Aim of study: WEE1, a member of serine/threonine protein kinase family is the master inhibitor of cyclin-dependent kinase 1 in cell cycle. Over-expression of WEE1 in glioblastomas (GBMs) and some other cancers has been shown. Here, we investigated the expression of WEE1 in 13 brain samples from GBM patients and two GBM cell lines. Further to that, we asked whether if knocking down WEE1 expression in the cell lines change tumor cells' reaction.
Materials and methods: All brain tumor samples were collected after confirmed pathological diagnosis. Western blotting was used to screen the expression of WEE1 and a panel of tumor markers. As a model of WEE1 gene silencing with small hairpin RNA (shRNA) technology in GBMs, A172, and U373GM cell lines were transfected with four WEE1 specific shRNAs. The growth characteristics of the cells and the expression of a panel of downstream genes were investigated after gene suppression.
Results: All GBMs and both cell lines over-expressed WEE1. Transduction of the cell lines with different shRNAs suppressed WEE1 expression with different extent and pooling of four shRNAs together resulted in additive effect. Suppression of WEE1 not only repressed cellular growth but also changed the profile of gene expression of the cells. Quantitative real-time polymerase chain reaction showed also reduced expression of genes such as hypoxia-inducible factor-1, B-cell lymphoma-2, vascular endothelial growth factor, and p53 with crucial roles in tumor survival and invasiveness.
Conclusion: These results highlight the key role of WEE1 suppression to combat GBMs. Moreover, it showed beneficial possibilities of WEE1 suppression with different anticancer approaches for neurological malignancies.