRISPR/Cas9 gene-editing technology to knock out SMARCB1 and TP53 genes in human episomal induced pluripotent stem cells(Epi-iPSCs),followed by brief neural induction,to generate an ATRT-like model.The dual knockout Epi-iPSCs retained their stemness with the capacity to differentiate into three germ layers.High expression of OCT4 and NANOG in neurally induced knockout spheroids was comparable to that in two ATRT cell lines.Beta-catenin protein expression was higher in SMARCB1-deficient cells and spheroids than in normal Epi-iPSC-derived spheroids.Nucleophosmin,Osteopontin,and Ki-67 proteins were also expressed by the SMARCB1-deficient spheroids.In summary,the tumor model resembled embryonal features of ATRT and expressed ATRT biomarkers at mRNA and protein levels.Ribociclib,PTC-209,and the combination of clofilium tosylate and pazopanib decreased the viability of the ATRT-like cells.This disease modeling scheme may enable the establishment of individualized tumor models with patient-specific mutations and facilitate high-throughput drug testing.
文摘Objective: To detect the aberrant methylation patterns in the CpG islands of p16 and p15 tumor suppressor genes, and to analyze its correlation with pancreatic carcinogenesis and with clinicopathological characteristics of patients with pancreatic cancer (PC). Methods: The methylation-specific polymerase chain reaction (MSP) method was used to monitor methylation patterns in the CpG islands of p15 and p16 genes from 29 cases of PC and 3 cases of chronic pancreatitis (CP) paraffin-embedded tissue, as well as 2 cases of normal liver tissues and 12 cases of normal blood samples. Results: p15 and p16 genes were detected to show unmethylation patterns and no amplification using methylation-specific primers in control group. The aberrant methylation rates of p16 in carcinoma tissue and adjacent noncarcinoma tissue were 37.9% (11 of 29 cases) and 34.5% (10 of 29 cases) respectively. Of the 11 aberrant methylated samples, 5 showed complete methylation and 6 hemimethylation. The methylation rates of p15 gene in carcinoma tissue and adjacent noncarcinoma tissue were 27.5% (8/29) and 24.4% (7/29) respectively. Of the 8 aberrant methylated samples, 3 showed complete methylation and 5 hemimethylation. In 6 PC samples, aberrant methylation in CpG islands of both p15 and p16 genes existed simultaneously. The aberrant methylation patterns in CpG islands of p15 and p16 genes had no close correlation with the clinicopathological characteristics (age, sex, smoking, volume of primary tumor, differentiation, clinical stage and histological classification) of the patients with PC (P〉0.05). Conclusion: The aberrant methylation in CpG islands of p15 and p16 genes could be regarded as an early molecular event in PC and had no close correlation with the clinicopathological characteristics of the patients with PC.
文摘IM To study the alterations of tumor suppressor gene p16 and Rb in the carcinogenesis of the stomach. METHODS Different mucosal biopsies were endoscopically obtained, all samples were immediately fixed with 10% buffered formalin, embedded with paraffin and sectioned serielly. Alterations of p16 and Rb protein in 12 cases of superficial gastritis, 15 atrophic gastritis, 20 atypical hyperplasia and 40 cancerous tissues were detected by the immunohistochemical method (ABC). RESULTS Different degrees of nuclear immunostaining of p16 and Rb occurred on gastric epithelium in different stages of lesions. With the lesions progressing, the positive immunostaining rate of p16 protein had a decreasing tendency (833%→733%→300%→275%), and on the other hand, that of Rb protein had an increasing tendency (250%→467%→600%→675%). A negative correlationship was found between these two parameters in the gastric cancer. Of 40 cases of gastric cancer, a negative relationship was observed in 20 cases. In comparison with both positive (9 cases) and both negative tissues (11 cases), there was a significant difference (500%,225%,275%) (P<005).CONCLUSION Abnormal expression of p16 and Rb plays an important role in gastric carcinogenesis.
