Fig. 6

Knockdown of PVT1 prohibited PDA growth in vivo. a Down-regulation of PVT1 in HPAF-II cells inhibited tumor growth after 4 weeks in vivo (n = 5 per group). Upper: negative control group. Lower: knockdown groups formed in nude mice subcutaneously injected with PVT1-silencing HPAF-II cells; b, c Growth curves (b) and tumor weight (c) of xenograft tumors after subcutaneous injection with PVT1-silencing HPAF-II cells. The tumor volumes were investigated every week after injection with PVT1-silencing HPAF-II cells (n = 5). Diminished expression of PVT1 markedly attenuated the tumor growth in PDA; d, e Representative images (d) and photon influx (e) of xenograft tumors after subcutaneous injection with PVT1-silencing HPAF-II cells by IVIS (n = 5 per group). f Representative images of HE staining, TUNEL, immunohistochemical staining of Ki67 and ULK1; g-i The quantitation of Ki67 (g), TUNEL (h) and ULK1 (i) was calculated. Immunohistochemical staining of Ki67 and ULK1 showed that decreased expression of PVT1 led to suppression of Ki67 proliferation index and ULK1 expression, while TUNEL positive cells were increased. The data were represented as the mean ± S.D. (n = 5). ^* P < 0.05, ^** P < 0.01 and ^*** P < 0.001 by Student’s t-test