Human esophageal cancer cell lines and human esophageal cancer tissues were profiled on cDNA microarrays. In esophageal cancer cell lines, KYAE and OE-33 (adenocarcinomas) were distinguished from KYSE series (squamous cell carcinomas). Although SK-GT-4 and TE7 were derived from adenocarcinomas, they had a comparatively similar expression profile to the KYSE series. A set of genes whose expression commonly either increased or decreased in cancer cell lines was identified. Genes that were characteristically expressed in KYAE and OE-33 were also identified. The gene expression profiles of cancer tissues (CTs) were remarkably different from those of the cancer cell lines (CCLs). Notable differences between CCLs and CTs were observed in matrix metalloproteinases, plasminogen activator, collagens, paxillin, and thrombospondin 2, etc., whose expression was not increased in CCLs but increased in CTs. Twenty-three genes were extracted to categorize patients according to their prognoses, and clustering analyses, using these genes, were performed successfully.

No abstract

The fragile histidine triad (FHIT) gene has been proposed to have an important role in very early carcinogenesis. Methylation of the FHIT gene is associated with transcriptional inactivation in esophageal squamous cell carcinoma, and FHIT inactivation has been linked to smoking-related carcinogenesis. In this study, we confirmed methylation of the FHIT gene in human esophageal squamous epithelial cells (HEECs) and examined whether nicotine induced alteration of FHIT. Methylation status in the promoter region of the FHIT gene and p16 INK4A gene was determined by methylation-specific PCR in HEECs exposed to nicotine under various conditions. Methylation status of the FHIT gene was confirmed by DNA-sequencing analysis. The development of human cancer is generally considered a multistep process involving multiple genetic or epigenetic changes. Epigenetic changes such as aberrant DNA methylation are an alternative way to inactivate tumor suppressor genes (TSGs) and may have important roles in the development of esophageal cancer 1,2 DNA methylation patterns are established and maintained by 3 DNA methyltransferases (DNMTs): DNMT1, DNMT3a and DNMT3b. 3,4 DNMT1 has traditionally been regarded as a maintenance methyltransferase that specifically copies DNA methylation patterns after DNA replication. 5 In contrast, DNMT3a and DNMT3b are implicated primarily in de novo methylation. 6,7 Recent studies have localized the fragile histidine triad (FHIT) gene at 3p14.2, 8 considered a candidate TSG. FHIT is inactivated during the development of precancerous lesions of various types. 9,10 We have previously confirmed promoter methylation of the TSG p16 11 and FHIT 12 in esophageal squamous cell carcinoma (ESCC) cell lines established at our department. 13 Pekarsky et al. suggested that FHIT inactivation occurs very early in the development of carcinogen-induced tumors. Carcinogens from cigarette smoke and other sources cause deletions in the FHIT locus, leading to the loss of Fhit protein expression. Then, cells lacking FHIT expression presumably acquire growth advantages, proliferate, alter p16, p53, or other genes, and form precancerous lesions. 14 Therefore, inactivation of FHIT may be a downstream effect of defects in DNA repair machinery. Such inactivation may be a very early event in carcinogenesis, even preceding alteration of p16 INK4A . 14,15 The etiology of ESCC is strongly linked to the inactivation of FHIT or p16, as well as to cigarette smoking. 16,17 Considerable information on molecular abnormalities potentially related to cigarette smoking is now available. For example, FHIT gene abnormalities have been associated with a history of smoking in patients with malignant tumors, 18 and tobacco smoking has been linked to promoter methylation in p16 10 or FHIT. 14 Nicotine is the major addictive agent in tobacco, 19 and addicted individuals continue to smoke and use tobacco products to maintain plasma nicotine levels. Although studied extensively, nicotine has not been proven to be carcinogenic. However, researchers ha...

Nerve growth factor (NGF) is overexpressed not only in nervous system, but also in several types of cancers. However, the role of NGF in oesophageal squamous cell carcinoma (OESCC) remains unclear. Here, we show the first evidence of NGF-TrkA autocrine loop and clinical significance of NGF overexpression in OESCC. Immunohistochemical study of 109 OESCC specimens revealed that NGF overexpression, found in 63 out of 109 patients (57.8%), was associated with lymph node metastasis, distant metastasis, higher TNM stage, poorer tumour differentiation, and poorer survival. NGF overexpression was also associated with strong expression of TrkA and negative expression of low-affinity neurotrophin receptor (p75NTR). Semiquantitative reverse transcription -polymerase chain reaction (RT -PCR) of 19 surgical specimens showed upregulation of NGF mRNA in 17 out of 19 (89%) patients. All five OESCC cell lines tested in vitro secreted detectable NGF in enzyme-linked immunosorbent assay, and expressed TrkA and p75NTR on RT -PCR and Western blot. The motility of HSA/c, one of the OESCC cell lines overexpressing NGF, was significantly decreased by either neutralising anti-NGF antibody, an inhibitor of TrkA, or NGF-small interfering RNA in transwell migration assay. Our findings suggest that NGF is of potential interest not only as a prognostic factor, but also as a novel therapeutic target in OESCC.

RT-PCR for SCCA mRNA can detect oesophageal cancer cells in peripheral blood. The presence of such cells in blood samples obtained on admission or during operation is a useful predictor of outcome in patients with oesophageal squamous cell carcinoma.