Fig. 1

TPL induces pyroptosis in head and neck cancer cells. a Cell viability assays. HK1, FaDu and C666–1 cells were exposed to various concentrations of TPL (0, 5, 25, 50 and 150 nM) for 24 h or 48 h. Cell viability were determined by MTT assays. b Colony formation assays. Cells were treated with various doses of TPL (0, 1, 2, and 5 nM) for 48 h and then allowed to grow for 2 weeks in fresh culture medium. Colonies were visualized by crystal purple staining. Values are mean ± SD from triplicate experiments. c Apoptotic cell frequencies treated without or with TPL (50 nM) for 24 h were determined by annexin V/PI assays. d Morphological alterations induced by TPL (50 nM) treatment. Arrow showed cell swelling and rupture. e IL-1β released into culture medium was detected by ELISA assays. f LDH1 activity assays. LDH1 activity in culture mediums of cells treated without or with TPL (50 nM) for 24 h were measured by LDH1 kit. g Release of LDHA proteins to culture mediums were detected by western blot assays. *P < 0.05, **P < 0.01, ***P < 0.001