Secretion of biologically active recombinant human granulocyte-macrophage colony-stimulating factor by transduced gastric cancer cells.
OBJECTIVE
Gastric cancer has the highest incidence rate among cancers in Asia. The advanced type of signet ring cell carcinoma has poor prognosis compared to other types of gastric cancer. The immuno-gene therapy with cytokine-based tumor vaccines has not yet been investigated for gastric cancer. The granulocyte macrophage colony-stimulating factor (GM-CSF)-based tumor vaccine has been demonstrated as the most potent stimulator for specific and long-lasting systemic tumor immunity.


METHODS
In the present study, KATO III cells, the human signet ring cell gastric carcinoma cell line, were genetically modified by the transduction with the human GM-CSF cDNA or the modified hGM-CSF in replication-deficient retroviruses. The genomic integrations and mRNA expressions of the transgenes were determined by Southern and Northern blot analyses.


RESULTS
Wild type (wt) or modified hGM-CSF was integrated into the genome of KATO III cells. The modified hGM-CSF mRNA was more stable than that of wt. The KATO III cells with the modified hGM-CSF produced higher level of hGM-CSF (12.4-19 ng/10(6)cells/48hrs) than that with wt hGM-CSF, when determined by enzyme-linked immunosorbent assay (ELISA). The secreted recombinant hGM-CSF could support the proliferation of the GM-CSF-dependent cell line, indicating that the hGM-CSF secreted by the transduced KATO III cells has biological activities. Irradiated, transduced KATO III cells continued to secret hGM-CSF without proliferation.


CONCLUSIONS
Our results suggest that GM-CSF secreting KATO III cells could be tested for the treatment of gastric cancer as an allogeneic tumor vaccine as a part of immunotherapeutic treatment.
Kim
Hee-Young
HY
Department of Microbiology, Ajou University School of Medicine, 5 Woncheon-dong, Suwon 443-721, Korea.
Park
Gil-Soon
GS
Shin
Ho-Joon
HJ
Park
Sun
S
Kim
Kyongmin
K
Kim
Hyung-Il
HI
D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D045744:Cell Line, Tumor; D004797:Enzyme-Linked Immunosorbent Assay; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D016296:Mutagenesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014161:Transduction, Genetic
D012333:RNA, Messenger; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor