Proteomic profiling of cholangiocarcinoma cell line treated with pomiferin from Derris malaccensis.

Pomiferin, a prenylated isoflavonoid from Derris malaccensis with strong anti-fungal and anti-oxidant activities, showed cytotoxic activity towards human cholangiocarcinoma cells (HuCCA-1), with IC(50) of 0.9 microg/mL. Pomiferin caused apoptosis, detectable by DNA fragmentation. Two-dimensional PAGE showed increased expression of 12 proteins, namely glucose-regulated protein 75 (grp 75), calcyclin (S100A6), degraded cytokeratin 19, ATP synthase D, ribosomal protein P0, degraded cytokeratin 18 (two spots pI/MW 6.03/29.9 and pI/MW 4.66/21.5), cofilin, annexin A1, triose phosphate isomerase, peroxiredoxin-1, calgizzarin, and profilin. In contrast, cytokeratins (CK) 7, 18 and 19 were down-regulated, and were shown by 1-DE immunodetection to be degraded.