207 resultados para HYALURONAN SYNTHASES
Resumo:
We collected a series of 136 lung/bronchial and 56 matched lung parenchyma tissue samples from patients who underwent lung/bronchial biopsies and presented invasive carcinoma after lung surgery. The lung/bronchial samples included basal cell hyperplasia, squamous metaplasia, moderate dysplasia, adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma. Matched lung parenchyma tissue samples included 25 squamous cell carcinomas and 31 adenocarcinomas. Immunohistochemistry was performed to analyze for the distribution of hyaluronidase (Hyal)-1 and −3, and hyaluronan synthases (HAS)-1, −2, and −3. Hyal-1 showed significantly higher expression in basal cell hyperplasia than in moderate dysplasia (P=0.01), atypical adenomatous hyperplasia (P=0.0001), or severe dysplasia (P=0.03). Lower expression of Hyal-3 was found in atypical adenomatous hyperplasia than in basal cell hyperplasia (P=0.01) or moderate dysplasia (P=0.02). HAS-2 was significantly higher in severe dysplasia (P=0.002) and in squamous metaplasia (P=0.04) compared with basal cell hyperplasia. HAS-3 was significantly expressed in basal cell hyperplasia compared with atypical adenomatous hyperplasia (P=0.05) and severe dysplasia (P=0.02). Lower expression of HAS-3 was found in severe dysplasia compared with squamous metaplasia (P=0.01) and moderate dysplasia (P=0.01). Epithelial Hyal-1 and −3 and HAS-1, −2, and −3 expressions were significantly higher in pre-neoplastic lesions than in neoplastic lesions. Comparative Cox multivariate analysis controlled by N stage and histologic tumor type showed that patients with high HAS-3 expression in pre-neoplastic cells obtained by lung/bronchial biopsy presented a significantly higher risk of death (HR=1.19; P=0.04). We concluded that localization of Hyal and HAS in lung/bronchial pre-neoplastic and neoplastic lesions was inversely related to malignancy, which implied that visualizing these factors could be a useful diagnostic procedure for suspected lung cancer. Finalizing this conclusion will require a wider study in a randomized and prospective trial.
Resumo:
Among the most common features of highly invasive tumors, such as lung adenocarcinomas (AD) and squamous cell carcinomas (SqCC), is the massive degradation of the extracellular matrix. The remarkable qualitative and quantitative modifications of hyaluronidases (HAases), hyaluronan synthases (HAS), E-cadherin adhesion molecules, and the transforming growth factor β (TGF-β) may favor invasion, cellular motility, and proliferation. We examined HAase proteins (Hyal), HAS, E-cadherin, and TGF-β profiles in lung AD subtypes and SqCC obtained from smokers and non-smokers. Fifty-six patients, median age 64 years, who underwent lobectomy for AD (N = 31) and SqCC (N = 25) were included in the study. HAS-1, -2 and -3, and Hyal-1 and -3 were significantly more expressed by tumor cells than normal and stroma cells (P < 0.01). When stratified according to histologic types, HAS-3 and Hyal-1 immunoreactivity was significantly increased in tumor cells of AD (P = 0.01) and stroma of SqCC (P = 0.002), respectively. Tobacco history in patients with AD was significantly associated with increased HAS-3 immunoreactivity in tumor cells (P < 0.01). Stroma cells of SqCC from non-smokers presented a significant association with HAS-3 (P < 0.01). Hyal, HAS, E-cadherin, and TGF-β modulate a different tumor-induced invasive pathway in lung AD subgroups and SqCC. HAases in resected AD and SqCC were strongly related to the prognosis. Therefore, our findings suggest that strategies aimed at preventing high HAS-3 and Hyal-1 synthesis, or local responses to low TGF-β and E-cadherin, may have a greater impact in lung cancer prognosis.
