AIM: To determine the expression of HER2 and bradykinin B1 receptors (B1R) in the two pathogenic models of gallbladder cancer: the metaplasia dysplasia carcino ma and the adenoma carcinoma pathways.METHODS: Recep...AIM: To determine the expression of HER2 and bradykinin B1 receptors (B1R) in the two pathogenic models of gallbladder cancer: the metaplasia dysplasia carcino ma and the adenoma carcinoma pathways.METHODS: Receptor proteins were visualized by immunohistochemistry on 5-μm sections of paraffin-embedded tissue. Expression of both receptors was studied in biopsy samples from 92 patients (6 males and 86 females; age ranging from 28 to 86 years, mean 56 years). High HER2 expression in specimens was additionally investigated by fluorescence in situ hybridization. Cell proliferation in each sample was assessed by using the Ki-67 proliferation marker.RESULTS: HER2 receptor protein was absent in adenomas and in normal gallbladder epithelium. On the contrary, there was intense staining for HER2 on the basolateral membrane of epithelial cells of intestinal metaplasia (22/24; 91.7%) and carcinoma in situ (9/10; 90%), the lesions that displayed a significantly high proliferation index. Protein up-regulation of HER2 in the epithelium with metaplasia or carcinoma in s/tu was not accompanied by HER2 gene amplification. A similar result was observed in invasive carcinomas (0/12). The B1R distribution pattern mirrored that of HER2 except that B1R was additionally observed in the adenomas. The B1R appeared either as cytoplasmic dots or labeling on the apical cell membrane of the cells composing the epithelia with intestinal metaplasia (24/24; 100%) and carcinoma in situ (10/10; 100%) and in the epithelial cells of adenomas. In contrast, both HER2 (4/12; 33%) and B1R (1/12; 8.3%) showed a low expression in inva- sive gallbladder carcinomas.CONCLUSION: The up-regulation of HER2 and B1R in precursor lesions of gallbladder carcinoma suggests cross-talk between these two receptors that may be of importance in the modulation of cell proliferation in gallbladder carcinogenesis,展开更多
AIM: To examine the expression of leptin and its receptor, OB-R, in normal gastric mucosa and neoplasia. METHODS: By immunohistochemical staining using specifi c antibodies, we evaluated the expression of leptin and O...AIM: To examine the expression of leptin and its receptor, OB-R, in normal gastric mucosa and neoplasia. METHODS: By immunohistochemical staining using specifi c antibodies, we evaluated the expression of leptin and OB-R in 207 gastric carcinomas (100 early and 107 advanced carcinomas) and analyzed their relationship with clinicopathological features. RESULTS: Both normal gastric epithelium and carci- noma cells expressed a significant level of leptin. In cases with OB-R staining, carcinoma cells showed OB-R- positive expression, but the intensity was weaker than that in normal mucosa. The expression of OB-R showed a signifi cant correlation with the level of leptin expres- sion. The expression levels of both leptin and OB-R tend- ed to increase as the depth of tumor invasion or TMN stage increased (P < 0.01). Lymph node metastasis was detected in 49.5% (47/95) of leptin-strong cases and in 50.5% (48/95) of OB-R-positive cases, and the rate was 33% (37/112) in leptin-weak cases and 17% (19/112) in OB-R-negative cases. Both venous and lymphatic inva- sion also tended to be observed frequently in positive tumors as compared with negative tumors. Interestingly, in the 96 leptin- or OB-R-positive tumors, hematogenous metastasis was detected preoperatively in 3 (3.1%) pa- tients. In contrast, none of the carcinomas that lacked expression of leptin and OB-R showed hematogenous metastasis. CONCLUSION: Overexpression of leptin and expres- sion of OB-R may play a positive role in the process of progression in gastric cancer. Functional upregulation of leptin/OB-R may have a positive role in the development and initial phase of progression in gastric cancer.展开更多
AIM: TO determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis. METHODS: The Ku70/80 DNA-binding activity w...AIM: TO determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis. METHODS: The Ku70/80 DNA-binding activity was determined by electrophoretic mobility shift assays in 20 colon adenoma and 15 colorectal cancer samples as well as matched normal colonic tissues. Nuclear and cytoplasmic protein expression was determined by immunohistochemistry and Western blot analysis. RESULTS: A statistical found in both adenomas y significant difference was and carcinomas as compared to matched normal colonic mucosa (P〈0.00). However, changes in binding activity were not homogenous with approximately 50% of the tumors showing a clear increase in the binding activity, 30% displaying a modest increase and 15% showing a decrease of the activity.Tumors, with increased DNA-binding activity, also showed a statistically significant increase in Ku70 and Ku86 nuclear expression, as determined by Western blot and immunohistochemical analyses (P〈0.001). Cytoplasmic protein expression was found in pathological samples, but not in normal tissues either from tumor patients or from healthy subjects. CONCLUSION: Overall, our DNA-binding activity and protein level are consistent with a substantial activation of the NHEJ pathway in colorectal tumors. Since the NHEJ is an error prone mechanism, its abnormal activation can result in chromosomal instability and ultimately lead to tumorigenesis.展开更多
