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Heterogeneous Expression (heterogeneous + expression)
Terms modified by Heterogeneous Expression Selected AbstractsHeterogeneous expression of Wnt/,-catenin target genes within colorectal cancerINTERNATIONAL JOURNAL OF CANCER, Issue 9 2007Falk Hlubek Abstract Invasion of common colorectal adenocarcinomas is coupled with a transient loss of epithelial differentiation of tumor cells. Previously, we have shown that dedifferentiated tumor cells at the invasive front (IF) accumulate the transcriptional activator ,-catenin in the nucleus, in contrast to cells of the tumor center. To characterize the cells of these two morphogenic tumor areas, gene expression profiling was performed. Our study demonstrates that intratumorous heterogeneity in colorectal cancer correlates with differential expression of 510 genes between the central tumor region (TC) and the IF. Many genes differentially expressed at the IF are involved in cellular invasion processes like cell motility, cell adhesion and extracellular matrix interaction. This in vivo analysis shows overexpression of known Wnt/,-catenin target genes either in the entire tumor tissue (compared to normal mucosa) or specifically at the IF. Thus, even though all tumor cells overexpress ,-catenin, the existence of at least 2 groups of Wnt/,-catenin target genes selectively activated in different tumor regions is suggested. The concomitant high expression of inflammation- and tissue repair-related genes at the IF supports the hypothesis that an inflammation-activated microenvironment may trigger selective Wnt/,-catenin target gene expression and contribute to the malignant progression of colorectal cancer. © 2007 Wiley-Liss, Inc. [source] Heterogeneous expression of melatonin receptor MT1 mRNA in the rat intestine under control and fasting conditionsJOURNAL OF PINEAL RESEARCH, Issue 2 2006Soták Abstract:, Melatonin is found in mammalian central nervous system and various peripheral tissues including gastrointestinal tract (GIT) where it participates in the regulation of intestinal motility, blood flow, immunomodulation, ion transport, cell proliferation and scavenging of free radicals. Some of these effects are achieved via melatonin binding to specific receptors, MT1 and MT2. As no thorough study on the expression of these receptors in the GIT has yet been done, the aim of this study was to determine the MT1 mRNA expression in the rat intestine under both control and fasting conditions. Our results suggest that MT1 mRNA is present in epithelial as well as subepithelial layer, with higher expression in the latter in all intestinal segments studied. The highest signal of the MT1 transcript along the rostro,caudal intestinal axis was found both in epithelial and subepithelial layers of the duodenum. Nevertheless, duodenal MT1 mRNA expression did not reach the level found in pituitary gland. In a 12:12-hr light:dark cycle a MT1 receptor expression in the subepithelial layer of rat distal colon did not manifest a significant diurnal rhythm. Short-term fasting increased the expression of MT1 transcript in the subepithelial layer of both the small and large intestine. During long-term fasting the increase persisted only in distal colon while a return to control levels was observed in small intestinal segments. In conclusion we demonstrated heterogeneous expression of MT1 receptor in the rat intestine and showed that its expression is up-regulated by nutritional deprivation. [source] Expression of CD44s and CD44v6 in transitional cell carcinomas of the urinary bladder: comparison with tumour grade, proliferative activity and p53 immunoreactivity of tumour cells,APMIS, Issue 11 2007JITKA KUNCOVÁ Alterations of CD44 glycoproteins have been shown to play an important role in progression of various malignancies, including urothelial cancer. We investigated expression patterns of CD44s and CD44v6 in transitional cell carcinoma (TCC) of the urinary bladder in relation to tumour grade, proliferative activity, and immunoreactivity for p53. The selected markers were detected immunohistochemically in 122 samples of TCC. We found a close relationship between CD44s and CD44v6 expression and tumour grade. The extension of positive staining for CD44s and CD44v6 towards the luminal surface was a predominant feature of differentiated carcinomas (grades 1 and 2), suggesting deranged maturation of cancer cells related to their neoplastic transformation. Heterogeneous expression of CD44s and CD44v6 predominated in poorly differentiated tumours (G3,4). However, areas of squamous differentiation within the high-grade tumours displayed strong immunoreactivity for both CD44s and CD44v6. The proliferative activity and p53 overexpression increased with the dedifferentiation of the tumour. The results of this study are discussed in relation to the significance of CD44 expression in TCC and to the explanation for