Interferon-alpha inhibits proliferation and induces apoptosis of merkel cell carcinoma in vitro

Abstract

Merkel cell carcinoma is a tumor with aggressive biological behavior and limited response to chemotherapy. The present study investigated the effect of interferon (IFN)-alpha on growth and apoptosis of Merkel carcinoma cells in vitro. Proliferation of MCC-1 cell line was reduced dose-dependently by IFN-alpha and diminished when higher IFN-alpha concentrations were used. Additionally, IFN-alpha potently decreased DNA-synthesis and Ki67/MIB-1 proliferation index of MCC-1 cultures. Furthermore, IFN-alpha induced dose-dependently apoptosis of MCC-1 cells as shown by caspase-3 activation, and detection of apoptotic DNA strand breaks and fragmented nuclei. These findings suggest that IFN-alpha may have antitumor activity against Merkel cell carcinoma.