Figure 2

OCT4 promotes tumor formation by cervical cancer cells in vivo. (a) OCT4 expression in cervical cancer cell lines was detected by immunocytochemistry and the positive rates were summarized. The arrow indicates the OCT4 positive cell. (b) OCT4 expression in cervical cancer cell lines was detected by western blotting. (c) Western blot analysis of OCT4 protein and in HeLa and SiHa parental, control- and OCT4-stably transfected cells. For western blot analyses, Tera-1 cells were used as a positive control, and β-actin served as the loading control. A tumor formation assay was performed with three mice per group. Tumor growth curves were calculated based on monitoring performed every 4 days post-transplant. At 36 days post-transplant for HeLa cells (d) and 32 days post-transplant for SiHa cells (e), the xenograft tumors were dissociated and weighed (f and g). The data were analyzed and shown as mean±S.E.M. (d and e were determined by two-way ANOVA test, *P<0.05 whereas f and g were determined by Student’s t-test). (h) Serial sections of immunochemical staining for OCT4 and Ki-67 in indicated tumor xenografts. Scale bar=20 μm