BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene ma...BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen II synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair.展开更多
In the world,hepatocellular carcinoma(HCC)is among the top 10 most prevalent malignancies.HCC formation has indeed been linked to numerous etiological factors,including alcohol usage,hepatitis viruses and liver cirrho...In the world,hepatocellular carcinoma(HCC)is among the top 10 most prevalent malignancies.HCC formation has indeed been linked to numerous etiological factors,including alcohol usage,hepatitis viruses and liver cirrhosis.Among the most prevalent defects in a wide range of tumours,notably HCC,is the silencing of the p53 tumour suppressor gene.The control of the cell cycle and the preservation of gene function are both critically important functions of p53.In order to pinpoint the core mechanisms of HCC and find more efficient treatments,molecular research employing HCC tissues has been the main focus.Stimulated p53 triggers necessary reactions that achieve cell cycle arrest,genetic stability,DNA repair and the elimination of DNA-damaged cells’responses to biological stressors(like oncogenes or DNA damage).To the contrary hand,the oncogene protein of the murine double minute 2(MDM2)is a significant biological inhibitor of p53.MDM2 causes p53 protein degradation,which in turn adversely controls p53 function.Despite carrying wt-p53,the majority of HCCs show abnormalities in the p53-expressed apoptotic pathway.High p53 in-vivo expression might have two clinical impacts on HCC:(1)Increased levels of exogenous p53 protein cause tumour cells to undergo apoptosis by preventing cell growth through a number of biological pathways;and(2)Exogenous p53 makes HCC susceptible to various anticancer drugs.This review describes the functions and primary mechanisms of p53 in pathological mechanism,chemoresistance and therapeutic mechanisms of HCC.展开更多
Tumor protein p53 (TP53) mediates DNA repair and cell proliferation in growing cells. The TP53 gene is a tumor suppressor that regulates the expression of target genes in response to multiple cellular stress factors. ...Tumor protein p53 (TP53) mediates DNA repair and cell proliferation in growing cells. The TP53 gene is a tumor suppressor that regulates the expression of target genes in response to multiple cellular stress factors. Key target genes are involved in crucial cellular events such as DNA repair, cell cycle regulation, apoptosis, metabolism, and senescence. TP53 genetic variants and the activity of the wild-type p53 protein (WT-p53) have been linked to a wide range of tumorigenesis. Various genetic and epigenetic alterations, including germline and somatic mutations, loss of heterozygosity, and DNA methylation, can alter TP53 activity, potentially resulting in cancer initiation and progression. This study was designed to screen three reported mutations in the DNA-binding domain of the p53 protein in breast cancer, to evaluate the relative susceptibility and risk associated with breast cancer in the local population. Genomic DNA was isolated from 30 breast tumor tissues along with controls. Tetra and Tri ARMS PCR were performed to detect mutations in the TP53 coding region. For SNPs c.637C>T and c.733C>T, all analyzed cases were homozygous for the wild-type allele ‘C,’ while for SNP c.745A>G, all cases were homozygous for the wild-type allele ‘A.’ These results indicate no relevance of these three SNPs to cancer progression in our study cohort. Additionally, the findings from whole exon sequencing will help to predict more precise outcomes and assess the importance of TP53 gene mutations in breast cancer patients.展开更多
BACKGROUND Dilated cardiomyopathy(DCM)is a genetically heterogeneous cardiac disorder characterized by left ventricular dilation and contractile dysfunction.The substantial genetic heterogeneity evident in patients wi...BACKGROUND Dilated cardiomyopathy(DCM)is a genetically heterogeneous cardiac disorder characterized by left ventricular dilation and contractile dysfunction.The substantial genetic heterogeneity evident in patients with DCM contributes to variable disease severity and complicates overall prognosis,which can be very poor.AIM To identify pathogenic genes in DCM through pedigree analysis.METHODS Our research team identified a patient with DCM in the clinic.Through invest-igation,we found that the family of this patient has a typical DCM pedigree.High-throughput sequencing technology,next-generation sequencing,was used to sequence the whole exomes of seven samples in the pedigree.RESULTS A novel and potentially pathogenic gene mutation-ANK2p.F3067L-was discovered.The mutation was completely consistent with the clinical information for this DCM pedigree.Sanger sequencing was used to further verify the locus of the mutation in pedigree samples.These results were consistent with those of high-throughput sequencing.CONCLUSIONS ANK2p.F3067L is considered a novel and potentially pathogenic gene mutation in DCM.展开更多
