Feasibility evaluation of emodin (rhubarb extract) as an inhibitor of pancreatic cancer cell proliferation in vitro.

Emodin is a commonly used traditional herbal treatment in China, including use for pancreatic malignancy. In this study, the potential for emodin to inhibit pancreatic cancer cell proliferation was examined using 4 human pancreatic adenocarcinoma cell lines: Mia Paca-2, BxPC-3, Panc-1, and L3.6pl. WST-1 proliferation, propidium iodide flow cytometry cell cycle analysis, and poly-ADP-ribose polymerase (PARP) Western blot analysis were performed. Forty-eight-hour treatment with 50 muM emodin inhibited proliferation in Mia Paca-2 cells by 42%, BxPc-3 by 38%, L3.6pl by 56%, and Panc-1 by 18% (all P < .01). In three-fourths of the cell lines, emodin treatment resulted in an increase (from 4.7% to 22%) in the cell population number in apoptosis when measured by flow cytometric analysis. Mia Paca-2 revealed a significant PARP cleavage product when compared with control. These feasibility experiments provide initial evidence that emodin exerts an antiproliferative effect, likely through apoptosis induction-related mechanism(s), that is reproducible in various human pancreatic cancer cell lines.