Protein Biomarkers to Gauge Cancer Response to Chemo Identified

Protein Biomarkers to Gauge Cancer Response to Chemo Identified

Investigators using targeted proteomics — a technique to detect proteins of interest — on samples of ovarian cancer found a wide variety of biomarkers that might help predict which chemotherapies patients are more likely to respond to, the precision medicines company mProbe reported.

Identifying these tumor biomarkers is crucial not only to spotting potential targets for future therapies, but also for enabling physicians and patients to make more informed decisions and avoid unnecessary chemo use, the investigators said.

Findings were presented in the poster, “Molecular profiling of ovarian cancer by targeted proteomics to inform personalized therapy,” presented at the American Association for Cancer Research (AACR) Virtual Annual Meeting II, June 22-24, 2020.

Chemotherapy is the mainstay treatment for ovarian cancer, but it is not a personalized treatment in the sense that does not routinely account for the presence or levels of specific tumor biomarkers in individuals.

This means that patients can go through unnecessary courses of chemotherapy, with associated side effects, and risk that the best possible therapy is given only after repeat failures.

Researchers at mProbe reported on a targeted proteomic analysis performed on ovarian cancer samples. Its aim was to generate information that could be useful in developing personalized treatments.

“It’s critical to get the most efficacious therapy to patients quickly,” Sheeno Thyparambil, senior director of Research and Development at mProbe, said in a press release.

“Quantification of protein biomarkers will provide critical information to the oncologist for better informed decisions to reduce the trial and error that can accompany cancer care,” Thyparambil added.

They used OncoOmicsDx, mProbe’s proprietary quantitative protein biomarker method, to measure the levels of 72 protein biomarkers in 169 ovarian cancer samples at the company’s CLIA certified laboratory.

Most samples had varying levels of resistance markers for cyclophosphamide (87%), platinum agents (70%), and taxanes (71%), the analysis found.

These samples also contained different levels of response biomarkers for several common chemotherapy agents for ovarian cancer, including irinotecan/topotecan (97%), doxorubicin (50%), and gemcitabine (42%).

Also identified were new chemotherapy agents, like temozolomide, that could be promising for some patients, as well as varying levels of receptors that treatments from the class of antibody drug conjugates could bind to, including those targeting mesothelin (66%), the folate receptor alpha (74%), and HER2 (56%).

“The ability to multiplex 72 protein biomarkers from [fixed sample] sections provides immense actionable information on clinical treatment or for patient stratification for clinical trials,” the investigators wrote.