Objective To investigate the effects of small interfering RNA (siRNA) recombinant expression vector targeting survivin gene on chemotherapy sensitivity of human colon cancer cells to 5-fluorouracil. Methods siRNA re...Objective To investigate the effects of small interfering RNA (siRNA) recombinant expression vector targeting survivin gene on chemotherapy sensitivity of human colon cancer cells to 5-fluorouracil. Methods siRNA recombinant expression vector targeting survivin gene was constructed and transfected into human colon cancer cell lines LOVO. After 48 hours of transfection, cells were harvested for analysis of survivin mRNA and protein expressions using RT-PCR and Western blot. In addition, after human colon cancer cell lines were treated with Survivin siRNA and/or 5-fluorouracil, MTT assay and flow cytometry were used to analyze cell proliferation and apoptosis. Results Restriction endonuclease analysis confirmed that siRNA recombinant expression vector targeting survivin gene was successfully constructed. Inhibitory ratios of survivin mRNA and protein expressions by Survivin siRNA were 36.33% and 44.65%, respectively. Survivin siRNA combined with 5-fluorouracil significantly increased the cell proliferation inhibitory ratio and apoptosis ratio compared with 5-fluorouracil treatin~ alone (P〈0.05). Conclusion The siRNA recombinant expression vector targeting survivin gene can inhibit the expression of survivin gene, and enhance chemotherapy sensitivity of human colon cancer cells to 5- fluorouracil.展开更多
AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of the...AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of themismatch repair(MMR)machinery in colorectal tumors.METHODS:The CA-SSRⅠgenotype was analyzed ina total of 86 primary colorectal tumors,selected upontheir microsatellite instability(MSI)status[42 with highfrequency MSI(MSI-H)and 44 microsatellite stable(MSS)]and their respective normal tissue.The effect of the CA-SSRⅠgenotype on the expression of the EGFR gene wasevaluated in 18 specimens using quantitative real-timereverse transcription PCR and immunohistochemistry.RESULTS:Mutations in CA-SSRⅠwere detected in 86%(36 of 42)of MSI-H colorectal tumors and 0%(0 of 44)ofMSS tumors,indicating the EGFR gene as a novel putativespecific target of the defective MMR system(P<0.001).Impaired expression of EGFR was detected in most ofthe colorectal tumors analyzed[6/12(50%)at the mRNAlevel and 15/18(83%)at the peptide level].However,noassociation was apparent between EGFR expression andCA-SSRⅠstatus in tumors or normal tissues.CONCLUSION:Our results suggest that CA-SSRⅠsequence does not contribute to the regulation of EGFRtranscription in colon,and should thus not be consideredas a promising predictive marker for response to EGFRinhibitors in patients with colorectal cancer.展开更多
AIM: To investigate the regulation of phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene expression in human hepatocellular carcinoma (HCC) cell lines.METHODS: The mRNA and protein levels of PTEN wer...AIM: To investigate the regulation of phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene expression in human hepatocellular carcinoma (HCC) cell lines.METHODS: The mRNA and protein levels of PTEN were detected by Northern blot and Western blot in HCC cell lines, respectively. Plasmids containing different fragments of PTEN promoter with Luciferase reporter were constructed and transiently transfected into HCC cell lines to study the promoter activity. DNA analysis and RT-PCR were performed to detect the mutation of PTEN promoter and PTEN cDNA.RESULTS: Either protein or mRNA levels of PTEN in L02 cells (as a control) were significantly higher than that in HCC cell lines. The profile of PTEN promoter activity in 8 cell lines was closely correlated with levels of PTEN mRNA and PTEN protein. Furthermore, the sequence analysis of 8 cells lines showed no mutation in the region of PTEN promoter and PTENcDNA.CONCLUSION: PTEN expression is down-regulated in HCC cell lines probably due to loss of activity of PTEN promoter.展开更多
To construct ScFv and Fab from murine anti gastric cancer monoclonal antibody(mAb)3H11. Methods.At first,3H11 ScFv and Fab were constructed with V genes PCR amplified by degenerate primers for FR1.The bacterial expres...To construct ScFv and Fab from murine anti gastric cancer monoclonal antibody(mAb)3H11. Methods.At first,3H11 ScFv and Fab were constructed with V genes PCR amplified by degenerate primers for FR1.The bacterial expressed 3H11 Ab fragments showed no antigen binding activity.Then,phage antibody library and random mutated library were constructed from 3H11 hybridoma cells and panning selection was performed.Again the identification of positive clone was failed.Finally the N terminal sequences of V regions were resumed to 3H11 original sequences by site directed mutagenesis via PCR. Results.Binding activity to gastric cancer cells was detected only from N terminal sequence corrected 3H11 ScFv and Fab,though the expression of the Ab fragments was not affected.Correction of either VL or VH N terminal sequences could partially resume the antigen binding activity. Conclusion.Sequence changes of V region N terminal introduced by PCR may seriously affect antigen binding without affecting the expression of antibody.展开更多
