Cannabidiol and tetrahydrocannabinol in ovarian cancer: A systematic review and Meta-analysis of anticancer efficacy

Abstract Introduction Ovarian cancer is the third most common gynecological-related malignancy worldwide, with limited therapeutic options due to late diagnosis, increased rates of recurrence, and chemoresistance. Emerging evidence suggests that cannabidiol (CBD) and tetrahydrocannabinol (THC) exhibit anticancer properties through modulation of key signaling pathways. This systematic review and meta-analysis aimed to quantify the anti-neoplastic effects of CBD and THC in ovarian cancer models and to elucidate the mechanistic pathways underlying these actions. Content Following PRISMA guidelines, we searched PubMed, Embase, Web of Science, and Google Scholar through October 2025. Eligible studies were in vitro or in vivo experiments assessing CBD or THC on ovarian cancer models. Primary outcomes were overall anti-tumor response (cell viability), total apoptosis, G0/G1 cell-cycle arrest, and reactive oxygen species (ROS) levels. Data were pooled using random-effects models, estimating Standardized Mean Differences (SMDs) with 95 % confidence intervals (CIs). Twelve studies met the inclusion criteria. Both cannabinoids demonstrated robust anti-proliferative effects (CBD: SMD = −9.68, 95 % CI: [-12.64, −6.72]; THC: SMD = −7.84, 95 % CI: [-11.46, −4.23]). Mechanistically, CBD and THC significantly induced total apoptosis (SMD=2.57 and 4.43, respectively) and G0/G1 cell-cycle arrest (SMD=1.58 and 4.43, respectively). Both compounds also markedly elevated intracellular ROS (SMD=4.02 and 8.85, respectively). Data for THC mechanistic outcomes were limited. Egger’s test indicated potential publication bias (p