- Browse by Author
Browsing by Author "Donoho, Gregory P."
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item 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 MedicineAlthough 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.Item Phase Ib/II Study of Enzalutamide with Samotolisib (LY3023414) or Placebo in Patients with Metastatic Castration-Resistant Prostate Cancer(American Association for Cancer Research, 2022) Sweeney, Christopher J.; Percent, Ivor J.; Babu, Sunil; Cultrera, Jennifer L.; Mehlhaff, Bryan A.; Goodman, Oscar B.; Morris, David S.; Schnadig, Ian D.; Albany, Costantine; Shore, Neal D.; Sieber, Paul R.; Guba, Susan C.; Zhang, Wei; Wacheck, Volker; Donoho, Gregory P.; Szpurka, Anna M.; Callies, Sophie; Lin, Boris Kin; Bendell, Johanna C.; Medicine, School of MedicinePurpose: To report efficacy and safety of samotolisib (LY3023414; PI3K/mTOR dual kinase and DNA-dependent protein kinase inhibitor) plus enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) following cancer progression on abiraterone. Patients and methods: In this double-blind, placebo-controlled phase Ib/II study (NCT02407054), following a lead-in segment for evaluating safety and pharmacokinetics of samotolisib and enzalutamide combination, patients with advanced castration-resistant prostate cancer with progression on prior abiraterone were randomized to receive enzalutamide (160 mg daily)/samotolisib (200 mg twice daily) or placebo. Primary endpoint was progression-free survival (PFS) assessed by Prostate Cancer Clinical Trials Working Group criteria (PCWG2). Secondary and exploratory endpoints included radiographic PFS (rPFS) and biomarkers, respectively. Log-rank tests assessed treatment group differences. Results: Overall, 13 and 129 patients were enrolled in phase Ib and II, respectively. Dose-limiting toxicity was not reported in patients during phase Ib and mean samotolisib exposures remained in the targeted range despite a 35% decrease when administered with enzalutamide. In phase II, median PCWG2-PFS and rPFS was significantly longer in the samotolisib/enzalutamide versus placebo/enzalutamide arm (3.8 vs. 2.8 months; P = 0.003 and 10.2 vs. 5.5 months; P = 0.03), respectively. Patients without androgen receptor splice variant 7 showed a significant and clinically meaningful rPFS benefit in the samotolisib/enzalutamide versus placebo/enzalutamide arm (13.2 months vs. 5.3 months; P = 0.03). Conclusions: Samotolisib/enzalutamide has tolerable side effects and significantly improved PFS in patients with mCRPC with cancer progression on abiraterone, and this may be enriched in patients with PTEN intact and no androgen receptor splice variant 7.