Cholesterol content can vary distinctly between normal and
cancer cells, with elevated levels in
cancer cells. Here, we investigated
cholesterol sequestration with methyl-β-
cyclodextrin (MCD), and pore-formation with the
ostreolysin A/pleurotolysin B (OlyA/PlyB)
protein complex that binds to
cholesterol/
sphingomyelin-rich membrane domains. We evaluated the effects on viability of T24 invasive and RT4 noninvasive human urothelial
cancer cells and normal porcine urothelial (NPU) cells.
Cholesterol content strongly correlated with cancerous transformation, as highest in the T24 high-grade invasive urothelial
cancer cells, and lowest in NPU cells. MCD treatment induced prominent cell death of T24 cells, whereas OlyA/PlyB treatment resulted in greatly decreased viability of the RT4 low-grade noninvasive
carcinoma cells. Biochemical and transmission electron microscopy analyses revealed that MCD and OlyA/PlyB induce necrotic cell death in these
cancer cells, while viability of NPU cells was not significantly affected by either treatment. We conclude that MCD is more toxic for T24 high-grade invasive urothelial
cancer cells, and OlyA/PlyB for RT4 low-grade noninvasive urothelial
cancer cells, and neither is toxic for NPU cells. The
cholesterol and
cholesterol/
sphingomyelin-rich membrane domains in urothelial
cancer cells thus constitute a selective therapeutic target for elimination of urothelial
cancer cells.