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Glut1 Expression (glut1 + expression)
Selected AbstractsImmunodetection of GLUT1, p63 and phospho-histone H1 in invasive head and neck squamous carcinoma: correlation of immunohistochemical staining patterns with keratinizationHISTOPATHOLOGY, Issue 6 2006D E Burstein Aims :,To examine invasive head and neck squamous carcinomas for expression of GLUT1, a glucose transporter and marker of increased glucose uptake, glycolytic metabolism and response to tissue hypoxia; p63, a p53 homologue that is a marker of the undifferentiated proliferative basaloid phenotype; and phospho-histone H1, a marker of activation of the cell cycle-promoting cyclin-dependent kinases 1 and 2. Methods :,Routinely processed slides from 34 invasive squamous carcinomas, including 25 with intraepithelial components, were immunostained with anti-GLUT1 (Chemicon), anti-p63 (4A4, Santa Cruz), and antiphospho-histone H1 (monoclonal 12D11). Results :,In keratinizing carcinomas, all three markers were most commonly immunodetected peripherally, with loss of expression in central keratinized zones. In contrast, in non-keratinizing carcinomas, p63 and phospho-histone H1 expression was most commonly observed throughout tumour nests and anti-GLUT1 stained in a pattern suggestive of hypoxia-induced expression (,antistromal' staining), in which cells at the tumour,stromal interface were GLUT1, and cells in central, perinecrotic zones showed progressive induction of GLUT1. Intraepithelial components also displayed basal and ,antibasal' GLUT1 staining patterns, homologous to the pro- and antistromal patterns in invasive carcinoma; basal patterns in intraepithelial lesions appeared to be more predictive of keratinizing invasive carcinoma and antibasal intraepithelial staining more predictive of non-keratinizing poorly differentiated carcinomas. Conclusions :,Keratinizing and non-keratinizing squamous carcinomas differ in expression patterns of GLUT1, p63 and phospho-histone H1. In the former, all three markers were typically suppressed in conjunction with keratinization; in the latter, GLUT1 expression was more likely to occur in a hypoxia-inducible pattern and expression of p63 and phospho-histone H1 was unsuppressed. GLUT1 expression patterns in intraepithelial lesions may be predictive of the differentiation status of the associated invasive carcinoma. [source] Nutritional channels in breast cancerJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 9b 2009Alejandro Godoy Abstract Breast cancers increase glucose uptake by increasing expression of the facilitative glucose transporters (GLUTs), mainly GLUT1. However, little is known about the relationship between GLUT1 expression and malignant potential in breast cancer. In this study, expression and subcellular localization of GLUT1 was analysed in vivo in breast cancer tissue specimens with differing malignant potential, based on the Scarff-Bloom-Richardson (SBRI, II, III) histological grading system, and in vitro in the breast cancer cell lines, MDA-MB-468 and MCF-7, and in MDA-MB-468 cells grown as xenografts in nude athymic BALB/c male mice. In situ hybridization analyses demonstrated similar levels of GLUT1 mRNA expression in tissue sections from breast cancers of all histological grades. However, GLUT1 protein was expressed at higher levels in grade SBRII cancer, compared with SBRI and SBRIII, and associated with the expression of the proliferation marker PCNA. Immunolocalization analyses in SBRII cancers demonstrated a preferential localization of GLUT1 to the portions of the cellular membrane that faced neighbouring cells and formed ,canaliculi-like structures', that we hypothesize could have a potential role as ,nutritional channels'. A similar pattern of GLUT1 localization was observed in confluent cultures of MDA-MB-468 and MCF-7, and in MDA-MB-468 cells grown as xenografts, but not in the normal breast epithelial cell line HMEC. However, no relationship between GLUT1 expression and malignant potential of human breast cancer was observed. Preferential subcellular localization of GLUT1 could represent a physiological adaptation of a subset of breast cancer cells that form infiltrative tumours with a nodular growth pattern and that therefore need a major diffusion of glucose from blood vessels. [source] Sodium valproate inhibits glucose transport and exacerbates Glut1-deficiency in vitroJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 4 2005Hei Yi Wong Abstract Anticonvulsant sodium valproate interferes with brain glucose metabolism. The mechanism underlying such metabolic disturbance is unclear. We tested the hypothesis that sodium valproate interferes with cellular glucose transport with a focus on Glut1 since glucose transport across the blood-brain barrier relies on this transporter. Cell types enriched with Glut1 expression including human erythrocytes, human skin fibroblasts, and rat astrocytes were used to study the effects of sodium valproate on glucose transport. Sodium valproate significantly inhibited Glut1 activity in normal and Glut1-deficient erythrocytes by 20%,30%, causing a corresponding reduction of Vmax of glucose transport. Similarly, in primary astrocytes as well as in normal and Glut1-deficient fibroblasts, sodium valproate inhibited glucose transport by 20%,40% (P,<,0.05), accompanied by an up to 60% downregulation of GLUT1 mRNA expression (P,<,0.05). In conclusion, sodium valproate inhibits glucose transport and exacerbates Glut1 deficiency in vitro. Our findings imply the importance of prudent use of sodium valproate for patients with compromised Glut1 function. J. Cell. Biochem. © 2005 Wiley-Liss, Inc. [source] Sodium/iodide symporter expression in primary lung cancer and comparison with glucose transporter 1 expressionPATHOLOGY INTERNATIONAL, Issue 2 2009Do Y. Kang The aim of the present study was to evaluate the expression of sodium/iodide symporter (NIS) and glucose transporter 1 (Glut1) in 139 primary lung cancers on immunohistochemistry, and to determine the diagnostic utility of NIS as an imaging reporter. Immunoreactivity for NIS and Glut1 was noted in 75 (54.0%) and 72 (51.8%) of the 139 cases, respectively. Analysis of NIS expression on Western blot confirmed the immunohistochemistry. NIS expression was significantly higher in the adenocarcinomas than in the other carcinomas, and Glut1 expression was significantly higher in the squamous cell carcinomas than in the other carcinomas (each P < 0.0001). The frequency of NIS expression in those carcinomas lacking Glut1 expression was significantly higher than in those with Glut1 expression (P = 0.012). Among 64 adenocarcinomas, the frequency of the NIS(+)/Glut1(,) phenotype was 61.0%, which was the most frequent expression pattern. By studying the expression pattern of NIS in lung cancer, the present paper provides a helpful foundation for examining the potential utility of NIS-mediated radioiodide as an alternative diagnostic modality, especially for the management of patients with lung adenocarcinoma lacking Glut1 expression. [source] Glut3 Expression in Biopsy Specimens of Laryngeal Carcinoma Is Associated With Poor Survival,THE LARYNGOSCOPE, Issue 2 2002Susan Baer MD Abstract Objectives/Hypothesis The aim of the study was to determine the clinical significance of the expression of Glut1 and Glut3 proteins in biopsy specimens of squamous cell carcinoma (SCC) of the larynx. Study Design A retrospective study. Methods Using immunohistochemistry, we immunostained sections of formalin-fixed, paraffin-embedded tissues from 48 biopsies of invasive SCC of the larynx for Glut1 and Glut3. The percentages of positive cells were recorded, then correlated with overall patient survival using the Kaplan-Meier method and the Breslow-Gehan-Wilcoxon test for statistical significance. Results All cases were positive for Glut1, and Glut1 expression was not associated with survival difference at any cut-off value. Eighteen (38%) of the cases were Glut3-negative and 30 (62%) were Glut3-positive. Glut3-positive cases were associated with poorer survival than Glut3-negative cases (P = .0336). No significant difference was found between Glut3-negative and Glut3-positive groups in respect to sex, tumor site (glottic vs. supraglottic), nodal or distant metastasis, or treatment modality. However, there were significantly more poorly differentiated tumors in the Glut3-positive group than in the Glut3-negative group (27% vs. 0%, respectively;P = .0182, Fisher's Exact Test). After poorly differentiated tumors were excluded from the survival analysis, Glut3 immunoreactivity remained a significant marker of poor prognosis (P = .0385). Conclusion Immunohistochemical detection of Glut3 in biopsy specimens of SCC of the larynx is a marker of poorer prognosis. [source] | ||||||||||