Anticancer activity of Lavandula stoechas L. flower ethanolic extract through apoptotic pathway modulation in colorectal cancer cells

This study aimed to investigate the anticancer effects and underlying mechanisms of an ethanolic extract of Lavandula stoechas L. flowers (LsHE) on colorectal cancer. The extract demon strated high phenolic content (230.31 ± 11.28 mg GAE g^–¹ dm) and strong antioxidant activity. HPLC analysis identified rosmarinic acid and quercetin as major constituents. HT-29 colorectal carcinoma cells and HEK-293 healthy kidney epithelial cells were treated with LsHE for 48 h. The concentration of LsHE required to inhibit 50 % of HT-29 cell viability was found to be 86.37 ± 3.07 µg mL^–1, whereas a higher concentration of 131.30 ± 9.33 µg mL^–1 was observed for HEK-293 cells. In HT-29 cells, flow cytometry analysis revealed increased early (9.7 %) and late (6.8 %) apoptotic populations following LsHE treatment (p < 0.0001). qRT-PCR analysis showed significant upregulation of TP53 and CASP3 compared to the untreated group (p < 0.05 and p < 0.01, resp.), while BAX expression was unexpectedly downregulated. These findings suggest that LsHE may trigger caspase-3-dependent apoptosis through a p53-mediated mechanism, potentially independent of the BAX/BCL-2 pathway. In conclusion, the present in vitro study highlights the potential of LsHE as a natural agent that still exerts some cytotoxicity toward normal epithelial cells and pro-apoptotic activity in colorectal cancer cells. Our findings provide a molecular basis for further in vivo studies to evaluate the possible therapeutic potential and mechanistic relevance of LsHE in CRC chemoprevention.