Zahra Jomehzadeh - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
Farhang Haddad - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran
Maryam.M Matin - Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran- Novel Diagnostics and Therapeutics Research Group, Institute of Biotechnology, Ferdowsi University of Mashhad, Iran
Shokouhozaman Soleymanifard - Department of Medical Physics, Mashhad University of Medical Sciences, Mashhad, Iran

There are several studies suggesting the role of aneuploidy in tumor formation. Aneuploid cells aredifferent from normal ones in term of gene expression and proteome. Cells with different amount and kind ofproteins might act differently to external stimuli, including ionizing irradiation. Currently, radiotherapy is one ofthe main methods in fight against cancer, therefore, it is important to understand the response of the aneuploidytumorcells to irradiation. To investigate the chromosomal effect of gamma irradiation on aneuploid cells, L929cells were treated with 1.5 ng.ml-1 of vinblastine to induce aneuploidy. Vinblastine-treated cells were left to recoverfor 72 h and irradiated with 1 Gy of gamma radiation. Induced chromosomal damages were investigated usingmicronucleus (Mn) assay. Data showed that vinblastine and gamma irradiation both were able to significantlyincrease micronucleated-binucleated cells (MnBi) frequency. However, 1 Gy gamma irradiation of the cells after 72h of vinblastine treatment led to the lower frequency of MnBi compared to irradiated cells. Results of this studysuggest that vinblastine treatment of cells before irradiation not only did not sensitize the cells to radiation-inducedchromosomal abnormalities, but also had radio-protective effect for these cells. This result could be useful inplanning cancer therapy regimes.

Gamma, Vinblastine, L929 cells, Micronucleus assay, Binucleated cells