title: Inhibition of PDGFR phosphorylation and Src and Akt activity by GN963 leads to therapy of human pancreatic cancer growing orthotopically in nude mice.
abstract: GN963 is a tyrosine kinase inhibitor with activity against platelet-derived growth factor receptor (PDGFR) and Src kinases. We determined whether oral administration of GN963, alone or in combination with gemcitabine produces therapy against L3.6pl human pancreatic cancer cells growing orthotopically in nude mice. The optimal biological dosage of oral GN963 was determined to be 100 mg/kg every 48 h. Seven days after injection of L3.6pl cells into the pancreas of nude mice, mice (n=10) were treated with vehicle (control), thrice-weekly oral GN963 (100 mg/kg), twice-weekly intraperitoneal gemcitabine (100 mg/kg), or GN963 plus gemcitabine. Treatment with gemcitabine did not significantly differ from control. In contrast, treatment with GN963 (100 mg/kg) or GN963 plus gemcitabine produced a 52% and 81% decrease in tumor volume, respectively. GN963 plus gemcitabine completely inhibited the incidence of liver metastasis. Administration of GN963 inhibited PDGFR phosphorylation in both tumor and tumor-associated endothelial cells, decreased Src and Akt kinase activity in tumor cells, decreased microvessel density, and decreased tumor cell proliferation, while increasing apoptosis of tumor and tumor-associated endothelial cells. Collectively, these data indicate that targeting PDGFR, Src, and Akt on tumor and tumor-associated endothelial cells may be an effective therapy for human pancreatic carcinoma.
authors.affiliation: Cancer Research Institute of M.D. Anderson Cancer Center Orlando, FL 32806, USA. cheryl.baker@orhs.org
authors.forename: Cheryl H
authors.initials: CH
authors.lastname: Baker
authors.forename: Jose G
authors.initials: JG
authors.lastname: Trevino
authors.forename: Justin M
authors.initials: JM
authors.lastname: Summy
authors.forename: Fahao
authors.initials: F
authors.lastname: Zhang
authors.forename: Alexis
authors.initials: A
authors.lastname: Caron
authors.forename: Mark
authors.initials: M
authors.lastname: Nesbit
authors.forename: Gary E
authors.initials: GE
authors.lastname: Gallick
authors.forename: Isaiah J
authors.initials: IJ
authors.lastname: Fidler
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D006801:Humans; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D011810:Quinoxalines / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D019061:src-Family Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D000970:Antineoplastic Agents; D047428:Protein Kinase Inhibitors; D011810:Quinoxalines; C521618:trans-4-(6,7-dimethoxyquinoxalin-2ylamino)cyclohexanol sulfate; D003841:Deoxycytidine; D020797:Receptor, Platelet-Derived Growth Factor beta; D019061:src-Family Kinases; D051057:Proto-Oncogene Proteins c-akt; D000093542:Gemcitabine