Title

Proximal promoter sequences mediate cell-specific and elevated expression of the favorable prognosis marker TrkA in human neuroblastoma cells

UMMS Affiliation

Department of Physiology

Date

1-2-1998

Document Type

Article

Subjects

Humans; Neuroblastoma; *Promoter Regions (Genetics); Receptor, trkA; Regulatory Sequences, Nucleic Acid; Transcription, Genetic; Tumor Cells, Cultured

Disciplines

Biochemistry, Biophysics, and Structural Biology | Cell and Developmental Biology

Abstract

The nerve growth factor receptor, TrkA, has a critical role in the survival, differentiation, and function of neurons in the peripheral and central nervous systems. Recent studies have demonstrated a strong correlation between abundant expression of TrkA and a favorable prognosis of the pediatric tumor, neuroblastoma. This correlation suggests that TrkA may actively promote growth arrest and differentiation of neuroblastoma tumor cells and may be an important therapeutic target in the treatment of this disease. In the present study, we have examined the mechanistic basis for TrkA gene expression in human neuroblastoma cells. Northern blotting and nuclear run-on analyses demonstrated that transcription is a primary determinant of both cell-specific and variable expression of the TrkA gene in neuroblastoma cell lines that express it to different degrees. Cell-specific and variable transcription in neuroblastoma cells was recapitulated by transient transfection of TrkA promoter-luciferase reporter constructs, and regulatory sequences mediating these processes were localized to a 138-base pair region lying just upstream of the transcription initiation region. This neuroblastoma regulatory region formed multiple DNA-protein complexes in gel shift assays that were highly enriched in neuroblastoma cells exhibiting abundant TrkA expression. Thus, TrkA-positive neuroblastoma cells are distinguished by differential expression of putative transcription factors that ultimately may serve as targets for up-regulating TrkA expression in tumors with poor prognosis.

Rights and Permissions

Citation: J Biol Chem. 1998 Jan 2;273(1):39-44.

Related Resources

Link to Article in PubMed

Journal Title

The Journal of biological chemistry

PubMed ID

9417044