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Objective To analyze how the infection of human papillomavirus 16 (HPV16) affects expression of DNA polymerase β ( DNA polB ) with the aim of probing the mechanism of over-expression of DNA polB in human cancers.Methods Four fragments of human DNA polB promoter were amplified and constructed into luciferase reporter vector pGL-Basic, generating pGL-BP, pGL-BMH, pGL-BMS, and pGL-BAT constructs respectively, and cotransfected with HPVI6 or HPV6 into Hep2 cells. Luciferase activity was assayed 48 hours after transfection. Semi-quantitative RT-PCR was used to measure mRNA expression of endogenous DNA polB. Immunohistochemistry and/n situ hybridization were used to analyze DNA polB expression and HPV16 or HPV6 infection in 38 cases of cervical lesions respectively.Results With co-transfection of HPV16 and DNA polB promoter-driving reporters into Hep2 cells, pGL-BP re-porter in full-length DNA polB promoter presented markedly elevated luciferase activities ( P < 0. 05 ). However, the other three mutant reporters: pGL-BMH, pGL-BMS, and pGL-BAT, generated no reporting activities in the presence of HPV16 ( P > 0. 05 ). On the contrary, all of polB promoter reporters were little stimulated in co-transfection of HPV6 (P > 0. 05 ). The transfection of HPV16 could enhance the endogenous polB mRNA expression compared with that of HPV6 (3.42 vs. O. 80, P