Relationship between detection of circulating tumor cells and molecular subtypes in breast cancer patients

Abstract

Objective To investigate the correlation between circulating tumor cells (CTCs) and the predefined molecular classification of patients with breast cancer.Methods We used real-time quanti-tative reverse transcription-polymerase chain reaction (RT-qPCR) to detect cytokeratin 19 (CK19),human mammaglobin (hMAM),and small breast epithelial mucin (SBEM) mRNA expression levels in 285 cases of breast cancer and 123 controls.Statistical analyses were additionally performed to examine the correlation between the mRNA expression levels of these markers with the clinicopathological features of breast cancer patients.Results The sensitivity of these three mRNA markers of the patients with breast cancer was 33.3％,17.9％,and 18.2％ respectively,which was significantly higher than the control group (P ＜ 0.05).The sensitivity of these three markers combined was 47％,which was significantly higher than that of single marker detection (P ＜ 0.05).However,no significant difference in CTC detection was noted among the predefined molecular classifications.Statistical analysis demonstrated that high expression levels of CTC were correlated with the age and menopause status (P ＜ 0.05).In addition,overexpression of these three mRNA markers was positively correlated with tumor size (P ＜ 0.05).Conclusion Combined detection of three markers (CK19,hMAM and SBEM) based on a RT-qPCR platform has higher sensitivity to detect CTC in peripheral blood of breast cancer patients.Although CTC have no clear correla-tion with breast cancer molecular subgroups,but close correlation with age,postmenopausal status and tumor size of patients with breast cancer. Key words: Breast cancer; Circulating tumor cells; Molecular classification