TNF and cholangiocarcinoma: Interestingly, the addition of zVAD-fmk completely inhibited TNF-α and Smac mimetic-induced cell death in cell lines lacking RIPK3 expression, including MMNK-1, KKU100, and KKU214 cells, while CCA cell lines expressing RIPK3, including KKU213, RMCCA-1, and HuCCT-1 cells, were still sensitive to TNF-α/Smac mimetic/zVAD-fmk (TSZ)-induced cell death.