To examine whether XZH-5 may inhibit STAT3 phosphorylation in breast cancer and pancreatic cancer cells expressing persistently activated STAT3, MDA-MB-231, SUM159, PANC-1, and SW1990 cells were treated with two different concentrations of XZH-5 as indicated for 8 hours. This evidence concerns the gene STAT3 and familial pancreatic carcinoma.