Drug resistance associated with loss of p53 involves extensive alterations in microtubule composition and dynamics.
In the present study, we compared the dynamics and composition of microtubules in cell lines derived from the human breast adenocarcinoma MCF-7 containing either the wild-type p53 (wt-p53; MN1) or a dominant-negative variant of p53 gene (mut-p53; MDD2). Mut-p53 cells were significantly resistant to the cytotoxicity of the microtubule-targeted drugs (vinca alkaloids and taxanes), as compared with wt-p53 cells. Studies by high-resolution time-lapse fluorescence microscopy in living cells indicated that the dynamics of microtubules of mut-p53 cells were altered in complex ways and were significantly increased as compared with microtubules in wt-p53 cells. The percentage of time microtubules spent in growing and shortening phases increased significantly, their catastrophe frequency increased, and their overall dynamicity increased by 33%. In contrast, their shortening rate and the mean length shortened decreased. Cells containing mut-p53 displayed increased polymerisation of tubulin, increased protein levels of the class IV beta-tubulin isotype, STOP and survivin, and reduced protein levels of class II beta-tubulin isotype, MAP4 and FHIT. We conclude that p53 protein may contribute to the regulation of microtubule composition and function, and that alterations in p53 function may generate complex microtubule-associated mechanisms of resistance to tubulin-binding agents.
Galmarini
C M
CM
INSERM 590-Laboratoire de Cytologie Analytique, Faculté de Médécine Rockefeller, Lyon 69373, France. fgalma@rockefeller.univ-lyon1.fr
Kamath
K
K
Vanier-Viornery
A
A
Hervieu
V
V
Peiller
E
E
Falette
N
N
Puisieux
A
A
Ann Jordan
M
M
Dumontet
C
C
D017766:Acid Anhydride Hydrolases; D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D000951:Antigens, Neoplasm / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D002417:Cattle; D017931:DNA Primers / Q000737:chemistry; D019008:Drug Resistance, Neoplasm; D016147:Genes, Tumor Suppressor; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008156:Luciferases / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008870:Microtubules / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D009363:Neoplasm Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D014162:Transfection; D014404:Tubulin / Q000378:metabolism; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism*; D000099170:Bis(5'-adenosyl)triphosphatase
D017766:Acid Anhydride Hydrolases; D000951:Antigens, Neoplasm; D000970:Antineoplastic Agents; D017931:DNA Primers; D051034:Inhibitor of Apoptosis Proteins; D008156:Luciferases; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D009419:Nerve Tissue Proteins; D000077022:Survivin; D014404:Tubulin; D016159:Tumor Suppressor Protein p53; D000099170:Bis(5'-adenosyl)triphosphatase; C107489:BIRC5 protein, human; C491894:MAP6 protein, human