Expression of KISS1 and KISS1R (GPR54) may be used as favorable prognostic markers for patients with non-small cell lung cancer.

Lung cancer is the most commonly diagnosed cancer worldwide. Loss of KISS1 expression has been associated with progression and poor prognosis of various cancers, however, the precise role of KISS1 expression in non-small cell lung cancer (NSCLC) is not well defined. KISS1 receptor (KISS1R, also named GPR54) coupled to KISS1, has been shown to play a pivotal role in suppressing cancer metastasis. In this study, 56 NSCLC specimens were divided into stage IIIB (locally advanced) and stage IV (metastatic). The mRNA and protein levels of KISS1 and KISS1R in cancer tissues were found to be lower compared to that in normal tissues using RT-PCR and western blot analysis, respectively. In addition, the expression of both KISS1 and KISS1R in stage IV NSCLC was lower compared to that in stage IIIB stage NSCLC. The cumulative survival rate of the patients with KISS1 or KISS1R expression was significantly higher compared to that without expression. KISS1 or KISS1R expression in NSCLC can be used to indicate favorable prognosis for disease outcome. Metastin, the product of the KISS1 gene, was lower in the serum of patients with stage IV NSCLC compared to that in stage IIIB NSCLC.