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Same Tissue Sample (same + tissue_sample)

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Medical Sciences	100%

Selected Abstracts

Expression of melanoma-associated antigens in melanoma cell cultures

EXPERIMENTAL DERMATOLOGY, Issue 7 2005
Mirjana Urosevic
Abstract:, The efficiency of melanoma immunotherapy appears to depend on both melanoma- and immune system-specific factors. Melanoma-specific factors include melanoma-associated antigen (MAA) expression as well as HLA class I molecule expression. We investigated the expression of five MAA , Melan-A/MART-1, tyrosinase, gp100, MAGE-1 and MAGE-3 , by means of FACS analysis in 50 melanoma cell cultures and compared them to the cultures of human foreskin-derived melanocytes and melanoma cell line UKRV-Mel2. Melan-A, tyrosinase and gp100 expression was frequently reduced in melanoma cell cultures, compared to that in foreskin melanocytes, whereas MAGE-1 and MAGE-3 expression showed variable degree of upregulation, compared to that in foreskin melanocytes. The expression of all tested MAA demonstrated high interindividual variability. We further show that cell cultures derived from the same tissue sample are oligoclonal in nature, by demonstrating the presence of up to three cell populations bearing distinct MAA profile. Analysing samples derived from the same patient but each at a different time point, we show that MAA expression profile changes over time either in positive (increase) or in negative (decrease) direction. Finally, we demonstrate that brain metastasis-derived cell cultures significantly overexpress Melan-A and MAGE-3, compared to primary tumours and other metastatic sites (P -value range: 0.05,0.001). Elucidation of the MAA expression patterns and the kinetics within the same patient as well as during the course of the disease may help improve current and develop new immunotherapeutic strategies. [source]

Novel corrective equations for complete estimation of human tissue lipids after their partial destruction by perchloric acid pre-treatment: high-resolution 1H-NMR-based study

NMR IN BIOMEDICINE, Issue 2 2008
Niraj Kumar Srivastava
Abstract Owing to the small quantity of tissue available in human biopsy specimens, aqueous and lipid components often have to be determined in the same tissue sample. Perchloric acid (PCA) used for the extraction of aqueous metabolites has a deleterious effect on lipid components; the severity of the damage is not known. In this study, human muscle tissue was first treated with PCA to extract aqueous metabolites, and the residue was then used for lipid extraction by conventional methods, i.e. the methods of Folch and Bligh & Dyer and a standardised one using methanol/chloroform (1:3, v/v) used in our laboratory. A 1H-NMR spectrum was obtained for each lipid extract. Lipid was quantified by measuring the integral area of N+ -(CH3)3 signals of phospholipids (PLs). Triacylglycerol (TG) and cholesterol (CHOL) were quantified using the -CH2 - signals of glycerol and the C18 methyl signal, respectively. This study shows that prior use of PCA caused marked attenuation of TG, PL, and CHOL. This was confirmed by recovery experiments and observation of the direct effect of PCA on the standard lipid components. On the basis of the quantity of lipid lost in each case, three novel equations (with respect to TG, PL, and CHOL) were derived. Application of these equations to lipid quantities estimated in different pathological tissues after PCA pre-treatment produced values equivalent to those estimated without PCA use. This study conclusively shows that PCA pre-treatment damages all three lipid moieties, TG, PL, and CHOL. When PCA is used in a fixed ratio to the tissue, the lipid damage is also proportional and correctable by statistically derived equations. These equations will be useful in human biopsy specimens where aqueous and lipid components have to be studied using the same tissue sample because of the small quantity available. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Immunohistochemical expression of tumor antigens MAGE-A1, MAGE-A3/4, and NY-ESO-1 in cancerous and benign prostatic tissue

THE PROSTATE, Issue 1 2006
Tvrtko Hudolin
Abstract OBJECTIVE To investigate immunohistochemical expression of MAGE-A and NY-ESO-1/LAGE-1, cancer testis antigens in prostate tissues showing evidence of malignant transformation or benign hyperplasia. METHODS 112 prostate samples from patients undergoing surgery at the Urology Clinic at the Zagreb Clinical Hospital Center from 1995 to 2003 were investigated in this study. Of these, 92 carcinoma samples were obtained by radical prostatectomy, and 20 benign prostatic hyperplasia samples by transvesical prostatectomy. Three monoclonal antibodies were used for immunohistochemical staining: 77B for MAGE-A1, 57B for multi-MAGE-A and D8.38 for NY-ESO-1 expression. RESULTS Expression of MAGE-A1 was observed in 10.8% of carcinoma samples, whereas multi-MAGE-A and NY-ESO-1/LAGE-1 stained 85.9% and 84.8% of samples. Immunohistochemical staining was only detectable in the cytoplasm. A significant heterogeneity could be observed within a same tissue sample where areas with strong positivities coexisted with cancer testis antigens negative areas. Interestingly, a majority of 57B positive cases were also found to be D8.38 positive (correlation coefficient r,=,0.727 (P,<,0.01)). Cancer testis antigens expression was neither significantly correlated with PSA values nor with Gleason score. In benign prostatic hyperplasia tissues MAGE-A1 expression was detected in 5%, while 57B and D8.38 staining was observed in 15% samples, and in all cases percentages of positive cells were always <10%. CONCLUSION Our data underline the peculiar relevance of cancer testis antigens expression in prostate cancers, with potential implications regarding both diagnosis and therapy. © 2005 Wiley-Liss, Inc. [source]

Does imprint cytology of brain tumours improve intraoperative diagnoses?

ACTA NEUROLOGICA SCANDINAVICA, Issue 3 2003
T. Brommeland
Objectives , To evaluate the diagnostic accuracy using frozen sections only and a combination of imprint cytology and frozen sections. Material and methods , After introduction of imprint cytology as a supplement to frozen sections in 1999, 153 patients with brain tumours underwent stereotactic or open surgery. An equal number of cases prior to 1999 were chosen for comparison. Intraoperative diagnoses were compared with final diagnoses based on paraffin sections of the same tissue samples. The number of delayed intraoperative diagnoses was noted in each patient group. Results , The combined use of the two techniques improved intraoperative diagnostic accuracy from 87 to 91% while the delayed intraoperative diagnoses were significantly reduced from 30 to 8. The choice of surgical procedure did not affect the outcome of the pathological investigations. Conclusion , A combination of frozen sections and imprints significantly reduced the number of delayed intraoperative diagnoses. Intraoperative diagnostic accuracy was improved, although not to a statistically significant level. Choice of surgical procedure did not affect the diagnostic outcome. [source]