The expression levels of NGF, TrKA, PGP9.5 and the co‐localisation relationship among them were detected in BPH patients' prostate tissues, and results showed that NGF, TrKA and PGP9.5 were highly expressed in patients' prostates with moderate and severe prostate inflammation, and NGF, TrKA and PGP9.5 were also co‐localised in the prostates of BPH patients (Figure 7E). Here, NGF is linked to benign prostatic hyperplasia.