 Biocept Inc NASDAQ:BIOC said it is participating in a study evaluating biomarkers associated with central nervous system CNS metastasis in patients with metastatic breast cancer and brain metastases andor leptomeningeal disease. The study will look at cerebrospinal fluid tumor and the immune cell microenvironment to better understand treatment response, prognosis, and treatment resistance that may improve the management of CNS disease in patients with metastatic breast cancer, the company said. 