Resumo:
Reasons for performing study: Alternative methods to evaluate the joint condition in asymptomatic osteochondrosis dissecans (OCD) and other joint diseases may be useful. Objectives: To investigate possible changes in synovial fluid composition that may lead to joint conditions in asymptomatic OCD, in mature horses. Methods: Animals aged >2 years, of different breeds, with OCD in the intermediate ridge of distal tibia, symptomatic or not, were studied. Synovial fluid samples (10 healthy; 11 asymptomatic OCD; 25 symptomatic OCD) were collected by arthroscopy from 29 horses. Glycosaminoglycans (GAGs) were analysed by a combination of agarose gel electrophoresis and enzymatic degradation with specific GAG lyases. The viscosity, white blood cell (WBC) count, protein concentration and hyaluronic acid (HA) molecular weight were also determined. Results: The method used here to analyse synovial fluid GAGs is reliable, reproducible and specific. The main synovial fluid GAGs are HA and chondroitin sulphate (CS), 93% and 7% respectively in normal horses. In symptomatic OCD, the concentrations of both increased (expressed as GAG/urea ratios), but CS increased more. The CS increased also in asymptomatic OCD. An inflammatory reaction was suggested by the increased WBC counts in OCD. The molecular weight of the synovial fluid HA was reduced in OCD, explaining the lower viscosity observed. Conclusions: The increased CS in synovial fluid of OCD joints in mature horses suggests that the synovial fluid CS and the WBC count are good markers of the joint conditions, allowing the identification of pathological phase in joint diseases. Potential relevance: The analysis of synovial fluid GAGs shows that cartilage damage occurs even in asymptomatic OCD, implying that arthroscopic removal of osteochondral fragments should be performed even in asymptomatic OCD.
Resumo:
The “parallel-up” packing in cellulose Iα and Iβ unit cells was experimentally demonstrated by a combination of direct-staining the reducing ends of cellulose chains and microdiffraction-tilting electron crystallographic analysis. Microdiffraction investigation of nascent bacterial cellulose microfibrils showed that the reducing end of the growing cellulose chains points away from the bacterium, and this provides direct evidence that polymerization by the cellulose synthase takes place at the nonreducing end of the growing cellulose chains. This mechanism is likely to be valid also for a number of processive glycosyltransferases such as chitin synthases, hyaluronan synthases, and proteins involved in the synthesis of nodulation factor backbones.
Resumo:
Spinal cord injury (SCI) is a devastating neurological disorder that affects thousands of people each year. Although in recent decades significant progress has been made in relation to understanding the molecular and cellular events underlying the nervous damage, spinal cord injury is still a highly disabling condition for which there is no curative therapy. People affected by spinal cord injuries manifested dysfunction or loss, temporary or permanent, of motor, sensory and / or autonomic functions depending on the spinal lesion damaged. Currently, the incidence rate of this type of injury is approximately 15-40 cases per million people worldwide. At the origin of these lesions are: road accidents, falls, interpersonal violence and the practice of sports. In this work we placed the hypothesis that HA is one of the component of the scar tissue formed after a compressive SCI, that it is likely synthetised by the perilesional glial cells and that it might support the permeation of the glial scar during the late phase of SCI. Nowadays, much focus is drawn on the recovery of CNS function, made impossible after SCI due to the high content of sulfated proteoglycans in the extracellular matrix. Counterbalancing the ratio between these proteoglycans and hyaluronic acid could be one of the experimental therapy to re-permeate the glial scar tissue formed after SCI, making possible axonal regrowth and functional recovery. Therefore, we established a model of spinal cord compression in mice and studied the glial scar tissue, particularly through the characterization of the expression of enzymes related to the metabolism of HA and the subsequent concentration thereof at different distances of the lesion epicenter. Our results show that the lesion induced in mice shows results similar to those produced in human lesions, in terms of histologic similarities and behavioral results. but these animals demonstrate an impressive spontaneous reorganization mechanism of the spinal cord tissue that occurs after injury and allows for partial recovery of the functions of the CNS. As regards the study of the glial scar, changes were recorded at the level of mRNA expression of enzymes metabolizing HA i.e., after injury there was a decreased expression of HA synthases 1-2 (HAS 1-2) and an increase of the expression HAS3 synthase mRNA, as well as the enzymes responsible for the HA catabolism, HYAL 1-2. But the amount of HA measured through the ELISA test was found unchanged after injury, it is not possible to explain this fact only with the change of expression of enzymes. At two weeks and in response to SCI, we found synthesized HA by reactive astrocytes and probably by others like microglial cells as it was advanced by the HA/GFAP+ and HA/IBA1+ cells co-location.
