Wild-type HPK1 protein expression and activation inhibits pancreatic cancer cell proliferation. A and B, Panc-1 parental, vector control, c1, c2, and m1 cells were plated at an equal density and cultured under normal conditions without MG132 treatment (A) or treated with 0.5 µmol/L MG132 (B) for the indicated time periods. Cell numbers were estimated using the MTS assays. C and D, percentages of S-phase cells in Panc-1 parental, vector control, c1, c2, and m1 cells either untreated or treated with 0.5 µmol/L MG132 for 24 h (C) or 48 h (D). Cells were plated at an equal density, and the percentage of S-phase cells was analyzed by FACS analysis. Columns, mean from three experiments.*, P < 0.05.