Sulofenur cytotoxicity and changes in cytosolic calcium and mitochondrial membrane potential in human colon adenocarcinoma cell lines

Abstract Sulofenur treatment (12.5 μM-1 mM) of colon adenocarcinoma cell lines resulted in dose- and time-dependent cell killing. LYc 5 cells were viable longer than GC 3 c 1 , cells. Each concentration resulted in elevation of cytosolic calcium [Ca 2+ ] i ) for both cell lines. At lower doses, elevation was delayed for LYc 5 cells. GC 3 C 1 cells after 1 mM treatment in Ca 2+ -free HBSS showed no rise of [Ca 2+ ] i . GC 3 C 1 cells after carbonyl cyanide- m -chlorophenylhydrazone rapidly lost rhodamine 123 fluorescence from mitochondria; after 1 mM sulofenur, fluorescence faded slowly. Following treatment, cells became rounded, blebs formed and the cells died. Results suggest that elevated [Ca 2+ ] i plays an important role in sulofenur cytotoxicity.