4056 Background: Recent advances in pancreatic cancer research implicate the involvement of several heparin-binding growth factors (such as HGF, HB-EGF, PDGF, hedgehogs, and TGFs) that control tumor-stroma interactions. We have rationally designed a heparan sulfate mimetic, M402, which has been previously shown to affect tumor progression and metastasis through disruption of multiple pathways. We hypothesized that M402 could modulate tumor-stroma interactions and enhance the efficacy of gemcitabine, and evaluated its efficacy in two preclinical models. Methods: A genetically engineered mouse model (GEMM; KrasLSLG12D p53LSLR172H) featuring spontaneous pancreatic tumor formation and metastasis assessed M402’s effect on tumorigenesis and metastasis. The orthotopic Capan-2 model in nude mice evaluated the effect of M402 on desmoplasia, a fibrotic response that hinders effective delivery of chemotherapeutics, via inhibition of sonic hedgehog (SHH) signaling in fibroblasts and stellate cells. In both models, M402 was studied as monotherapy and with gemcitabine. Results: In the GEMM, M402 significantly prolonged survival in combination with gemcitabine while each monotherapy showed modest efficacy. M402, alone and in combination, also reduced metastases and local invasion and inhibited epithelial-to-mesenchymal transition. In the Capan-2 model, gemcitabine was increasingly less effective as desmoplasia progressed over time. The addition of M402 to gemcitabine increased its efficacy with respect to primary tumor burden. Metastasis, invasion, and surrounding fibrotic lesions appeared particularly impacted by the combination treatment. M402 was also effective as monotherapy with dose-dependency, which correlated with reduced SHH signaling. Conclusions: M402 can modulate tumor-stroma interactions involved in the metastatic and desmoplastic pathways in two pancreatic cancer models supporting the translation of these findings into a clinical study. A first-in-human study is planned that will evaluate the safety, pharmacokinetics, efficacy, and biomarker profiles of escalating M402 doses in combination with gemcitabine in patients with metastatic pancreatic cancer.
Wild-Type Hras Suppresses the Earliest Stages of Tumorigenesis in a Genetically Engineered Mouse Model of Pancreatic Cancer