INTRODUCTIONIn order to study the relationship between oncogeneexpression and HCC generation,we observed theprecancerous hepatic GGT loci,IGF-Ⅱ,p53 andp21 expression during hepatocarcinogenesis of treeshrew induced b...INTRODUCTIONIn order to study the relationship between oncogeneexpression and HCC generation,we observed theprecancerous hepatic GGT loci,IGF-Ⅱ,p53 andp21 expression during hepatocarcinogenesis of treeshrew induced by hepatitis B virus (HBV) and/oraflatoxin B1 (AFB1).展开更多
AIM To study the correlationship between the changes of p53, Waf1p21 and the cell proliferation determined by PCNA at different stages of human esophageal carcinogenesis. METHODS Biopsied and resected esophageal ti...AIM To study the correlationship between the changes of p53, Waf1p21 and the cell proliferation determined by PCNA at different stages of human esophageal carcinogenesis. METHODS Biopsied and resected esophageal tissues from a high risk population for esophageal cancer in northern China were used in this study. All the specimens were fixed with 85% alcohol and further processed with routine histology. The avidin biotin peroxidase complex (ABC) method was used for the detection of p53, Waf1p21 and PCNA. RESULTS The strong nuclear staining for p53, Waf1p21 and PCNA was observed in the normal esophageal epithelium and the epithelia with different severities of lesions. As the lesions progressed to dysplasia (DYS) and to esophageal squamons cell carcinoma (SCC), the percentage of Waf1p21 immunoreactivity decreased. The number of Waf1p21 immunostaining positive cells increased slightly from normal to basal cell hyperplasia (BCH), but there was no further increase in DYS and in SCC. The total number of positive cells for Waf1p21 stain appeared to be lower than that of p53 in normal and BCH esophageal epithelia and much lower in DYS and SCC. The Waf1p21 positive immunostaining cells were located at the third and forth cell layers in half of the samples examined, which was 2～4 cell layers higher than that of PCNA and p53 in the same histological categories of normal, BCH and DYS. CLNCLUSION The low levels of Waf1p21 at the stage of DYS may be related to a functional loss of p53. Other mechanisms may also be responsible to the lack of Waf1p21 expression in DYS and SCC.展开更多
AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of ...AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]展开更多
AIM: Although polysaccharides from Phellinus mushrooms are a well-known material with anti-tumor properties, there is no information about the effect of polysaccharides from Phellinus gilvus (PG) on tumor. The modulat...AIM: Although polysaccharides from Phellinus mushrooms are a well-known material with anti-tumor properties, there is no information about the effect of polysaccharides from Phellinus gilvus (PG) on tumor. The modulating effect of polysaccharides isolated from PG on the benzo(a)pyrene (BaP)-induced forestomach carcinogenesis in ICR female mice was investigated in this study.METHODS: A forestomach carcinogenesis model was established in 40 ICR female mice receiving oral administration of BaP for 4 wk. The mice were randomly assigned to 4 groups (10 each). The mice in each group were treated with sterile water or PG for 4 and 8 wk (SW4,PGW4, SW8, and PGW8 groups). Eight or 12 wk after the first dose of BaP, forestomachs were removed for histopathological and RT-PCR analysis.RESULTS: In histopathological changes and RT-PCR analysis, sterile water-treated mice showed significant hyperplasia of the gastric mucosa with a significantly increased expression of mutant p53 mRNA compared to mice treated with PG for 8 wk.CONCLUSION: Polysaccharides isolated from PG may inhibit BaP-induced forestomach carcinogenesis in mice bydown-regulating mutant p53 expression.展开更多
Objective: To study the effects of transferred wild type p73α gene on the sensitivity to the chemotherapeutic agents and the growth of p53-null H1299 cells of human lung adenocarcinoma. Methods: The pcDNA3-HA-p73α p...Objective: To study the effects of transferred wild type p73α gene on the sensitivity to the chemotherapeutic agents and the growth of p53-null H1299 cells of human lung adenocarcinoma. Methods: The pcDNA3-HA-p73α plasmid was transferred into the cultured p53-null H1299 cells of human lung adenocarcinoma with the mediation of Dosper liposome; The cells resistant to G418 were selected. The expression of p73α gene in the cells was examined with Western blot. MTT assay was used to analyze the response of the transfected cells to cis-dichlorodiamine platinum (cDDP) and adriamycin (ADM). The rate of drug-induced apoptosis of the transfected cells was determined with flow cytometry and DNA fragmentation assay. The changes of the biological behaviors were observed