Anthocyanins: From Natural Colorants to Potent Anticancer Agents

Cancer is a prevalent global disease affecting ~20 million individuals, and this burden causes the death of ~9.7 million people in 2024. The prevalence rate is continuously increasing due to exposure to harmful environmental and occupational contaminants (toxins and chemicals), compromised immune response, genetic modifications, and poor lifestyle and dietary practices. The management of cancer is challenging and demands cost-effective and safe therapeutic strategies. This review accentuates the anticancer potential of anthocyanins and its associated underlying mechanism. Anthocyanins, the active components extracted from grapes, berries, black chokeberries, eggplants, black currants, sweet cherries, strawberries, black grapes, plums, and red onions, hold antioxidant and anti-inflammatory potential. The bioavailability of anthocyanins is a crucial factor in imposing their anticancer effect, and this bioavailability can be improved by microbial phenolic catabolites, provision of α-casein, and nano delivery systems. Anthocyanins hinder cell migration, invasion, and proliferation by inducing apoptosis, suppressing cell cycle at G0/G1, S, or G2/M stages, and modulating signaling pathways such as apoptotic cascades, PI3K/Akt, MAPK, and NF-κB. Moreover, anthocyanins downregulate oncogenes (Bcl-2, MYC, and HER2) and improve the activity of tumor suppressor genes (TP53, BRCA1, and RB1). Anthocyanins, particularly cyanidin-3-O-glucoside, suppress inflammation and production of pro-inflammatory cytokines (COX-2, TNF-α, and IL-6) in colorectal cancer and hepatocellular carcinoma. Moreover, it causes cell cycle inhibition and mitochondrial dysfunction in ovarian and cervical malignancies. Although pre-clinical studies have proved anticancer activities, further clinical trials are required to validate its therapeutic impact and standard dose regimens.