Limonoid compounds from Xylocarpus granatum and their anticancer activity against esophageal cancer cells

BACKGROUND: To investigate the anticancer effects of limonoid compounds that were isolated and purified from Xylocarpus granatum fruits on human esophageal cancer (EC) cells. A structure‐activity relationship experiment was designed to identify the functional moiety of limonoid compounds identified as being critical for its anticancer activity. METHODS: Eca109 cells were cultured in RPMI1640 medium and treated with limonoid compounds. Cell proliferation was determined by the MTT assay in vitro. Eca109 cells apoptosis was analyzed by by flow cytometry after being treated with xylogranatin C. The expression of p53, Bax, bcl‐2, caspase‐3 and GRP78 in Eca109 cells after xylogranatin C treatment was examined by western blot assay. RESULTS: Four linonoid compounds strongly inhibited the cellular proliferation of Eca109 cells. Xylogranatin C was the strongest inhibitor, whose inhibitory effect was comparable to that of the well‐known chemotherapeutic agent, cisplatin. Furthermore, xylogranatin C might induce Eca109 cell apoptosis through joint effects on multiple pathways, including the death receptor and endoplasmic reticulum pathways. Additionally, xylogranatin C suppressed tumor cell proliferation by upregulating miR‐203a expression in Eca109 cells. CONCLUSIONS: Xylogranatin C induced Eca109 cellular apoptosis and exerted antitumor activity. Xylogranatin C suppressed tumor cell proliferation by upregulating miR‐203a expression in Eca109 cells.