with colony formation assay. Results: The transfected H1299 cells of human lung adenocarcinoma over-expressed p73α protein stably. MTT assay showed that the IC 50 values of cDDP and ADM were reduced by approximately 7 fold and 130 fold respectively in the transfected cells as compared with the untransfected ones. Lower concentration of the chemotherapeutic agents (1.25 μmol/L of cDDP and 0.05 μmol/L of ADM) could be employed to suppress markedly the growth of the transfected H1299 cells. The apoptotic rate induced by cDDP was increased from 10.1% to 38 4% (P<0.01) and that of ADM from 12.1% to 49.3% (P<0.01). The clonogenecity after the administration of chemotherapeutic agents was significantly lower in the transfected H1299 cells than in the parental cells (P<0.01). The sensitive enhancement ratios were 1.8 and 2.6 for cDDP and ADM respectively. Conclusion: The transfection of H1299 cells with wild type p73α gene results in an increase of the sensitivity of the cells to chemotherapeutic agents.展开更多
AIM： To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene （IgA1-H chain）, in human epitheliα-derived tumor cells. METHODS： Total RNAs and cell lysates were prepared from five diffe...AIM： To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene （IgA1-H chain）, in human epitheliα-derived tumor cells. METHODS： Total RNAs and cell lysates were prepared from five different human epithelial cell lines derived from lung, stomach, liver, skin, and breast, respectively. RT-PCR and immunoblot analysis of these five cell lines were done. Both RT-PCR and immunochemistry were used to detect the expression of SNC73 in these cell lines. We also examined the expression of SNC73 in normal epithelial cells of colon mucosa by in situ hybridization. RT-PCR and immunoblot analysis were used to determine whether the recombination activating gene1/2 （RAG1 and RAG2） is present. The expression of three immunoglobulin transcription factors, EBF, E2A and Pax5, and the heavy chain of IgA1 and two types of light chains of immunoglobulin （κ and λ） in the aforementioned cell lines were analyzed by RT-PCR and immunochemistry, respectively. All the RT-PCR products were analyzed by sequencing. RESULTS： The results of RT-PCR and immunochemistry showed that both mRNA and protein of SNC73 were expressed in five human epitheliα-derived cancer cell lines. These data were further confirmed in the normal epithelial cells of colon mucosa by in situ hybridization. Also, the heavy chain of IgA1 and κ light chain were detected in these cells, but no λ light chain was observed. Both RAG1 and RAG2 were expressed in these human epitheliα-derived cancer cell lines and the sequence was identical to that expressed in pre-B and pre-T cells. In addition to RAG1 and RAG2, the mRNA in one of the immunoglobulin transcription factors, EBF, was also detected in these cell lines, and Pax5 was only expressed in SW480 cells, but no expression of E2A was observed in all the five cell lines. CONCLUSION： Immunoglobulin A1 is originally expressed and V（D）J recombination machine is also present in non-lymphoid cells, suggesting that V（D）J recombination machine mediates the assembly of immunoglobulin A1 in non-lymphoid cells as in prelymphocytes.展开更多
文摘BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen II synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair.
文摘In the world,hepatocellular carcinoma(HCC)is among the top 10 most prevalent malignancies.HCC formation has indeed been linked to numerous etiological factors,including alcohol usage,hepatitis viruses and liver cirrhosis.Among the most prevalent defects in a wide range of tumours,notably HCC,is the silencing of the p53 tumour suppressor gene.The control of the cell cycle and the preservation of gene function are both critically important functions of p53.In order to pinpoint the core mechanisms of HCC and find more efficient treatments,molecular research employing HCC tissues has been the main focus.Stimulated p53 triggers necessary reactions that achieve cell cycle arrest,genetic stability,DNA repair and the elimination of DNA-damaged cells’responses to biological stressors(like oncogenes or DNA damage).To the contrary hand,the oncogene protein of the murine double minute 2(MDM2)is a significant biological inhibitor of p53.MDM2 causes p53 protein degradation,which in turn adversely controls p53 function.Despite carrying wt-p53,the majority of HCCs show abnormalities in the p53-expressed apoptotic pathway.High p53 in-vivo expression might have two clinical impacts on HCC:(1)Increased levels of exogenous p53 protein cause tumour cells to undergo apoptosis by preventing cell growth through a number of biological pathways;and(2)Exogenous p53 makes HCC susceptible to various anticancer drugs.This review describes the functions and primary mechanisms of p53 in pathological mechanism,chemoresistance and therapeutic mechanisms of HCC.