controversial results reported in previous studies on the relationship between CD44 expression and the biological behaviour of urothelial cells. [source] Induction of the vascular endothelial growth factor pathway in the brain of adults with fatal falciparum malaria is a non-specific response to severe diseaseHISTOPATHOLOGY, Issue 2 2010Isabelle M. Medana Medana I M, Day N P J, Roberts R, Sachanonta N, Turley H, Pongponratn E, Hien T T, White N J. & Turner G D H (2010) Histopathology,57, 282,294 Induction of the vascular endothelial growth factor pathway in the brain of adults with fatal falciparum malaria is a non-specific response to severe disease Aims:, Pathological or neuroprotective mechanisms in the brain in severe malaria may arise from microvascular obstruction with malaria-parasitized erythrocytes. This study aimed to investigate the role of hypoxia and induction of the vascular endothelial growth factor (VEGF) pathway in the neuropathophysiology of severe malaria. Methods and results:, Immunohistochemistry was performed on post mortem brain tissue sections from 20 cases of severe malaria and examined for the expression of transcriptional regulators of VEGF [hypoxia-inducible factor-1 alpha (HIF-1,), HIF-2,], DEC-1, VEGF, VEGF receptors 1 and 2, and the activated, phosphorylated VEGF receptor 2 (pKDR). HIFs showed limited protein expression and/or translocation to cell nuclei in severe malaria, but DEC-1, which is more stable and regulated by HIF-1,, was observed. There was heterogeneous expression of VEGF and its receptors in severe malaria and non-malarial disease controls. pKDR expression on vessels was greater in malaria cases than in controls but did not correlate with parasite sequestration. VEGF uptake by malaria parasites was observed. Conclusions:, VEGF and its receptor expression levels in severe malaria reflect a non-specific response to severe systemic disease. Potential manipulation of events at the vasculature by the parasite requires further investigation. [source] Chromogenic in situ hybridization analysis of melastatin mRNA expression in melanomas from American Joint Committee on Cancer stage I and II patients with recurrent melanomaJOURNAL OF CUTANEOUS PATHOLOGY, Issue 9 2006L. Hammock Objective:, To determine whether loss of melastatin (MLSN) is a universal phenomenon in American Joint Committee on Cancer (AJCC) stage I and II melanoma patients who experienced recurrence. Material and methods:, Paraffin blocks of primary melanomas (PMs) were retrieved from 30 patients who had a negative sentinel lymph node biopsy and developed recurrent melanoma (AJCC stage I and II). Chromogenic in situ hybridization (CISH) methods were utilized to evaluate the expression of MLSN mRNA. These results were correlated with clinicopathologic data. Results:, Variable, heterogeneous expression of MLSN mRNA was identified in normal, in situ and invasive melanocytes within and between cases. For the invasive PM component, 24 (80%) had focal, regional or complete loss of MLSN mRNA. The remaining 20% had either regional or total partial downregulation of MLSN mRNA. Intact MLSN mRNA expression was present regionally in 14/30 (47%), with mean relative tumor area of 38%, range 5,85%. Increasing loss of MLSN mRNA significantly correlated with increasing tumor depth and microsatellites (r = 0.1/0.4, p = 0.04). However, thin, AJCC T stage 1a PM had higher relative mean loss than intermediate AJCC T stage 2a/2b/3a thickness PM (65% vs. 34%/48%/25%). Increasing loss of MLSN mRNA significantly impacted on disease free survival (DFS) by multivariate analysis (58 vs. 0% 2 years DFS, , 75 vs. >75% mRNA loss, p = 0.02). Decreased overall survival significantly correlated with increasing age and vascular invasion on multivariate analysis. Conclusion:, Extensive loss of MLSN in PM correlated with aggressive metastatic melanoma. Ancillary testing for MLSN mRNA expression by CISH could offer a means to more accurately identify AJCC stage I and II patients at risk for metastatic disease, who could benefit from adjuvant therapy. [source] Expression and immunogenicity of NY-ESO-1 in hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2006Shinichiro Nakamura Abstract Background and Aim:, The present study was designed to investigate the expression of and humoral response against NY-ESO-1 in patients with hepatocellular carcinoma and to analyze the relationship between expression of NY-ESO-1 mRNA and clinicopathological features. Methods:, NY-ESO-1 mRNA and protein expression in surgically resected hepatocellular carcinoma specimens, adjacent non-cancerous liver and non-tumor bearing liver were examined by reverse transcription-polymerase chain reaction and immunohistochemical staining using a monoclonal antibody against NY-ESO-1 (ES121), respectively. The antibody response to NY-ESO-1 was examined by enzyme-linked immunosorbent assay using recombinant NY-ESO-1 protein. Results:,NY-ESO-1 mRNA