Down-Expression of miRNA-98 and Over-Expression of miRNA-9 Can Result in Inadequate Immune System Response against Lung Cancer

Abstract

Lung cancer is a disease presenting high incidence and mortality rates. Its most common type is non-small cell lung cancer (NSCLC), constituting about 80-85% of all cases. MicroRNAs (miRNAs) are the molecules playing a role in the regulation of genes. Two crucial cytokines in cancer are interleukin (IL)-10 and IFN-γ. Our objective was to investigate the expression of miRNA-9, miRNA-98, JAK, and STAT3 in patients with NSCLC and detect the cytokine level of IL-10. A total of 50 patients with NSCLC participated in this study. Besides, 50 healthy blood samples were selected as the control group. Real-time PCR determined the expression levels of miRNAs so that the RNAs extracted from the patients' peripheral mononuclear cells (PBMC) were initially synthesized, and cDNA was then extracted. Finally, the synthesized cDNA was amplified using real-time PCR, and its expression was compared to the control group. ELISA technique was used to detect IL-10 in plasma. Our result showed a low level of expression of miRNA-98, JAK, and STAT3 and a high-level expression of miRNA-9. ELISA test indicated a high cytokine level of IL-10 in the NSCLC patients' serum compared to the healthy controls.