Identification of Cancer Cell Addiction Can Lead to More Effective Therapies

If cancerous tumors have an addiction to a gene, an inhibitor can be administered that can stop cell growth.

A blood test can test stomach cancer cells for addiction to a gene that increases cell growth, and can help predict which patients may respond well to a novel drug.

Researchers found that stomach cancer cells with multiple copies of FGFR2 gene were more likely to respond to an FGR inhibitor since the cells had become reliant on the gene for growth, according to a study published in Cancer Discovery. Researchers tested the potency of AZD4547, a FGFR2 inhibitor, in 341 patients with stomach and breast cancer included in a phase 2 clinical trial.

Researchers discovered that multiple copies of FGFR2 were found in 9% of stomach cancer biopsies. Out of the 9 patients, 3 responded to the treatment and responded for about 6.6 months, according to the study.

Approximately 18% of breast cancers had multiple copies of FGFR2, a sister gene, but were not susceptible to the drug. To gain an understanding of why the drug worked in FGFR2 tumors but not in other FGFR tumors, additional research was conducted.

It was found that FGFR2 takes over control of molecular pathways that help cancer spread, according to the study. Researchers also found that some stomach tumors become reliant upon high levels of the gene.

Investigators believe that exploiting these gene addictions is a quick way to develop targeted and effective treatments for patients.

"Our study has identified a potential new treatment for a subset of patients with gastric cancer, and has explained why some gastric cancers were responding to treatment while others did not. We were able to design a blood test to screen for patients who were most likely to benefit from an FGFR2 inhibitor, helping us to target drug therapy at those patients who were most likely to benefit,” concluded study co-leader Nicholas Turner, PhD. "The research helps shed light on how tumors can become addicted to certain cancer genes and shows how we can treat the disease effectively by taking advantage of these weak points in cancer's armory."