Fig. 4

PCBP1 suppresses cell proliferation and tumorigenesis. (a, b) Cell viability analyses of A2780 (a) and DLD-1 (b) cells stably expressing PCBP1, PCBP1-p27 KD, p27 KD or GFP control by MTT assays. Data are presented as mean±SD (**P <0.01 by a 2-tailed Student’s t test). (c) Statistical analysis of colonies induced by A2780 or DLD-1 cells overexpressing PCBP1, PCBP1-p27 KD, or GFP control in soft agar assay for anchorage-independent growth. **P <0.01, n=3, two-tailed Student’s t test. (d, e) Tumor formation induced by DLD-1 (d) and A2780 cells (e) with PCBP1 overexpression plus p27 knockdown or PCBP1 alone, respectively. Cells were injected subcutaneously into flank sides of nude mice armpit. Tumors induced were harvested and weighed at 3 weeks post-injection by A2780 cells or at 4 weeks by DLD-1 cells. The xenograft tumor weights were analyzed and shown in the lower panel, respectively, n=5. (f) Tumor formation induced by DLD-1 cells with knockdown of either p27 or PCBP1. Cells were injected subcutaneously as above. Tumors were harvested at the 3rd week, weighted and analyzed. P values are indicated, n=5