Cytotoxic and Genotoxic Effects of Orlistat in Human Tumor Cell Lines In Vitro

Introduction: Orlistat is a widely used anti-obesity drug that acts by reversibly inhibiting gastric and pancreatic lipases in the gastrointestinal tract. Due to its widespread use and easy accessibility, concerns have been raised regarding its potential biological effects beyond its intended pharmacological action. Objective: In this context, the present study aimed to evaluate the cytotoxic and genotoxic effects of Orlistat in human tumor cell lines derived from kidney (786-O), breast (MCF-7), liver (HepG2/C3A), and neuroblastoma (SH-SY5Y), using concentrations ranging from 0.01 to 100 μg/mL at different exposure times. Materials and Methods, and Results: Cytotoxicity was assessed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay, and the results demonstrated a concentration- and time-dependent reduction in cell viability across all tested cell lines. Genotoxicity was evaluated using the comet assay, which revealed increased DNA damage in all cell models exposed to the drug. Conclusion: These findings indicate that Orlistat induces cytotoxic and genotoxic effects in different human tumor cell lines under in vitro conditions. Although the absence of nontumor cell models limits the assessment of selective toxicity, the results contribute to the understanding of its biological effects and highlight the need for further investigation.