CD4 and lung cancer: To show that tumor-specific CD8+ and CD4+ T cell responses to tumor antigens expressed specifically in H522 and H520 lung cancer cell lines are present in NSCLC patients we analyzed the expression of MAGE-A3, MAGE-A4, hTERT, Survivin and Mucin-1, well-characterized antigens found in lung cancer tumors [27–29] by qPCR.