QPRT and cancer: One of these enzymes, namely QPRT, is highly upregulated in various cancers, including breast, thyroid, colon, ovarian, cervical carcinomas, melanomas, gliomas and lymphomas and its expression is linked to chemoresistance, elevated NAD+ production, the activation of purinergic receptors, phosphorylation of the myosin light chain, leading to elongated cell morphology and metastatic features, such as migration and invasion.13