NCCS, SGH, and Clearbridge BioMedics Examine the Heterogeneity of CTCs in Breast Cancer Patients

The National Cancer Centre Singapore, Singapore General Hospital (Department of Pathology), and Clearbridge BioMedics have collaborated on a research project that examines circulating tumour cells from local breast cancer patients. Preliminary data from the study revealed heterogeneity in the circulating tumour cells (CTCs) isolated from each patient’s blood samples and tumour biopsy or surgical specimens. Heterogeneity refers to the diversity or the differences between different tumours, and in this case, the differences among the different circulating tumour cells at the individual cell level. These results were presented at the American Association for Cancer Research (AACR) Annual Meeting held in New Orleans, USA. Breast cancers with increased levels of human epidermal growth factor receptor 21 (HER2) protein driven by the HER2 gene tend to grow and spread more aggressively than other breast cancers. However, the availability of anti-HER2 therapies such as trastuzumab has improved treatment outcomes significantly. Patients are normally selected for anti-HER2 targeted therapy according to the tumour HER2 levels based on a protein expression test called immunohistochemistry, or on a gene test called FISH (fluorescence in situ hybridisation) that measures the number of copies of the HER2 gene. Tumours which demonstrate HER2 protein overexpression or HER2 gene amplification benefit from HER2-targeted therapies. In this study, researchers examined HER2 heterogeneity in CTCs obtained from the blood of 26 breast cancer patients. CTCs were successfully identified and recovered from blood samples of patients with both HER2-positive and HER2-negative breast cancers using the label-free ClearCell FX1 System. The CTCs from these samples were found to exhibit certain molecular characteristics, such as chromosome 17 polysomy, whereby there are increased numbers of chromosome 17 carrying HER2 and other genes. “This study demonstrated that CTCs capture the molecular heterogeneity of breast cancer at the cellular level. Some of the CTCs from patients with HER2-negative tumours were found to be HER2-positive with increased copy numbers of the HER2 gene, while some of the CTCs from patients with HER2-positive tumours did not have increased numbers of HER2 gene. The presence of HER2-positive CTCs in patients, along with tissue biopsies which are commonly used to determine if a patient is HER2- positive, can potentially help determine the appropriate treatment regime. By leveraging upon our proprietary ClearCell® FX1 System, which is a label-free automated system to isolate intact and viable CTCs, Clearbridge BioMedics is happy to support such cutting edge research that aims to provide new insights leading to improved cancer management,” said Mr Johnson Chen, Managing Director and Founder Clearbridge BioMedics.

Copyright © 2013 All rights reserved. Content and images are meant for practicing medical doctors, allied health care professionals and other establishments in the medical industry. Reproduction or redistribution of any content and images, is prohibited without the prior written consent of Ezyhealth Media Pte Ltd.