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This study was set to investigate the relation between autophagic activity and the aggressiveness of cutaneous squamous cell carcinomas (SCC), as indicated by tumor thickness and proliferative activity. The anti-LC3A antibody, recognizing both the soluble and the autophagosome-bound forms of the protein, and a standard immunohistochemical technique were applied to 75 cutaneous SCC of variable tumor thickness. The study was complemented by staining for MIB1. Three patterns of LC3A reactivity were recognized: diffuse cytoplasmic, cytoplasmic/perinuclear, and "stone-like" structures (SLS), that is, large, rounded, densely stained amorphous material, 5 μm on average, enclosed within cytoplasmic vacuoles. Higher numbers of SLS were counted in >6-mm-thick SCC compared with the intermediate-thickness tumors (2.1-6 mm) and the <2-mm-thick tumors; the mean recorded values, being 8.8, 4.55, and 1.55, respectively, were statistically significant. The diffuse cytoplasmic staining showed a nearly inverse trend, whereas the perinuclear pattern, expressed in <10% of the total, was not evaluated. With regard to MIB1 proliferation index, this increased with tumor thickness and, in linear regression analysis, was directly linked with SLS counts and inversely with the cytoplasmic pattern. These data suggest that autophagic activity in SCC, when expressed as high LC3A/SLS counts, can be regarded as an indicator of tumor aggressiveness.  相似文献   
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PURPOSE: Tumor hypoxia and low intrinsic radiosensitivity may counteract the efficacy of standard radiotherapy for locally advanced head and neck cancer (HNC). We investigated the involvement of hypoxia-regulated proteins (Hypoxia inducible factors HIF1alpha, HIF2alpha and carbonic anhydrase CA9) in HNC resistance to accelerated and hypofractionated radiotherapy. MATERIALS AND METHODS: Thirty-nine patients with locally advanced HNC received 15 daily fractions of 3.4 Gy amounting to a total tumor dose of 51 Gy (equivalent to 63 Gy in four weeks--one week split); this was combined with platinum chemotherapy and amifostine cytoprotection administered subcutaneously. Immunohistochemical analysis of hypoxia-regulated proteins, namely HIF1alpha, HIF2alpha and CA9, was performed in formalin-fixed paraffin-embedded tissues obtained prior to radio-chemotherapy. RESULTS: HIF1alpha and HIF2alpha were expressed in the nuclei and cytoplasm of cancer cells, while CA9 had a membrane reactivity. A high expression of HIF1alpha, HIF2alpha and CA9 was noted in 21/39 (53.8%), 20/39 (51.3%) and 23/39 (58.9%) cases, respectively. Complete response was obtained in 85.2% of patients and HIF1alpha was marginally related with persistent disease after RT (p = 0.05). HIF1alpha was significantly associated with poor local relapse free survival (LRFS) (p = 0.006) and overall survival (p = 0.008), whilst HIF2alpha was not. A significant association of CA9 expression with poor LRFS was noted (p = 0.01). CONCLUSION: In accord with previously reported studies, high levels of the hypoxia regulated proteins HIF1alpha and CA9 in HNC predict resistance to platinum based radio-chemotherapy. Whether HIF2alpha expressing tumors are more sensitive to larger radiotherapy fractions, compared to standard radiotherapy fractionation, is an issue that deserves further investigation.  相似文献   
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Myxoid leiomyosarcoma is an extremely rare variant of leiomyosarcoma, masquerading almost to perfection as a benign lesion. For, indeed, the tumor lacks the defining features of high mitotic activity, cellular atypia or necrosis, and the microscopic picture is dominated by abundant myxoid stroma containing sparse spindle cells. We report here such a case occurring in the uterus and discuss the differential diagnosis. The relevant literature is reviewed.  相似文献   