AIM: To describe the significant over-expression of fibroblast growth factor receptor 3 (FGFR3), which is a signal transduction and cell proliferation related gene in hepatocellular carcinoma (HCC).METHODS: Following ...AIM: To describe the significant over-expression of fibroblast growth factor receptor 3 (FGFR3), which is a signal transduction and cell proliferation related gene in hepatocellular carcinoma (HCC).METHODS: Following DNA microarray, Northern blot and quantitative real-time PCR were employed to confirm FGFR3 expression difference in HCC tissues and surrounding non-neoplastic liver tissue. FGFR3 expression levels were further determined by immunohistochemical study in 43 cases of HCC.RESULTS: Northern blot results showed the significant over-expression of FGFR3 in HCC tissues, which was consistent with that from DNA microarray. Quantitative real-time PCR demonstrated that the mean ratio of FGFR3 mRNA to glyceraldehyde-3-phosphate dehydrogenase (GADPH) mRNA in HCC tissue was 0.250, whereas the ratio in non-neoplastic liver tissue was 0.014. Statistical analyses of 43 cases of HCC revealed that HCC scored higher than the matched non-neoplastic liver tissues.Examination of clinicopathological features revealed a strong correlation of over-expression of FGFR3 with poor tumor differentiation and high nuclear grade.CONCLUSION: Over-expression of FGFR3 may play an important role in liver carcinogenesis. FGFR3 may be an ideal candidate as a molecular marker in the diagnosis of HCC and a potential therapeutic target.展开更多
A recombinant plasmid containing a full length human epidermal growth factor receptor (EGFR) cDNA sequence in antisense orientation was transferred into cells of a human liver carcinoma cell line BEL-7404. Compared wi...A recombinant plasmid containing a full length human epidermal growth factor receptor (EGFR) cDNA sequence in antisense orientation was transferred into cells of a human liver carcinoma cell line BEL-7404. Compared with the control cell clone JX-0 transferred with the vector plasmid and the parent BEL-7404 cells, the antisense EGFR transferred cell clone JX-1 showed a decreased EGFR gene expression and reduced significantly the growth potential either in anchorage-dependent or anchorage-independent growth. Furthermore. JX-1 cells appeared to be distinctly dependent on serum concentration for monolayer growth. The results suggested that antisense EGFR could partly block the EGFR gene ex-pression and reverse the malignant growth properties of human liver carcinoma cells in vitro.展开更多
AIM: To examine whether lysophosphatidic acid (LPA) induces phosphorylation of c-Met and epidermal growth factor receptor (EGFR), both of which have been proposed as prognostic markers of colorectal cancer, and w...AIM: To examine whether lysophosphatidic acid (LPA) induces phosphorylation of c-Met and epidermal growth factor receptor (EGFR), both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 (COX-2) expression in human colon cancer cells. METHODS: Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis, followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis. RESULTS: Immunoprecipitation analysis revealed that 10 μmol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 IJmol/L LPA induced COX-2 expression in a dose-dependent manner. CONCLUSION: Our results suggest that LPA acts upstream of various receptor tyrosine kinases (RTKs) and COX-2, and thus may act as a potent stimulator of colorectal cancer. 2005 The WJG Press and Elsevier Inc. All rights reserved.展开更多
AIM: To investigate the expression of Toll-like receptor (TLR) 3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma (ESCC). METHODS: Reverse transcription-polymerase chain reaction and immunohistochemistry wer...AIM: To investigate the expression of Toll-like receptor (TLR) 3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma (ESCC). METHODS: Reverse transcription-polymerase chain reaction and immunohistochemistry were used to analyze the expression of TLR3, TLR4, TLR7 and TLR9 mRNA and protein in samples from 87 esophageal cancer patients consisting of both tumor and normal tissue. RESULTS: A significant increase in TLR3, TLR4, TLR7 and TLR9 mRNA levels was detected in ESCC samples. Tumors exhibited high TLR protein expression, (70.1%, 72.4%, 66.7% and 78.2% for TLR3, TLR4, TLR7 and TLR9, respectively, P < 0.05). Nevertheless, a significant percentage of tumors also exhibited TLR4 expression in mononuclear inflammatory cells (48.3%) and TLR9 expression in fibroblast-like cells (60.9%). Tumors with high TLR3 expression in tumor cells or high TLR4 expression in mononuclear inflammatory cells were significantly associated with a higher probability of lymph node metastasis and increased depth of invasion. However, tumors with high TLR9 expression in fibroblast-like cells were associated with low probabilities of invasion and metastasis. There was no significant variation between the expression of TLR3, TLR4, TLR7 and TLR9 among different ethnic groups. CONCLUSION: TLR3, TLR4, TLR7 and TLR9 expression appears important to the biological pathogenesis of ESCC. TLRs may represent therapeutic targets for ESCC.展开更多
AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were u...AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were used.Overexpression of Dkk-3 induced by pEGFP-N1-Dkk-3-GFP plasmid in LoVo cells was performed using Lipofectamine 2000 reagent.Reverse transcription polymerase chain reaction and Western blotting were performed to determine the mRNA and protein expression levels of Dkk-3,respectively.Cell proliferation assay,cell cycle analysis,hoechst 33258 assay and Matrigel invasion assay were performed on Dkk-3 overexpressing transfectants.RESULTS:The mRNA and protein expressions of Dkk-3 in HT-29(mRNA:0.06 ± 0.02,protein:0.06 ± 0.01) and LoVo(mRNA:0.07 ± 0.02,protein:0.07 ± 0.02) cells were significantly lower than that in SW480 cells(mRNA:0.92 ± 0.04,protein:0.69 ± 0.13;all P < 0.05),and the greatest levels of invasiveness wasin LoVo cells.Dkk-3 overexpression inhibited the proliferation and invasion of LoVo cells and induced cell cycle arrest at G0/G1 phase and subsequent apoptosis,as indicated by increased chromatin condensation and fragments,upregulated Bax and cytochrome c protein,downregulated survivin and Bcl-2 protein,and the activation of caspase-3 and caspase-9.Furthermore,Dkk-3 overexpression reduced the accumulation of cytosolic fraction of β-catenin.CONCLUSION:Dkk-3 overexpression induced apoptosis in human colon cancer possibly through the mitochondrial pathway.Dkk-3 may be involved in the Wnt/β-catenin signaling pathways in colon cancer.展开更多
AIM:To analyze the pathogenetic role and potential clinical usefulness of the epidermal growth factor receptor(EGFR)and the human epidermal growth factor receptor 2(HER2)in patients with advanced biliary tract cancer(...AIM:To analyze the pathogenetic role and potential clinical usefulness of the epidermal growth factor receptor(EGFR)and the human epidermal growth factor receptor 2(HER2)in patients with advanced biliary tract cancer(BTC). METHODS:EGFR and HER2 expression was studied in biopsy samples from 124 patients(51%women; median age 64.8 years),with advanced BTC diagnosed between 1997 and 2004.Five micrometers sections of paraffin embedded tissue were examined by standard, FDA approved immunohistochemistry.Tumors with scores of 2+or 3+for HER2 expression on immunochemistry were additionally tested for HER2 gene amplification by fluorescence in situ hybridisation(FISH).RESULTS:34/124 patients(27.4%)had gallbladder cancer,47(37.9%)had intrahepatic BTC and 43(34.7%)had extrahepatic or perihilar BTC.EGFR expression was examined in a subset of 56 samples. EGFR expression was absent in 22/56 tumors(39.3%). Of the remaining samples expression was scored as 1+in 12(21.5%),2+in 13(23.2%)and 3+in 9(16%), respectively.HER2 expression was as follows:score 0 73/124(58.8%),score 1+27/124(21.8%),score 2+ 21/124(17%)and score 3+4/124(3.2%).HER2 gene amplification was present in 6/124,resulting in an overall amplification rate of 5%. CONCLUSION:Our data suggest that routine testing and therapeutic targeting of HER2 does not seem to be useful in patients with BTC,while targeting EGFR may be promising.展开更多
OBJECTIVE To explore the expression of β-tubulin in premalignant lesions and carcinomas of the breast, and to observe the relationship of its expression with breast cancer pathological features. METHODS The expressio...OBJECTIVE To explore the expression of β-tubulin in premalignant lesions and carcinomas of the breast, and to observe the relationship of its expression with breast cancer pathological features. METHODS The expression of β-tubulin was detected immunohistochemically in 50 specimens of premalignant lesions of the breast (ADH and Peri-PM with ADH), 50 specimens of breast in situ ductal carcinomas (DCIS), and 50 specimens of invasive ductal carcinomas (IDC). Thirty specimens of normal breast tissues served as a control group. RESULTS Immunohistochemical analysis showed that: the differences among the 4 groups (normal breast tissues, breast premalignant lesions, DCIS and IDC, P 〈 0.05) were significant, and there were also statistically significant differences between any 2 groups (P 〈 0.05) except for the β-tubulin positive expression comparing DCIS versus IDC (P 〉 0.05). In addition, β-tubulin was expressed at a higher level in Peri-PM with ADH compared to ADH (P 〈 0.05). Following the degree of breast epithelial hyperplasia involved, and its development into carcinoma, the β-tubulin positive expression displayed an elevating tendency. We also found a significant positive relationship of β-tubulin expression with lymph node metastasis (P 〈 0.05), but no significant correlation with histological grading and nuclear grade. CONCLUSION Centrosome defects may be an early event in the development of breast cancer and they can also promote tumor progression. Studies of aberrations of centrosomal proteins provide a new way to tumorigenesis. explore the mechanism of breast tumorigenesis.展开更多
Although metastatic breast cancer is considered as an incurable disease, various biological drivers influence the outcomes. The use of trastuzumab in patients overexpressing HER(human epidermal growth factor recepto...Although metastatic breast cancer is considered as an incurable disease, various biological drivers influence the outcomes. The use of trastuzumab in patients overexpressing HER(human epidermal growth factor receptor 2)-2 increases long-term survival even in those patients who developed brain metastasis. Nevertheless, special attention must be paid to the risk of cardiotoxicity. We report the case of a young woman with HER-2-positive breast cancer with bone and lung disease who developed brain metastasis during treatment with trastuzumab. The treatment has been continued and she is alive and in complete remission after 16 years.展开更多
