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81.
PURPOSE: The F-box protein S-phase kinase-associated protein 2 (Skp2) is one of the positive regulators of the cell cycle that promote ubiquitin-mediated proteolysis of the cyclin-dependent kinase inhibitor p27. In this study, we investigated the significance of Skp2 expression in human non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Clinicopathologic features and immunohistochemical expression of Skp2 and p27 proteins were studied in 138 patients with NSCLC. Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. To analyze the role of Skp2 in vitro, NSCLC cells were transfected with an Skp2-expressing vector or small interfering RNA. RESULTS: Skp2 was overexpressed in males, smokers, patients with squamous cell carcinomas, and patients with poorly differentiated cancers (P = .034, < .0001, < .0001, and .002, respectively). The multivariant analysis revealed that Skp2 expression is an independent prognostic factor for survival in NSCLC. An inverse relationship of Skp2 with p27 expression was observed (P = .012), and patients with both a higher expression of Skp2 and a lower expression of p27 showed a significantly unfavorable prognosis (P = .0002). In vitro ectopic expression of Skp2 in NSCLC cells reduced the protein level of p27. Conversely, induction of Skp2 siRNA increased the protein level of p27, leading to growth inhibition in NSCLC cells. CONCLUSION: Skp2 overexpression is closely associated with the suppression of p27 and the aggressiveness in NSCLC. It also could be a therapeutic target in NSCLC.  相似文献   
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PURPOSE: Valosin-containing protein (VCP; also known as p97) was shown to be associated with antiapoptotic function and metastasis via activation of nuclear factor kappa-B signaling pathway. In this study, association of VCP expression with recurrence of gastric carcinoma (GC), in which lymphatic vessels are the main route of spread, was examined. PATIENTS AND METHODS: VCP expression in 330 patients with GC (242 males and 88 females) with ages ranging from 26 to 81 years (median, 60 years) was analyzed by immunohistochemistry, in which staining intensity in tumor cells was categorized as weaker (level 1) or equal to or stronger (level 2) than that in endothelial cells. RESULTS: Ninety-four (28.7%) patient cases showed level 1 and 233 patient cases (71.3%) showed level 2 VCP expression. Patients with level 2 expression showed higher rates of large tumor size (P <.0001), undifferentiated histologic subtype (P <.05), presence of vascular and lymphatic invasion (P <.0001 for both), presence of lymph node metastasis (P <.0001), deep tumor invasion (P <.0001), and poorer disease-free and overall survivals (P <.0001 for both) compared with those with level 1 VCP expression. Multivariate analysis revealed VCP expression level as an independent prognosticator for disease-free and overall survival. VCP level was an indicator for disease-free and overall survival in the early (pT1; P <.01 and P <.05, respectively) and advanced (pT2-4; P <.05 for both) group of pathologic tumor-node-metastasis system classification. CONCLUSION: The prognostic significance of VCP expression level in GC was demonstrated.  相似文献   
84.
