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Biomedical subjects

B Gosselin

Publications and source records attributed to B Gosselin.

At least 19 recordsLinked to original sources
PubMed2003

[Localized amyloidosis of the cavum].

INTRODUCTION: Amyloidosis is characterized by extracellular deposits of proteins. OBSERVATION: A 66 year-old patient presented with a pseudo-tumoral amyloidosis of the cavum. Clinical and biological examinations confirmed the localized aspect of the disease and immunohistochemical exploration identified a type AL amyloidosis. COMMENTS: The disease may be diffuse involving many organs and leading to various clinical manifestations. It can also be localized and take on a pseudo-tumoral aspect. Localised amyloidosis is a rare lesion of the upper aero-digestive tract, predominating in the larynx. Nasopharyngeal involvement is exceptional.

Aged↗
PubMed2003

Minimal focus of adenocarcinoma on prostate biopsy: clinicopathological correlations.

AIMS: To establish the clinicopathological features of minimal volume prostate adenocarcinoma on prostate biopsy. METHODS: Twenty four cases of minimal adenocarcinoma diagnosed on prostate biopsy and treated by radical prostatectomy were reviewed. RESULTS: The major microscopic criteria were nuclear enlargement (22 of 24), infiltrative pattern (19 of 24), prominent nucleoli (19 of 24), intraluminal eosinophilic secretions (15 of 24), and high grade intraepithelial neoplasia associated (11 of 24). Sixteen of 24 cases were assigned a Gleason score 6 on biopsy. When the whole gland was assessed, 22 of these tumours were localised to the prostate (stage pT2), and only two cases were stage pT3. CONCLUSIONS: Minimal focus of adenocarcinoma on prostate biopsy is not an uncommon finding. It is usually an intermediate grade and localised stage neoplasm.

Adenocarcinoma↗
PubMed2002

Expression of human mucin genes in normal kidney and renal cell carcinoma.

AIMS: Human mucins are large O-glycoproteins expressed by epithelial cells. Mucins are thought to be implicated in cell protection, cell adhesion and signalling. The aim of this study was to investigate the expression of the human mucin genes (MUC1-4, 5AC, 5B, 6-7) in normal kidney and renal cell carcinoma. METHODS AND RESULTS: We analysed by in-situ hybridization, immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) the expression of these genes in normal adult kidney (n=14) and renal cell carcinomas (n=29). MUC1, MUC3 and MUC6 were expressed both in normal kidney and in renal carcinomas. In normal kidney, MUC1 was expressed in the distal convoluted tubules and in collecting ducts, whereas MUC3 was restricted to the proximal tubules. MUC4 was strongly expressed in epithelial urothelial cells of pyelocalyceal cavities. MUC6 was only detected by RT-PCR. In renal carcinoma, we showed a heterogeneous expression of MUC1 and MUC3 with an over-expression of MUC3 in renal clear cell carcinoma. The level of MUC3 expression by in-situ hybridization was associated with the nuclear grade in clear cell carcinoma. CONCLUSIONS: This study is the first large series investigating human mucin gene expression in the kidney. MUC1, MUC3 and MUC6 are expressed in normal and tumour kidney. The over-expression of MUC3 in renal cell carcinomas favours its implication in renal tumorigenesis.

Biomarkers, Tumor↗
PubMed2002

High frequency of a 30-bp deletion of Epstein-Barr virus latent membrane protein 1 gene in primary HIV non-Hodgkin's brain lymphomas.

A characteristic 30-base pair (bp) deletion (del) in the 3' end of the Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) gene, coding for the C-terminal NF-kappa B activation domain, has been identified in various lymphoproliferative disorders and nasopharyngeal carcinomas. In the single report to date of human immunodeficiency virus primary brain lymphomas (HIV-PBLs), del-LMP1 was noted in seven cases out of nine. The present study was designed to identify this deletion in a series of 31 diffuse large B-cell HIV-PBLs, with the aim of determining its possible oncogenic action. The presence of EBV was confirmed by EBER mRNA in situ hybridization. After genomic extraction from frozen tissue, two 20-base oligonucleotide primers flanking the site of the 30-bp deletion were used. DNA sequencing of the polymerase chain reaction (PCR) products confirmed an identical segment spanning 30-bp and 69-bp, frequently associated with mutational hotspots in 19 cases (61%). A role for del-LMP1 in the oncogenic potential of EBV in systemic proliferations is a matter of debate. Its high incidence suggests that the oncogenic mechanism of LMP1 in the brain might differ significantly from that in systemic lymphoid proliferations, and might be enhanced by HIV infection.