was detected in 18 of 41 (43.9%) hepatocellular carcinomas. No NY-ESO-1 mRNA was expressed in 41 paired non-cancerous specimens and 18 specimens histologically diagnosed as liver cirrhosis or chronic hepatitis. Immunohistochemistry revealed heterogeneous expression of NY-ESO-1 protein in three of 18 NY-ESO-1 mRNA-positive hepatocellular carcinomas. None of 23 NY-ESO-1 mRNA-negative hepatocellular carcinomas expressed NY-ESO-1 protein. Antibody against NY-ESO-1 protein was detected in two of 92 patients with hepatocellular carcinoma. Both of these patients had tumors invading main branches of the portal vein. Conclusions:, The present study has demonstrated the expression of NY-ESO-1 mRNA in hepatocellular carcinoma and NY-ESO-1 antibody production in patients with advanced hepatocellular carcinoma. Although the enhancement of NY-ESO-1 protein expression and the activation of immune response of the patients with hepatocellular carcinoma are necessary, NY-ESO-1 has the potential to be a good target molecule for immunotherapy against advanced hepatocellular carcinoma. [source] Deranged expression of the E-cadherin/,-catenin complex and the epidermal growth factor receptor in the clinical evolution and progression of oral squamous cell carcinomasJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 8 2002Agnes Bánkfalvi Abstract Background:, Deranged expression and function of the E-cadherin/,-catenin (E-cad/,-cat) complex and the epidermal growth factor receptor (EGFR) have been implicated in the development and progression of carcinomas. Methods:, To estimate the role of these molecules in oral cancer, we investigated 75 primary oral squamous cell carcinomas (OSCCs) with adjacent normal and/or dysplastic mucosa, 30 paired metastases and 12 recurrences by immunohistochemistry. Results:, All three molecules were constitutionally expressed in the basal/parabasal layers of tumour adjacent ,normal' epithelium, in contrast to a significant increase of EGFR and heterogeneous expression of E-cad/,-cat in dysplasia. In OSCCs, over-expression of EGFR correlated significantly with lower tumour grade and poor prognosis, loss of E-cad was a significant marker for shortened survival, reduced ,-cat staining was a predictive marker for lymph node metastasis. Conclusions:, There is a perturbance in intercellular adhesion molecules and EGFR expression/function in oral cancer with major clinical impact. E-cad and ,-cat seem to inhibit EGFR to enhance the progression of OSCCs. [source] Heterogeneous expression of melatonin receptor MT1 mRNA in the rat intestine under control and fasting conditionsJOURNAL OF PINEAL RESEARCH, Issue 2 2006Soták Abstract:, Melatonin is found in mammalian central nervous system and various peripheral tissues including gastrointestinal tract (GIT) where it participates in the regulation of intestinal motility, blood flow, immunomodulation, ion transport, cell proliferation and scavenging of free radicals. Some of these effects are achieved via melatonin binding to specific receptors, MT1 and MT2. As no thorough study on the expression of these receptors in the GIT has yet been done, the aim of this study was to determine the MT1 mRNA expression in the rat intestine under both control and fasting conditions. Our results suggest that MT1 mRNA is present in epithelial as well as subepithelial layer, with higher expression in the latter in all intestinal segments studied. The highest signal of the MT1 transcript along the rostro,caudal intestinal axis was found both in epithelial and subepithelial layers of the duodenum. Nevertheless, duodenal MT1 mRNA expression did not reach the level found in pituitary gland. In a 12:12-hr light:dark cycle a MT1 receptor expression in the subepithelial layer of rat distal colon did not manifest a significant diurnal rhythm. Short-term fasting increased the expression of MT1 transcript in the subepithelial layer of both the small and large intestine. During long-term fasting the increase persisted only in distal colon while a return to control levels was observed in small intestinal segments. In conclusion we demonstrated heterogeneous expression of MT1 receptor in the rat intestine and showed that its expression is up-regulated by nutritional deprivation. [source] Expression of VEGF-C and VEGF-D as Significant Markers for Assessment of Lymphangiogenesis and Lymph Node Metastasis in Non-Small Cell Lung CancerTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010Yukuan Feng Abstract Vascular endothelial growth factor (VEGF)-C and VEGF-D induce lymphangiogenesis through activation of VEGF receptor 3 (VEGFR-3) and have been implicated in tumor spread to the lymphatic system. Lymph node dissemination critically determines clinical outcome and therapeutic options of patients with non-small cell lung cancer (NSCLC). However, the relationship of VEGF-C, VEGF-D, and lymph node metastasis in cancers, including NSCLC, is still controversial. To