Gene expression profiling of lymph node metastasis by oligomicroarray analysis using laser microdissection in esophageal squamous cell carcinoma

We applied oligomicroarray analysis of 17086 genes to identify the genes related to lymph node metastasis in esophageal squamous cell carcinoma (ESCC). The samples of cancer and non-cancerous paired tissue were taken from 16 patients with ESCC who underwent esophagectomy with lymph node dissection. Total ribonucleic acid was extracted from the cancer cells obtained by using laser microdissection and was amplified by T7 based-amplification for the application to the oligomicroarray. The oligomicroarray demonstrated 43 overexpressed genes, such as cell-cycle regulators, cell adhesion related genes, anti-apoptosis related genes, and 138 suppressed genes such as cell differentiation related and apoptosis related genes in ESCC cells with lymph node metastasis. Among them, 5 overexpressed genes (SPP-1, CKS2, CCT5, STMN1, NDUFB9) and one suppressed expression gene (GJB2) were selected in the gene profiles, and then the expressions of those genes were confirmed by real-time semi-quantitative reverse transcriptional polymerase chain reaction (RT-PCR) method for confirmation of the result not only in study cases but also in additional 21 cases. The gene expression by real-time semi-quantitative RT-PCR was in accordance with the microarray data. Although we were able to extract some genes related to nodal metastasis in ESCC, further examination is necessary in other genes as well as the interaction of stromal tissues.