[51] Of interest, in a recent study of human breast cancer samples, four CAF subtypes were identified and the vascular (vCAF) and mesenchymal (mCAF) subtypes associated with developing metastatic disease.[28] In the TCGA dataset, both of those subtypes of CAF are significantly increased in the HR + HER2− breast tumors as compared to the TN breast tumors and there is higher significance in the immune-high population (Fig. 5A and B). This evidence concerns the gene ERBB2 and breast neoplasm.