IMPAIRED IN-VIVO TUMOR-GROWTH OF HUMAN PANCREATIC-CARCINOMA CELLS RETROVIRALLY TRANSDUCED WITH GM-CSF GENE

We have examined the antitumor effect of human pancreatic carcinoma ce lls (AsPC-1) retrovirally transduced with mouse granulocyte macrophage -colony stimulating factor (GM-CSF) gene in nude mice. Growth retardat ion of the subcutaneous tumors of GM-CSF-producing AsPC-1 cells was ob served, although their in vitro proliferation was not different fr om that of wild-type cells. Histological examination revealed infiltratio n of monocytic cells into the tumor of GM-CSF-producing cells, and the y were shown to be mainly, CD11b positive cells by immunohistochemical staining. The survival of the mice inoculated intraperitoneally with GM-CSF-producing AsPC-1 cells was significantly prolonged compared wit h that of the mice inoculated with wild-type AsPC-1 cells. Thus, the e xpression of GM-CSF gene in human pancreatic cells induced an antitumo r effect in vivo even in the mature T cell-deficient condition.