Coexpression of receptor-tyrosine-kinases in gastric adenocarcinoma--a rationale for a molecular targeting strategy?

Department of General and Abdominal Surgery, Johannes Gutenberg University of Mainz, Mainz, Germany.
World Journal of Gastroenterology (Impact Factor: 2.43). 08/2007; 13(26):3605-9.
Source: PubMed

ABSTRACT To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma.
The (co-)expression pattern of VEGFR1-3, PDGFR alpha/beta and EGFR1 was analyzed by RT-PCR in 51 human gastric adenocarcinomas. In addition, IHC staining was applied for confirmation of expression and analysis of RTK localisation.
The majority of samples revealed a VEGFR1 (98%), VEGFR2 (80%), VEGFR3 (67%), PDGFR alpha (82%) and PDGFR beta (82%) expression, whereas only 62% exhibited an EGFR1 expression. 78% of cancers expressed at least four out of six RTKs. While VEGFR1-3 and PDGFR alpha revealed a predominantly cytoplasmatic staining in tumor cells, accompanied by an additional nuclear staining for VEGFR3, EGFR1 was almost exclusively detected on the membrane of tumor cells. PDGFR beta was restricted to stromal pericytes, which also depicted a PDGFR alpha expression.
Our results reveal a high rate of receptor-tyrosine-kinases coexpression in gastric adenocarcinoma and might therefore encourage an application of multiple-target RTK-inhibitors within a combination therapy.


Available from: Annett Maderer, Mar 03, 2015
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