Resumo:
OBJECTIVE: We evaluated whether vaginal concentrations of hyaluronan were altered in women with recurrent vulvovaginal candidiasis (RVVC). STUDY DESIGN: Lavage samples from 17 women with acute RVVC, 27 women who were receiving a maintenance antifungal regimen, and 24 control women were tested for hyaluronan and interleukin (IL)-6, IL-12, and IL-23 by enzyme-linked immunosorbent assay. RESULTS: Median vaginal hyaluronan concentrations were 33.8 ng/mL (range, 21.6-66.3 ng/mL) in women with acute RVVC, 15.0 ng/mL (range, 11.2-50.6 ng/mL) in women who were receiving maintenance therapy, and 4.2 ng/mL (range, 3.6-12.0 ng/mL) in control subjects (P <= .02). The vaginal hyaluronan concentration was 27.4 ng/mL (range, 15.4-37.7 ng/mL) when Candida was detected by microscopy and 9.5 ng/mL (range, 7.7-14.6 ng/mL) in microscopy-negative cases (P = .0354). Elevated hyaluronan levels were associated with itching plus burning (40.7 ng/mL) or itching plus discharge (42.1 ng/mL), as opposed to itching only (6.2 ng/mL; P = .0152). Hyaluronan and IL-6 levels were correlated (P = .0009). CONCLUSION: Hyaluronan release is a component of the host response to a candidal infection and may contribute to symptoms.
Resumo:
Hyaluronan (HA) shows promise for detecting cancerous change in pleural effusion and urine. However, there is uncertainty about the localization of HA in tumor tissue and its relationship with different histological types and other components of the extracellular matrix, such as angiogenesis. We evaluated the association between HA and degree of malignancy through expression in lung tumor tissue and sputum. Tumoral tissue had significantly increased HA compared to normal tissue. Strong HA staining intensity associated with cancer cells was significant in squamous cell carcinoma compared to adenocarcinoma and large cell carcinoma. A significant direct association was found between tumors with a high percentage of HA and MVD (microvessel density) in tumoral stroma. Similarly significant was the direct association between N1 tumors and high levels of HA in cancer cells. Cox multivariate analysis showed significant association between better survival and low HA. HA increased in sputum from lung cancer patients compared to cancer-free and healthy volunteers and a significant correlation was found between HA in sputum and HA in cancer tissue. Localization of HA in tumor tissue was related to malignancy and reflected in sputum, making this an emerging factor for an important diagnostic procedure in patients suspected to have lung cancer. Further study in additional patients in a randomized prospective trial is required to finalize these results and to validate our quantitative assessment of HA, as well as to couple it to gold standard sputum cytology.