基金Supported by the National High Technology Research and Development Program of China (863 Program), No. 2002AA214061
文摘AIM: To evaluate the genetic and epigenetic inactivation mechanism of the RASSF1A tumor suppressor gene at 3p21.3 in extrahepatic cholangiocarcinoma. METHODS: RT-PCR was used to investigate the transcriptional expressing and re-expression of RASSFIA. RASSFIA mutation was analyzed with SSCP and selective sequencing. PCR was performed to detect the loss of heterozygosity (LOH) at the region of chromosome 3p21.3. Genomic DNA were modificated bisulfite and the frequency of methylation of CpG islands in RASSFIA promoter were evaluated by methylation specific PCR (MS-PCR). RESULTS: In all 48 samples and one cell lines of extrahepatic cholangiocarcinoma, the RASSFIA mutation is rare (6.12%, 3/49), 33 samples (68.75%) and QBC-939 cell lines (X2= 14.270, P= 0.001<0.01) showed RASSFIA express inactivation with LOH at microsatellite loci D3S4604. Among these 33 samples and QBC-939, 28 of 33 (84.85%) tumor samples and 1 cell lines were methylated for majority of 16 CpGs, the average frequency is 73.42%. CONCLUSION: The data we present suggest that RASSFIA which we have been searching for at 3p21.3 may be one of the key tumor suppressor gene and play an important role in the pathogenesis of extrahepatic cholangiocarcinoma, and the promoter methylation and allelic loss are the major mechanism for inactivation of RASSFIA.
基金Supported by National High Technology Research and Development Program of China (863 Program),No. 2007AA02Z4Z4China Postdoctoral Science Foundation,No. 20090460394Beijing Municipal Natural Science Foundation,No. 7072022
文摘AIM:To identify the novel methylation-silenced gene pentraxin 3(PTX3) in esophageal squamous cell carcinoma(ESCC).METHODS:PTX3 mRNA expression was examined in six human ESCC cell lines,one human immortalized normal esophageal epithelial cell line,primary ESCC tumor tissue,and paired adjacent nontumor tissue using reverse transcription polymerase chain reaction(RTPCR).Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels.Methylation specific PCR and bisulphite genomic sequencing were employed to investigate the methylation of the candidate gene.RESULTS:In the majority of ESCC cell lines,we found that PTX3 expression was down-regulated due to gene promoter hypermethylation,which was further confirmed by bisulphite genomic sequencing.Demethylation treatment with 5-aza-2'-deoxycytidine restored PTX3 mRNA expression in ESCC cell lines.Methylation was more common in tumor tissues(85%) than in adjacent nontumor tissues(25%)(P < 0.01).CONCLUSION:PTX3 is down-regulated through promoter hypermethylation in ESCC,and could potentially serve as a biomarker of ESCC.
基金supported by the National Key Research and Development Program of China (Grant No. 2016YFC0905501)the National Natural Science Funds for Distinguished Young Scholar (Grant No. 81425025)+3 种基金the Key Project of the National Natural Science Foundation of China (Grant No. 81830093)the CAMS Innovation Fund for Medical Sciences (Grant No. CIFMS2019-I2M-1-003)the National Natural Science Foundation of China (Grant No. 81672765 and 81802796)。
文摘Objective: Oncogenes have been shown to be drivers of non-small cell lung cancer(NSCLC), yet the tumor suppressing genes involved in lung carcinogenesis remain to be systematically investigated. This study aimed to identify tumor suppressing ubiquitin pathway genes(UPGs) that were critical to lung tumorigenesis.Methods: The 696 UPGs were silenced by an siRNA screening in NSCLC cells;the potential tumor suppressing UPGs were analyzed, and their clinical significance was investigated.Results: We reported that silencing of 11 UPGs resulted in enhanced proliferation of NSCLC cells, and four UPGs(UBL3, TRIM22, UBE2 G2, and MARCH1) were significantly downregulated in tumor samples compared to that in normal lung tissues and their expression levels were positively associated with overall survival(OS) of NSCLC patients. Among these genes, UBL3 was the most significant one. UBL3 expression was decreased in tumor samples compared to that in paired normal lung tissues in 59/86(68.6%) NSCLCs, was correlated with TNM stage and sex of NSCLC patients, and was significantly higher in non-smoking patients than in smoking patients. Silencing UBL3 accelerated cell proliferation and ectopic expression of UBL3 suppressed NSCLC in vitro and in vivo.Conclusions: These results showed that UBL3 represented a tumor suppressor in NSCLC and may have potential for use in therapeutics and for the prediction of clinical outcome of patients.
