Researchers found that prostate cancer cells can release a molecule called kisspeptin in the lab, and the gene for kisspeptin is present in normal prostate tissue, but people with prostate cancer don’t have higher kisspeptin levels in their blood, so it isn’t a useful blood test or supplement right now.

Kisspeptin, the product of the KiSS-1 gene, inhibits metastasis and stimulates the hypothalamo-pituitary-gonadal axis. Kisspeptin is therefore a putative target in the treatment of hormone-sensitive malignancies. Prostatic carcinoma remains a significant cause of mortality despite improvements in therapy. The role of kisspeptin in prostatic carcinoma remains undefined. We therefore aimed to investigate release of kisspeptin by prostatic cancer cell lines; investigate expression of KiSS-1 in human prostate tissue; investigate whether patients with prostate carcinoma have elevated plasma kisspeptin. 1) Culture medium from prostatic carcinoma cell lines LNCaP, DU145 and PC3 was assayed for kisspeptin immunoreactivity (-IR). Kisspeptin-IR release was detectable from all three cell lines. The effect of hydroxyflutamide, gefitinib and resveratrol on kisspeptin-IR release from these cell lines was also investigated. No effect of the drugs tested on release of kisspeptin-IR was observed. 2) Expression of KiSS-1 in human prostate tissue (n=4) was investigated using in situ hybridisation. Expression of KiSS-1 was detected in human prostate tissue. 3) Plasma kisspeptin-IR was compared in 92 patients with prostatic carcinoma and 73 male controls. Kisspeptin-IR was not detected in the plasma of either patients with prostate cancer or control patients. We have therefore shown for the first time the release of kisspeptin-IR by prostatic carcinoma cell lines. We have also shown that KiSS-1 is expressed in human prostate tissue, and that circulating levels of kisspeptin-IR are not elevated in patients with prostatic carcinoma. Further work is required to determine the role of kisspeptin in the prostate.