Increased NM23: MTS1 ratio inversely correlated with metastasis behaviour in human lung squamous cell carcinoma

The nm23 and mts1 genes have been the focus of attention as regards the association of their expression with metastatic behaviour. The level of nm23 and mts1 gene products has been demonstrated to correlate with metastatic potential in some tumors, but not in all. Here we show that these two genes might be coregulated and the ratio of their expression correlated with metastatic behaviour. Western blot analysis showed that the expression of both NM23 and MTS1 proteins was reduced in human lung cancer CH27 cells by retinoic acid treatment, but the ratio of NM23: MTS1 increased in a dose-dependent manner. Results also exhibited that retinoic acid altered the microtubule assembly of CH27 cells and reduced the metastatic ability of the cells in vitro. These data suggest that the metastatic potential of CH27 cells may be related to the relative expression of these two genes, and that their pathway in regulating metastatsis might be linked.