Gene expression profiling in sinonasal adenocarcinoma.

Transcriptional profiling of ethmoïd tumors samples comparing normal samples from the controlateral sinus. RNA were extracted from biopsies. Sinonasal adenocarcinomas are uncommon tumors developping in ethmoid sinus after wood dust exposure. Although the etiology of these tumors is well defined very little is known regarding the molecular basis of these tumors. In an attempt to identify genes involved in this disease we proceed to a gene expression profiling using cancer-dedicated microarrays, on matched samples of nine sinonasal adenocarcinomas and non-tumoral sinusal tissue. Among the genes with significant differential expression we selected: LGALS4, ACS5, CLU, BAX, PDGFRa, SRI and CCT5 for further exploration by quantitative real-time reverse-transcription-PCR on a larger set of tumors and confirmed the microarray data. Protein expression alterations were shown for LGALS4, ACS5, and CLU by immunohistochemistry. Our results suggest that two genes might be involved in the pathogenesis of these tumors: LGALS4 highly up-regulated, particularly in the most differentiated tumors, and CLU, whose expression was lost. After further evaluation these genes could be used as markers for a better characterization of these tumors and will potentially help to an earlier detection of cancer in woodworkers, who have high risk of developing sinonasal adenocarcinomas. Two-condition experiment tumor samples from frozen section vs normal samples. There were two arrays by sample when it was possible.