Tissue-specific expression profiling of receptor for advanced glycation end products and its soluble forms in esophageal and lung cancer.

The receptor for advanced glycation end products (RAGE) interacts with several ligands and is involved in various human diseases. Several splicing forms of the RAGE gene have been characterized, and two general mechanisms are usually responsible for the generation of soluble receptors. However, variants distribution and respective roles in different tumors are not clear. We analyzed RAGE and hRAGEsec mRNA expression in esophageal and lung cancer by RT-polymerase chain reaction. The Agilent clipper 1000 Bioanalyzer using lab-on-a-chip technology was applied to size and quantify the polymerase chain reaction products. Western blotting was performed to measure total soluble RAGE protein levels. The results showed that RAGE and its splice variants increased in esophageal cancers and decreased in lung cancers. We conclude that RAGE presents as a major isoform; soluble RAGE may also play certain roles in esophageal cancer and lung cancer.