Following Crk knockdown, integrin-dependent cell spreading and tyrosine phosphorylation of p130Cas, a downstream target following integrin engagement, are impaired, and both MDA-231 and SUM1315 cells with Crk knockdown have decreased ability to grow in soft agar and impaired tumor outgrowth associated with diminished proliferation in vivo. The gene discussed is BCAR1; the disease is neoplasm.