Mitogen-activated protein kinase/extracellular signalregulated protein kinase (MAPK/ERK) is a key molecule in intracellular signal transducing pathways that transport extracellular stimuli from cell surface to nuclei. MAPK/ERK has been revealed to be involved in the physiological proliferation of mammalian cells and also to potentiate them to transform. However, its role in the outgrowth of human hepatocellular carcinoma (HCC) has yet to be clarified. Therefore, in this study, we investigated the activation of MAPK/ERK and its associated gene expression in HCC. MAPK/ERK was activated in 15 of 26 cases of HCC we examined (58%), and its activity level was significantly higher in HCC than in the adjacent non-cancerous lesions. The mitogen-activated protein kinase/extracellular signalregulated protein kinase (MAPK/ERK) was first identified as a protein serine/threonine kinase which could be activated by a number of growth factors, cytokines, and oncogenic promoters 1,2 ; the MAPK/ERK, thereafter, was revealed to be a key molecule which converges several signal transduction pathways and transduces converged signals into nuclei, resulting in various cellular responses including proliferation and differentiation. 3,4 Numerous signals through small guanosine triphosphate (GTP)-binding protein Ras, 5 protein kinase C, 6 and other signal transducing molecules both phosphorylate and activate MAPK kinase kinases. MAPK kinase kinases, in turn, phosphorylate and activate MAPK/ERK kinase. Finally, MAPK/ERK kinase activates two isozymes of MAPK/ERK, p44 ERK1 and p42 ERK2 by phosphorylation on both threonine and tyrosine residues. In this way, signals from extracellular stimuli converge upon MAPK/ERK.Once activated, MAPK/ERK translocates into nuclei, 7-9 in which it induces transcription factors, including c-Fos and c-Jun, or activate them by phosphorylation. 10 These two transcription factors consist of activator protein-1 (AP-1) 11 and bind to AP-1 binding sites of promoter regions to induce transcription of the genes, including cyclin D1, 12 which is required for cell cycle progression in the G0/G1 phase as a G1 cyclin. 13 In addition, previous works indicate that constitutive MAPK/ERK activation results in the transformation of mammalian cells, 3,14 and that its activation is necessary for oncogenic transformation. 3 In this context, alterations in expression and activity of components of the MAPK cascade have been demonstrated in human tumors. [15][16][17] With regard to human hepatocellular carcinoma (HCC), there has been only one report on five patients where MAPK expression and activity were increased in cancerous lesions over noncancerous adjacent lesions 17 ; however, little has been revealed on the involvement of MAPK/ERK in human HCCs.Therefore, the aim of this study is to determine the activation of MAPK/ERK and expression of its associated genes, i.e., transcription factors and cell-cycle related genes, in both human HCCs and their non-cancerous counterparts, and to investigate how MAPK/ERK may be involved in the p...
The c-met protooncogene is a growth factor receptor with tyrosine kinase activity. Recently the hepatocyte growth factor was identified as the ligand for this receptor. Because the hepatocyte growth factor is a most potent mitogen in hepatocytes, possible involvement of c-met expression in hepatocarcinogenesis is suspected. In this study, we examined c-met expression in 23 hepatocellular carcinoma cases by means of Northern-blot analysis and an immunohistochemical study. Northern-blot analysis revealed c-met mRNA expression in the tumors of 6 of 19 patients (31.6%); in the immunohistochemical study, c-met protein was detected in 16 of 23 patients (69.6%). With both methods, c-met was found to be overexpressed in hepatocellular carcinoma compared with the surrounding normal liver. Comprehensive analysis showed that c-met protein expression was correlated with poor-to-moderate differentiation of cancer cells (p < 0.05). Tumor proliferative activity of hepatocellular carcinoma was evaluated by means of Ki-67 labeling index. All cases with increased tumor proliferative activity showed c-met protein expression, although the elevation of proliferative activity in the c-met-positive group was not statistically significant. These data suggest that the overexpression of c-met plays an important role in the development of hepatocellular carcinoma.
