Regulators affecting the metastasis suppressor activity of Nm23-H1.

Nm23-H1 encodes nucleoside diphosphate kinase A (NDPK-A) and is known to have a metastasis suppressive activity in many tumor cells. However, it has many other functions as well. Recent studies have shown that the interacting proteins with Nm23-H1 which mediate the cell proliferation, may act as modulators of the metastasis suppressor activity. The interacting proteins with Nm23-H1 can be classified into 3 groups. The first group of proteins can be classified as upstream kinases of Nm23-H1 such as CKI and Aurora-A/STK15. The second group of proteins acts as downstream effectors for the regulation of specific gene transcriptions, GTP-binding protein functions, and signal transduction in Erk signal cascade. The third group of proteins can be classified as bi-directionally influencing binding partners of Nm23-H1. As a result, the interactions with Nm23-H1 and binding partners have implications in the biochemical characterization involved in metastasis and tumorigenesis.