The Relationship between the Expression of Small Heat-Shock Proteins and Suppression of OCT4B1

OCT4B1, a variant of OCT4, is expressed in both cancer cells and tissues. This variant has a main role in the regulation of both apoptotic and stress (heat-shock proteins) pathways. The aim of this study was to investigate the effects of OCT4B1 silencing on the expression of small heat-shock proteins (sHSPs)in three human tumor cell lines.
AGS (gastric adenocarcinoma), 5637 (bladder tumor) and U-87MG (brain tumor) cell lines were transfected with specific OCT4B1 siRNA (test group) and scramble siRNA (control group), using siRNA and Lipofectamine. Real-Time PCR Array technique was applied and the fold changes were calculated using RT2 Profiler PCR Array Data Analysis version 3.5.
It was revealed that HSPB1, HSPB6 and HSPE1 were down-regulated in all three studied tumor cell lines and HSPB2, HSPB7 and HSPB8 were down-regulated in two of three studied tumor cell lines (AGS and 5637). It was also revealed that HSPB3 was down-regulated in 5637 cell line and up-regulated in AGS and U87MG cell lines.
According to the results, it may be concluded that there is a direct relationship between OCT4B1 and sHSPs gene family expression. Thus, suppression of OCT4B1 may be considered in cancer therapy/research.