基金Supported by Grant No.1070398 from National Fund for Development of Science and Technology,FONDECYT,Chile
文摘AIM: To determine the expression of HER2 and bradykinin B1 receptors (B1R) in the two pathogenic models of gallbladder cancer: the metaplasia dysplasia carcino ma and the adenoma carcinoma pathways.METHODS: Receptor proteins were visualized by immunohistochemistry on 5-μm sections of paraffin-embedded tissue. Expression of both receptors was studied in biopsy samples from 92 patients (6 males and 86 females; age ranging from 28 to 86 years, mean 56 years). High HER2 expression in specimens was additionally investigated by fluorescence in situ hybridization. Cell proliferation in each sample was assessed by using the Ki-67 proliferation marker.RESULTS: HER2 receptor protein was absent in adenomas and in normal gallbladder epithelium. On the contrary, there was intense staining for HER2 on the basolateral membrane of epithelial cells of intestinal metaplasia (22/24; 91.7%) and carcinoma in situ (9/10; 90%), the lesions that displayed a significantly high proliferation index. Protein up-regulation of HER2 in the epithelium with metaplasia or carcinoma in s/tu was not accompanied by HER2 gene amplification. A similar result was observed in invasive carcinomas (0/12). The B1R distribution pattern mirrored that of HER2 except that B1R was additionally observed in the adenomas. The B1R appeared either as cytoplasmic dots or labeling on the apical cell membrane of the cells composing the epithelia with intestinal metaplasia (24/24; 100%) and carcinoma in situ (10/10; 100%) and in the epithelial cells of adenomas. In contrast, both HER2 (4/12; 33%) and B1R (1/12; 8.3%) showed a low expression in inva- sive gallbladder carcinomas.CONCLUSION: The up-regulation of HER2 and B1R in precursor lesions of gallbladder carcinoma suggests cross-talk between these two receptors that may be of importance in the modulation of cell proliferation in gallbladder carcinogenesis,
文摘AIM: To examine the expression of leptin and its receptor, OB-R, in normal gastric mucosa and neoplasia. METHODS: By immunohistochemical staining using specifi c antibodies, we evaluated the expression of leptin and OB-R in 207 gastric carcinomas (100 early and 107 advanced carcinomas) and analyzed their relationship with clinicopathological features. RESULTS: Both normal gastric epithelium and carci- noma cells expressed a significant level of leptin. In cases with OB-R staining, carcinoma cells showed OB-R- positive expression, but the intensity was weaker than that in normal mucosa. The expression of OB-R showed a signifi cant correlation with the level of leptin expres- sion. The expression levels of both leptin and OB-R tend- ed to increase as the depth of tumor invasion or TMN stage increased (P < 0.01). Lymph node metastasis was detected in 49.5% (47/95) of leptin-strong cases and in 50.5% (48/95) of OB-R-positive cases, and the rate was 33% (37/112) in leptin-weak cases and 17% (19/112) in OB-R-negative cases. Both venous and lymphatic inva- sion also tended to be observed frequently in positive tumors as compared with negative tumors. Interestingly, in the 96 leptin- or OB-R-positive tumors, hematogenous metastasis was detected preoperatively in 3 (3.1%) pa- tients. In contrast, none of the carcinomas that lacked expression of leptin and OB-R showed hematogenous metastasis. CONCLUSION: Overexpression of leptin and expres- sion of OB-R may play a positive role in the process of progression in gastric cancer. Functional upregulation of leptin/OB-R may have a positive role in the development and initial phase of progression in gastric cancer.
基金Supported by Italian Ministero della Salute, IRCCS, RC0302TG13 by Ministero dell'Istruzíone, Università e Ricerca scientifica e tecnologica (MIUR), COFIN2002, to the Universita Campus Bio-Medico
文摘AIM: TO determine the DNA binding activity and protein levels of the Ku70/80 heterodimer, the functional mediator of the NHEJ activity, in human colorectal carcinogenesis. METHODS: The Ku70/80 DNA-binding activity was determined by electrophoretic mobility shift assays in 20 colon adenoma and 15 colorectal cancer samples as well as matched normal colonic tissues. Nuclear and cytoplasmic protein expression was determined by immunohistochemistry and Western blot analysis. RESULTS: A statistical found in both adenomas y significant difference was and carcinomas as compared to matched normal colonic mucosa (P〈0.00). However, changes in binding activity were not homogenous with approximately 50% of the tumors showing a clear increase in the binding activity, 30% displaying a modest increase and 15% showing a decrease of the activity.Tumors, with increased DNA-binding activity, also showed a statistically significant increase in Ku70 and Ku86 nuclear expression, as determined by Western blot and immunohistochemical analyses (P〈0.001). Cytoplasmic protein expression was found in pathological samples, but not in normal tissues either from tumor patients or from healthy subjects. CONCLUSION: Overall, our DNA-binding activity and protein level are consistent with a substantial activation of the NHEJ pathway in colorectal tumors. Since the NHEJ is an error prone mechanism, its abnormal activation can result in chromosomal instability and ultimately lead to tumorigenesis.
