Antiproliferative and apoptosis-inducing effects of Peganum harmala L. seed extracts on gastric adenocarcinoma

Introduction: Gastric cancer treatment remains challenging due to side effects and limited options. This study investigated Peganum harmala L., a traditional medicinal plant with anticancer alkaloids, by evaluating its crude extract and fractions for antiproliferative, apoptotic, and cell cycle effects on human gastric adenocarcinoma (AGS) cells. Methods: Fractionation of the crude hydroalcoholic extract was done using solvents of varying polarity (chloroform, ethyl acetate, n-butanol, and n-hexane). Antiproliferative effects were assessed via MTT assay at five concentrations (۰-۲۰۰ µg/mL) on AGS and human dermal fibroblast (HDF) cells. Apoptosis and cell cycle were conducted via flow cytometric technique after ۴۸ h treatment by annexin V-FITC/propidium iodide binding and propidium iodide intercalation into nuclear DNA, respectively. Results: The crude extract and three fractions (chloroform, n-butanol, ethyl acetate) showed selective cytotoxicity against AGS cells versus HDFs (P<۰.۰۵). The n-butanol fraction indicated the highest potency compared to the crude extract and other fractions (P<۰.۰۵). Apoptosis analysis via flow cytometry indicated a noticeable increase in apoptosis in AGS cells treated with P. harmala crude extract, compared to untreated cells (P<۰.۰۵). Flow cytometric analysis revealed that both the crude extract and n-butanol fraction significantly arrested cells in the G۲/M phase while reducing the G۱ phase population (P<۰.۰۵). Conclusion: P. harmala seed extracts demonstrate significant, selective antiproliferative effects on gastric cancer cells, mediated partly through the induction of apoptosis and arresting the cell cycle in G۲/M phase. These findings validate traditional uses and highlight the n-butanol fraction as particularly promising for further anticancer development.