Opening a Door into Solid Tumors

The irregular and leaky vasculature of tumors has been a major obstacle to the effective delivery of chemotherapeutics and immunotherapies to the cancerous tissues they target.¹ A paper in <em>Nature</em> now suggests that inhibiting regulator of G protein signaling 5, a protein upregulated in a variety of cancers,² could block tumor-induced vascular remodeling and enhance delivery of therapeutics.³

In the new study by Ruth Ganss of the Western Australian Institute for Medical Research and colleagues, the researchers knocked out regulator of G protein signaling 5 (Rgs5) in a murine model of pancreatic islet cell carcinogenesis, a model previously used in her lab that had shown overexpression of Rgs5 in the tumor vasculature, specifically in pericytes in the vascular bed.⁴ Pancreatic tumors in the resulting Rgs5-deficient mice had significantly improved oxygenation and significantly less vascular leakiness compared with tumors in wild-type mice (p=0.008)...