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131.
Prognostic factors in laryngeal carcinoma: the role of apoptosis,p53, proliferation (Ki-67) and angiogenesis 总被引:3,自引:0,他引:3
Teppo H Soini Y Melkko J Koivunen P Alho OP 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(4):451-457
Even though the roles of different known or suggested prognostic factors in laryngeal cancer have been studied in detail, clinical stage at time of diagnosis and anatomic subsite of the tumour remain the only practical predictors of clinical outcome and offer the only guidelines in the planning of treatment. In this study, the relative roles of known demographic and clinical prognostic factors, in addition to four histopathological factors, were evaluated in a sample of 100 laryngeal carcinoma patients with multivariate analysis using the Cox regression model. In addition to advanced stage (stage III-IV) (relative hazard of death (HR) 8.9, p=0.01) and supraglottic disease (HR 5.6, p=0.02), high apoptotic index (HR 11.1, p=0.05) was significantly associated with poor survival. Cell proliferation, p53 and angiogenesis did not significantly affect the prognosis. In the future, high degree of apoptosis could be used to identify patients with poor prognosis in laryngeal cancer. 相似文献
132.
Schrader Jürgen Gerlach Eckehart 《Pflügers Archiv : European journal of physiology》1976,367(2):129-135
Summary After prelabeling the adenine nucleotides (ATP, ADP, AMP) of isolated perfused guinea pig hearts with either14C-adenine or14C-adenosine for 35 min, labeled adenosine, inosine, hypoxanthine and cyclic 35-AMP (cAMP) were continuously released into the cardiac perfusate. Determination of the specific activities (SA) of the adenine nucleotides, cAMP, and their breakdown products (adenosine, inosine, hypoxanthine) in tissue and perfusate revealed: Under steady state conditions the SA of adenosine and cAMP in the perfusate were of the same order of magnitude and proved to be many times higher than the SA of the respective precursor adenine nucleotides. This difference was observed regardless whether adenine or adenosine was used as prelabeling substance. The SA of inosine and hypoxanthine in the perfusate were constantly lower than the SA of adenosine. Cardiac ischemia of 6 min, which resulted in a markedly increased formation of adenosine, led to a pronounced decrease in the SA of adenosine released from the heart.Our findings provide evidence that at least two different adenine nucleotide compartments of the heart serve as precursors for the formation of adenosine and cAMP, one characterized by a high, the other by a lower SA. Under normoxic conditions adenosine and cAMP released into the cardiac perfusate are derived mainly from a nucleotide fraction of high SA, which appears to be rather small. During ischemia a second compartment of much lower SA in addition contributes to the formation of adenosine.A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976A preliminary report of part of this work appeared in Biochemistry and Pharmacology of Myocardial Hypertrophy, Hypoxia and Infarction Vol. 7 of Recent advances in studies on cardiac structure and metabolism. (P. Harris, R. J. Bing, A. Fleckenstein, eds.), pp. 171–175. München: Urban & Schwarzenberg 1976 相似文献
133.
134.
An electron-cytochemical investigation was made of oxidation of 3,3-diaminobenzidine (DAB) in the brain of rats and man at different times after death. The oxidation product of DAB was localized in the mitochondria, lipofuscin granules, and erythrocytes. Oxidation of DAB by rat and human brain mitochondria was shown to be only very slightly depressed even 2 days after death.Laboratory of Experimental Pathology and Pathomorphology of the Brain, Institute of Psychiatry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Snezhnevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 757–759, June, 1976. 相似文献
135.
IL-8 mRNA in human gingival epithelial cells (HGECs) is up-regulated by Fusobacterium nucleatum, and up-/down-regulated by Porphyromonas gingivalis in a complex interaction in the early stages (< or = 4 h) after infection. The mechanisms involved in this regulation in response to F. nucleatum and/or P. gingivalis infection, and identification of co-regulated cytokine genes, are the focus of this investigation. Heat, formalin or protease treatment of F. nucleatum cells attenuated the IL-8 mRNA up-regulation. NF-kappaB, mitogen-activated protein kinase (MAPK) p38 and MAPK kinase/extracellular signal-regulated kinase (MEK/ERK) pathways were involved in IL-8 mRNA induction by F. nucleatum. Pretreatment of P. gingivalis with heat, formalin or protease enhanced IL-8 mRNA induction. NF-kappaB, MARK p38, and MEK/ERK pathways were also involved in this induction. In contrast, down-regulation of IL-8 mRNA by P. gingivalis involved MEK/ERK, but not NF-kappaB or MAPK p38 pathways. cDNA arrays analysis revealed that mRNA down-regulation by P. gingivalis is a specific reaction that only a number of genes, e.g. IL-1beta, IL-8, macrophage inflammatory protein-2alpha, and migration inhibitory factor-related protein-14, are affected based on examination of 278 cytokine/receptor genes. These data indicate that F. nucleatum and P. gingivalis trigger specific and differential gene regulation pathways in HGECs. 相似文献
136.
