Trastuzumab-cisplatin conjugates for targeted delivery of cisplatin to HER2-overexpressing cancer cells

Cisplatin is widely used for the treatment of numerous types of cancer, while its application is limited by the adverse side effects for its poor selectivity. Trastuzumab is a highly targeting protein to HER2 protein, and it is usually combined with paclitaxel or cisplatin for the treatment of HER2-overexpressing breast cancer. In the present work, we used trastuzumab as a targeting carrier for platinum drug delivery. In ELISA assays and immunofluorescence study, Tmab-1 exhibited high and specific binding affinity to HER2 protein and HER2-overexpressing SK-BR-3 cells. In cytotoxicity test, Tmab-1 showed promising antiproliferative activity to SK-BR-3 cells, while it hardly inhibited the growth of MCF-7 cells and MDA-MB-231 cells. The cell cycle arrest study showed Tmab-1 induced the cell cycle arrest mainly at G2/M phase. This work indicates that trastuzumab is an effective and potential targeting carrier for drug delivery.