Related Experiment Video
Updated: Aug 13, 2026

Detection of Alternative Splicing During Epithelial-Mesenchymal Transition
Published on: October 9, 2014
An essential role of alternative splicing of c-myc suppressor FUSE-binding protein-interacting repressor in
Kazuyuki Matsushita1, Takeshi Tomonaga, Hideaki Shimada
1Departments of Frontier Surgery, Molecular Diagnosis, and Molecular Pathology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, Japan 160-8670.
Abstract:
Elevated expression of c-myc has been detected in a broad range of human cancers, indicating a key role for this oncogene in tumor development. Recently, an interaction between FUSE-binding protein-interacting repressor (FIR) and TFIIH/p89/XPB helicase was found to repress c-myc transcription and might be important for suppressing tumor formation. In this study, we showed that enforced expression of FIR induced apoptosis. Deletion of the NH(2)-terminal repression domain of FIR rescued the cells from apoptosis as did coexpression of c-Myc with FIR; thus, repression of Myc mediates FIR-driven apoptosis. Surprisingly, a splicing variant of FIR unable to repress c-myc or to drive apoptosis was frequently discovered in human primary colorectal cancers but not in the adjacent normal tissues. Coexpression of this splicing variant with repressor-competent FIR, either in HeLa cells or in the colon cancer cell line SW480, not only abrogated c-Myc suppression but also inhibited apoptosis. These results strongly suggest the expression of this splicing variant promotes tumor development by disabling FIR repression and sustaining high levels of c-Myc and opposing apoptosis in colorectal cancer.
Related Concept Videos
RNA Splicing
Abnormal Proliferation
Alternative RNA Splicing
There are five types of alternative RNA splicing that vary in the ways the pre-mRNA segments are removed or retained in the mature mRNA. The first...
Induced Pluripotent Stem Cells
Somatic cells are...
Master Transcription Regulators
Loss of Tumor Suppressor Gene Functions
When the tumor suppressor genes develop mutations or are lost, cells start growing out of control, leading to cancer. However, a single functional copy of the tumor suppressor gene is enough for the cells to maintain their normal functions and cell...

