Figure 4. Knockdown of GDF15 enhances cell proliferation and invasion in human bladder carcinoma HT1376 cells.

Expressions of GDF15 in mock-knockdown HT1376 (HT-COLsi) and GDF15 knockdown HT1376 (HT-GDF15si) cells were determined by immunoblotting (a, top) and RT-qPCR (a, bottom) assays. Data are expressed as mean-fold of the GDF15 levels (±S.E.; n = 3) in relation to the HT-COLsi cell group. Proliferations of HT-GDF15si (white circle) and HT-COLsi (black circle) cells were determined according to the incorporation of ³H-thymidine (b) and MTS assays (c). Each point on the curve represents the mean-percentage (±S.E.; n = 6) of that on day 1. (d) Invasive ability of cells was determined by the in vitro matrigel invasion assays. Data are presented as mean-percentage (±S.E.) in relation to the HT-COLsi cell group. (e) Nude mice were inoculated subcutaneously with HT-COLsi (black circle) or HT-GDF15si (white circle) cells. Tumor size as measured using vernier calipers. Results are presented as tumor size in mm³ (±S.E.), which measured at the indicated time intervals. (*P < 0.05, ⁺P < 0.01).