A potential novel marker for human prostate cancer:: voltage-gated sodium channel expression in vivo

Functional expression of voltage-gated sodium channel alpha-subunits (VGSC alpha s), specifically Na(v)1.7, is associated with strong metastatic potential in prostate cancer (CaP) in vitro. Furthermore, VGSC activity in vitro directly potentiates processes integral to metastasis. To investigate VGSC alpha expression in CaP in vivo, immunohistochemistry and real-time PCR were performed on human prostate biopsies (n>20). VGSC alpha immunostaining was evident in prostatic tissues and markedly stronger in CaP vs non-CaP patients. Importantly, RT-PCRs identified Na(v)1.7 as the VGSC alpha most strikingly upregulated (similar to 20-fold) in CaP, and the resultant receiver-operating characteristics curve demonstrated high diagnostic efficacy for the disease. It is concluded that VGSC alpha expression increases significantly in CaP in vivo and that Na(v)1.7 is a potential functional diagnostic marker.