title: Proliferation of cancer cells despite CDK2 inhibition.
abstract: We have investigated the contribution of CDK4 and CDK2 inhibition to G1 arrest in colon cancers following inhibition of the MEK/MAP kinase pathway. CDK4 inhibition is sufficient to cause arrest, but inhibition of CDK2 by p27 Kip1 redistribution or ectopic expression has no effect on proliferation. Likewise, inhibition of CDK2 through expression of dominant-negative (DN) CDK2 or antisense oligonucleotides did not prevent cell proliferation in these cells. We therefore tested whether CDK2 activity is dispensable in other cells. Surprisingly, osteosarcomas and Rb-negative cervical cancers continued to proliferate after depletion of CDK2 through antisense oligonucleotides or small interfering (si) RNA. Here we report of sustained cell proliferation in the absence of CDK2, and we suggest that CDK2 is not a suitable target for cancer therapy.
authors.affiliation: Cancer Research Institute and Comprehensive Cancer Center, University of California, San Francisco, CA 94143, USA.
authors.forename: Osamu
authors.initials: O
authors.lastname: Tetsu
authors.forename: Frank
authors.initials: F
authors.lastname: McCormick
mesh_terms: D001549:Benzamides / Q000494:pharmacology; D002070:Butadienes / Q000494:pharmacology; D042846:CDC2-CDC28 Kinases; D002455:Cell Division; D003110:Colonic Neoplasms / Q000378:metabolism*; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D016213:Cyclins / Q000235:genetics / Q000378:metabolism; D004441:Ecdysterone / Q000031:analogs & derivatives / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D016193:G1 Phase; D006367:HeLa Cells; D006801:Humans; D020930:MAP Kinase Kinase Kinases / Q000378:metabolism*; D008954:Models, Biological; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009570:Nitriles / Q000494:pharmacology; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: C120227:2-(2-chloro-4-iodophenylamino)-N-cyclopropylmethoxy-3,4-difluorobenzamide; D001549:Benzamides; D002070:Butadienes; D016213:Cyclins; D004791:Enzyme Inhibitors; D009570:Nitriles; D016376:Oligonucleotides, Antisense; D011518:Proto-Oncogene Proteins; D016160:Retinoblastoma Protein; C113580:U 0126; D004441:Ecdysterone; C008999:ponasterone A; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C495900:CDK4 protein, human; D051357:Cyclin-Dependent Kinase 2; D051358:Cyclin-Dependent Kinase 4; D018844:Cyclin-Dependent Kinases; D020930:MAP Kinase Kinase Kinases