Human epidermal growth factor receptor 2 (HER2)-specifc chimeric antigen receptor (CAR) for tumor immunotherapy; recent progress

Due to the overexpression or amplifcation of human epidermal growth factor receptor 2 (HER2) with poor prognosis in a myriad of human tumors, recent studies have focused on HER2-targeted therapies. Deregulation in HER2 signal- ing pathways is accompanied by sustained tumor cells growth concomitant with their migration and also tumor angiogenesis and metastasis by stimulation of proliferation of a network of blood vessels. A large number of studies have provided clear evidence that the emerging HER2-directed treatments could be the outcome of patients sufer- ing from HER2 positive breast and also gastric/gastroesophageal cancers. Thanks to its great anti-tumor competence, immunotherapy using HER2-specifc chimeric antigen receptor (CAR) expressing immune cell has recently attracted increasing attention. Human T cells and also natural killer (NK) cells can largely be found in the tumor microenviron- ment, mainly contributing to the tumor immune surveillance. Such properties make them perfect candidate for genetically modifcation to express constructed CARs. Herein, we will describe the potential targets of the HER2 signaling in tumor cells to clarify HER2-mediated tumorigenesis and also discuss recent fndings respecting the HER2- specifc CAR-expressing immune cells (CAR T and CAR NK cell) for the treatment of HER2-expressing tumors.