文摘Tumor protein p53 (TP53) mediates DNA repair and cell proliferation in growing cells. The TP53 gene is a tumor suppressor that regulates the expression of target genes in response to multiple cellular stress factors. Key target genes are involved in crucial cellular events such as DNA repair, cell cycle regulation, apoptosis, metabolism, and senescence. TP53 genetic variants and the activity of the wild-type p53 protein (WT-p53) have been linked to a wide range of tumorigenesis. Various genetic and epigenetic alterations, including germline and somatic mutations, loss of heterozygosity, and DNA methylation, can alter TP53 activity, potentially resulting in cancer initiation and progression. This study was designed to screen three reported mutations in the DNA-binding domain of the p53 protein in breast cancer, to evaluate the relative susceptibility and risk associated with breast cancer in the local population. Genomic DNA was isolated from 30 breast tumor tissues along with controls. Tetra and Tri ARMS PCR were performed to detect mutations in the TP53 coding region. For SNPs c.637C>T and c.733C>T, all analyzed cases were homozygous for the wild-type allele ‘C,’ while for SNP c.745A>G, all cases were homozygous for the wild-type allele ‘A.’ These results indicate no relevance of these three SNPs to cancer progression in our study cohort. Additionally, the findings from whole exon sequencing will help to predict more precise outcomes and assess the importance of TP53 gene mutations in breast cancer patients.
基金Supported by the Jilin Provincial Healthcare Talent Special Program,No.2019SCZT08.
文摘BACKGROUND Dilated cardiomyopathy(DCM)is a genetically heterogeneous cardiac disorder characterized by left ventricular dilation and contractile dysfunction.The substantial genetic heterogeneity evident in patients with DCM contributes to variable disease severity and complicates overall prognosis,which can be very poor.AIM To identify pathogenic genes in DCM through pedigree analysis.METHODS Our research team identified a patient with DCM in the clinic.Through invest-igation,we found that the family of this patient has a typical DCM pedigree.High-throughput sequencing technology,next-generation sequencing,was used to sequence the whole exomes of seven samples in the pedigree.RESULTS A novel and potentially pathogenic gene mutation-ANK2p.F3067L-was discovered.The mutation was completely consistent with the clinical information for this DCM pedigree.Sanger sequencing was used to further verify the locus of the mutation in pedigree samples.These results were consistent with those of high-throughput sequencing.CONCLUSIONS ANK2p.F3067L is considered a novel and potentially pathogenic gene mutation in DCM.
基金the National Natural Science Foundation of China,No.39260033.
文摘INTRODUCTIONIn order to study the relationship between oncogeneexpression and HCC generation,we observed theprecancerous hepatic GGT loci,IGF-Ⅱ,p53 andp21 expression during hepatocarcinogenesis of treeshrew induced by hepatitis B virus (HBV) and/oraflatoxin B1 (AFB1).
文摘AIM To study the correlationship between the changes of p53, Waf1p21 and the cell proliferation determined by PCNA at different stages of human esophageal carcinogenesis. METHODS Biopsied and resected esophageal tissues from a high risk population for esophageal cancer in northern China were used in this study. All the specimens were fixed with 85% alcohol and further processed with routine histology. The avidin biotin peroxidase complex (ABC) method was used for the detection of p53, Waf1p21 and PCNA. RESULTS The strong nuclear staining for p53, Waf1p21 and PCNA was observed in the normal esophageal epithelium and the epithelia with different severities of lesions. As the lesions progressed to dysplasia (DYS) and to esophageal squamons cell carcinoma (SCC), the percentage of Waf1p21 immunoreactivity decreased. The number of Waf1p21 immunostaining positive cells increased slightly from normal to basal cell hyperplasia (BCH), but there was no further increase in DYS and in SCC. The total number of positive cells for Waf1p21 stain appeared to be lower than that of p53 in normal and BCH esophageal epithelia and much lower in DYS and SCC. The Waf1p21 positive immunostaining cells were located at the third and forth cell layers in half of the samples examined, which was 2～4 cell layers higher than that of PCNA and p53 in the same histological categories of normal, BCH and DYS. CLNCLUSION The low levels of Waf1p21 at the stage of DYS may be related to a functional loss of p53. Other mechanisms may also be responsible to the lack of Waf1p21 expression in DYS and SCC.
文摘AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]
基金Supported by grant R08-2003-000-10120-0 from the Basic Research Program of the Korea Science & Engineering Foundation
文摘AIM: Although polysaccharides from Phellinus mushrooms are a well-known material with anti-tumor properties, there is no information about the effect of polysaccharides from Phellinus gilvus (PG) on tumor. The modulating effect of polysaccharides isolated from PG on the benzo(a)pyrene (BaP)-induced forestomach carcinogenesis in ICR female mice was investigated in this study.METHODS: A forestomach carcinogenesis model was established in 40 ICR female mice receiving oral administration of BaP for 4 wk. The mice were randomly assigned to 4 groups (10 each). The mice in each group were treated with sterile water or PG for 4 and 8 wk (SW4,PGW4, SW8, and PGW8 groups). Eight or 12 wk after the first dose of BaP, forestomachs were removed for histopathological and RT-PCR analysis.RESULTS: In histopathological changes and RT-PCR analysis, sterile water-treated mice showed significant hyperplasia of the gastric mucosa with a significantly increased expression of mutant p53 mRNA compared to mice treated with PG for 8 wk.CONCLUSION: Polysaccharides isolated from PG may inhibit BaP-induced forestomach carcinogenesis in mice bydown-regulating mutant p53 expression.
文摘Objective: To study the effects of transferred wild type p73α gene on the sensitivity to the chemotherapeutic agents and the growth of p53-null H1299 cells of human lung adenocarcinoma. Methods: The pcDNA3-HA-p73α plasmid was transferred into the cultured p53-null H1299 cells of human lung adenocarcinoma with the mediation of Dosper liposome; The cells resistant to G418 were selected. The expression of p73α gene in the cells was examined with Western blot. MTT assay was used to analyze the response of the transfected cells to cis-dichlorodiamine platinum (cDDP) and adriamycin (ADM). The rate of drug-induced apoptosis of the transfected cells was determined with flow cytometry and DNA fragmentation assay. The changes of the biological behaviors were observed with colony formation assay. Results: The transfected H1299 cells of human lung adenocarcinoma over-expressed p73α protein stably. MTT assay showed that the IC 50 values of cDDP and ADM were reduced by approximately 7 fold and 130 fold respectively in the transfected cells as compared with the untransfected ones. Lower concentration of the chemotherapeutic agents (1.25 μmol/L of cDDP and 0.05 μmol/L of ADM) could be employed to suppress markedly the growth of the transfected H1299 cells. The apoptotic rate induced by cDDP was increased from 10.1% to 38 4% (P<0.01) and that of ADM from 12.1% to 49.3% (P<0.01). The clonogenecity after the administration of chemotherapeutic agents was significantly lower in the transfected H1299 cells than in the parental cells (P<0.01). The sensitive enhancement ratios were 1.8 and 2.6 for cDDP and ADM respectively. Conclusion: The transfection of H1299 cells with wild type p73α gene results in an increase of the sensitivity of the cells to chemotherapeutic agents.
文摘AIM： To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene （IgA1-H chain）, in human epitheliα-derived tumor cells. METHODS： Total RNAs and cell lysates were prepared from five different human epithelial cell lines derived from lung, stomach, liver, skin, and breast, respectively. RT-PCR and immunoblot analysis of these five cell lines were done. Both RT-PCR and immunochemistry were used to detect the expression of SNC73 in these cell lines. We also examined the expression of SNC73 in normal epithelial cells of colon mucosa by in situ hybridization. RT-PCR and immunoblot analysis were used to determine whether the recombination activating gene1/2 （RAG1 and RAG2） is present. The expression of three immunoglobulin transcription factors, EBF, E2A and Pax5, and the heavy chain of IgA1 and two types of light chains of immunoglobulin （κ and λ） in the aforementioned cell lines were analyzed by RT-PCR and immunochemistry, respectively. All the RT-PCR products were analyzed by sequencing. RESULTS： The results of RT-PCR and immunochemistry showed that both mRNA and protein of SNC73 were expressed in five human epitheliα-derived cancer cell lines. These data were further confirmed in the normal epithelial cells of colon mucosa by in situ hybridization. Also, the heavy chain of IgA1 and κ light chain were detected in these cells, but no λ light chain was observed. Both RAG1 and RAG2 were expressed in these human epitheliα-derived cancer cell lines and the sequence was identical to that expressed in pre-B and pre-T cells. In addition to RAG1 and RAG2, the mRNA in one of the immunoglobulin transcription factors, EBF, was also detected in these cell lines, and Pax5 was only expressed in SW480 cells, but no expression of E2A was observed in all the five cell lines. CONCLUSION： Immunoglobulin A1 is originally expressed and V（D）J recombination machine is also present in non-lymphoid cells, suggesting that V（D）J recombination machine mediates the assembly of immunoglobulin A1 in non-lymphoid cells as in prelymphocytes.
