The study looked at two genes, Kiss-1 and KAI-1, that can help stop cancer from spreading. In stomach cancer samples, both genes were found at lower levels than in nearby healthy tissue, and the lower the levels, the more advanced the cancer was. The two genes tended to be expressed together.

To investigate the mRNA levels of Kiss-1 and KAI-1 metastasis suppressor genes in gastric cancer, and to explore its clinical value. In situ hybridization was used on routinely paraffin-embedded sections of resected specimens of 49 cases with gastric cancer and 20 cases with pericancerous tissue. The positive rates and the scores of Kiss-1 and KAI-1 mRNA in gastric cancer tissue were significantly lower than those in pericancerous tissue (P<0.01). The positive rates and scores in normal to mild-atypical hyperplasia cases were significantly higher than those in middle to severe-atypical hyperplasia of pericancerous tissue (P<0.05,P<0.01). The positive rates and scores of Kiss-1 and KAI-1 mRNA in patients with infiltrating depth T1~T2, without lymph node metastasis, with only first group of lymph node metastasis, and without distant organ metastasis were significantly higher than those in patients with infiltrating depth T3~T4, with lymph node metastasis, with second or third group of lymph node metastasis and with distant organ metastasis. A strong positive correlation was found between the expressive scores of Kiss-1 and KAI-1 mRNA in gastric cancer (r=0.53, P<0.01). The expression of Kiss-1 and/or KAI-1 mRNA may be important biological markers of reflecting invasive and metastatic potential and prognosis in gastric cancer. The assays of Kiss-1 and/or KAI-1 mRNA expression level in benign lesions of stomach may have important clinical value for the protection and early-stage finding of gastric cancer.