CCN4 and polyarteritis nodosa: Firstly, lentivirus-mediated mouse WISP1-overexpression vector or control was stably transduced into SH-PAN cells (SH-PAN-lent-WISP1 and SH-PAN-lent-ctr) and lentivirus-mediated human WISP1-silencing vector or control was stably transduced into Panc-1 cells (Panc-1-lent-WISP1i and Panc-1-lent-ctr) and MIA PaCa-2 cells (MIA PaCa-2-lent-WISP1i and MIA PaCa-2-lent-ctr).