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Background: In oral lichen planus (OLP), destruction of the basal cell layer, which is one of the characteristic histological features, is seen and many changes in cell proliferation, cell repair and cell death occur in the injured mucosal epithelium.Methods: We studied mucosal tissues from 19 patients of OLP and 10 controls, with immunohistochemistry for Ki-67, p53, cyclin dependent kinase inhibitors (CDKI) and cyclins. Mitotic count was calculated. TUNEL assay was also performed for evaluation of apoptotic cell death.Results: Mitotic count, Ki-67 and cyclin D1 labeling indices in the basal and parabasal layers of OLP mucosa were elevated in comparison with those of controls. p53, p21Cip1 and TUNEL indices of OLP mucosa were also increased.Conclusions: These complex changes, which concomitantly occur in the injured mucosal epithelium, could contribute to the development and maintenance of characteristic mucosal epithelial architectures seen in OLP. [ABSTRACT FROM AUTHOR]

Twenty-four specimens of squamous cell carcinoma of the tongue were immunostained for heat shock proteins (HSPs) to reveal differences in stainability among normal epithelium, dysplasia and carcinoma and to clarify the prognostic significance of HSPs in comparison with survival period, clinical stage, lymph node metastasis, histological grade, and p53 immunostaining. Normal epithelium was positively stained in the suprabasal layer for HSP60 and HSP70, but was negative for HSP27 and HSP90. Dysplastic lesions were positive for HSP27, HSP70 and HSP90, but stained variously for HSP60. In squamous cell carcinoma, the cytoplasm of suprabasal tumor cells was often positive for HSP27 and HSP90 (18/24, 17/24, respectively). Although HSP immunohistochemistry has revealed changes in HSP expression during tumorigenesis of squamous epithelium of the tongue, there was no correlation between HSP staining and survival period, stage, lymph node metastasis, histological grade or p53 immunostaining. [ABSTRACT FROM AUTHOR]

To elucidate interactions between the glucose transport system and hepatic glucose production in the tumour-bearing state, glycogen storage, expression of glucose transporter isoform 2 (Glut 2) and activities of glucose-6-phosphatase (G-6-Pase) and hexokinase were histochemically examined in hepatocytes of tumour-bearing rats. Five male F344 rats, subcutaneously inoculated with methylcholanthrene(MCA)-induced sarcoma cells were compared with five pair-fed animals and four ad libitum fed controls. Glycogen storage was markedly decreased in liver cells of tumour-bearing rats compared to in those of control animals. Glut 2 immunoreactivity was uniformly seen in the cellular membrane of hepatocytes from control animals. In rats bearing sarcoma, the staining intensity was significantly decreased, suggesting that Glut 2 with its bi-directional transport capacity was down-regulated in the tumour-bearing state. Positive staining for hexokinase activity was located in the perivenous area in livers from control animals and was more diffusely located and more intense in livers from tumour-bearing animals. G-6-Pase activity, limited to the peripheral area in livers from controls, extended to the intermediate area and had stronger reactivity in livers from tumour-bearing animals. In the tumour-bearing cachectic condition, glucose may be partially consumed by a futile cycle, hepatic metabolic zonation was disturbed, and the release of glucose from the liver may not be mediated by a facilitative glucose transporter-2. [ABSTRACT FROM AUTHOR]