STRESS OXY HÓA VỚI UNG THƯ

Abstract

Oxidative stress can be defi ned as an imbalance between free radicals or reactive oxygen species and antioxidants. The balance of reactive oxygen species generation and elimination is maintained by antioxidants. Antioxidants are molecules that signifi cantly delay or inhibit oxidation. The main causes
of oxidative stress are exogenous source such as diet, alcohol, stress, environmental pollution, smoke, radiation, medication and treatment, excessive of physical activity. Chronic oxidative stress aff ects to biological molecules, as oxidation of lipid, carbohydrate, enzymes, and damage of protein and DNA,
altered redox regulation, leading to infl ammation, a range of diseases and aging. Oxidative stress is closely related to all aspects of cancer, such as carcinogenesis, tumor-bearing state, treatment and prevention. Oxidative stress aff ects to carcinogenesis through two mechanisms, gene mutation that results from oxidized DNA, and gene extression change due to injured DNA binding to transcription factors. Some oxidative stress markers are considered as tumor markers, that are applied to diagnosis tumor-bearing state. Main mechanisms of anticancer drugs is creating apoptosis. Treatment with anticancer drugs creates oxidative stress, and active oxygen triggers apoptosis via p53 and cytochrome release from mitochondria. It is possible that excessive antioxidation mechnisms take part in anticancer drug resistance. Increasing antioxidants for protection against oxidative stress damage, inhibition of
nonspecifi c infl ammaton, and prevention of oxidative stresss are also useful in prevention of cancer.