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There have been a number of reports on cervical carcinomas, both invasive and intraepithelial (CIN III), indicating the presence of intracellular mucins in the absence of glandular differentiation. Yet, the expression of such cells in the normal/original squamous epithelium of the cervix remains unexplored. We investigated the presence of mucin-distended goblet cells at this site, after examining retrospectively normal cervices from 250 hysterectomy specimens. Goblet cells were detected in 3.2% (8/250) of the cervices examined using haematoxylin and eosin stained sections and confirmed by mucin histochemistry: alcian blue (AB) pH 2.5, periodic acid-Schiff reaction with and without diastase digestion (PAS-d, PAS) and the combined AB/PAS. Additional sections were stained with Diazo and Masson-Fontana for argentaffin granules and Grimelius for argyrophil cells, but were all negative and no other cell types were identified. It is believed that this incomplete type of intestinal metaplasia is an acquired change in the cervix, derived from multi-potential stem cells of Müllerian duct origin.  相似文献   
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BACKGROUND AND AIMS: Angiogenesis is an important component of tissue regeneration. As Inflammatory bowel disease (IBD) involves inflammation, ulceration, and regeneration of the intestinal mucosa, angiogenesis may be an integral part of IBD pathology. This study investigated the role of vascular endothelial growth factor in IBD. PATIENTS AND METHODS: The VEGF plasma (pVEGF) and serum (sVEGF) levels were assessed in patients with ulcerative colitis (UC; n=50) or Crohn's disease (CD; n=44) and in healthy controls (n=23). The immunohistochemical expression of VEGF was also assessed in surgical material from 11 patients with active IBD. RESULTS. Overall the sVEGF levels ranged from 30-899 pg/ml (median 200 pg/ml) and were significantly higher than the pVEGF levels (range 20-80 pg/ml, median 30 pg/ml). pVEGF levels were significantly lower in patients with active and quiescent CD than in healthy controls. Despite the lower pVEGF levels noted also for patients with UC, the difference was not significant. sVEGF levels were also reduced in patients with IBD, but the difference was not significant. No association of pEGF/sVEGF with beta-thromboglobulin and platelet factor 4 levels (markers of platelet activation) was noted. On immunohistochemistry VEGF was not expressed in the inflammatory component (lymphocytes and macrophages), the fibroblasts, or the muscular layer of the intestinal wall. The intestinal epithelium was negative in CD, while a cytoplasmic reactivity was noted in UC and normal controls. CONCLUSION. As VEGF is a vascular and epithelial cell survival factor, the defective VEGF response ability, confirmed here for patients with CD, may be a key element in the pathology of the disease. The pathology of UC, however, seems not to be VEGF dependent.  相似文献   
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The Ity/Lsh/Bcg locus encodes the macrophage protein Slc11a1/Nramp1, which protects inbred mice against infection by diverse intracellular pathogens including Leishmania, Mycobacterium, and Salmonella. Human susceptibility to infectious and inflammatory diseases, including rheumatoid arthritis, inflammatory bowel disease, and tuberculosis, shows allelic association with a highly polymorphic regulatory, Z-DNA-forming microsatellite of (GT/AC)n dinucleotides within the proximal SLC11A1 promoter. We surmised that cis-acting allelic polymorphisms may underlie heritable differences in SLC11A1 expression and phenotypic variation in disease risk. However, it is unclear what may underlie such variation in SLC11A1 allele expression. Here we show that hypoxia-inducible Factor 1 (HIF-1) regulates allelic variation in SLC11A1 expression by binding directly to the microsatellite during macrophage activation by infection or inflammation. Targeted Hif-1alpha ablation in murine macrophages attenuated Slc11a11 expression and responsiveness to S typhimurium infection. Our data also showed that HIF-1 may be functionally linked to complex prototypical inflammatory diseases associated with certain SLC11A1 alleles. As these alleles are highly polymorphic, our finding suggests that HIF-1 may influence heritable variation in SLC11A1-dependent innate resistance to infection and inflammation within and between populations. This report also suggests that microsatellites may play critical roles in the directional evolution of complex heritable traits by regulating gene expression phenotypes.  相似文献   
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