Browsing by Author "Lallena, Maria Jose"

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    Aurora A–Selective Inhibitor LY3295668 Leads to Dominant Mitotic Arrest, Apoptosis in Cancer Cells, and Shows Potent Preclinical Antitumor Efficacy
    (AACR, 2019-12) Du, Jian; Yan, Lei; Torres, Raquel; Gong, Xueqian; Bian, Huimin; Marugán, Carlos; Boehnke, Karsten; Baquero, Carmen; Hui, Yu-Hua; Chapman, Sonya C.; Yang, Yanzhu; Zeng, Yi; Bogner, Sarah M.; Foreman, Robert T.; Capen, Andrew; Donoho, Gregory P.; Van Horn, Robert D.; Barnard, Darlene S.; Dempsey, Jack A.; Beckmann, Richard P.; Marshall, Mark S.; Chio, Li-Chun; Qian, Yuewei; Webster, Yue W.; Aggarwal, Amit; Chu, Shaoyou; Bhattachar, Shobha; Stancato, Louis F.; Dowless, Michele S.; Iversen, Phillip W.; Manro, Jason R.; Walgren, Jennie L.; Halstead, Bartley W.; Dieter, Matthew Z.; Martinez, Ricardo; Bhagwat, Shripad V.; Kreklau, Emiko L.; Lallena, Maria Jose; Ye, Xiang S.; Patel, Bharvin K. R.; Reinhard, Christoph; Plowman, Gregory D.; Barda, David A.; Henry, James R.; Buchanan, Sean G.; Campbell, Robert M.; Pediatrics, School of Medicine
    Although Aurora A, B, and C kinases share high sequence similarity, especially within the kinase domain, they function distinctly in cell-cycle progression. Aurora A depletion primarily leads to mitotic spindle formation defects and consequently prometaphase arrest, whereas Aurora B/C inactivation primarily induces polyploidy from cytokinesis failure. Aurora B/C inactivation phenotypes are also epistatic to those of Aurora A, such that the concomitant inactivation of Aurora A and B, or all Aurora isoforms by nonisoform–selective Aurora inhibitors, demonstrates the Aurora B/C-dominant cytokinesis failure and polyploidy phenotypes. Several Aurora inhibitors are in clinical trials for T/B-cell lymphoma, multiple myeloma, leukemia, lung, and breast cancers. Here, we describe an Aurora A–selective inhibitor, LY3295668, which potently inhibits Aurora autophosphorylation and its kinase activity in vitro and in vivo, persistently arrests cancer cells in mitosis, and induces more profound apoptosis than Aurora B or Aurora A/B dual inhibitors without Aurora B inhibition–associated cytokinesis failure and aneuploidy. LY3295668 inhibits the growth of a broad panel of cancer cell lines, including small-cell lung and breast cancer cells. It demonstrates significant efficacy in small-cell lung cancer xenograft and patient-derived tumor preclinical models as a single agent and in combination with standard-of-care agents. LY3295668, as a highly Aurora A–selective inhibitor, may represent a preferred approach to the current pan-Aurora inhibitors as a cancer therapeutic agent.
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    Preclinical characterization of the CDK4/6 inhibitor LY2835219: in-vivo cell cycle-dependent/independent anti-tumor activities alone/in combination with gemcitabine
    (Springer, 2014) Gelbert, Lawrence M.; Cai, Shufen; Lin, Xi; Sanchez-Martinez, Concepcion; del Prado, Miriam; Lallena, Maria Jose; Torres, Raquel; Ajamie, Rose T.; Wishart, Graham N.; Flack, Robert Steven; Neubauer, Blake Lee; Young, Jamie; Chan, Edward M.; Iversen, Philip; Cronier, Damien; Kreklau, Emiko; de Dios, Alfonso; Pediatrics, School of Medicine
    The G1 restriction point is critical for regulating the cell cycle and is controlled by the Rb pathway (CDK4/6-cyclin D1-Rb-p16/ink4a). This pathway is important because of its inactivation in a majority of human tumors. Transition through the restriction point requires phosphorylation of retinoblastoma protein (Rb) by CDK4/6, which are highly validated cancer drug targets. We present the identification and characterization of a potent CDK4/6 inhibitor, LY2835219. LY2835219 inhibits CDK4 and CDK6 with low nanomolar potency, inhibits Rb phosphorylation resulting in a G1 arrest and inhibition of proliferation, and its activity is specific for Rb-proficient cells. In vivo target inhibition studies show LY2835219 is a potent inhibitor of Rb phosphorylation, induces a complete cell cycle arrest and suppresses expression of several Rb-E2F-regulated proteins 24 hours after a single dose. Oral administration of LY2835219 inhibits tumor growth in human tumor xenografts representing different histologies in tumor-bearing mice. LY2835219 is effective and well tolerated when administered up to 56 days in immunodeficient mice without significant loss of body weight or tumor outgrowth. In calu-6 xenografts, LY2835219 in combination with gemcitabine enhanced in vivo antitumor activity without a G1 cell cycle arrest, but was associated with a reduction of ribonucleotide reductase expression. These results suggest LY2835219 may be used alone or in combination with standard-of-care cytotoxic therapy. In summary, we have identified a potent, orally active small-molecule inhibitor of CDK4/6 that is active in xenograft tumors. LY2835219 is currently in clinical development.