Anticancer Mechanisms of Bioactive Compounds from Sweet Potato (Ipomoea batatas L.) Leaves: A Systematic Review

Sweet potato leaves (SPL) are increasingly recognized as a significant source of nutritionally and pharmacologically important bioactive compounds. This systematic review critically synthesizes current in vitro, in vivo, and preclinical data to evaluate the cancer preventive properties of SPL, with emphasis on their phytochemical composition, molecular mechanisms, and therapeutic relevance. A comprehensive literature search across major scientific databases (2015-2025), guided by PRISMA methodology, initially identified 29,416 records. After applying pre-specified inclusion and exclusion criteria and screening titles, abstracts, and full-texts, 38 eligible studies were included. The compiled evidence demonstrates that SPL contains high concentrations of phenolic acids, flavonoids, peptides, carotenoids, and dietary fiber, all of which contribute to diverse anticancer activities. Reported mechanisms include apoptosis induction, cell-cycle arrest, limitation of tumor propagation and metastatic activity, regulation of oncogenic pathways (PI3K/Akt, MAPK, NF-κB), modulation of inflammatory mediators, and suppression of angiogenesis. These effects were observed across multiple cancer models, including liver, colon, breast, lung, and prostate cancers. In addition, SPL represents a promising natural source of anticancer agents, significant gaps remain, particularly regarding standardized extraction procedures, phytochemical characterization, bioavailability, and human clinical validation. Overall, this review underscores SPL as a sustainable and underutilized plant resource with potential applications in functional foods, nutraceuticals, and adjunctive cancer therapy, while highlighting the need for mechanistic studies, pharmacokinetic investigations, and well-designed clinical trials to support future translational development.