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Expression of p53 and c-myc was investigated and compared with cell proliferative activity in a series of 40 hepatocellular carcinomas (HCC), by means of enhanced immunohistochemistry. p53 expression was demonstrated in 5 out of 40 HCC (12.5%) with the incidence increasing in proportion to the histological grading of malignancy: thus, 0% of well-differentiated, 6.9% of moderately differentiated and 33.3% of poorly differentiated lesions were positive. The proliferating-cell nuclear antigen (PCNA) labeling index also showed a statistically significant increase with this grading. Distribution patterns of PCNA-positive cell were divided into four types: scatter, marginal, mosaic and diffuse. Four HCC cases, predominantly of the poorly differentiated type, exhibited the diffuse pattern. Generally, p53 overexpression corresponded well with PCNA positivity. In contrast, there was no correlation between c-myc overexpression, found in 19 out of 40 HCC (47.5%), and histological grading of HCC or PCNA labeling index. The distribution pattern of c-myc-positive HCC cells was also different from that of PCNA and p53. Our results suggest that p53 overexpression closely relates to proliferation of HCC cells. Furthermore, there may be a consistent difference in regulatory mechanisms between p53 and c-myc expression in multistep hepatocarcinogenesis.  相似文献   
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High-grade non-muscle-invasive bladder cancer (Non-MIBC) has a high risk of stage progression to muscle-invasive bladder cancer (MIBC) and could be managed either conservatively by transurethral resection of bladder tumor (TURBT) or more aggressively by radical cystectomy. The selection of patients who may benefit from early radical intervention is a challenge. To define useful prognostic markers for progression, we analyzed clinicopathological features and immunohistochemical expression patterns of E2F1, p27, survivin, p53, EZH2, IMP3, TSC1/hamartin, fatty acid synthase, androgen receptor, 14-3-3σ, MAGEA4, and NY-ESO-1 on 118 cases of high-grade Non-MIBC. During the mean follow-up period of 64.3 months, progression occurred in 18 patients (15.3%). Histologically, large amount of invasive component (> 50%) was noted in 35 cases (29.7%) and was strongly associated with progression. Among the 12 biomarkers, high expressions of E2F1 and nuclear p27 were noted in 46 cases (40.0%) and 14 cases (12.7%), respectively, and were associated with frequent progression. Using multivariate analysis, the proportion of invasive component and high E2F1 expression were independent prognostic factors for the prediction of progression. Our results indicated that large amount of invasive carcinoma component and high expressions of p27 and E2F1 were predictive markers for progression in Non-MIBC. Therefore, we suggest that these parameters, especially proportion of invasive carcinoma component and E2F1 expression, should be evaluated during pathologic examination and considered during selection of the appropriate management strategy for high grade Non-MIBC patients.  相似文献   
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Background: The detailed mechanisms of knee osteoarthritis (OA) pain have not been clarified, but involvement of inflammatory cytokines such as tumor necrosis factor-alpha (TNF) has been suggested. The present study aimed to investigate the more detailed neurological involvement of TNF in joint pain using a TNF-knockout mouse OA model. Methods: The right knees of twelve-week-old C57BL/6J wild and TNF-deficient knockout (TNF-ko) mice (n=15, each group) were given a single intra-articular injection of 10 µg monoiodoacetate in 10 mL sterile saline. The left knees were only punctured as the control. Evaluations were performed immediately after the injection (baseline) and at 7, 14, and 28 days after the injection with a subsequent intra-articular injection of neurotracer into both knees. The animals were evaluated for immunofluorescence of the lumbar dorsal root ganglia (DRG) innervating the knee joints. The injected knees were observed macroscopically and mouse pain-related behaviors were scored. Results: Macroscopic observation showed similar knee OA development in both wild and TNF-ko mice. Calcitonin gene-related peptide (CGRP, a neuropeptide identified as a inflammatory pain-related biomarker) was significantly increased in DRG neurons innervating OA-induced knee joints with significantly less CGRP expression in TNF-ko animals. Pain-related behavior scoring showed a significant increase in pain in OA-induced joints, but there was no significant difference in pain observed between the wild and TNF-ko mice. Conclusions: The result of the present study indicates the possible association of TNF-alpha in OA pain but not OA development.  相似文献   
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