Adult↗
PubMed2001

Normal respiratory mucosa, precursor lesions and lung carcinomas: differential expression of human mucin genes.

Mucins are glycoproteins synthesized by epithelial cells and thought to promote tumor-cell invasion. Eight human mucin genes have been well characterized: MUC2, MUC5AC, MUC5B, MUC6 map to 11p15.5 and encode secretory gel forming mucins while MUC1, MUC3, MUC4, MUC7 are scattered on different chromosomes and encode membrane-bound or secreted mucins. The expression pattern of the mucin genes is complex in normal airways involving six genes, mainly MUC5AC and MUC5B in mucus-producing cells and MUC4 in a wide array of epithelial cells. MUC5AC overexpression in metaplasia, dysplasia and normal epithelium adjacent to squamous cell carcinoma provides additional arguments for a mucous cell origin of preneoplastic squamous lesions. MUC5AC and MUC5B expression is related to mucus formation in adenocarcinomas. Mucinous bronchioloalveolar carcinoma (BAC) has a particular pattern of mucin gene expression indicating that it has sustained a well-differentiated phenotype similar to the goblet cell, correlated with distinctive features i.e. a noninvasive pattern and a better prognosis than nonBACs. MUC4 is the earlier mucin gene expressed in the foregut, before epithelial differentiation and is expressed independently of mucus secretion both in normal adult airways and carcinomas. These findings are in favor the histogenetic theory of non-small-cell carcinoma originating from a pluripotent mucous cell.

Gene Expression Regulation↗
PubMed2001

Immunohistochemical detection of Fas and Fas ligand in sarcomatoid renal cell carcinoma.

Sarcomatoid renal cell carcinomas (SRC) are rare neoplasms associated with a very poor prognosis. The aim of this study was to evaluate biomarker expression and clinical significance in this uncommon renal cancer. Cytokeratin, epithelial membrane antigen, vimentin, desmin, smooth muscle actin, CD34, S-100 protein, MIB 1, p53, Fas and Fas ligand immunohistochemical expression was investigated in seven renal cell carcinomas with sarcomatoid changes. No significant difference between sarcomatoid and nonsarcomatoid areas was observed with the different biomarkers, excepted for Fas ligand. Fas expression was diffuse in sarcomatoid and nonsarcomatoid areas. However, Fas ligand had a higher expression in sarcomatoid in comparison to nonsarcomatoid areas. Our results showed that Fas and Fas ligand are both expressed in renal cancer. We suggest that the aggressive behavior of sarcomatoid carcinoma may be related to a higher expression of Fas ligand by tumor sarcomatoid cells. These findings may indicate that Fas ligand is a possible therapeutic molecular target for treatment of SRC.

Aged↗
PubMed2001

Mucinous bronchioloalveolar carcinomas display a specific pattern of mucin gene expression among primary lung adenocarcinomas.

Lung adenocarcinomas are heterogeneous clinically and histologically. Expression of the mucin genes was analyzed as a molecular marker of glandular cytodifferentiation in primary lung adenocarcinomas. Expression was correlated with histopathologic subtypes of World Health Organization classification with the aim of investigating the histogenesis of primary lung adenocarcinomas. Thirty-four primary lung adenocarcinomas were examined by in situ hybridization for mucin gene expression (MUC1-4, MUC5AC, MUC5B, MUC6-7) and by immunohistochemistry for MUC5AC and MUC5B apomucin expression. Mucinous bronchioloalveolar carcinoma (BAC) had a homogeneous pattern of mucin gene expression different from those of other types of lung adenocarcinoma, involving secreted mucins (MUC5AC, MUC5B, and MUC6) and membrane-bound mucins (MUC1, MUC3, and MUC4). Non-BAC adenocarcinoma and mucinous BAC aberrantly expressed mucin genes MUC3, and MUC3 and MUC6, respectively, which are undetectable in normal fetal and adult lung. Our results show the particular phenotype of mucin gene expression in mucinous type of BACs and the heterogeneous expression of respiratory and nonrespiratory mucins in the other types. This finding supports the theory of a common progenitor cell with the potential of multicellular differentiation. From a practical point of view, the aberrant expression of MUC3 and MUC6 could serve as a diagnostic marker in the management of the mucinous type of bronchioloalveolar carcinomas. HUM PATHOL 32:274-281.

