MYCN and breast cancer: Layer JP, et al. reported a T-cell-poor microenvironment is associated with genomic amplification of the MYCN (N-MYC) proto-oncogene in primary metastatic neuroblastomas [68]. In SABCS2020, Lee JV, et al. reported MYC overexpression is loss of MHC class I in breast cancer, which is related to tumor immune.