curcumin and lupeol

Accumulating data clearly indicate that induction of apoptosis is an important event for chemoprevention of cancer by naturally occurring dietary agents. In mammalian cells, apoptosis has been divided into two major pathways: the extrinsic pathway, activated by pro-apoptotic receptor signals at the cellular surface; and the intrinsic pathway, which involves the disruption of mitochondrial membrane integrity. This process is strictly controlled in response to integrity of pro-death signaling and plays critical roles in development, maintenance of homeostasis, and host defense in multicellular organisms. For chemoprevention studies, prostate cancer (PCa) represents an ideal disease due to its long latency, its high incidence, tumor marker availability, and identifiable preneoplastic lesions and risk groups. In this article, we highlight the studies of various apoptosis-inducing dietary compounds for prevention of PCa in vitro in cell culture, in preclinical studies in animals, and in human clinical trials.

Topics: Adenocarcinoma; Aged; Animals; Apoptosis; Carotenoids; Catechin; Clinical Trials as Topic; Curcumin; Drug Screening Assays, Antitumor; Flavonoids; Flavonols; Genistein; Humans; Lycopene; Lythraceae; Male; Mice; Mice, Nude; Mice, Transgenic; Middle Aged; Neoplasm Proteins; Pentacyclic Triterpenes; Phytotherapy; Plant Extracts; Prostatic Neoplasms; Resveratrol; Stilbenes; Tumor Cells, Cultured

It is estimated that nearly one-third of all cancer deaths in the United States could be prevented through appropriate dietary modification. Various dietary antioxidants have shown considerable promise as effective agents for cancer prevention by reducing oxidative stress which has been implicated in the development of many diseases, including cancer. Therefore, for reducing the incidence of cancer, modifications in dietary habits, especially by increasing consumption of fruits and vegetables rich in antioxidants, are increasingly advocated. Accumulating research evidence suggests that many dietary factors may be used alone or in combination with traditional chemotherapeutic agents to prevent the occurrence of cancer, their metastatic spread, or even to treat cancer. The reduced cancer risk and lack of toxicity associated with high intake of fruits and vegetables suggest that specific concentrations of antioxidant agents from these dietary sources may produce cancer chemopreventive effects without causing significant levels of toxicity. This review presents an extensive analysis of the key findings from studies on the effects of dietary antioxidants such as tea polyphenols, curcumin, genistein, resveratrol, lycopene, pomegranate, and lupeol against cancers of the skin, prostate, breast, lung, and liver. This research is also leading to the identification of novel cancer drug targets.

Topics: Animals; Anticarcinogenic Agents; Antioxidants; Carotenoids; Curcumin; Dietary Supplements; Fruit; Genistein; Humans; Lycopene; Neoplasms; Oxidative Stress; Pentacyclic Triterpenes; Resveratrol; Stilbenes; Triterpenes