Transgenic C57BL/6 p14 mice harbor a TCR directed against the lymphocytic choriomeningitis virus (LCMV) antigen gp33–41 (gp33) presented in the context of H2-Kb.29 When E1A-MEF and E1A-Cox2-MEF were loaded with the gp33 peptide and incubated with p14 splenocytes, COX-2 expression again mediated significantly increased clonogenic survival of cancer cells (Figure 4a). This evidence concerns the gene PTGS2 and cancer.