evaluate the relationship between lymphangiogenesis and lymph node metastasis, the expression of VEGF-C and VEGF-D in NSCLC tumors were detected by immunohistochemistry and quantitative real-time polymerase chain reaction (QRT-PCR). QRT-PCR revealed that in marginal region VEGF-C and VEGF-D mRNA was significantly higher than in tumor center, and VEGF-D mRNA was also higher than that in peritumoral lung tissue. Immunohistochemically, we observed the same heterogeneous expression of VEGF-C and VEGF-D proteins. The group with high expression of VEGF-C and VEGF-D in marginal region had a higher incidence of lymph node metastasis compared with the group with low expression. Furthermore, the group with high expression of VEGF-D in marginal region had a higher incidence of lymphatic invasion. The group with high peritumoral lymphatic vessel density (LVD) had higher expression of VEGF-C and VEGF-D mRNA compared with the group with low peritumoral LVD. Our studies suggested that the expression of VEGF-C and VEGF-D at invasive edge was significantly associated with lymph node metastasis or lymphatic invasion in patients with NSCLC and may be involved in regulation of lymphangiogenesis and lymph node metastasis in NSCLC. Anat Rec, 2010. © 2010 Wiley-Liss, Inc. [source] Neurogranin expression identifies a novel array of Purkinje cell parasagittal stripes during mouse cerebellar developmentTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 2 2006Matt Larouche Abstract Markers that reveal the parasagittal organization of cerebellar Purkinje cells may be grouped into two classes based on the time during development when they are expressed. In mice, early-onset markers are defined by their heterogeneous expression in clusters of Purkinje cells during late embryogenesis, which disappears shortly following birth. Late-onset markers are generally not expressed until about 1 week after birth and do not reach a stable striped expression pattern until about 3 weeks postnatally. Currently, no endogenous markers are known that are heterogeneously expressed in the temporal gap between these two classes. Here we present immunocytochemical evidence that parasagittal stripes of Purkinje cells express a member of the calpacitin protein family, neurogranin, possibly from as early as embryonic day (E) 13 and definitively from E15, in a pattern that persists up to postnatal day (P) 20. Neurogranin is thus the first endogenous marker of a Purkinje cell subset capable of bridging the temporal gap between the early- and late-onset patterns. In the early neonate, up to five pairs of neurogranin-immunopositive Purkinje cell stripes run parasagittally through the cerebellum, with the exact number dependent on the rostrocaudal position. Expression is lost during postnatal development in a transverse zone-dependent fashion. Purkinje cells in the central and nodular zones lose neurogranin expression between approximately P4 and P6, whereas expression in the posterior zone persists until approximately P20. Neurogranin immunoreactivity will be a valuable tool in helping to clarify the relationships between early- and late-onset patterns. J. Comp. Neurol. 494:215,227, 2006. © 2005 Wiley-Liss, Inc. [source] The PTEN gene in locally progressive prostate cancer is preferentially inactivated by bi-allelic gene deletionTHE JOURNAL OF PATHOLOGY, Issue 5 2006PCMS Verhagen Abstract PTEN is frequently inactivated during the development of many cancers, including prostate cancer, and both bi-allelic and mono-allelic PTEN inactivation may contribute to tumorigenesis. PTEN mutations in clinical cancer specimens can easily be recorded but mono- or bi-allelic gene deletions are often difficult to assess. We performed a comprehensive study to detect PTEN inactivation in 40 locally progressive clinical prostate cancer specimens obtained by transurethral resection of the prostate, utilizing a variety of complementary technical approaches. The methods to detect PTEN deletion included allelotype analysis, dual-colour FISH and array-based CGH. We also applied a novel semi-quantitative approach, assessing the PTEN-WT (wild-type): PTEN- , (pseudogene) ratio (WPR). Structural analysis of PTEN was performed by single-strand conformational polymorphism (PCR-SSCP) and sequencing. PTEN protein expression was assessed by immunohistochemistry. Our data predict complete PTEN inactivation in 12 samples (30%), nine of these by bi-allelic deletion. Loss of one PTEN copy was also detected by several methodologies but the number could not be accurately assessed. Immunohistochemistry indicated the absence of PTEN protein in 15 samples, and heterogeneous expression of the protein in eight tumours. Taken together, these data show that bi-allelic deletion is a major mechanism of PTEN inactivation in locally progressive prostate cancer. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 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