AIM:To investigate the effect and mechanism of action of erlotinib, an epidermal growth factor receptor (EGFR) small molecule tyrosine kinase inhibitor (TKI), in the human pancreatic cancer cell line BxPC-3 both ...AIM:To investigate the effect and mechanism of action of erlotinib, an epidermal growth factor receptor (EGFR) small molecule tyrosine kinase inhibitor (TKI), in the human pancreatic cancer cell line BxPC-3 both in vitro and in vivo.METHODS: In vitro, human pancreatic cancer cell line BxPC-3 was exposed to varying concentrations of ertotinib, and its effects on proliferation, cell cycle distribution, apoptosis and the expression of proand antiapoptotic factors such as bcl-2, bcl-xl, bax and bak, and the expression of vascular endothelial cell growth factor (VEGF) were measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometric analysis, terminal deoxynucleotidyl transferase-mediated nick end labeling assay (TUNEL), and reverse transcriptionpolymerase chain reaction (RT-PCR). Potential effect of erlotinib on angiogenesis was examined by tube formation assay. Tumor growth suppression was observed in xenografted nude mice with pancreatic cancer in vivo. Immunohistochemical (IHC) staining for EGFR and factor VII-related antigen was undertaken to detect the microvessel density and VEGF expression in tumor tissue in xenograft nude mice.RESULTS: Erlotinib, as a single agent, repressed BxPC-3 cell growth in a dose-dependent manner, triggered G1 arrest and induced cell apoptosis, and suppressed capillary formation of endothelium in vitro. Expressions of VEGF were significantly down-regulated at a high concentration of 200 μmol/L, however, the expressions of bcl-2 and bcl-xl were decreased at 50 μmol/L. In vivo, Erlotinib-treated mice demonstrated a reduced tumor volume, weight and microvessel density as compared to the control. IHC staining showed decreased expression of EGFR and RT-PCR had lower VEGF expression in treated mice.CONCLUSION: The in vitro and in vivo findings provide evidence that BxPC-3 cells are inhibited with erlotinib treatment. Inhibition of EGFR may be a promising adjuvant chemotherapy strategy in pancreatic cancer treatment.展开更多
We recently reported several driver genes of biliary tract carcinoma(BTC) that are known to play important roles in oncogenesis and disease progression. Although the need for developing novel therapeutic strategies is...We recently reported several driver genes of biliary tract carcinoma(BTC) that are known to play important roles in oncogenesis and disease progression. Although the need for developing novel therapeutic strategies is increasing, there are very few BTC cell lines and xenograft models currently available for conducting preclinical studies. Using a total of 88 surgical BTC specimens and 536 immunodeficient mice, 28 xenograft models and 13 new BTC cell lines, including subtypes, were established. Some of our cell lines were found to be resistant to gemcitabine, which is currently the first choice of treatment, thereby allowing highly practical preclinical studies to be conducted. Using the aforementioned cell lines and xenograft models and a clinical pathological database of patients undergoing BTC resection, we can establish a preclinical study system and appropriate parameters for drug efficacy studies to explore new biomarkers for practical applications in the future studies.展开更多
文摘AIM:To investigate the effect and mechanism of action of erlotinib, an epidermal growth factor receptor (EGFR) small molecule tyrosine kinase inhibitor (TKI), in the human pancreatic cancer cell line BxPC-3 both in vitro and in vivo.METHODS: In vitro, human pancreatic cancer cell line BxPC-3 was exposed to varying concentrations of ertotinib, and its effects on proliferation, cell cycle distribution, apoptosis and the expression of proand antiapoptotic factors such as bcl-2, bcl-xl, bax and bak, and the expression of vascular endothelial cell growth factor (VEGF) were measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometric analysis, terminal deoxynucleotidyl transferase-mediated nick end labeling assay (TUNEL), and reverse transcriptionpolymerase chain reaction (RT-PCR). Potential effect of erlotinib on angiogenesis was examined by tube formation assay. Tumor growth suppression was observed in xenografted nude mice with pancreatic cancer in vivo. Immunohistochemical (IHC) staining for EGFR and factor VII-related antigen was undertaken to detect the microvessel density and VEGF expression in tumor tissue in xenograft nude mice.RESULTS: Erlotinib, as a single agent, repressed BxPC-3 cell growth in a dose-dependent manner, triggered G1 arrest and induced cell apoptosis, and suppressed capillary formation of endothelium in vitro. Expressions of VEGF were significantly down-regulated at a high concentration of 200 μmol/L, however, the expressions of bcl-2 and bcl-xl were decreased at 50 μmol/L. In vivo, Erlotinib-treated mice demonstrated a reduced tumor volume, weight and microvessel density as compared to the control. IHC staining showed decreased expression of EGFR and RT-PCR had lower VEGF expression in treated mice.CONCLUSION: The in vitro and in vivo findings provide evidence that BxPC-3 cells are inhibited with erlotinib treatment. Inhibition of EGFR may be a promising adjuvant chemotherapy strategy in pancreatic cancer treatment.
文摘We recently reported several driver genes of biliary tract carcinoma(BTC) that are known to play important roles in oncogenesis and disease progression. Although the need for developing novel therapeutic strategies is increasing, there are very few BTC cell lines and xenograft models currently available for conducting preclinical studies. Using a total of 88 surgical BTC specimens and 536 immunodeficient mice, 28 xenograft models and 13 new BTC cell lines, including subtypes, were established. Some of our cell lines were found to be resistant to gemcitabine, which is currently the first choice of treatment, thereby allowing highly practical preclinical studies to be conducted. Using the aforementioned cell lines and xenograft models and a clinical pathological database of patients undergoing BTC resection, we can establish a preclinical study system and appropriate parameters for drug efficacy studies to explore new biomarkers for practical applications in the future studies.