LncRNA-DLEU1 and TRAF4 genes expression in patients with colorectal cancer, and effect of LncRNA-DLEU1 suppression on TRAF4 expression and cell proliferation

Abstract

Colorectal cancer is known as the third most common cancer and cause of cancer death in the world. The aim of this study was to investigate expression of DLEU1 and TRAF4 genes in colorectal cancer patients and effect of DLEU1 suppression on TRAF4 gene expression and cell proliferation. Materials and Methods: In the present study, 30 tumor tissues and adjacent non-tumor tissues were collected from colorectal cancer patients. After RNA extraction and cDNA synthesis from sample tissue, expression of TRAF4 and DLEU1 genes were measured by Real-Time PCR. Next, HT29 colorectal cancer cells were cultured and transfected with different concentrations of anti-DLEU1 siRNA by electroporation. Then, effect of transfection on expression of TRAF4 and DLEU1 genes as well as apoptotic genes was investigated. Finally, MTT and scratch assays was used to measure proliferation and migration of transfected cancer cells, respectively. Results: The expression of DLEU1 in colorectal cancer tissues significantly increased compared to adjacent non-cancerous tissues; while TRAF4 gene expression in colorectal cancer tissues significantly decreased compared to non-cancerous adjacent tissues. After transfection of anti- DLEU1 siRNA into cancer cells, expression of DLEU1 gene decreased significantly; While expression of TRAF4 gene increased significantly. Also, expression of pre-apoptotic genes increased significantly in transfected cancer cells; While expression of anti-apoptotic gene decreased significantly in transfected cancer cells. Investigation of cell survival and migration showed that suppressing expression of DLEU1 gene reduces survival and migration of colorectal cancer cells in a dose- and time-dependent manner.