Marjan Salehi,1,*
1. Department of microbiology, Islamic Azad University of Qom, Iran
Introduction: cancer is a leading cause of death worldwide, and this problem is increasing sharply. Much of this increase is due to aging worldwide populations, smoking, obesity, diabetes, alcohol intake, and genetic factors. Although different treatments are applied for curing cancer such as surgery, targeted therapies, radiotherapy, immunotherapy, and chemotherapy, some types of cancer cells are resistant and in some cases, these methods lead to dangerous side effects. Therefore, scientists are looking to use natural substances that directly fight cancer cells.
Polyphenols are a large group of herbal compounds that are known for their structural features consist of a three-membered flavan ring and multiple phenol units. These compounds are found in fruits, green tea, coffee, wine, and cocoa. These organic agents are classified into several subclasses including catechins, flavonoids, catechins, isoflavones, curcuminoids, chalcones, and phenolic acids.
Methods: some studies represented that what makes these agents greatly beneficial is that they attack cancer cells directly. Free radicals that exist in our cells are the causes of oxidative stress. Oxidative stress is involved in various pathological states including cancer. Polyphenols have antioxidant effects and they are a severe barrier against the generation of free radicals. This property stabilizes free radicals and prevents them from damaging the cellular components. Moreover, polyphenols are able to induce cell death by altering the expression of apoptosis-related genes. Some studies showed that curcumin diminishes phosphorylation activation of the mitogen-activated protein kinase (MAPK) signaling pathway and increases PI3K/Akt protein expression. In addition, EGCG significantly increases the activity of caspase-3 and -7 as well as apoptotic cells.
Results: By studying several different tests on the effects of polyphenols on the cancer process, we concluded that the repeated use of these compounds with a certain dose can reduce the growth and proliferation of cancer cells and also prevent metastasis, in cases where the drug is used simultaneously. Polyphenolic compounds were used in chemotherapy, and the negative side effects of these drugs were reduced
Conclusion: In light of this review, Although there is little information about the effects of natural compounds in vivo, the absence of systemic side effects developed by polyphenols, and their epigenetic involvement in cancer biology, make them particularly interesting. Finally, the aim of this paper is a short review of the use of polyphenols to fight cancer cells from different pathways.