PDRG1, also known as C20orf126, belongs to the prefoldin subunit beta family. It is predominantly expressed in normal testis and exhibits reduced but detectable expression in other organs. PDRG1 may play a role in chaperone-mediated protein folding. PDRG1 is overexpressed in tumors relative to normal tissues. Its expression is upregulated in multiple malignancies including cancers of the colon, rectum, ovary, lung, stomach, breast and uterus when compared to their respective matched normal tissues. Thus PDRG1 is a high-value novel tumor marker that could play a role in cancer development and/or progression.