Sir,
The article “Naturally occurring products in cancer therapy” in the dental science section of the journal was read with interest.[1] Though lycopene was mentioned in the article, its role and mechanism of action against cancer was missing. This article aims to fill this void.
Lycopene is a red carotenoid found in ripe tomatoes, grapefruits, and red watermelon with anti-oxidant, anti-inflammatory, and chemopreventive properties against cancer.[2,3,4,5] Its absorption into the human body is more efficient when consumed from heated and lipid-rich dietary sources than raw sources.[4] It is observed to accumulate in the prostate and has anti-proliferative and pro-apoptotic activities against prostate cancer.[6]
Lycopene quenches singlet oxygen, scavenges free radicals, and prevents the oxidative damage of DNA. Thus, it prevents potential transformation of normal cells to cancer cells.[4,5] It also modulates gene functions, carcinogen-metabolizing enzymes, apoptosis, and immune function.[4,5] It increases gap junction communications, anti-proliferation, pro-differentiation, and anti-lipid peroxidation activities.[4] Lycopene induces cytochrome P450 and hepatic quinine reductase which helps in the expulsion of carcinogens and foreign substances from the body. It inhibits phosphorylation of anti-oncogenes such as p53 and Rb.[4] It also inhibits G0/G1 and S-phase of the cell cycle.[5,6] Lycopene is observed to inhibit the activities of platelet-derived growth factor-BB, matrix metalloprotienases-2 (MMP-2), and MMP-9 resulting in decreased tumor growth, invasion, and metastasis.[5] It also regulates dysplastic changes and is of benefit in patients with oral premalignant lesions such as leukoplakia and initial stage of oral submucous fibrosis (OSMF).[2,3,7] In OSMF patients, lycopene increases mouth opening, decreases burning sensation of mouth, and inhibits abnormal fibroblasts and inflammation.[4] Lycopene is observed to inhibit fibrogenesis of hepatic tissues in LEC rats.[3] Lycopene is safe and has no adverse effects within a dietary dose of 3 g/kg/day.[8] Thus, lycopene with its anti-oxidant and multi-targeted anti-carcinogenic properties is of promising use in preventing and combating cancer.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
References
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