In Vitro Evaluation of Cytotoxic Potential of Caladium lindenii Extracts on Human Hepatocarcinoma HepG2 and Normal HEK293T Cell Lines

Abstract

Data regarding the therapeutic potential of Caladium lindenii (C. lindenii) are insufficient. It becomes more important to explore plants as an alternative or palliative therapeutics in deadly diseases around the globe. The current study was planned to explore C. lindenii for its anticancer activity of ethanolic and hexane extracts of C. lindenii leaves against hepatic carcinoma (HepG2) and human embryonic kidney (HEK293T) cell lines. HepG2 and HEK293T cells were treated with 10, 50, 100, 200, and 400 μg/mL of ethanolic and hexane extracts of C. lindenii and were incubated for 72 h. Antiproliferative activity was measured by 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assay, and percentage viability were calculated through crystal violet staining and cellular morphology by Floid Cell Imaging Station. The study showed ethanolic extract exhibiting a significantly higher antiproliferative effect on HepG2 ( $\text{IC}50=31$ μg/mL) in a concentration-dependent manner, while HEK293T ( $\text{IC}50=241$ μg/mL) cells showed no toxicity. Hexane extract exhibited lower cytotoxicity ( $\text{IC}50=150$ μg/mL) on HepG2 cells with no effect on HEK293T ( $\text{IC}50=550$ μg/mL). On the other hand, the percentage viability of HepG2 cells was recorded as 78%, 67%, 50%, 37%, and 28% by ethanolic extracts, and 88%, 80%, 69%, 59%, and 50% by hexane extracts at tested concentrations of both extracts. Toxicity assay showed significantly safer ranges of percentage viabilities in normal cells (HEK293T), i.e., 95%, 90%, 88%, 76%, and 61% with ethanolic extract and 97%, 95%, 88%, 75%, and 62% with hexane extract. The assay validity revealed 100% viability in the control negative (dimethyl sulfoxide treated) and less than 45% in the control positive (cisplatin) on both HepG2 and HEK293T cells. Morphological studies showed alterations in HepG2 cells upon exposure to >50 μg/mL of ethanolic extracts and ≥400 μg/mL of hexane extracts. HEK293T on the other hand did not change its morphology against any of the extracts compared to the aggressive changes on the HepG2 cell line by both extracts and positive control (cisplatin). In conclusion, extracts of C. lindenii are proved to have significant potential for cytotoxicity-induced apoptosis in human cancer HepG2 cells and are less toxic to normal HEK293T cells. Hence C. lindenii extracts are proposed to be used against hepatocellular carcinoma (HCC) after further validations.