Quantification of Breast Cancer Cells in Peripheral Blood Samples by Real-Time RT-PCR

Abstract

Background: Circulating tumour cells (CTCs) are cells that have detached from a primary tumour, circulate in the peripheral blood, and are considered to be the main root of distant metastases. We present a method for the detection of CTCs by real-time PCR on different cytokeratin markers. Materials and Methods: Blood samples of a healthy donor were mixed with specific numbers of cells from different breast carcinoma cell line cells. RNA was isolated from the samples and transcribed into cDNA. TaqMan real-time PCR for cytokeratins 8, 18 and 19 was carried out and was correlated to that of 18S. Results: Cytokeratin gene expression increased in all samples, when as few as 10 tumour cells were added. In the CAMA-1 cell line, the increase was even greater the more cells were added. Conclusion: By this methodology, cells from mammary carcinoma cell lines can be detected in blood samples. Its benefit will be validated in samples from patients with breast cancer.