Effect of Hematopoietic Pre-B-cell Leukemia Transcription Factor Interacting Protein Knockdown on Proliferation,Cell Cycle and Apoptosis in Pancreatic Cancer Cells

Abstract

Objective To unravel the role of hematopoietic pre-B-cell leukemia transcription factor interacting protein(HPIP)in the proliferation,cell cycle,and apoptosis of pancreatic ductal adenocarcinoma(PDAC)cells. Methods The HPIP expression in PDAC tissue was determined by immunohistochemical staining.Knockdown of HPIP was accomplished in MIA PaCa-2 and BxPC-3 cell lines by transient transfection of HPIP siRNA and validated by Western blotting.Cell proliferation was assessed using the cell counting kit-8 assay and colony formation assay.Cell cycle and apoptosis were detected by flow cytometry.Western blotting was performed to detect the expression levels of cyclin D1,caspase 7,and cleaved caspase 7. Results HPIP was overexpressed in PDAC tissue compared with matched adjacent pancreatic tissue(Z=-2.060,P=0.039).Knockdown of HPIP inhibited the proliferation of MIA PaCa-2 and BxPC-3 cells(all P<0.05).Knockdown of HPIP significantly reduced the positive colonies formed by MIA PaCa-2 and BxPC-3 cells(t=4.706,P=0.009;t=9.514,P=0.000).Knockdown of HPIP decreased the proportion of S phase cells(t=7.642,P=0.001;t=2.714,P=0.051)and increased the proportion of G0/G1 phase cells(t=3.244,P=0.031;t=6.095,P=0.003)in MIA PaCa-2 and BxPC-3 cells.Meanwhile,knockdown of HPIP increased the proportions of late-phase MIA PaCa-2 and BxPC-3 cells(t=24.58,P=0.000;t=36.45,P=0.000)and the overall apoptosis rate(t=29.43,P=0.000;t=43.52,P=0.000).In MIA PaCa-2 and BxPC-3 cells,knockdown of HPIP decreased the expression level of cyclin D1(t=6.705,P=0.002;t=6.238,P=0.003)and increased the expression level of cleaved caspase 7(t=3.991,P=0.016;t=6.536,P=0.002). Conclusions HPIP is overexpressed in PDAC tissue.Knockdown of HPIP inhibits the proliferation and G0/G1 to S transition of PDAC cells.Meanwhile,knockdown of HPIP promotes the apoptosis of PDAC cells.Thus,HPIP may act as an oncogene in PDAC.