Supplementary Table S1 gives an overview of patients from whom CAF were derived. Microseminoprotein (MSMB) beta is a protein expressed in normal and BPH prostate but is decreased or absent in PCa [23], and we stained patient samples for MSMB to confirm the presence of tumour in the tissue specimens. While BPH control tissue showed strong MSMB staining, this was low or absent in PCa specimens, as shown in Figure 1A. This evidence concerns the gene MSMB and benign prostatic hyperplasia.