文摘Objective YAP1 plays a dual role as an oncogene and tumor suppressor gene in several tumors;differentiating between these roles may depend on the YAP1 phosphorylation pattern.The specific function of YAP1 in B cell acute lymphoblastic leukemia(B-ALL),however,is currently unclear.Thus,in the present study,the role of YAP1 in B-ALL was investigated using relevant cell lines and patient datasets.Methods The effects of shRNA-mediated knockdown on YAP1 and LATS1 levels in the NALM6 and MOLT-4 cell lines were examined using Western blotting,quantitative real-time polymerase chain reaction,flow cytometry,immunostaining,and nude mouse subcutaneous tumorigenesis experiments.Gene expression levels of Hippo pathway-related molecules before and after verteporfin(VP)treatment were compared using RNA-Seq to identify significant Hippo pathway-related genes in NALM6 cells.Results Patients with ALL showing high YAP1 expression and low YAP1-Ser127 phosphorylation levels had worse prognoses than those with low YAP1 protein expression and high YAP1-Ser127 phosphorylation levels.YAP1-Ser127 phosphorylation levels were lower in NALM6 cells than in MOLT-4 and control cells;YAP1 was distributed in the nuclei in NALM6 cells.Knockdown of YAP1 inhibited MOLT-4 and NALM6 cell proliferation and arrested the NALM6 cell cycle in the G0/G1 phase.Before and after VP treatment,the expression of the upstream gene LATS1 was upregulated;its overexpression promoted YAP1-Ser127 phosphorylation.Further,YAP1 was distributed in the plasma.Conclusion LATS1 may downregulate YAP1-Ser127 phosphorylation and maintain B-ALL cell function;thus,VP,which targets this axis,may serve as a new therapeutic method for improving the outcomes for B-ALL patients.
文摘AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.
基金This work was supported by the Basic Research Program of Yunnan Province-Joint Project of Kunming Medical University No.202101AY070001−169.
文摘Background:Lung adenocarcinoma is a very pervasive histological form of lung cancers,and inhibiting metastasis is crucial for effective treatment.In this investigation,we explored the functional interaction of miR-30a-5p and the putative transcription factor 2 of the homeodomain(PHTF2)in dictating the aggressiveness and metastasis of lung adenocarcinoma.Method:We collected clinical samples to evaluate the expression patterns of miR-30a-5p and PHTF2 in lung adenocarcinoma along with normal tissues.Cellular experiments including cell count kit(CCK)-8 growth assay,apoptosis analysis,migration and invasion examinations were performed to assess the aggressiveness of lung adenocarcinoma cells.Furthermore,we examined tumorigenesis and metastasis in a nude mouse model.Results:MiR-30a-5p exhibited downregulation pattern in lung adenocarcinoma samples.Transfection of miR-30a-5p mimic in lung adenocarcinoma cells resulted in the suppression of malignant characteristics.Notably,the administration of miR-30a-5p mimic also curbed tumorigenesis and metastasis of lung adenocarcinoma cells in animal model.Moreover,PHTF2 was found to be a molecular target of miR-30a-5p.Upregulating PHTF2 counteracted the tumor-suppressive effect of the miR-30a-5p mimic.Conclusion:miR-30a-5p functions as a tumor-suppressive molecule while PHTF2 acts as an oncogenic factor in the development and metastasis of lung adenocarcinoma.Therefore,targeting miR-30a-5p and PHTF2 could be developed into a promising therapeutic approach for inhibiting metastasis in lung adenocarcinoma.
基金Supported by the National Natural Science Foundation of China,No.92159305National Key R&D Program of China,No.2023YFC2308104.
