Modulation of c-fms proto-oncogene in an ovarian carcinoma cell line by a hammerhead ribozyme.

Abstract

Co-expression of macrophage colony-stimulating factor (M-CSF) and its receptor (c-fms) is often found in ovarian epithelial carcinoma, suggesting the existence of autocrine regulation of cell growth by M-CSF. To block this autocrine loop, we have developed hammerhead ribozymes against c-fms mRNA. As target sites of the ribozyme, we chose the GUC sequence in codon 18 and codon 27 of c-fms mRNA. Two kinds of ribozymes were able to cleave an artificial c-fms RNA substrate in a cell-free system, although the ribozyme against codon 18 was much more efficient than that against codon 27. We next constructed an expression vector carrying a ribozyme sequence that targeted the GUC sequence in codon 18 of c-fms mRNA. It was introduced into TYK-nu cells that expressed M-CSF and its receptor. Its transfectant showed a reduced growth potential. The expression levels of c-fms protein and mRNA in the transfectant were clearly decreased with the expression of ribozyme RNA compared with that of an untransfected control or a transfectant with the vector without the ribozyme sequence. These results suggest that the ribozyme against GUC in codon 18 of c-fms mRNA is a promising tool for blocking the autocrine loop of M-CSF in ovarian epithelial carcinoma.

• Authors: Y Yokoyama, S Morishita, Y Takahashi, M Hashimoto, T Tamaya
• Journal: British journal of cancer (Br J Cancer) Vol. 76 Issue 8 Pg. 977-82 ( 1997) ISSN: 0007-0920 [Print] England
• PMID: 9376277 (Publication Type: Journal Article)

Chemical References

• MAS1 protein, human
• Oncogene Protein gp140(v-fms)
• Proto-Oncogene Mas
• RNA, Catalytic
• RNA, Messenger
• Macrophage Colony-Stimulating Factor

Topics

• Base Sequence
• Binding Sites
• Carcinoma (genetics, metabolism)
• Cell Division (physiology)
• Choriocarcinoma (genetics, metabolism)
• Female
• Gene Expression Regulation, Neoplastic
• Genes, fms
• Humans
• Macrophage Colony-Stimulating Factor (biosynthesis, genetics)
• Molecular Sequence Data
• Nucleic Acid Conformation
• Oncogene Protein gp140(v-fms) (biosynthesis, genetics)
• Ovarian Neoplasms (genetics, metabolism)
• Proto-Oncogene Mas
• RNA, Catalytic (metabolism)
• RNA, Messenger (genetics, metabolism)
• Transfection
• Tumor Cells, Cultured