Fig. 4

PVT1 played a vital role in cyto-protective autophagy and PDA cells growth in vitro. a MTS assay indicated that up-regulation of PVT1 enhanced cells growth in Capan-2 cells. Whereas, impairment of growth was observed after incubation with autophagy inhibitor (3-MA) (upper). Meanwhile, down-regulation of PVT1 suppressed cells growth in HPAF-II cells. However, restoration of growth occurred after treatment with autophagy inducer (rapamycin) (lower); b Colony formation assay implied that increased PVT1 expression promoted cells proliferation in Capan-2 cells. However, 3-MA diminished cells proliferation in PVT1-overexpresssed cells. On the other hand, decreased PVT1 expression inhibited cells proliferation in HPAF-II cells. But rescue of cells growth was observed after treatment with rapamycin; c Cell proliferation was investigated by EdU incorporation assays; d Cell cycle analysis indicated that the percentage of mitotic S phase cells was increased after overexpression of PVT1 in Capan-2 cells. Decreased percentage occurred after incubation with 3-MA. Decreased expression of PVT1 diminished S phase cells in HPAF-II cells. Rescue of S phase happened after induction of autophagy by rapamycin; e Apoptosis prohibited after up-regulation of PVT1 in Capan-2 cells. Inhibition of autophagy promoted apoptosis. Meanwhile, down-regulation of PVT1 contributed to apoptosis in HPAF-II cells. Autophagy induction by rapamycin diminished the effect of down-regulation of PVT1 to apoptosis. The data were represented as the means ± S.D. of three independent experiments in vitro. ^* P < 0.05 by Student’s t-test