Liquid biopsy test identifies androgen receptor protein expression in circulating tumor cells in women with metastatic breast cancer.

Epic Sciences along with researchers at the MD Anderson Cancer Center (MDA) have recently published their findings on androgen receptor (AR) protein expression in circulating tumor cells (CTCs) in patients with metastatic breast cancer in PLOS One. The publication, the most comprehensive today in characterizing the AR protein in CTCs of patients with breast cancer, identifies subclonal heterogeneity of AR protein.

In recent clinical trials, AR signaling inhibitors, Zytiga® and Xtandi®, approved in metastatic prostate cancer, have demonstrated potential benefits in a portion of women with metastatic breast cancer. However, current tools to identify patients who may benefit from AR signaling inhibitors are invasive and suffer from accuracy errors in predicting patient response.

In addition to profiling CTCs for AR, estrogen receptor and HER2 biomarkers were also characterized. Protein biomarker heterogeneity was observed in many patients. To support the hypothesis of tumor heterogeneity, single cell genomic profiling identified genomic heterogeneity associated with the protein heterogeneity which has been identified as a resistance marker in cancer.

“Subclonal AR protein expression could both identify patients who may resist targeted therapy and at the same time, explain partial response to AR signaling inhibition,” said Ryan Dittamore, chief of medical innovation at Epic Sciences and co-author on the study. “With our academic and biopharma partners, we are expanding our understanding of tumor heterogeneity in metastatic breast cancer to improve tools for patient selection to improve patient survival.”

This study, led by Naoto T. Ueno, M.D., Ph.D., executive director at The University of Texas MDA Morgan Welch Inflammatory Breast Cancer Research Program and Clinic, utilized Epic Sciences non-biased enrichment free platform to characterize CTCs in blood samples. The Epic Sciences platform is currently utilized in more than 175 clinical studies in 12 different cancers.

About Epic Sciences

At Epic Sciences, we develop clinically proven predictive tests to detect and monitor cancer at the individual cell level. With a proprietary rare-cell detection engine, we provide insights to clinical, biotech, pharmaceutical and academic teams on how cancer emerges, mutates and remits so they can make pivotal decisions at every point in patient treatment with greater certainty. Recognizing the unique nature of each person’s cancer, we offer truly personalized diagnostic tests, while being non-invasive for the patient.

We have developed the first clinically proven predictive test for metastatic castration-resistant prostrate cancer (mCRPC), the Epic AR-V7 test. Using the same rare-cell detection platform and Epic’s biobank of over 30,000 blood samples, each profiled with predictive biomarkers, we partner with leading pharmaceutical and biotechnology companies, major cancer centers, the National Cancer Institute (NCI), and the National Institutes of Health (NIH) to pursue additional predictive tests for breast, ovarian, colon and other cancers and diseases. Our mission is to revolutionize cancer care and therapies to make them as precise, safe and life-sustaining as humanly possible.

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