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BACKGROUND: Evaluation of the biological character of carcinomas requires understanding of cell cycle regulators. P57 (Kip2) belongs to the Cip/Kip family and is known to be one of the universal negative regulators of cell cycle. METHODS: In the present study, therefore, we investigated p57 expression in 37 extrahepatic bile duct carcinomas (BDC) and 28 intrahepatic cholangiocellular carcinomas (CCC). RESULTS: The average p57 labeling index (LI) in BDC and CCC were 60.8 +/- 7.9 and 58.6 +/- 18.6, respectively, which were significantly lower (p = 0.0008 and p = 0.0408, respectively) than those in normal duct epithelia (73.1 +/- 7.9, 70.4 +/- 8.2). p57 LI was significantly lower in BDC and CCC cases with biological aggressive phenotypes such as poor differentiation (p = 0.0260 and p = 0.0069), lymph node metastasis (p = 0.0274 and p = 0.0214), high Ki-67 LI (p = 0.0164 and p = 0.0343) and cyclin D1 overexpression (p = 0.0359 and p = 0.0255). CONCLUSION: These findings suggest that decreased p57 expression is related to the increased activity of cell proliferation and also the progression of these carcinomas.  相似文献   
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BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) usually develops following chronic liver inflammation caused by hepatitis C or B virus. Through expression profiling in a rare type of HCC, for which the causes are unknown, we sought to find key genes responsible for each step of hepatocarcinogenesis in the absence of viral influence. METHODS: We used 68 non-B, non-C liver tissues (20 HCC, 17 non-tumor, 31 normal liver) for expression profiling with PCR-array carrying 3072 genes known to be expressed in liver tissues. To select the differentially expressed genes, we performed random permutation testing. A weighted voting classification algorithm was used to confirm the reliability of gene selection. We then compared these genes with the results of previous expression profiling studies. RESULTS: A total of 220 differentially expressed genes were selected by random permutation tests. The classification accuracies using these genes were 91.8, 92.0 and 100.0% by a leave-one-out cross-validation, an additional PCR-array dataset and a Stanford DNA microarray dataset, respectively. By comparing our results with previous reports on virus-infected HCC, four genes (ALB, A2M, ECHS1 and IGFBP3) were commonly selected in some studies. CONCLUSIONS: The 220 differentially expressed genes selected by PCR-array are potentially responsible for hepatocarcinogenesis in the absence of viral influence.  相似文献   
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Background

Neoadjuvant chemotherapy (NACT) improves the prognosis of patients with esophageal cancer who respond, but it is not effective in nonresponders. Therefore, it is crucial to establish a reliable method of predicting response before initiation of chemotherapy. Hypercoagulability, which is thought to be because of upregulation of tissue factor (TF) in cancer cells, was reported to be associated with chemoresistance. The aim of this study was to investigate the association between TF expression and response to NACT in esophageal cancer.

Methods

In 67 patients with advanced esophageal cancer, TF expression in pretreatment biopsy samples was evaluated immunohistochemically and correlated with clinicopathologic factors and response to chemotherapy.

Results

TF was expressed by 43.3% of the tumors, but there were no correlations observed with any clinicopathologic parameters examined. Clinical and histologic responses to chemotherapy were significantly worse in TF-positive patients compared with TF-negative patients. Multivariate analysis revealed that TF expression was significantly associated with a poor clinical response (P = 0.0431). TF expression was also independently associated with poor progression-free survival (P = 0.0353).

Conclusions

TF expression levels in pretreatment biopsy samples are useful for predicting response to NACT in advanced esophageal cancer. Further studies of mechanisms underlying the relationship between TF expression and chemosensitivity are needed.  相似文献   
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Phyllodes tumor is an uncommon breast neoplasm characterized by a proliferation of both stromal and epithelial elements. In 1989, two young patients with phyllodes tumors were referred to our surgical department because of the detection of breast lumps. Interestingly, both patients also had epilepsy and had been taking anticonvulsants. An analytical case control study revealed that no significant difference between the control group and phyllodes group was found for various categories. In addition, no anticonvulsant medication had been prescribed in either the control group or the phyllodes group except for these two cases. We herein report two cases of phyllodes tumors occurring in two young epileptic patients.  相似文献   
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