Phytochemistry, Bioavailability, and Molecular Mechanisms Underlying Multitarget Anticancer Activity of Aloe vera

Background/Objectives: Cancer, a multifactorial disease with uncontrolled cell growth, oxidative stress, inflammation, genomic instability, and molecular signaling pathways, is a global health concern, leading to the ~20 million newly diagnosed cases annually. Although conventional therapy has been shown to enhance the survival rates of cancer patients, its clinical efficacy is limited by certain side effects that occur as a result of treatment, thus necessitating the exploration of plant-derived bioactive compounds for their potential as safer and alternative supportive therapeutic agents. Aloe vera, known as the plant of immortality, comprises phytochemicals, such as anthraquinones (aloe-emodin, emodin, and aloin), polysaccharides (acemannan), flavonoids, and phenolic acids, which contribute to the pharmacological effect of the compound. Methods: This review summarizes the anticancer potential of Aloe vera, and the data were retrieved from databases, such as PubMed, Google Scholar, ScienceDirect, Web of Science, and Wiley Online Library, during the time period of 2015 to 2025. Results: The literature revealed that Aloe vera and its bioactive compounds have dose-dependent cytotoxic and anti-proliferative properties against hepatocellular, cervical, colorectal, lung, breast, prostate, and hematological cancers, which are significantly mediated by apoptosis and pyroptosis induction, reactive oxygen species (ROS) production, mitochondrial dysfunction, inhibition of angiogenesis and metastasis, and the modulation of key signaling pathways, particularly PI3K/Akt, MAPK, NF-кB, p53, and Wnt/β-catenin. Furthermore, anthraquinones, including Aloe-emodin, demonstrate potent anticancer effects at micro-molar doses, and polysaccharides increase immune reactions and provide tumor immunity. Conclusions: Conclusively, Aloe vera is a promising multi-target natural compound, particularly efficient in the treatment of cancer. However, despite significant therapeutic potential, more research on pharmacokinetics, standard dose, and controlled clinical trials of Aloe vera is required to validate clinical applicability.