Protein expression profiles of necrosis and apoptosis induced by 5-fluoro-2'-deoxyuridine in mouse cancer cells.
We have investigated the molecular mechanisms regulating the necrosis and apoptosis that occur on treatment of mouse mammary tumor FM3A cells with 5-fluoro-2'-deoxyuridine (FUdR), a potent anticancer agent, using the original clone F28-7 and its variant F28-7-A cells. Previously, we reported an interesting observation that FUdR induces a necrotic morphology in F28-7 but an apoptotic morphology in F28-7-A cells. We have now analyzed the protein expression profiles of these FUdR-induced necrosis and apoptosis. Thus, proteome analysis of these clones by two-dimensional gel electrophoresis and mass spectrometry showed that the cytoplasmic intermediate filament protein, cytokeratin-19, is expressed at a significantly higher level in F28-7 than in F28-7-A cells. This strong expression was detected both in untreated and FUdR-treated stages of F28-7 cells. We interpreted this phenomenon as suggesting that cytokeratin-19 possesses a function in leading the cell to apoptosis. We performed a knockdown of cytokeratin-19 expression in F28-7 cells by use of the small interfering RNA technique. Indeed, a lowering of the cytokeratin-19 expression down to the level in F28-7-A occurred, and the FUdR-induced death morphology of this knockdown F28-7 was apoptosis, instead of the necrosis usually observable in the FUdR-treated F28-7. It is known that the cytoskeletal protein cytokeratin-19 undergoes caspase-mediated degradation during apoptosis. Our present finding provides an interesting possibility that cytokeratin-19 may have a key role in regulating cell-death morphology.
Sato
Akira
A
Faculty of Pharmaceutical Sciences, Okayama University, Tsushima, Okayama 700-8530, Japan.
Satake
Akito
A
Hiramoto
Akiko
A
Wataya
Yusuke
Y
Kim
Hye-Sook
HS
D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D045744:Cell Line, Tumor; D048429:Cell Size / Q000187:drug effects; D015180:Electrophoresis, Gel, Two-Dimensional; D005467:Floxuridine / Q000378:metabolism / Q000494:pharmacology*; D020869:Gene Expression Profiling; D053539:Keratin-19 / Q000235:genetics / Q000378:metabolism; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008969:Molecular Sequence Data; D009336:Necrosis; D020543:Proteome / Q000187:drug effects*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism
D053539:Keratin-19; D020543:Proteome; D034741:RNA, Small Interfering; D005467:Floxuridine