文摘BACKGROUND Hepatocellular carcinoma(HCC)is a major cause of cancer mortality worldwide,and metastasis is the main cause of early recurrence and poor prognosis.However,the mechanism of metastasis remains poorly understood.AIM To determine the possible mechanism affecting HCC metastasis and provide a possible theoretical basis for HCC treatment.METHODS The candidate molecule lecithin-cholesterol acyltransferase(LCAT)was screened by gene microarray and bioinformatics analysis.The expression levels of LCAT in clinical cohort samples was detected by quantitative realtime polymerase chain reaction and western blotting.The proliferation,migration,invasion and tumor-forming ability were measured by Cell Counting Kit-8,Transwell cell migration,invasion,and clonal formation assays,respectively.Tumor formation was detected in nude mice after LCAT gene knockdown or overexpression.The immunohistochemistry for Ki67,E-cadherin,N-cadherin,matrix metalloproteinase 9 and vascular endothelial growth factor were performed in liver tissues to assess the effect of LCAT on HCC.Gene set enrichment analysis(GSEA)on various gene signatures were analyzed with GSEA version 3.0.Three machine-learning algorithms(random forest,support vector machine,and logistic regression)were applied to predict HCC metastasis in The Cancer Genome Atlas and GEO databases.RESULTS LCAT was identified as a novel gene relating to HCC metastasis by using gene microarray in HCC tissues.LCAT was significantly downregulated in HCC tissues,which is correlated with recurrence,metastasis and poor outcome of HCC patients.Functional analysis indicated that LCAT inhibited HCC cell proliferation,migration and invasion both in vitro and in vivo.Clinicopathological data showed that LCAT was negatively associated with HCC size and metastasis(HCC size≤3 cm vs 3-9 cm,P<0.001;3-9 cm vs>9 cm,P<0.01;metastatic-free HCC vs extrahepatic metastatic HCC,P<0.05).LCAT suppressed the growth,migration and invasion of HCC cell lines via PI3K/AKT/mTOR signaling.Our results indicated that the logistic regression model based on LCAT,TNM stage and the serum level of α-fetoprotein in HCC patients could effectively predict high metastatic risk HCC patients.CONCLUSION LCAT is downregulated at translational and protein levels in HCC and might inhibit tumor metastasis via attenuating PI3K/AKT/mTOR signaling.LCAT is a prognostic marker and potential therapeutic target for HCC.
文摘Objective: To investigate whether deletion of chromosome 3 is involved in the carcinogenesis of primary glioblastoma multiforme (GBM) and to localize the possible common deletion region in the aforementioned chromosome. Methods: PCR based microsatellite polymorphism analyses were performed to detect loss of heterozygosity (LOH). Twenty-three loci on chromosome 3 were examined in 20 cases of GBM. Fluorescence-labeled primers and Perkin Elmer 377 DNA Sequencer were applied. Results: 50% informative cases of GBM displayed LOH on chromosome 3. 50% of informative cases displayed LOH on 3q and 35% on 3p. 25.6% of informative loci showed LOH in our series, in which frequent LOH were observed in the chromosomal region from loci D3S1614 (42.9%) to D3S1565 (35.3%) on 3q24–27 and at loci D3S1569 (35.3%) on 3q22–23 and D3S1289 (33.3%) on 3p14.1–14.3. Conclusion: Loss of genetic material on chromosome 3 may play an important part in the tumorigenesis of GBM. The chromosomal regions from loci D3S1614 to D3S1565 on 3q24–27 and at loci D3S1569 on 3q22–23 and D3S1289 on 3p14.1–14.3 are potential sites for novel tumor suppressor genes associated with GBM.
文摘Objective: To investigate whether deletion of chromosome 17 is involved in the carcinogenesis of primary glioblastoma multiforme and to localize the possible common deletion region in the aforementioned chromosome. Methods: Polymerase chain reaction-based microsatellite analysis was used to assess loss of heterozygosity (LOH) on chromosome 17 in 20 primary glioblastoma multiforme (GBM). Fifteen fluorescent dye-labeled polymorphic markers were used. Results: Thirteen of twenty (65%) GBM displayed LOH on at least one marker of chromosome 17p. Two tumors showed either LOH or non-informativeness on all markers tested. The most frequent LOH was observed at loci including D17s799 (53.3%), D17s1852 (53.8%), D17s938 (63.20/o), D17s831 (55.6%). The loci D17s831 (on 17p13) and D17s799–D17s1852 (17p11.2–p12) are distal and proximal to p53 respectively. The frequencies of LOH at all loci examined on chromosome 17q were relatively low (<30%). None of informative loci exhibited microsatellite instability in this study. Conclusion: Loss of genetic material on chromosome 17p may play an important role in the pathogenesis of GBM. Besides the well-known TSG p53 on 17p, other unknown TSCs associated with GBM may be present on the chromosomal regions 17p13 and 17p11.2–p12, which are distal and proximal to p53 respectively.
