The Effect of Radiation on the Expression Level of DANCR and TUG۱ LncRNAs in Breast Cancer Cell Lines

Introduction: Radiotherapy is a standard and effective modality for breast cancer treatment, through induction of DNA damages notably DNA double-strand breaks which are involved in radiation-induced cell death. All radiation-induced DNA damages are subjected to various repair processes, therefore, interference in the DNA repair pathways might result in radio-resistance. Non-coding RNAs are a diverse group of functional RNA molecules that are not translated into proteins. Recent studies have shown that radiation can cause expression changes in noncoding RNAs.Materials and Methods: MCF-۷ and MDA-MB-۲۳۱ cell lines were grown in a DMEM culture medium supplemented with fetal bovine serum and antibiotics. At exponential growth, cells were exposed to various doses of megavoltage X-rays. ۲۴ and ۴۸ h after irradiation cells were harvested, RNA was extracted and cDNA was synthesized. The expression level of lncRNAs was measured using quantitative real-time PCR.Results: This study showed that radiation could increase DANCR and TUG۱ lncRNAs expression in breast cancer cell lines ۲۴ and ۴۸ h after receiving radiation. Also, the results suggested that after radiation, the expression of DANCR in the radioresistant cell line was higher than the radiosensitive one; in the case of TUG۱, it’s unlike DANCR.Conclusions: The radiation increased the expression of DANCR and TUG۱ lncRNAs in breast cancer cell lines because the expression of DANCR in the MDA-MB- ۲۳۱ was higher than in the MCF-۷. In contrast, the expression level of TUG۱ in MCF-۷ was higher than the MDA-MB-۲۳۱. Therefore, lncRNAs, DNACR, and TUG۱ might play a role in the radioresistance and radiosensitivity of breast cancer, respectively.

کلیدواژه ها:

DNA Repair ، DANCR ، TUG۱ ، breast cancer ، Radiosensitivity ، Radioresistance