Antitumor response of genetically engineered IL-2 expression to human esophageal carcinoma cells in mature T cell-defective condition.
We examined whether antitumor effect could be produced by retrovirally expressed human interleukin-2 (hIL-2) gene in human esophageal cancer cells (T.Tn) using immunocompromised nude mice. Loss of tumorigenicity of hIL-2-producing T.Tn (T.Tn/hIL-2) cells inoculated subcutaneously was observed in contrast to continuous tumor growth of wild-type cells, although in vitro proliferation of T.Tn/hIL-2 cells remained the same as that of wild-type cells. The antitumor effect was also evidenced by the injection of T.Tn/hIL-2 cells into established tumors of wild-type cells. The injection significantly retarded the subsequent growth of wild-type tumors. Histological examination of regressing T.Tn/hIL-2 cells revealed necrotic areas and infiltration of several types of inflammatory cells. Treatment of nude mice with anti-asialoGM1 antibody did not influence the IL-2-mediated tumor rejection. Vaccination of nude mice with irradiated T.Tn/hIL-2 cells whose secretion of hIL-2 in amount was comparable to that of unirradiated cells did not develop protective immunity. Taken together, the antitumor effect achieved in nude mice by the inoculation of T.Tn/hIL-2 cells is mediated by non-T non-natural killer cells.
Matsubara
H
H
Department of Surgery (II) School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan.
Koide
Y
Y
Sugaya
M
M
Gunji
Y
Y
Asano
T
T
Ochiai
T
T
Takegana
K
K
Sakiyama
S
S
Tagawa
M
M
D000818:Animals; D004938:Esophageal Neoplasms / Q000235:genetics / Q000276:immunology / Q000628:therapy*; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D006801:Humans; D007376:Interleukin-2 / Q000235:genetics* / Q000627:therapeutic use; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured
D007376:Interleukin-2