A preparation of autologous cytotoxic T-lymphocytes (CTL), specifically reactive to the tumor-associated antigen (TAA) mucin-1 (MUC1), with potential antineoplastic activity. Peripheral blood mononuclear cells (PBMCs) are collected from the patient with MUC1-positive tumors and are exposed ex vivo to dendritic cells (DCs) transfected with a replication-deficient adenovirus encoding MUC1 to generate MUC1-specific CTLs, which are subsequently expanded in vitro. Upon re-infusion of autologous CTLs induced with MUC1 gene-transfected DCs to the patient, the CTLs target and lyse the MUC1-expressing tumor cells. This inhibits tumor cell proliferation. MUC1 is expressed by a variety of tumor cell types.