FAP and neoplasm: Clusters 0, 2, 3, and 8 were mainly derived from tumor tissues and characterized by high expression of classical CAF markers (FAP, PDPN, and metalloproteinases) and extracellular matrix (ECM) signature proteins such as multi-collagen molecules and periostin (POSTN); therefore, we defined these clusters as mCAFs (Fig. 3a–c).