Among them, POSTN, which encodes periostin (a protein secreted by cancer-associated fibroblasts (CAFs) and promotes the formation of cancer stem cell, perivascular and premetastatic niches43), was substantially upregulated in TRCs and PCs and in SMC subclusters of FL (Fig. 5c, Extended Data Fig. 7b and Supplementary Table 17). This evidence concerns the gene POSTN and cancer.