SummaryThe status of Fas and Fas ligand (Fas L) expression was investigated in this study for 103 hepatocellular carcinomas (HCC). We studied the expression of the following three factors, Fas and Fas L expression in carcinoma cells and Fas L expression in stromal mononuclear cells (defined as stromal Fas L index). Fas expression in HCC cells was significantly decreased in cases with poor differentiation (P < 0.0001) and of larger size (P = 0.0058). Fas L expression in carcinoma cells was observed exclusively in moderately or poorly differentiated cases. Furthermore, each factor had prognostic significance for disease-free survival (DFS) (P < 0.0001, P = 0.0222 and 0.0027 respectively). We then scored the results of each factor and defined the total score as 'Fas-Fas L risk score'. The P-value of the score for DFS was even lower than that of the clinical stage by multivariate analysis. These results suggest that the evaluation of Fas and Fas ligand expression potentially has a significant prognostic value for DFS of HCC patients, in addition to the clinical stage, and can be regarded as a new prognostic marker. (2000) 82(6), 1211-1217 © 2000 Cancer Research Campaign Article no. bjoc.1999.1065, available online at http://www.idealibrary.com on Research Resources Bank. Cells were cultured in RPMI-1640 medium supplemented with 10% fetal calf serum (FCS) at 37°C in 5% carbon dioxide. Tissue specimens were obtained from 103 patients who had undergone surgery for solitary HCC and three patients for breast carcinoma. The tissues were fixed overnight with 10% buffered formalin. After being washed for over 1 h with water and dehydrated through a graded ethanol series at 4°C, the tissues were immersed three times in xylene pools and four times in paraffin pools and embedded in paraffin. The patient profiles are presented in Table 1. Informed consent was obtained from each patient. Four-micrometre-thick sections for each block were prepared for immunohistochemical examination. AntibodiesTwo kinds of primary antibodies were used in this study. Anti-Fas monoclonal antibody (clone CH-11), the specificity of which had been established previously (Hiramatsu et al, 1994;Mochizuki et al, 1996), was obtained from MBL (Nagoya, Japan). Anti-Fas L polyclonal antibody was from Nichirei (Tokyo, Japan). This antibody specifically recognizes synthetic peptides of the 41st to 54th amino acids located in the intracellular domain of human Fas L. The final dilutions of the primary antibodies were 2.5 µg ml -1 and 10 µg ml -1 , respectively. Immunohistochemical procedureCultured cells were collected, cytocentrifuged onto poly-L-lysinecoated glass slides, immediately fixed in buffered formalin for 1 h, and washed in distilled water for 5 min. Tissue sections were prepared from 4-µm-thick slices from paraffin-embedded specimens. The paraffin was removed in xylene three times, after which the tissues were rehydrated through a graded ethanol series ranging from 100% to 60%. Endogenous peroxidase activity was blocked with 0.3% hydrogen peroxide...
It is challenging to reconstruct normal hip motion after a high hip dislocation. Although total hip arthroplasty (THA) with shortening osteotomy is a solution for high hip dislocation, osteotomy nonunion is a major complication. To improve the rate of osteotomy union, subtrochanteric transverse shortening osteotomy was performed using a modular-type stem, S-ROM, that can be fixed to both the proximal and distal parts of the femur individually with a stepped proximal sleeve and polished distal flutes with fins, respectively. The stem can facilitate union of the osteotomy by maintaining rigid rotational stability and generating compression pressure between bone parts of the femur even in simple transverse osteotomy. Moreover, transverse osteotomy is technically simple and minimizes the damage of the periosteum at the osteotomy. In our series, this procedure was performed on 6 hips in 6 patients with high hip dislocation. The mean follow-up period was 8.1 years. Osteotomy union was achieved in all patients for a mean of 8.8 weeks. This procedure is a good option for surgical treatment of high hip dislocation.
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