The role of GADD45A in resistance to oxidative stress-mediated cell death in human colon tumor cell lines

ABSTRACT

Objective: GADD45A is a growth arrest-associated gene, directly involved in the maintenance of genomic stability. In fact, in the absence of this protein cells became sensitized to death by ultraviolet irradiation or cisplatin. However, this role with respect to cell damage triggered by Reactive Oxygen Species (ROS) is not well understood. Thus, in an attempt to evaluate its role in oxidative stress-induced apoptosis, we analyzed its expression after induction of ROS in human colon cell lines. Material and methods: Cell lines derived from human colon tumors (RKO-AS45-1 and HuTu-80) were treated with Menadione (MEN) and Hydrogen Peroxide (HP). Next, the expression of GADD45A was evaluated by semi-quantitative RT-PCR analysis. Results: The results indicated that expression of this gene was associated with resistance to apoptosis. Additionally, cells with high expression of GADD45A were resistant to treatment with oxidative stress-inducing compounds. Conclusion: In conclusion, we propose that the expression of the GADD45A gene can be used as a functional tool to predict cellular responses to antitumor treatments.