Breast cancer, the most common cancer in women, will kill about 40,000 patients this year, largely due to metastasis. But now, researchers may have a way to put the brakes on that process. A Danish team says it has zeroed in on a "molecular switch" that may help control metastases and could become a biomarker for diagnosing and treating cancer.
According to findings published in the journal Molecular Cell, researchers at the University of Copenhagen have identified molecular mechanisms they believe play a key role in breast cancer cell growth and spread. The team investigated FGFR2b, a fibroblast growth factor receptor essential in internal organ development. Through a large-scale analysis of proteins, researchers came across two signaling proteins that bind to the receptor to affect cell division and control cell movement, processes that could spur cancer metastases if they spin out of control.
"In simple terms, we have mapped the molecular switch on the receptor that turns two important biological processes on and off, respectively," lead researcher Jesper Velgaard Olsen told Medical News Today. "We have, in other words, pinpointed the binding site that can cause increased spreading of breast cancer cells and thus the development of metastases."
While the investigation dealt with only human cancer cells and mouse tissue, Olsen said he thinks FGFR2b could become a new biomarker for cancer diagnosis and that eventually, the team's findings will help improve customized treatments for human breast cancers.
"The more we know about the body's transmission systems, the better we become at targeting medical treatment. Hopefully, we will in future be able to offer customized treatment based on the individual patient's cellular profile," he said.
Separately, researchers analyzing an international trial of locally advanced or metastatic HER2-positive breast cancer found that levels of certain proteins in patients may indicate who will most benefit from adding everolimus to Genentech's HER2-targeting antibody trastuzumab plus vinorelbine. In women with tumors resistant to trastuzumab, those with low PTEN levels enjoyed a median progression-free survival gain of about 18 weeks, while those with high pS6 levels saw progression-free survival extended by about 12 weeks.
But Clifford Hudis, president of the American Society of Clinical Oncology (ASCO) and chief of the Breast Cancer Service at Memorial Sloan-Kettering Cancer Center, told OncLive he believed the biomarker analysis results from the trial were, at most, a base for generating hypotheses. "We are splitting up a nearly negative trial, and we have to take these biomarker results with a grain of salt," he said.