目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增...目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增CASp并克隆至真核报告载体pCAT3-Basic中,构建pCAT3-CASp报告载体。分别以该质粒单独或与pcDNA3.1(-)-RH共转染肝癌细胞系HepG2细胞,ELISA法检测氯霉素乙酰转移酶(CAT)的表达活性,并以pCAT3-Basic空载体、pCAT3-TXNRD1p分别转染HepG2细胞作为阴性和阳性对照。结果pCAT3-CASp和pcDNA3.1(-)-RH瞬时共转染的HepG2细胞的CAT表达活性是pCAT3-CASp的1.5倍,是pCAT3-Basic空载体的2.7倍。结论本实验进一步验证了我室利用基因表达谱技术研究RNase H蛋白反式激活作用的结果。我室克隆的CAS启动子具有顺式激活下游基因的活性;HBV的RNase H蛋白具有对CAS的反式激活作用。展开更多
凋亡蛋白抑制因子(inhibitor of apoptosis protein,IAP)是一类重要的抗细胞凋亡因子,与肿瘤的发生和发展密切相关.Livin是新近发现的IAP家族成员,主要通过抑制Caspases途径等机制发挥强大的抗凋亡能力,不仅特异性高表达于人的胚胎组...凋亡蛋白抑制因子(inhibitor of apoptosis protein,IAP)是一类重要的抗细胞凋亡因子,与肿瘤的发生和发展密切相关.Livin是新近发现的IAP家族成员,主要通过抑制Caspases途径等机制发挥强大的抗凋亡能力,不仅特异性高表达于人的胚胎组织及大多数人类肿瘤组织,在一些非肿瘤性疾病中也发现其异常表达.下调Livin的表达能够增加细胞凋亡率、抑制肿瘤生长和增加肿瘤细胞对化疗药物的敏感性.Livin的特异性表达有可能为这些疾病的早期诊断和基因、蛋白、免疫靶向治疗提供新方向.展开更多
Objective The cellular apoptosis susceptibility(CAS) protein plays a regulatory role in the induction of cell death in tumor cells. The objective of this study was to investigate the association of the expression of C...Objective The cellular apoptosis susceptibility(CAS) protein plays a regulatory role in the induction of cell death in tumor cells. The objective of this study was to investigate the association of the expression of CAS protein with HBV infection in the development of HCC. Methods The expression level of CAS was measured with immunohistochemistry. The occurrence of HBs Ag, HBe Ag and HBV DNA in HCC were concurrently examined with immunohistochemistry and in situ hybridization, respectively. Results The results showed that the CAS protein was detected in 86%(43/50), 70%(7/10), 15%(3/20) and none(0/20) of livers from patients with HCC, cholangiocarcinoma, cirrhosis and hepatitis, respectively. Furthermore, the level of CAS protein was higher in poorly differentiated tumors than moderately or well differentiated HCC. Interestingly, the CAS was stained significantly stronger in HBV-infected HCC than in non-HBV infected tissues(P < 0.01). Conclusions The expression of CAS is facilitated by HBV infection in HCC, suggesting that CAS might be a prognostic marker and a putative therapeutic target for HCC.展开更多
文摘目的探讨乙型肝炎病毒DNA多聚酶(HBV DNA P)结构域蛋白RNase H对细胞凋亡易感基因(CAS)的转录激活作用。方法以HBV DNA P结构域蛋白RNase H的反式调节因子的基因表达谱芯片结果为基础,利用生物信息学技术确定CAS的启动子区域(CASp),扩增CASp并克隆至真核报告载体pCAT3-Basic中,构建pCAT3-CASp报告载体。分别以该质粒单独或与pcDNA3.1(-)-RH共转染肝癌细胞系HepG2细胞,ELISA法检测氯霉素乙酰转移酶(CAT)的表达活性,并以pCAT3-Basic空载体、pCAT3-TXNRD1p分别转染HepG2细胞作为阴性和阳性对照。结果pCAT3-CASp和pcDNA3.1(-)-RH瞬时共转染的HepG2细胞的CAT表达活性是pCAT3-CASp的1.5倍,是pCAT3-Basic空载体的2.7倍。结论本实验进一步验证了我室利用基因表达谱技术研究RNase H蛋白反式激活作用的结果。我室克隆的CAS启动子具有顺式激活下游基因的活性;HBV的RNase H蛋白具有对CAS的反式激活作用。
文摘凋亡蛋白抑制因子(inhibitor of apoptosis protein,IAP)是一类重要的抗细胞凋亡因子,与肿瘤的发生和发展密切相关.Livin是新近发现的IAP家族成员,主要通过抑制Caspases途径等机制发挥强大的抗凋亡能力,不仅特异性高表达于人的胚胎组织及大多数人类肿瘤组织,在一些非肿瘤性疾病中也发现其异常表达.下调Livin的表达能够增加细胞凋亡率、抑制肿瘤生长和增加肿瘤细胞对化疗药物的敏感性.Livin的特异性表达有可能为这些疾病的早期诊断和基因、蛋白、免疫靶向治疗提供新方向.
文摘Objective The cellular apoptosis susceptibility(CAS) protein plays a regulatory role in the induction of cell death in tumor cells. The objective of this study was to investigate the association of the expression of CAS protein with HBV infection in the development of HCC. Methods The expression level of CAS was measured with immunohistochemistry. The occurrence of HBs Ag, HBe Ag and HBV DNA in HCC were concurrently examined with immunohistochemistry and in situ hybridization, respectively. Results The results showed that the CAS protein was detected in 86%(43/50), 70%(7/10), 15%(3/20) and none(0/20) of livers from patients with HCC, cholangiocarcinoma, cirrhosis and hepatitis, respectively. Furthermore, the level of CAS protein was higher in poorly differentiated tumors than moderately or well differentiated HCC. Interestingly, the CAS was stained significantly stronger in HBV-infected HCC than in non-HBV infected tissues(P < 0.01). Conclusions The expression of CAS is facilitated by HBV infection in HCC, suggesting that CAS might be a prognostic marker and a putative therapeutic target for HCC.