137.
Growth factor-dependent activation of the MAPK pathway in human pancreatic cancer: MEK/ERK and p38 MAP kinase interaction in uPA synthesis 总被引:3,自引:0,他引:3
Increased expression of the hepatocyte growth factor (HGF) receptor (c-met) and urokinase type plasminogen (uPA) correlated
with the development and metastasis of cancers. To investigate the role of HGF/c-met signaling on metastasis in cancer cells
stimulated with HGF, we examined the effects of a specific MEK1 inhibitor (PD98059) and a p38 MAP kinase inhibitor (SB203580)
on HGF-induced uPA expression in pancreatic cancer cell lines, L3.6PL and IMIM-PC2. Pretreatment of PD98059 decreased HGF-mediated
phosphorylation of extracellular receptor kinase (ERK), uPA secretion and expression of matrix metalloproteinases (MMP-2 and
MMP-9) in a dose-dependent manner. In contrast, SB203580 pretreatment increased HGF-stimulated ERK phosphorylation, uPA secretion
and expression of MMPs. SB203580 also reversed the inhibition of HGF-mediated ERK activation and uPA secretion in the PD98059-pretreated
cells. These results suggest that ERK activation by HGF might play important roles in the metastasis of pancreatic cancer
and the p38 MAPK pathway also involved in the HGF-mediated uPA secretion and metastasis by regulation of ERK pathway.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
138.
139.
Suzuki M Okuyama T Yoshikawa K Yamaoka Y Ariyasu T Fujita M Tankawa H Sugiyama T Takahashi R 《Pathology international》1996,46(1):46-53
Overexpression of p53 protein, epidermal growth factor receptor (EGF-R), and c-erbB-2 protein was assessed by immunohistochemical staining of formalin-fixed, paraffin-embedded tissue from 64 invasive breast tumors. The correlation between abnormal expression of each protein and various disease parameters, including lymph node metastasis and histopathologic type and grade was analyzed. Despite the previous proposal, no significant correlation was found between lymph node metastases and overexpression of each gene in the primary tumors. In addition, some metastatic lesions did not always exhibit overexpression, even if it was evident in the primary tumors. Overexpression of c-erbB-2 protein correlated well with Bloom's histological grading. p53 expression was detected most often in tumors with hyperchromatism and more frequent mitosis. Overexpression of c-erbB-2 protein occurred more frequently in p53-positive tumors. The results indicate that abnormal expression of p53 protein causes genetic instability in the early stage of tumor development, resulting in subsequent overexpression of other oncogenes. 相似文献
140.
Eleven single nucleotide polymorphisms and one triple nucleotide insertion of the human TGF-β III receptor gene 总被引:1,自引:0,他引:1
Zippert R Bässler A Holmer SR Hengstenberg C Schunkert H 《Journal of human genetics》2000,45(4):250-253
We found 11 single nucleotide polymorphisms and one triple nucleotide insertion in the cDNA of the human transforming growth
factor β (TGF-β) III receptor gene (TGFBR3) located on 1p33–p32, encoding betaglycan, a component of the TGF-β receptor system. Inside the 5′ untranslated region (UTR),
a G→A polymorphism was identified at position 311. In the open reading frame (ORF), a non-conservative T→C polymorphism was
identified at position 392, and three conservative polymorphisms were found at positions 563 (G→A), 1548 (G→A), and 2370 (C→T).
A triple nucleotide insertion (GCA) was identified at position 1419. Inside the 3′ UTR, six polymorphisms were identified:
four G→A, at positions 2918, 3055, 3098, and 3355; one T→A, at position 3183; and one G→C, at position 3966. In addition to
these changes, some divergences from the published sequence were observed in all 12 chromosomes tested. These included, in
the ORF, an additional C after position 555, two additional G after position 563, and an additional T after position 1388.
No T was found at position 1394. The alterations translate to a changed amino acid sequence. Inside the 3′ UTR, additional
discrepancies were identified. The discovered changes and polymorphisms may be useful for further genetic studies of TGFBR3 receptor deficiencies.
Received: December 22, 1999 / Accepted: February 25, 2000 相似文献