Figure 6

Specific knockdown of Cyp1b1 expression renders cholangiocarcinoma cells more susceptible to chemotherapeutic agents. Mz-ChA-1 cells were stably transfected with Cyp1b1 shRNA vectors. The expression of Cyp1b1 was assessed in the mock-transfected cell line (Mz-Neo Neg) and the cell line containing the Cyp1b1 shRNA (Mz-Cyp1b1 shRNA) real-time PCR and immunoblotting (a). Data are expressed as average±s.e.m. after correction for GAPDH expression or β-actin, respectively. ^* denotes significance (P<0.05) from Mz-ChA-1 cells. The effect of chemotherapy treatment on cell proliferation was assessed by MTS assays (b). The three cell lines (Mz-ChA-1, Mz-Neo Neg, and Mz-Cyp1b1 shRNA) were treated with 5-FU (10–30 μM), gemcitabine (10–30 μM), or mitomycin C (1–10 μM) for 48 h and data are expressed as fold change in proliferation (average±s.e.m., n=7). ^* denotes P<0.05 compared with basal treatment within each cell line and # denotes significance compared with the effects of these chemotherapeutic agents compared with Mz-ChA-1 cells.