RNA-seq tumor immunome analysis of murine breast cancer model EMT6-hHER2 responsive to novel antibody drug conjugate T-PNU

An orthotopic murine breast cancer model was created by transfecting the human HER2 gene into the breast cancer cell line EMT6 resulting in EMT6-hHER2. Previous in vivo tumor treatments with trastuzumab, trastuzumab-emtansine (T-DM1) and a novel antibody drug conjugate (ADC) T-PNU (provided by NBE therapeutics and carrying the highly potent anthracycline analogue PNU-159682) revealed that EMT6-hHER2 tumors are unresponsive to standard therapy treatments of trastuzumab and T-DM1, but respond well to the novel ADC T-PNU. Identifying immunogenic cell death properties of T-PNU, we postulated a therapeutic relevance for T-PNU mediated immune modulation of the tumor microenvironment. In order to identify the transcriptional pathways underlying the T-PNU anti-tumor response, we performed RNA-sequencing analysis of CD45+ tumor-derived cells from differently treated cohorts (untreated, trastuzumab, T-DM1, T-PNU; n=6). mRNA of CD45+ tumor-immune cells from differently treated murine cohorts were sequenced by Illumina NextSeq.