Novel Vascular Technique Being Studied in Advanced Ovarian Cancer
Posted: Monday, December 17, 2018
According to a study published in Clinical Cancer Research, normalizing the vasculature of an advanced-stage ovarian tumor prior to delivering immunotherapy can promote its regression. This challenges the current standard of modifying the tumor vasculature, which is to induce thrombosis in an attempt to starve the tumor.
“When you cut off a tumor’s blood supply, it often becomes more aggressive,” said study author Jim Petrik, PhD, of the University of Guelph, in a university press release. “We developed an approach where you only kill off the dysfunctional blood vessels. The result is a smaller, calmer tumor with a good blood supply. Once you have established an effective vascular system, you can use that system to get treatment to the tumor.”
For this study, researchers used a mouse model of advanced-stage epithelial ovarian cancer. The mice were pretreated with either 3TSR (4 mg/kg/day) monotherapy or 3TSR followed by an oncolytic, fusogenic Newcastle disease virus (F3aa; 1.0 × 108 PFU). Mice treated with 3TSR monotherapy experienced normalized tumor vasculature, enhanced blood flow to the tumor, and the beginning of disease regression. Those treated with combination therapy experienced the greatest reduction in tumor mass as well as enhanced movement of immunologic cells into the primary tumor.
“This study provides proof of principle that vascular normalization can potentiate oncolytic viruses–based immunotherapy for the treatment of both primary and metastatic [epithelial ovarian cancer],” the authors concluded.