Assessment of the relationship between miR-499C/T (rs3746444) polymorphism and lung carcinoma in Iranian population; a case-control study.

Introduction: Lung carcinoma is characterized by uncontrollable division of respiratory system cells with detrimental and lethal consequences on human health. Critical roles of microRNAs (miR) are scientifically approved in biological and pathological pathways, such as the role of miR-499 (rs3746444) in lung carcinomas. Thus, in this case-control investigation, we aimed to assess the probable relationship between miR-499C/T variant and the occurrence of lung carcinoma in Iranian population for the first time.

Methods: Genotype of miR-499 polymorphism was described by the Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) assay in patients and healthy individuals. Following definite diagnosis of lung carcinoma, the blood samples were collected, and the DNA extraction was performed by Salting-Out method. Finally, data were analysed by SPSS (v. 20) and the significant level was considered p-value<0.05.

Results: Statistically, the frequency of combined genotypes of CC+CT were 83.33% and 35% and TT+CT were 100% and 92% in case and control individuals, respectively. Also, individuals with genotypes of TC (OR: 3.08, CI95%: 3.03-3.17, p<0.0001), TC+CC (OR: 0.10, CI95%: 0.05-0.23, p<0.0001), CC (OR: 0, CI95%: 0.00-0.60, p=0.0214), and TC (OR: 0.07, CI95%: 0.030.15, p<0.0001) represented statistically significant (p<0.05) differences lung carcinoma than those with TT, TT, TT+TC, and TT+CC genotypes, respectively. The frequency of miR-499C (78.5%) and miR-499T (21.5%) alleles were also statistically significantly (p<0.05) difference associated with lung carcinoma in patients than controls.

Conclusion: In this study, a possible relationship among miR-499C/T polymorphism and lung carcinoma was detected in Iranian population. Since this study was conducted for the first time, thus other supplementary assessments are needed for definite conclusion.