基金Supported by National High Technology Research and Development Program of China (2001AA218051)Educational Commission of Hubei Province of China (2005A304B09)
文摘Objective To investigate the effects of small interfering RNA (siRNA) recombinant expression vector targeting survivin gene on chemotherapy sensitivity of human colon cancer cells to 5-fluorouracil. Methods siRNA recombinant expression vector targeting survivin gene was constructed and transfected into human colon cancer cell lines LOVO. After 48 hours of transfection, cells were harvested for analysis of survivin mRNA and protein expressions using RT-PCR and Western blot. In addition, after human colon cancer cell lines were treated with Survivin siRNA and/or 5-fluorouracil, MTT assay and flow cytometry were used to analyze cell proliferation and apoptosis. Results Restriction endonuclease analysis confirmed that siRNA recombinant expression vector targeting survivin gene was successfully constructed. Inhibitory ratios of survivin mRNA and protein expressions by Survivin siRNA were 36.33% and 44.65%, respectively. Survivin siRNA combined with 5-fluorouracil significantly increased the cell proliferation inhibitory ratio and apoptosis ratio compared with 5-fluorouracil treatin~ alone (P〈0.05). Conclusion The siRNA recombinant expression vector targeting survivin gene can inhibit the expression of survivin gene, and enhance chemotherapy sensitivity of human colon cancer cells to 5- fluorouracil.
文摘AIM:To investigate the polymorphic simple sequencerepeat in intron 1 of the epidermal growth factor receptorgene(EGFR)(CA-SSRⅠ),which is known to affect theefficiency of gene transcription as a putative target of themismatch repair(MMR)machinery in colorectal tumors.METHODS:The CA-SSRⅠgenotype was analyzed ina total of 86 primary colorectal tumors,selected upontheir microsatellite instability(MSI)status[42 with highfrequency MSI(MSI-H)and 44 microsatellite stable(MSS)]and their respective normal tissue.The effect of the CA-SSRⅠgenotype on the expression of the EGFR gene wasevaluated in 18 specimens using quantitative real-timereverse transcription PCR and immunohistochemistry.RESULTS:Mutations in CA-SSRⅠwere detected in 86%(36 of 42)of MSI-H colorectal tumors and 0%(0 of 44)ofMSS tumors,indicating the EGFR gene as a novel putativespecific target of the defective MMR system(P<0.001).Impaired expression of EGFR was detected in most ofthe colorectal tumors analyzed[6/12(50%)at the mRNAlevel and 15/18(83%)at the peptide level].However,noassociation was apparent between EGFR expression andCA-SSRⅠstatus in tumors or normal tissues.CONCLUSION:Our results suggest that CA-SSRⅠsequence does not contribute to the regulation of EGFRtranscription in colon,and should thus not be consideredas a promising predictive marker for response to EGFRinhibitors in patients with colorectal cancer.
基金Supported by the National Natural Science Foundation of China, No. 39970338Shanghai Municipal Government Science and Technology Committee, No. 00JC14042and Innovation fund of Fudan University, CQF109801
文摘AIM: To investigate the regulation of phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene expression in human hepatocellular carcinoma (HCC) cell lines.METHODS: The mRNA and protein levels of PTEN were detected by Northern blot and Western blot in HCC cell lines, respectively. Plasmids containing different fragments of PTEN promoter with Luciferase reporter were constructed and transiently transfected into HCC cell lines to study the promoter activity. DNA analysis and RT-PCR were performed to detect the mutation of PTEN promoter and PTEN cDNA.RESULTS: Either protein or mRNA levels of PTEN in L02 cells (as a control) were significantly higher than that in HCC cell lines. The profile of PTEN promoter activity in 8 cell lines was closely correlated with levels of PTEN mRNA and PTEN protein. Furthermore, the sequence analysis of 8 cells lines showed no mutation in the region of PTEN promoter and PTENcDNA.CONCLUSION: PTEN expression is down-regulated in HCC cell lines probably due to loss of activity of PTEN promoter.
文摘To construct ScFv and Fab from murine anti gastric cancer monoclonal antibody(mAb)3H11. Methods.At first,3H11 ScFv and Fab were constructed with V genes PCR amplified by degenerate primers for FR1.The bacterial expressed 3H11 Ab fragments showed no antigen binding activity.Then,phage antibody library and random mutated library were constructed from 3H11 hybridoma cells and panning selection was performed.Again the identification of positive clone was failed.Finally the N terminal sequences of V regions were resumed to 3H11 original sequences by site directed mutagenesis via PCR. Results.Binding activity to gastric cancer cells was detected only from N terminal sequence corrected 3H11 ScFv and Fab,though the expression of the Ab fragments was not affected.Correction of either VL or VH N terminal sequences could partially resume the antigen binding activity. Conclusion.Sequence changes of V region N terminal introduced by PCR may seriously affect antigen binding without affecting the expression of antibody.
