Impaired activation of caspases and prevention of mitochondrial dysfunction in the metastatic colon carcinoma CC531s-m2 cell line.
In a previous paper we described the properties of a rapidly metastasizing cell line CC531s-m2 derived from the poorly metastasizing CC531s cell. The m2-cell line was relatively resistant to killing by NK cells. Both CD95L and TRAIL mediated apoptosis was decreased in the m2-cell line. Now, by flow cytometrical analysis of intra- and extra-cellular expressed receptors, we show that the localization of the receptors for CD95L and TRAIL was not altered in the CC531s-m2 cells as compared to the parental cell line. Subsequently caspase-activation and mitochondrial function were studied by enzymatic cleavage of fluorescent caspase-substrates and retention of the mitochondrial dye rhodamine-123, respectively. The activation of caspases as well as the loss of the mitochondrial membrane potential (MMP) was less in the CC531s-m2 cell line upon CD95L- and TRAIL-signalling. Furthermore, the sensitivity of the CC531-m2 towards cisplatin-induced apoptosis was strongly decreased. This was consistent with less mitochondrial damage, delayed caspase cleavage and decreased caspase activity. Altogether, we conclude that an Natural Killer-cell insensitive cell is less sensitive to CD95L- and TRAIL-induced apoptosis as well as anti-cancer drug induced apoptosis by prevention of mitochondrial damage and activation of caspases.
Velthuis
Jurjen H L
JH
Division of Toxicology, Leiden/Amsterdam Center for Drug Research, Leiden University, Gorlaeus Laboratrory, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Gavric
Zoran
Z
de Bont
Hans J G M
HJ
Nagelkerke
J Fred
JF
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D004789:Enzyme Activation / Q000187:drug effects; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology*; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D019014:fas Receptor / Q000032:analysis
D051017:Apoptosis Regulatory Proteins; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D053220:Receptors, TNF-Related Apoptosis-Inducing Ligand; D018124:Receptors, Tumor Necrosis Factor; D053221:TNF-Related Apoptosis-Inducing Ligand; C505640:Tnfrsf10b protein, mouse; C505654:Tnfsf10 protein, mouse; D014409:Tumor Necrosis Factor-alpha; D019014:fas Receptor; D020169:Caspases; D002945:Cisplatin