Abstract
The growth factor receptor oncogene, c-erb B-2, is frequently overexpressed in the adenocarcinomas of breast, ovary, lung and stomach. Although the mechanism of erb B-2 overexpression is thought as the result of transcriptional upregulation in many primary human carcinomas, expression rate of c-erb B-2 at mRNA level is usually lower than the level of translated protein. We also found that the expression of erb B-2 in SNU-1 stomach cancer cells was greater at post-transcription level (Bae et al., 1993). To explore the underlying mechanism of erb B-2 protein overexpression, we have chosen two cells lines, SNU-1 and SNU-16 where transcription rate of erb B-2 was closely resemble to each other while expressed protein levels were quite different. The synthesis rate of erb B-2 protein in SNU-1 cells was faster than SNU-16 cells while levels of erb B-2 mRNA were found to be similar in both cell lines. The half-life of the expressed erb B-2 protein was not significantly different in both cell lines. Analysis of the 5' untranslated region (UTR) of erb B-2 mRNA (-1approximately-323) showed no sequence abnormality in both cell lines. However, ribonuclease protection assay using cloned 5 UTR sequence revealed that the size of 5' UTR of erb B-2 mRNA which associate with transcription initiation site(s) in SNU-1 cells was longer than that in SNU-16. These results suggest that the increased erb B-2 protein synthesis rate possibly due to the redundant selection of transcription initiation might be a mechanism of erb B-2 overexpression in SNU-1 cells.
Similar content being viewed by others
Article PDF
Author information
Authors and Affiliations
Rights and permissions
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
About this article
Cite this article
Bae, C., Juhnn, Y. & Park, J. Post-transcriptional control of c-erb B-2 overexpression in stomach cancer cells. Exp Mol Med 33, 15–19 (2001). https://doi.org/10.1038/emm.2001.3
Published:
Issue Date:
DOI: https://doi.org/10.1038/emm.2001.3
Keywords
This article is cited by
-
MiR-16 mediates trastuzumab and lapatinib response in ErbB-2-positive breast and gastric cancer via its novel targets CCNJ and FUBP1
Oncogene (2016)
-
Prognosis significance of HER-2/neu overexpression/amplification in Chinese patients with curatively resected gastric cancer after the ToGA clinical trial
World Journal of Surgical Oncology (2012)
-
HER2/neu overexpression in the development of muscle-invasive transitional cell carcinoma of the bladder
British Journal of Cancer (2003)