Resistance against tumour necrosis factor α apoptosis by the cellular prion protein is cell‐specific for oral, colon and kidney cancer cell lines

Since the discovery of PrP^C (cellular prion protein), most studies have focused on its role in neurodegenerative diseases, whereas its function outside the nervous system remains obscure. We investigated the ability of PrP^C in resisting TNFα (tumour necrosis factor α) apoptosis in three PrP^C‐transiently transfected cancer cell lines, renal adenocarcinoma ACHN, oral squamous cell carcinoma HSC‐2 and colon adenocarcinoma LS174T. PrP^C‐expressing ACHN and LS174T cells had higher viabilities compared with the mock‐transfected cells, while the transient overexpression of PrP^C had minimal overall effect on HSC‐2 cells due to its high endogenous PrP^C expression. Cell cycles were also analysed, with both PrP^C expressing ACHN and LS174T cells having a significantly higher proliferative index than mock‐transfected cells. Flow cytometry analysis indicated a G₁/S‐phase cell cycle transition in both PrP^C‐expressing ACHN and LS174T cells. PrP^C resists TNFα apoptosis due to a modest, but statistically significant, cell‐specific cytoprotection compared with mock‐transfected cells.