Apoptotic Gene Expression in HepG2 Cells Treated with Ornithogalum sigmoideum and Smilax excelsa Compounds

The present study investigates the pro- and anti-apoptotic responses of HepG2 liver cancer cells to Ornithogalum sigmoideum (O. sigmoideum) and Smilax excelsa (S. excelsa) extracts, aiming to identify their potential as anti-cancer agents. Methanolic extracts of O. sigmoideum and S. excelsa were prepared, and their phytochemical profiles were analyzed by Gas Chromatography–Mass Spectrometry (GC-MS). Cytotoxicity and IC50 values were determined in HepG2 cells using the MTT assay. The relative mRNA expression of apoptotic genes (BAX, BCL-2, and Caspase-3) was quantified by qPCR, and the treatment effect size was calculated using Cohen’s d. GC-MS analysis revealed distinct phytochemical profiles; S. excelsa was rich in phenolic compounds, while fatty acid esters and alcohols dominated Ornithogalum extracts. O. sigmoideum bulb extract exhibited the strongest cytotoxicity (IC50 = 125.57 µg/mL), followed by the leaves (IC50 = 156.43 µg/mL), whereas Smilax showed minimal toxicity (IC50 = 304.15 µg/mL). Mechanistically, the O. sigmoideum leaf extract showed gene expression patterns consistent with pro-apoptotic signaling, including upregulation of BAX and Caspase-3 mRNA. O. sigmoideum extracts, especially from leaf parts, exhibit significant cytotoxicity, and the transcriptomic profile is consistent with apoptotic pathway activation in HepG2 cells, positioning it as a candidate for further mechanistic investigation.