Pyk2 plays an important role in cell motility and invasion [21, 22, 23, 24, 25], and Pyk2 expression is shown to occur frequently in human astrocytomas with a significant correlation between the grade of malignancy of astrocytomas and the expression of Pyk2 [26]. The gene discussed is PTK2B; the disease is astrocytoma (excluding glioblastoma).