The FHIT gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumor suppressor gene involved in multiple tumors, including esophageal carcinoma. We analyzed Fhit expression using an immunohistochemical method in invasive carcinoma, carcinoma in situ (CIS) and dysplasia, in paraffin sections of 75 esophageal squamous cell carcinomas (ESCs) to further elucidate the role of Fhit protein in esophageal carcinogenesis. In addition, we also examined whether Fhit expression correlated with p53 expression and apoptosis. Compared to adjacent normal mucosa, significant loss or reduction of Fhit expression was noted in 67 of 75 (89.3%) invasive ESCs, in 13 of 19 (68.4%) CIS lesions, and in 10 of 23 (43.5%) dysplastic lesions. There was a progressive loss or reduction of Fhit expression with progressive increases in the severity of histopathological changes (p < 0.001). However, there was no association between Fhit expression and clinicopathological findings, including tumor stage, lymph node metastasis, or overall survival. Moreover, Fhit expression was not significantly associated with p53 expression and apoptosis. These results indicate that abnormal Fhit expression is a common event in the early stage of ESC development and may occur independently of p53 expression and apoptosis mechanisms.

The Fragile Histidine Triad gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumour suppressor gene involved in multiple tumour types including colorectal carcinomas. Recently, it has been reported that the Fragile Histidine Triad gene may be a target of damage in a fraction of mismatch deficient tumours. To explore this hypothesis, we analysed both Fragile histidine triad and mismatch repair protein (Msh2 and Mlh1) expression using immumohistochemical methods in 52 advanced colorectal carcinomas (19 well-, 17 moderately-, and 16 poorly-differentiated). In addition, we examined whether the Fragile histidine triad and mismatch repair protein expression correlated with p53 expression and clinicopathological findings. Significant loss or reduction of Fragile histidine triad expression was noted in 18 of the 52 (34.6%) advanced colorectal carcinomas: 2 (10.5%) well-differentiated, 3 (17.6%) moderately-differentiated, 13 (81.3%) poorly-differentiated carcinomas, the frequency being significantly higher in the latter than that in the former two (P50.0001). Loss of mismatch repair protein (mainly, Mlh1) expression was detected in 21 of the 52 (40.4%) colorectal carcinomas. Moreover, reduced Fragile histidine triad expression was significantly associated with absence of mismatch repair protein expression in the advanced colorectal carcinomas (P50.0001). However, the Fragile histidine triad and mismatch repair protein expression was not significantly associated with p53 expression. These results suggested that reduced Fragile histidine triad expression might be correlated with mismatch repair expression, but not with p53 expression.

There is limited information on the molecular changes involved in the pathogenesis of gallbladder carcinoma (GBC). The Fragile Histidine Triad (FHIT) gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumor suppressor gene in a variety of human malignancies. Recent studies have suggested that Fhit inactivation can be a consequence of defects in mismatch repair proteins. We analyzed Fhit and Mlh1 protein expressions using immunohistochemical methods in 20 GBCs and three gallbladder adenomas (GBAs) to elucidate the role of Fhit protein in gallbladder carcinogenesis. In addition, we examined whether Fhit and Mlh1 protein expressions correlated with P53 expression and clinicopathological findings. Significant loss or reduction in Fhit expression was noted in nine (45%) of the GBCs and one of the GBAs. Loss of Mlh1 protein expression was detected in six (30%) of the GBCs and one of the GBAs. Reduced Fhit expression was significantly associated with the absence of Mlh1 protein expression in the GBCs and the GBAs (p=0.0186). P53 overexpression was present in 11 (55%) of the GBCs, but none of the GBAs. Fhit and Mlh1 protein expressions were not significantly associated with P53 expression and clinicopathological findings. These results suggested that reduced Fhit expression might be involved in the development of GBC and be correlated with Mlh1 expression.

The fragile histidine triad (FHIT) gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumour suppressor gene involved in a variety of tumours, including gastric carcinomas. Recently, it has been reported that the FHIT gene may be a target of damage in some of mismatch-deficient tumours. To clarify further the role of the Fhit protein in gastric carcinogenesis, we investigated whether Fhit expression in early gastric neoplasia is associated with mismatch repair protein expression and cellular phenotype. Fhit, Mlh1 and phenotypic expression were evaluated immunohistochemically in 87 early gastric neoplasias, comprising 32 adenomas and 55 intramucosal carcinomas, resected by endoscopic mucosal resection therapy. Significant loss or reduction of Fhit expression was noted in four (12.5%) of the 32 adenomas and 21 (38.2%) of the 55 intramucosal carcinomas. The rate of abnormal Fhit expression was significantly higher in intramucosal carcinomas than in adenomas (P ¼ 0.021). Moreover, reduced Fhit expression was found to be significantly associated with loss of Mlh1 expression in early gastric neoplasia (P ¼ 0.0011). Furthermore, we also detected a significant association between reduced Fhit expression and gastric phenotype (P ¼ 0.0018). These results suggested that reduced Fhit expression occurs in the early stage of gastric carcinogenesis and could be correlated with a lack of Mlh1 expression and gastric phenotype.

A case which presented with early cancer of the duodenal duplication in addition to a gallbladder defect is reported. This may be the first case of its kind reported in the literature.