In a concurrent study of six CAF markers, viz., α-SMA, FAP, FSP-1, CD29, PDGFR-β, and CAV-1 (caveolin-1), four distinct CAF subpopulations, viz., CAF-S1, S2, S3, and S4, were found in human breast and ovarian cancers with distinct expression profiles (Figure 2) [64,65]. The gene discussed is CAV1; the disease is ovarian carcinoma.