RNA-Interference-Mediated Silencing of OCT4B1, Alters Expression Profile of Several TNF Ligand/ Receptor Transcripts in Human Tumor Cell Lines

Background: The OCT4B1 as a new discovered variant of OCT4 is expressed in both cancer cell and tissues. This variant with its anti-apoptotic properties aid cancer cells to scape from apoptosis. TNF ligands and receptors are amongst two categories of eleven gene families involved in the apoptosis pathway. Therefore, the aim of the present study was to investigate the effects of OCT4B1 suppression on several transcripts of both TNF ligands and receptors family in some tumor cell lines. Methods: The AGS (gastric adenocarcinoma), 5637 (bladder tumor) and U-87MG (brain tumor) tumor cell lines were transfected with specific OCT4B1 siRNA and , as well as a scrambled sequence and PBS, as controls, using Lipofectamine 2000 comerical kit. The expression of TNF ligand and receptor transcripts were evaluated in parallel with beta-actin (as housekeeping gene) using Real-Time PCR technique. Results: our results indicated that in TNF ligand transcripts family, the mRNA level of TNF transcripts was up-regulated and inversely TNFSF8, TNFSF7, TNFSF10, TNFSF1 and TNFSF6 was down-regulated. We observed also that in TNF receptor transcripts family, six transcripts including, TNFRSF 10A, TNFRSF10B, TNFRSF11B, TNFRSF1A, TNFRSF21 and TNFRSF25 were up-regulated, while TNFRSF9 and CD27 were down-regulated. Conclusions: According to these results, it may be concluded that OCT4B1 suppression can lead to apoptosis in tumor cell lines via up-regulation of several TNF ligand and receptor transcripts. Thus, OCT4B1 suppression effects on TNF and its receptors may be considered as promising target genes in future studies in cancr research and therapy.