A method of preparing autologus T-lymphocytes for re-introduction into a patient having 
cancer, which method comprises obtaining 
peripheral blood mononuclear cells (PBMCs) from a patient immunized with an 
antigen of the 
cancer, stimulating the PBMCs with the 
antigen of the 
cancer in vitro, transducing the PBMCs with a retrovial vector, which (a) comprises and expresses a human 
interleukin-2 (IL-2) coding sequence operably linked to a retroviral 
promoter, (b) does not comprise an exogenously introduced 
gene that enables phenotypic selection, and (c) comprises a 
viral envelope that efficiently transduces CD8+ T-lymphocytes; a method of preparing 
autologous tumor-infiltrating lymphocytes (TILs) for reintroduction into a patient having cancer, which method comprises obtaining TILs from a tumor of the patient, optionally immunized with an 
antigen of the cancer, optionally stimulating the TILs with the antigen of the cancer 
in vitro, and transducing the TILs with the aforementioned retroviral vector, compositions comprising cells obtained in accordance with such methods; and methods of treating a patient having cancer by administering to the patient cells obtained in accordance with such methods or compositions comprising same.