Abstract
The miRNAs nuclear export protein XPO5 has been previously studied in several individual malignancies. In our recent study we have demonstrated that excess levels of XPO5 enhanced the proliferation of prostate cancer cells. Similarly, there are studies to support the inhibitory role of XPO5 in cancers. In order to evaluate discrepancies in the expression levels of XPO5 in differential tumor types, we quantified the expression of XPO5 using gene expression RNA-seq data for several tumor types which were independently confirmed by immunohistochemistry in multiple organs cancer tissue microarray (TMAs) experiment. We found that while some tumors (Breast, Bladder, Lymph-node, Lung, Esophagus and Ovary) showed higher differences between normal and malignant tumors in XPO5 expression, there were tissues (Kidney and Brain) that have a significantly lower XPO5 expression in malignant tumors. We further studies these observations of overexpression and down-regulation of XPO5 in breast and kidney cancer cell lines and found that XPO5 might have a dual role in promoting or inhibiting tumor growth in different cancer tissue types.