Screening of Antiproliferation Activity of Thai Medicinal Plants Against Human Cholangiocarcinoma Cells in Vitro

Abstract

Cholangiocarcinoma is a serious public health concern in Thailand with increasing
incidence and mortality rates. The present study aimed to investigate antiproliferation
activity of crude ethanolic extracts of 28 plants and 5 recipes used in Thai folklore medicine
against human cholangiocarcinoma (CL-6) and human hepatocarcinoma (HepG2) cell lines in
vitro. Antiproliferation activity of the plant extracts against the cancerous cell lines compared
with normal cell line (renal epithelial cell) was assessed using MTT assay and the IC50
(concentration which inhibits cell growth by 50%) were calculated. The extracts from eight
plants and one folklore recipe exhibited promising activity against the cholangiocarcinoa CL-
6 cell line with percentage cell survival of less than 50% at the concentration of 50 μg/ml.
Among these, the extracts from the five plants and one recipe (AtLEt, KaGEt, ZiOEt, PiCEt,
MeFEt and PsPyEt) showed potent cytotoxic activity with mean IC50 values of 24.09, 37.36,
34.26, 40.74, 48.23 and 44.12 μg/ml, respectively. In contrast, activities against the
hepatoma cell HepG2 varied markedly; mean IC50 ranged from 9.67 to 115.47 μg/ml and the
only promising extract was from ZiOEt (IC50 9.67 μg/ml). The sensitivity of all the three cells
to 5-FU also varied according to cell types, particularly with CL-6 cell (IC50 757 μM). In
overall, it can be concluded that ethanolic extracts of AtLEt and ZiOEt contained
antiproliferation against CL-6 and Hep-G2 cell line, respectively.