The major findings of this report are as follows: (1) the C-terminal CNH domain of the Ste20 homolog MAP4K4 was identified as a binding partner for the Pyk2 FERM domain, (2) the MAP4K4 CNH domain and full length MAP4K4 coimmunoprecipitated with Pyk2 from cell lysates, (3) knockdown of MAP4K4 expression inhibited glioma cell migration and blocked Pyk2 stimulation of migration, (4) increased expression of MAP4K4 stimulated glioma cell migration, (5) MAP4K4 stimulation of glioma cell migration was blocked by knockdown of Pyk2 expression. This evidence concerns the gene PTK2B and central nervous system cancer.