文摘Data obtained in experimental cutaneous melanomas have suggested that the nm23 gene may function as a metastasis suppressor gene. The nm23 level in 8 human cutaneous melanoma cell lines and 2 murine melanoma cell lines were examined. Each melanoma cell line was transplanted subcutaneously into the flank of nude mice, and the metastatic behavior was evaluated by counting lung tumor fool and by determining host survival time. It was found that expression of 'm23 mRNA in human melanomas is correlated closely with reduced metastatic behavior in experimental animals and may serve as a sensitive prognostic indicator of malignancy and survival in patients with melanomas.
基金Supported by The National Natural Science Foundation of China, No. 30080016 and No. 30470977
文摘AIM: To study the candidate tumor suppressor genes (TSG) on chromosome 4p by detecting the high frequency of loss of heterozygosity (LOH) in sporadic colorectal carcinoma in Chinese patients.METHODS: Seven fluorescent labeled polymorphic microsatellite markers were analyzed in 83 cases of colorectal carcinoma and matched normal tissue DNA by PCR. PCR products were eletrophoresed on an ABI 377 DNA sequencer. Genescan 3.7 and Genotype 3.7 software were used for LOH scanning and analysis. The same procedure was performed by the other six microsatellite markers spanning D4S3013 locus to make further detailed deletion mapping. Comparison between LOH frequency and clinicopathological factors was performed by χ2 test.RESULTS: Data were collected from all informative loci. The average LOH frequency on 4p was 24.25%, and 42.3% and 35.62% on D4S405 and D4S3013 locus, respectively. Adjacent markers of D4S3013 displayed a low LOH frequency (< 30%) by detailed deletion mapping. Significant opposite difference was observed between LOH frequency and tumor diameter on D4S412 and D4S1546 locus (0% vs 16.67%, P = 0.041; 54.55% vs 11.11%, P = 0.034, respectively). On D4S403 locus, LOH was significantly associated with tumor gross pattern (11.11%, 0, 33.33%, P = 0.030). No relationship was detected on other loci compared with clinicopathologial features.CONCLUSION: By deletion mapping, two obvious high frequency LOH regions spanning D4S3013 (4p15.2) and D4S405 (4p14) locus are detected. Candidate TSG, which is involved in carcinogenesis and progression of sporadic colorectal carcinoma on chromosome 4p, may be located between D4S3017 and D4S2933 (about 1.7 cm).
文摘Objective: To investigate the correlation of Runt-related transcription factor 2 (RunX2) with proliferation genes, tumor suppressor genes and angiogenesis molecules in colon cancer lesions. Methods: A total of 90 patients with primary colon cancer were enrolled in colon cancer group, 68 patients with benign colon polyps were enrolled in colon polyps group, the differences in the expression levels of RunX2, proliferation genes, tumor suppressor genes and angiogenesis molecules in the two groups of lesions were compared, and Pearson test was further used to evaluate the correlation of RunX2 expression level with proliferation gene, tumor suppressor gene and angiogenesis molecule expression levels in colon cancer tissues. Results: RunX2 mRNA expression level in the lesions of colon cancer group was higher than that of colon polyps group. Proliferation genes GTPBP4, HOXB7, ZNF331, ADAM17 and HSP60 mRNA expression levels in the lesions of colon cancer group were higher than those of colon polyps group;tumor suppressor genes ATF3, FOXN3, OTUD1 and NDRG2 mRNA expression levels were lower than those of colon polyps group;angiogenesis molecules Musashi 1, NF-κB, RegⅣ and STAT3 mRNA expression levels were higher than those of colon polyps group. RunX2 mRNA expression level in the colon cancer lesions was directly correlated with the expression levels of the above proliferation genes, tumor suppressor genes and angiogenesis molecules. Conclusion: RunX2 expression is abnormally high in colon cancer lesions, the specific expression level is positively correlated with cancer cell proliferation activity and angiogenesis activity, and it is an important molecular target that can lead to the occurrence and development of colon cancer.