Therapeutic Potential of Natural Xanthones Against Prostate Adenocarcinoma: A Comprehensive Review of Research Trends During the Last Ten Years (2014–2024)

Prostate cancer is the most common cancer diagnosed in men worldwide and is ranked as the fifth leading cause of cancer-related death in men globally. Background/Objectives: We aimed to identify the effectiveness of cytotoxic plant-derived xanthones against prostate cancer over the past ten years. Methods: Searches were performed in Google Scholar, Web of Science, Scopus and PubMed/Medline for ten years up to December 2024 using pre-defined inclusion and exclusion criteria. The published articles were assessed in accordance with the PRISMA 2020 procedure. Results: From a total number of n = 11,932 results, 9 were retained as included studies, which included 51 xanthones. Conclusions: Garcibractatin A and bracteaxanthone VII exhibited significant cytotoxic effects on human prostate cancer (PC-3 cells) [IC50 value of 2.93 and 4.8 μM] and the human normal prostatic stromal myofibroblast cell line (WPMY-1 cells) [IC50 value of 0.76 and 3.2 μM], which were more potent than the reference etoposide [(IC50 value of 10.07 μM) and (IC50 value of 12.98 μM)]. Parvifolixanthone A showed significant activity on PC-3 (IC50 of 4.65 μM), which was more potent than the reference 5-fluorouracil (IC50 of 30.59 μM); gaudichaudione H, cantleyanone A, isobractatin, isoforbesione, and neobractatin had strong cytotoxicity (IC50 values between 2.10 and 3.39 μM) as compared to etoposide (IC50 of 10.07 μM). Despite these positive outlooks, there are still several restrictions, most notably the absence of in vivo evidence in many studies and well-defined mechanisms of action for all the promising bioactive xanthones identified in this work as well as the absence of studies of their cytotoxicity on certain normal cells.