Optimized multifunctional peptide based magnetic biointerface for selective capture and sensitive detection of circulating tumor cells in breast cancer

The detection of circulating tumor cells (CTCs) has emerged as a promising approach for the early diagnosis, therapeutic monitoring, and prognosis of malignant tumors. In this study, we present a novel magnetic nanoparticle (MP) functionalized with dual recognition peptides targeting the epithelial cell adhesion molecule (EpCAM) and human epidermal growth factor receptor 2 (HER2). Additionally, bovine serum albumin (BSA), an anti-fouling agent, is employed onto MP, effectively preventing the non-specific adhesion of platelets and proteins. This multifunctional peptide based magnetic biointerface (MPMB) platform effectively captures breast cancer cells in model systems and isolates CTCs from the blood of breast cancer patients. CTC enumeration of peripheral blood samples from 40 breast cancer patients, 30 benign breast tumor patients, and 30 healthy donors revealed a 70 % positivity rate in breast cancer patients (28/40), 6.7 % in benign breast tumor patients (2/30), and no positivity in healthy donors (0/30). CTC counts were significantly higher in breast cancer patients with advanced stages, particularly in those with distant metastasis, compared to early-stage patients ( p  < 0.05). Moreover, among 10 breast cancer patients with positive CTC detection prior to surgery, 6 showed negative CTC results post-surgery. These findings indicate that the MPMB approach provides a simple, flexible, and efficient platform for monitoring therapeutic efficacy and evaluating prognosis in breast cancer patients undergoing treatment.