Investigation of RASSF4 gene in head and neck cancer patients

Head and neck cancers are classified as group cancers that initiates in tissues of oral cavity, nose, pharynx, larynx and salivary glands. RAS is a protein that shows intrinsic GTP binding and GTPase. It has the ability to activate the pathways controlling acceleration and inhibiton of growth. RASSF gene family can inhibit the growth of RAS oncogene. The family consists of 10 proteins that act as a tumour supressor and inactivated by the hypermethilation of promotor area in tumour subgroups. It is estimated that this gene family has a role in cell cycle control, apoptosis, cell migration and mitosis control. A decrease in the gene expression was reported when apoptosis and cell cycle comes to a halt along with the occurence of cancer. This study evaluated RASSF4 gene expression levels in healthy and diseased tissues dissected from the patients (n=69) diagnosed with head neck cancer. No statistical difference was observed (P>0,05). DNA samples taken from 69 diseased and 70 healthy subjects was evaluated to determine areas of RS7896801 and RS884879 gene variants. Results for RS7896801 revealed a x2.4 increase of G-allel presence in diseased group (p=0,015). For control, the increase in presence of AA genotype was statistically significant (p=0,015). Distribution of genotype and allels for RS884879 showed an increase of x2,2 in CC genotype for healthy group (p=0,048) whereas in diseased group, the presence of T allel showed a significant increase (p=0,048). Serum levels of diseased (n=69) and control (n=70) group was tested by using ELISA technique. No statistically significant differences was observed between the study groups (p>0,05). Our study reveals the first data about the RASSF4 gene expression levels, serum levels and areas of RS7896801 and RS884879 gene variants in head and neck cancers. We believe that this study will play a pioneering role for the next studies on RASSF4 gene.