基金Supported by Ralph M. Parsons Foundation and Shanghai Educational Commission Grant, No. 04BC32, and Sino American Cancer Foundation
文摘AIM: To describe the significant over-expression of fibroblast growth factor receptor 3 (FGFR3), which is a signal transduction and cell proliferation related gene in hepatocellular carcinoma (HCC).METHODS: Following DNA microarray, Northern blot and quantitative real-time PCR were employed to confirm FGFR3 expression difference in HCC tissues and surrounding non-neoplastic liver tissue. FGFR3 expression levels were further determined by immunohistochemical study in 43 cases of HCC.RESULTS: Northern blot results showed the significant over-expression of FGFR3 in HCC tissues, which was consistent with that from DNA microarray. Quantitative real-time PCR demonstrated that the mean ratio of FGFR3 mRNA to glyceraldehyde-3-phosphate dehydrogenase (GADPH) mRNA in HCC tissue was 0.250, whereas the ratio in non-neoplastic liver tissue was 0.014. Statistical analyses of 43 cases of HCC revealed that HCC scored higher than the matched non-neoplastic liver tissues.Examination of clinicopathological features revealed a strong correlation of over-expression of FGFR3 with poor tumor differentiation and high nuclear grade.CONCLUSION: Over-expression of FGFR3 may play an important role in liver carcinogenesis. FGFR3 may be an ideal candidate as a molecular marker in the diagnosis of HCC and a potential therapeutic target.
文摘A recombinant plasmid containing a full length human epidermal growth factor receptor (EGFR) cDNA sequence in antisense orientation was transferred into cells of a human liver carcinoma cell line BEL-7404. Compared with the control cell clone JX-0 transferred with the vector plasmid and the parent BEL-7404 cells, the antisense EGFR transferred cell clone JX-1 showed a decreased EGFR gene expression and reduced significantly the growth potential either in anchorage-dependent or anchorage-independent growth. Furthermore. JX-1 cells appeared to be distinctly dependent on serum concentration for monolayer growth. The results suggested that antisense EGFR could partly block the EGFR gene ex-pression and reverse the malignant growth properties of human liver carcinoma cells in vitro.
基金Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan and a grant from the Ministry of Health, Labour and Welfare of Japan
文摘AIM: To examine whether lysophosphatidic acid (LPA) induces phosphorylation of c-Met and epidermal growth factor receptor (EGFR), both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 (COX-2) expression in human colon cancer cells. METHODS: Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis, followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis. RESULTS: Immunoprecipitation analysis revealed that 10 μmol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 IJmol/L LPA induced COX-2 expression in a dose-dependent manner. CONCLUSION: Our results suggest that LPA acts upstream of various receptor tyrosine kinases (RTKs) and COX-2, and thus may act as a potent stimulator of colorectal cancer. 2005 The WJG Press and Elsevier Inc. All rights reserved.
基金Supported by Doctoral Program of Higher Specialized Research Fund project (20106517110003)
文摘AIM: To investigate the expression of Toll-like receptor (TLR) 3, TLR4, TLR7 and TLR9 in esophageal squamous cell carcinoma (ESCC). METHODS: Reverse transcription-polymerase chain reaction and immunohistochemistry were used to analyze the expression of TLR3, TLR4, TLR7 and TLR9 mRNA and protein in samples from 87 esophageal cancer patients consisting of both tumor and normal tissue. RESULTS: A significant increase in TLR3, TLR4, TLR7 and TLR9 mRNA levels was detected in ESCC samples. Tumors exhibited high TLR protein expression, (70.1%, 72.4%, 66.7% and 78.2% for TLR3, TLR4, TLR7 and TLR9, respectively, P < 0.05). Nevertheless, a significant percentage of tumors also exhibited TLR4 expression in mononuclear inflammatory cells (48.3%) and TLR9 expression in fibroblast-like cells (60.9%). Tumors with high TLR3 expression in tumor cells or high TLR4 expression in mononuclear inflammatory cells were significantly associated with a higher probability of lymph node metastasis and increased depth of invasion. However, tumors with high TLR9 expression in fibroblast-like cells were associated with low probabilities of invasion and metastasis. There was no significant variation between the expression of TLR3, TLR4, TLR7 and TLR9 among different ethnic groups. CONCLUSION: TLR3, TLR4, TLR7 and TLR9 expression appears important to the biological pathogenesis of ESCC. TLRs may represent therapeutic targets for ESCC.
