Compared with primary NSCLC specimens, an attenuated antigen presentation function of dendritic cells, reduced lymphocyte extravasation and down-regulated vascular cell adhesion molecule 1 (VCAM1) are examined in brain metastases, indicating that the immunosuppressive microenvironment is more pronounced in brain metastases than that of primary foci (51). The gene discussed is VCAM1; the disease is non-small cell lung carcinoma.