HN protein of Newcastle disease virus sensitizes HeLa cells to TNF-α-induced apoptosis by downregulating NF-κB expression

HN protein of Newcastle disease virus sensitizes HeLa cells to TNF-α-induced apoptosis by downregulating NF-κB expression

Archives of Virology, June 2016

27294845

R. S. Rajmani, Shishir Kumar Gupta, Prafull Kumar Singh, Ravi Kumar Gandham, A. P. Sahoo, Uttara Chaturvedi, Ashok K. Tiwari

Hemagglutinin neuraminidase (HN) is a membrane protein of Newcastle disease virus (NDV) with the ability to induce apoptosis in many transformed cell lines. TNF-α is a multi-factorial protein that regulates cell survival, differentiation and apoptosis. In a previous study, we reported that HN protein induces apoptosis by downregulating NF-κB expression. Further, we speculated that downregulation of NF-κB expression might sensitize HeLa cells to TNF-α-mediated apoptosis. Therefore, the present study was undertaken to investigate if HN protein could sensitize HeLa cells to TNF-α and to examine the apoptotic potential of the HN protein and TNF-α in combination. The results revealed that the pro-apoptotic effects were more pronounced with the combination of HN and TNF-α than with HN or TNF-α alone, which indicates that the HN protein indeed sensitized the HeLa cells to TNF-α-induced cell death. The results of the study provide a mechanistic insight into the apoptotic action of HN protein along with TNF-α, which could be valuable in treating tumor types that are naturally resistant to TNF-α.