All five genes retained significant differential expression after removal of five breast cancer samples (HBCX10, HBCX11, HBCX24, HBCX6 and HBCX9) expressing CAF markers FAP/CSPG4 in the human component, addressing the possibility that persistent retention of patient stroma in the BTNBC PDX models was confounding results. The gene discussed is FAP; the disease is breast cancer.