Modified C-type natriuretic peptide normalizes tumor vasculature and improves solid tumor therapies

Deficit of oxygen and nutrients in the tumor microenvironment (TME) triggers abnormal angiogenesis that produces dysfunctional and leaky blood vessels, which fail to adequately perfuse tumor tissues. Resulting hypoxia, exacerbation of metabolic problems and generation of immunosuppressive TME undermine the efficacy of cancer treatment. These problems can be partially alleviated by angiogenesis inhibitors. Here we propose an alternative agonist-based normalization approach utilizing a derivative of the C-type natriuretic peptide (dCNP). This well-tolerated agent stimulated formation of highly functional tumor blood vessels to reduce hypoxia. Administration of dCNP also inhibited stromagenesis and reinvigorated the anti-tumor immune responses. Treatment with dCNP decelerated growth of primary tumors and suppressed their metastases. Moreover, inclusion of dCNP into the chemo-, radio- or immune-therapeutic regimens increased their efficacy against solid tumors. These results demonstrate the proof of principle for using activators of normalized angiogenesis to improve therapies against solid tumors and characterize dCNP as the first in class amongst such agents. Overall design: To investigate the role of dCNP on tumor microenvironment reprograming, we injecetd MC38 cancer cells into C57BL/6J mice and these tumor bearing mice were treated with vehicle or dCNP for 10 days. Afterward, tumors were collecetd and RNA was extracted for bulk RNA sequencing.