ipi-926 and Pancreatic-Neoplasms

In mouse models of pancreatic cancer, IPI-926, an oral Hedgehog inhibitor, increases chemotherapy delivery by depleting tumor-associated stroma. This multicenter phase Ib study evaluated IPI-926 in combination with FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan, oxaliplatin) in patients with advanced pancreatic cancer.. Patients were treated with once-daily IPI-926 plus FOLFIRINOX. A 3 + 3 dose escalation design was used, with cohort expansion at the maximum tolerated dose. A subset of patients underwent perfusion computed tomography to assess changes in tumor perfusion.. The maximum tolerated dose was identified 1 dose level below standard FOLFIRINOX. Common treatment-related adverse events included liver function test abnormalities, neuropathy, nausea/vomiting, and diarrhea. Objective response rate was high (67%), and patients receiving IPI-926 maintenance showed further declines in CA19-9 levels even after FOLFIRINOX discontinuation. Treatment did not result in consistent increases in tumor perfusion. The study closed early when a separate phase II trial of IPI-926 plus gemcitabine indicated detrimental effects of this combination.. This is the first study to demonstrate the feasibility of using FOLFIRINOX as the chemotherapeutic backbone in a clinical trial design. Although robust antitumor activity and acceptable safety were observed with the addition of IPI-926 to this regimen, future development of Hedgehog inhibitors in pancreatic cancer seems unlikely.

Topics: Adenocarcinoma; Aged; Antineoplastic Combined Chemotherapy Protocols; CA-19-9 Antigen; Camptothecin; Diarrhea; Dose-Response Relationship, Drug; Feasibility Studies; Female; Fluorouracil; Hedgehog Proteins; Humans; Irinotecan; Kaplan-Meier Estimate; Leucovorin; Male; Middle Aged; Nausea; Nervous System Diseases; Organoplatinum Compounds; Oxaliplatin; Pancreatic Neoplasms; Signal Transduction; Treatment Outcome; Veratrum Alkaloids; Vomiting

Pancreatic ductal adenocarcinoma (PDA) is among the most lethal human cancers in part because it is insensitive to many chemotherapeutic drugs. Studying a mouse model of PDA that is refractory to the clinically used drug gemcitabine, we found that the tumors in this model were poorly perfused and poorly vascularized, properties that are shared with human PDA. We tested whether the delivery and efficacy of gemcitabine in the mice could be improved by coadministration of IPI-926, a drug that depletes tumor-associated stromal tissue by inhibition of the Hedgehog cellular signaling pathway. The combination therapy produced a transient increase in intratumoral vascular density and intratumoral concentration of gemcitabine, leading to transient stabilization of disease. Thus, inefficient drug delivery may be an important contributor to chemoresistance in pancreatic cancer.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Proliferation; Deoxycytidine; Disease Models, Animal; Drug Resistance, Neoplasm; Gemcitabine; Hedgehog Proteins; Humans; Kruppel-Like Transcription Factors; Mice; Neoplasm Transplantation; Neovascularization, Pathologic; Pancreatic Neoplasms; Receptors, G-Protein-Coupled; Signal Transduction; Smoothened Receptor; Stromal Cells; Veratrum Alkaloids; Zinc Finger Protein GLI1

In a recent issue of Cell, Silva and colleagues reported the identification of CYFIP1, a member of the actin-assembly-promoting Scar/WAVE complex, as an invasion suppressor in epithelial cancers. This study challenges ideas about the role of actin in cancer invasion.

Topics: Actins; Animals; Cell Line, Tumor; Hedgehog Proteins; Humans; Magnetic Resonance Imaging; Mice; Mutation; Neoplasm Invasiveness; Pancreatic Neoplasms; Perfusion; Signal Transduction; Survival Analysis; United States; Veratrum Alkaloids

Topics: Animals; Antimetabolites, Antineoplastic; Carcinoma, Pancreatic Ductal; Deoxycytidine; Gemcitabine; Hedgehog Proteins; Mice; Neoplasm Proteins; Pancreatic Neoplasms; Veratrum Alkaloids

Topics: Animals; Disease Models, Animal; Hedgehog Proteins; Humans; Mice; Pancreatic Neoplasms; Receptors, G-Protein-Coupled; Signal Transduction; Smoothened Receptor; Veratrum Alkaloids