Resumo:
Non-invasive markers of fibrosis have been used to diagnose liver fibrosis in a variety of diseases. Hyaluronic acid (HA) and collagen IV (C-IV) levels were measured in the sera of patients from an endemic area for schistosomiasis in Brazil to diagnose and to rank the intensity of liver fibrosis. Seventy-nine adult patients with schistosomiasis, in the age range of 21-82 years (49 ± 13.4) were submitted to clinical and ultrasonographic examinations. Ultrasound was employed to diagnose and categorise liver fibrosis according to World Health Organization patterns. Serum HA and C-IV levels were measured using commercial ELISA kits. Ultrasound revealed six patients with intense liver fibrosis, 21 with moderate, 23 with light and 29 without. Serum HA was able to separate individuals with fibrosis from those without (p < 0.001) and light from intense fibrosis (p = 0.029), but C-IV was not (p = 0.692). The HA diagnostic accuracy for fibrosis was 0.89. The 115.4 ng/mL cut-off level diagnosed patients with fibrosis (sensitivity 0.98, specificity 0.64). HA correlated positively with portal hypertension. Periportal fibrosis (subjective evaluation), age and collateral circulation predicted HA increase. In conclusion, we propose that serum HA can be used to identify patients with liver fibrosis in an endemic area for schistosomiasis mansoni in Brazil.
Resumo:
Hyaluronan is an important connective tissue glycosaminoglycan. Elevated hyaluronan biosynthesis is a common feature during tissue remodeling under both physiological and pathological conditions. Through its interactions with hyaladherins, hyaluronan affects several cellular functions such as cell migration and differentiation. The activities of hyaluronan-synthesizing and -degrading enzymes have been shown to be regulated in response to growth factors. During tumor progression hyaluronan stimulates tumor cell growth and invasiveness. Thus, elucidation of the molecular mechanisms which regulate the activities of hyaluronan-synthesizing and -degrading enzymes during tumor progression is highly desired.
Resumo:
Preparation for embryo implantation requires extensive adaptation of the uterine microenvironment. This process consists of cell proliferation and cell differentiation resulting in the transformation of endometrial fibroblasts into a new type of cell called decidual cell. In the present study, we followed the space-time distribution of versican and hyaluronan (HA) in different tissues of the uterus before and after embryo implantation. Fragments of mouse uteri obtained on the fourth, fifth, sixth and seventh days of pregnancy were fixed in Methacarn, embedded in Paraplast and cut into 5-µm thick sections. HA was detected using a biotinylated fragment of the proteoglycan aggrecan, which binds to this glycosaminoglycan with high affinity and specificity. Versican was detected by a polyclonal antibody. Both reactions were developed by peroxidase methods. Before embryo implantation, both HA and versican were present in the endometrial stroma. However, after embryo implantation, HA disappeared from the decidual region immediately surrounding the implantation chamber, whereas versican accumulated in the same region. The differences observed in the expression of HA and versican suggest that both molecules may participate in the process of endometrial decidualization and/or embryo implantation.
Resumo:
Hepatic fibrosis in patients with non-alcoholic fatty liver disease is associated with progression of the disease. In the present study, we analyzed the discriminative ability of serum laminin, type IV collagen and hyaluronan levels to predict the presence of fibrosis in these patients. In this preliminary report, we studied 30 overweight patients divided into two groups according to the absence (group I, N = 19) or presence (group II, N = 11) of fibrosis in a liver biopsy. Triglycerides, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltranspeptidade, hyaluronan (noncompetitive fluoroassay), type IV collagen, and laminin (ELISA) were determined. Group II presented significantly higher mean laminin, hyaluronan, type IV collagen, and aspartate aminotransferase values, which were due to the correlation between these parameters and the stage of fibrosis in the biopsy (Spearman's correlation coefficient, rS = 0.65, 0.62, 0.53, and 0.49, respectively). Analysis of the ROC curve showed that laminin values >282 ng/ml were those with the best diagnostic performance, with 87% accuracy. Association of laminin with type IV collagen showed improvement in the positive predictive value (100%), but with reduction in diagnostic sensitivity (64%). When compared with the criteria of Ratziu et al. [Gastroenterology (2000) 118: 1117-1123] for the diagnosis of septal fibrosis, laminin values presented a better diagnostic accuracy (83 vs 70%). Determination of extracellular matrix components in serum, especially of laminin, may identify patients with non-alcoholic fatty liver disease and fibrosis and these components may be used as indicators for liver biopsy in these patients.