PURPOSE: Amplification of the MYCN proto-oncogene is strongly correlated with poor outcome in neuroblastoma (NB), although deregulated MYCN is a potent inducer of apoptosis. BIN1 (2q14) encodes multiple isoforms of a Myc-interacting adaptor protein that has features of a tumor suppressor, including the ability to inhibit Myc-mediated cell transformation and to promote apoptosis. We hypothesized that BIN1 may function as a suppressor gene in NB, because Bin1 is highly expressed in neural tissues and binds the Myc Box motifs that are conserved in MycN. EXPERMENTAL DESIGN: Expression of MYCN, total BIN1, and BIN1 isoforms were determined in 56 primary NBs using the real-time PCR. Expression was correlated with biological and genetic features. To determine the functional significance of BIN1 expression we ectopically expressed BIN1 isoforms in NB cell lines with and without MYCN amplification, and assessed clonogenic growth. RESULTS: Four predominant BIN1 isoforms resulting from alternative splicing of exon 12A (a neural tissue-specific exon) and exon 13 (a Myc-binding domain encoding exon) were variably expressed in the 56 primary NBs. Expression of BIN1 was lower in: NBs with MYCN amplification (n = 10) compared with those without, P < 0.03; in International Neuroblastoma Risk Group high-risk NB (n = 19) compared with low- or intermediate-risk NB, P < 0.01; and in metastatic NB (n = 21) compared with localized NB, P < 0.06. BIN1 inactivation by deletion or genomic rearrangement was identified infrequently. Forced expression of BIN1 isoforms containing the Myc-binding domain (with or without exon 12A) inhibited colony formation in NB cell lines with MYCN amplification (P < 0.01) but not in those without. Forced expression of BIN1 isoforms with a MBD deletion did not inhibit colony formation in any cell line assessed. CONCLUSIONS: These data support that reduced BIN1 expression contributes to the malignant phenotype of childhood NB. As we reported previously, BIN1 may function to circumvent MycN-mediated apoptosis in NBs with MYCN amplification.  相似文献   
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Patterns of radiologic response of 10 thymomas treated by preoperative radiotherapy (RT) (18-20 Gy/2 weeks) were determined in conjunction with histologic response. Changes in tumor volume were evaluated with CT scans obtained 5 to 36 days before and 14 to 24 days after the initiation of RT and before surgery. The extent of tumor volume reduction (TR) varied widely (40-78%), while the mean daily volume decrement expressed as a percentage of the pre-RT tumor volume correlated significantly with the pre-RT tumor volume. Histologically, the tumors, all of which were resected 17 to 33 days after RT initiation, generally consisted of predominant fibrous tissues, rare necrotic foci, and few epithelial cells. The TR did not correlate with pre-RT tumor volume, observation period, histologic subtype, or quantity of remaining epithelial cells. The TR of thymomas does not predict RT impact on tumor cells but does reflect the quantity of inherent tumor stroma.  相似文献   
87.
The purpose of this study was to apply an electronic nose system for evaluation of unpleasant odor in tablets containing L-cysteine, an unpleasant odor drug, and demonstrate the odor masking ability of thin-layer sugarless coated tablets, which we have newly developed, by both electronic nose system and sensory evaluations. We demonstrated the qualitative evaluation of the unpleasant odor using air as a reference indicator and the quantitative evaluation of the unpleasant odor using the distances between air and samples in the electronic nose system evaluation. The electronic nose system evaluation was positively and well-correlated with the sensory evaluation by volunteers. We suggest that the electronic nose system evaluation is appropriate as an alternative or a support method for sensory evaluation by volunteers. As the results of both electronic nose system and sensory evaluations, we demonstrated that the thin-layer sugarless coated tablets have excellent masking ability of the unpleasant odor, equivalent to that of sugar-coated tablets due to the dense coating layers.  相似文献   
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PURPOSE: We present results of patients with hepatocellular carcinoma (HCC) treated with proton beam therapy. EXPERIMENTAL DESIGN: We reviewed 162 patients having 192 HCCs treated from November 1985 to July 1998 by proton beam therapy with or without transarterial embolization and percutaneous ethanol injection. The patients in the present series were considered unsuitable for surgery for various reasons, including hepatic dysfunction, multiple tumors, recurrence after surgical resection, and concomitant illnesses. The median total dose of proton irradiation was 72 Gy in 16 fractions over 29 days. RESULTS: The overall survival rate for all of the 162 patients was 23.5% at 5 years. The local control rate at 5 years was 86.9% for all 192 tumors among the 162 patients. The degree of impairment of hepatic functions attributable to coexisting liver cirrhosis and the number of tumors in the liver significantly affected patient survival. For 50 patients having least impaired hepatic functions and a solitary tumor, the survival rate at 5 years was 53.5%. The patients had very few acute reactions to treatments and a few late sequelae during and after the treatments. CONCLUSIONS: Proton beam therapy for patients with HCC is effective, safe, well tolerable, and repeatable. It is the useful treatment mode for either cure or palliation for patients with HCC irrespective of tumor size, tumor location in the liver, insufficient feeding of the tumor with arteries, presence of vascular invasion, impaired hepatic functions, and coexisting intercurrent diseases.  相似文献   
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