Objective: 

Voltage-gated sodium channels (VGSCs) are present in excitable cells, where they are responsible for the upstroke of the action potentials. Interestingly, presence of VGSCs in non-excitable cells including metastatic cancer cells has been demonstrated using electrophysiological and molecular methods. Although the physiological basis of cancer is not known it is beginning to emerge that expression of VGSC contributes to the metastatic progression of various types of cancer, such as prostate, breast and lung. The purpose of this study was to evaluate the expression of VGSC protein in Mat-LyLu tumour, an established rat model developed to study prostate cancer (PCa) progression.

Methods: 

PCa model was induced in male Copenhagen rats by subcutaneous implantation of strongly metastatic Mat-LyLu rat PCa cell. Subcutaneous implantation of Mat-LyLu cells resulted in the development of lung metastases. The primary tumours and the corresponding lung metastases were then examined by immunohistochemistry using anti-sodium channel (III-IV linker region) antibody.

Results: 

Expression of VGSCs protein was confirmed by immunocytochemistry in cultured Mat-LyLu cells, which was consistent with the patch-clamp experiments in literature. In immunohistochemical studies, all tumour samples showed a positive VGSC expression. The same VGSC protein expression pattern between primary tumour and related metastasis was observed. No expression of VGSCs was detected in negative controls without the antibody.

Conclusions: 

Our results suggest that the Mat-LyLu tumour is a reliable model system for evaluating the role of VGSCs in PCa pathobiology/physiology. Further studies regarding the modulation of VGSCs activity in this model will provide valuable information with regard to the role of these channels in the development and metastatic progression of PCa.