Transcriptional inhibition of type I collagen gene expression in scleroderma fibroblasts by the antineoplastic drug ecteinascidin 743.

Abstract

We previously showed that COL1A1 expression is up-regulated at the transcriptional level in systemic sclerosis (SSc) fibroblasts and that the CCAAT-binding factor (CBF) is involved in this increased expression. Ecteinascidin 743 (ET-743) is a chemotherapeutic agent that binds with sequence specificity to the minor groove of DNA and inhibits CBF-mediated transcriptional activation of numerous genes. Therefore, we examined the effects of ET-743 on the increased COL1A1 expression in SSc fibroblasts. The drug caused a potent and dose-dependent inhibition of type I collagen biosynthesis, which reached 70-90% at 700 pM without affecting cell viability. The same drug concentration caused 60-80% reduction in COL1A1 mRNA levels. The stability of the corresponding transcripts was not affected. In vitro nuclear transcription assays demonstrated a 54% down-regulation of COL1A1 transcription. Transient transfections with COL1A1 promoter constructs containing the specific CBF binding sequence into SSc cells previously treated with 700 pM ET-743 failed to show an effect on COL1A1 promoter activity. Furthermore, ET-743 did not affect the binding of CBF or Sp1 transcription factors to their cognate COL1A1 elements. However, treatment with 700 pM ET-743 of stably transfected NIH 3T3 cells expressing a human type II procollagen gene under the control of the human COL1A1 promoter caused a greater than 50% reduction in the production of type II procollagen and a similar decrease in the corresponding type II procollagen transcripts. These results indicate that ET-743 is a potent inhibitor of COL1A1 transcription. However, this effect cannot be explained by a direct effect on CBF binding to the COL1A1 promoter. Although the exact mechanisms responsible for the transcriptional inhibition of COL1A1 by ET-743 are not apparent, our observations suggest that the drug may be an effective agent to decrease collagen overproduction in SSc and other fibrotic diseases.

• Authors: Natalia Louneva, Biagio Saitta, David J Herrick, Sergio A Jimenez
• Journal: The Journal of biological chemistry (J Biol Chem) Vol. 278 Issue 41 Pg. 40400-7 (Oct 10 2003) ISSN: 0021-9258 [Print] United States
• PMID: 12881530 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Antineoplastic Agents, Alkylating
• Collagen Type I
• Collagen Type I, alpha 1 Chain
• Collagen Type II
• Dioxoles
• Isoquinolines
• RNA, Messenger
• Tetrahydroisoquinolines
• DNA
• Trabectedin

Topics

• 3T3 Cells
• Animals
• Antineoplastic Agents, Alkylating (pharmacology)
• Base Sequence
• Cell Line
• Collagen Type I (genetics)
• Collagen Type I, alpha 1 Chain
• Collagen Type II (genetics)
• DNA (genetics)
• Dioxoles (pharmacology)
• Fibroblasts (drug effects, metabolism)
• Gene Expression (drug effects)
• Humans
• Isoquinolines (pharmacology)
• Mice
• Promoter Regions, Genetic
• RNA, Messenger (genetics, metabolism)
• Scleroderma, Diffuse (drug therapy, genetics)
• Tetrahydroisoquinolines
• Trabectedin
• Transfection