基金Supported by The Fundamental Research Funds for the Central Universities of China,No.20103020101000197
文摘AIM:To investigate the mechanisms of the biological roles of Dickkopf-3(Dkk-3) in cell invasion,survival and apoptosis in colon cancer cells.METHODS:Three human colon cancer cell lines,i.e.,HT-29,LoVo and SW480,were used.Overexpression of Dkk-3 induced by pEGFP-N1-Dkk-3-GFP plasmid in LoVo cells was performed using Lipofectamine 2000 reagent.Reverse transcription polymerase chain reaction and Western blotting were performed to determine the mRNA and protein expression levels of Dkk-3,respectively.Cell proliferation assay,cell cycle analysis,hoechst 33258 assay and Matrigel invasion assay were performed on Dkk-3 overexpressing transfectants.RESULTS:The mRNA and protein expressions of Dkk-3 in HT-29(mRNA:0.06 ± 0.02,protein:0.06 ± 0.01) and LoVo(mRNA:0.07 ± 0.02,protein:0.07 ± 0.02) cells were significantly lower than that in SW480 cells(mRNA:0.92 ± 0.04,protein:0.69 ± 0.13;all P < 0.05),and the greatest levels of invasiveness wasin LoVo cells.Dkk-3 overexpression inhibited the proliferation and invasion of LoVo cells and induced cell cycle arrest at G0/G1 phase and subsequent apoptosis,as indicated by increased chromatin condensation and fragments,upregulated Bax and cytochrome c protein,downregulated survivin and Bcl-2 protein,and the activation of caspase-3 and caspase-9.Furthermore,Dkk-3 overexpression reduced the accumulation of cytosolic fraction of β-catenin.CONCLUSION:Dkk-3 overexpression induced apoptosis in human colon cancer possibly through the mitochondrial pathway.Dkk-3 may be involved in the Wnt/β-catenin signaling pathways in colon cancer.
文摘AIM:To analyze the pathogenetic role and potential clinical usefulness of the epidermal growth factor receptor(EGFR)and the human epidermal growth factor receptor 2(HER2)in patients with advanced biliary tract cancer(BTC). METHODS:EGFR and HER2 expression was studied in biopsy samples from 124 patients(51%women; median age 64.8 years),with advanced BTC diagnosed between 1997 and 2004.Five micrometers sections of paraffin embedded tissue were examined by standard, FDA approved immunohistochemistry.Tumors with scores of 2+or 3+for HER2 expression on immunochemistry were additionally tested for HER2 gene amplification by fluorescence in situ hybridisation(FISH).RESULTS:34/124 patients(27.4%)had gallbladder cancer,47(37.9%)had intrahepatic BTC and 43(34.7%)had extrahepatic or perihilar BTC.EGFR expression was examined in a subset of 56 samples. EGFR expression was absent in 22/56 tumors(39.3%). Of the remaining samples expression was scored as 1+in 12(21.5%),2+in 13(23.2%)and 3+in 9(16%), respectively.HER2 expression was as follows:score 0 73/124(58.8%),score 1+27/124(21.8%),score 2+ 21/124(17%)and score 3+4/124(3.2%).HER2 gene amplification was present in 6/124,resulting in an overall amplification rate of 5%. CONCLUSION:Our data suggest that routine testing and therapeutic targeting of HER2 does not seem to be useful in patients with BTC,while targeting EGFR may be promising.
基金This work was supported by a grant from the National Natural Science Foundation of China(No.30471967)
文摘OBJECTIVE To explore the expression of β-tubulin in premalignant lesions and carcinomas of the breast, and to observe the relationship of its expression with breast cancer pathological features. METHODS The expression of β-tubulin was detected immunohistochemically in 50 specimens of premalignant lesions of the breast (ADH and Peri-PM with ADH), 50 specimens of breast in situ ductal carcinomas (DCIS), and 50 specimens of invasive ductal carcinomas (IDC). Thirty specimens of normal breast tissues served as a control group. RESULTS Immunohistochemical analysis showed that: the differences among the 4 groups (normal breast tissues, breast premalignant lesions, DCIS and IDC, P 〈 0.05) were significant, and there were also statistically significant differences between any 2 groups (P 〈 0.05) except for the β-tubulin positive expression comparing DCIS versus IDC (P 〉 0.05). In addition, β-tubulin was expressed at a higher level in Peri-PM with ADH compared to ADH (P 〈 0.05). Following the degree of breast epithelial hyperplasia involved, and its development into carcinoma, the β-tubulin positive expression displayed an elevating tendency. We also found a significant positive relationship of β-tubulin expression with lymph node metastasis (P 〈 0.05), but no significant correlation with histological grading and nuclear grade. CONCLUSION Centrosome defects may be an early event in the development of breast cancer and they can also promote tumor progression. Studies of aberrations of centrosomal proteins provide a new way to tumorigenesis. explore the mechanism of breast tumorigenesis.
文摘Although metastatic breast cancer is considered as an incurable disease, various biological drivers influence the outcomes. The use of trastuzumab in patients overexpressing HER(human epidermal growth factor receptor 2)-2 increases long-term survival even in those patients who developed brain metastasis. Nevertheless, special attention must be paid to the risk of cardiotoxicity. We report the case of a young woman with HER-2-positive breast cancer with bone and lung disease who developed brain metastasis during treatment with trastuzumab. The treatment has been continued and she is alive and in complete remission after 16 years.