Adenocarcinoma↗
PubMed2001

Bilateral renal oncocytosis with renal failure.

Oncocytosis is a term recently used to describe diffuse renal involvement by numerous oncocytic nodules. We report herein a case of a 53-year-old man with end-stage renal disease requiring hemodialysis. His kidneys were involved by numerous tumors. Histologic examination revealed more than 100 oncocytomas and an associated papillary renal cell carcinoma in the right kidney.

Adenoma, Oxyphilic↗
PubMed2001

[Medical demography: the portrait of pathologic anatomy and cytology].

Assessment of care supply in terms of medical labor force is difficult because of the disparity of available data. Using the medical specialty of pathology as an example, we present for the first time a demographic analysis based on the confrontation of main data sources. This study underlines some of the structural and dynamic problems which threaten the demographic stability of the specialty. The public service suffers from a lack of practitioners, especially in regional hospitals. Whereas one third of French pathologists work in the larger hospitals around Paris, in some other regions private services constitute the main component of the supply. Projections based on the aging phenomenon and a reduction in entry indicate a future problem in the renewal of generations of pathologists. The consequences of this programmed decrease in the number of French pathologists will be further exacerbated by the movement of the sex ratio in favor of women.

Demography↗
PubMed2001

[Malignant solitary fibrous tumor of pleura with focal expression of cytokeratin].

Solitary fibrous tumor is a rare circumscribed neoplasm involving usually the pleura and now described in many organs and in the soft tissues with a favorable outcome when completely excised. We report herein a malignant solitary fibrous tumor of the pleura occurring in a 59-year-old woman. The tumor cells strongly expressed vimentin and CD 34. In addition a weak positive staining was obtained using CD 99 and bcl 2. A disconcerting focal immunoreactivity with cytokeratin was observed. Solitary fibrous tumor is composed of loosely arranged spindle cells of variable density and may occasionally mimic malignant mesothelioma, an hemangiopericytoma or synovial sarcoma. Immunohistochemical study is helpful demonstrating a strong positivity for vimentin and CD 34 and absence of staining for epithelial markers and S-100 protein.

12E7 Antigen↗
PubMed2000

Enteroviruses can persist with or without active viral replication in cardiac tissue of patients with end-stage ischemic or dilated cardiomyopathy.

To investigate enterovirus replication versus persistence in end-stage cardiac diseases, endomyocardial biopsies from explanted hearts of 70 patients with idiopathic dilated cardiomyopathy (IDCM), 64 patients with chronic coronary disease (CCD), and 45 donors of healthy hearts (controls) were examined by reverse transcriptase-polymerase chain reaction for genomic and antigenomic enterovirus RNA and by VP1 antigen immunohistochemistry. Enterovirus genome was detected in 25 of 70 patients with IDCM and in 21 of 64 patients with CCDs (35.7 vs. 32.8%, respectively; P=.12). Of the 46 patients positive for genomic RNA, only 3 exhibited antigenomic RNA and VP1 antigen that demonstrated active viral replication, whereas 43 had latent infection characterized by the absence of antigenomic RNA associated with or not with VP1 antigen expression. No viral component was detected in control subjects. The findings demonstrate that a small percentage of patients with end-stage chronic cardiac diseases had active enterovirus replication in their myocardium.

Adult↗
PubMed2000

Negative immunohistochemical detection of CD103 (alphaEbeta7 integrin) in the infiltrates of acute rejection in liver and kidney transplantation.

BACKGROUND: The infiltration of epithelium by CD8+ T lymphocytes in human renal or liver allografts is a critical feature of acute rejection. CD103 expression can be acquired in vitro by CD8+ cytotoxic T lymphocytes in response to allogeneic renal epithelial cells and promotes their adhesion to epithelium and subsequent lysis of epithelial cells. We investigated the expression of CD103 in T-cell infiltrates during acute renal or liver rejection (grade < III). METHODS: Immunohistochemical detection of CD103 in 11 liver and 10 kidney transplant biopsies with histopathological diagnosis of acute rejection. RESULTS: None of the infiltrates expressed detectable CD103, although positive controls were stained under our conditions. CONCLUSIONS: Failure to detect CD103 in renal biopsies can be related to the early posttransplantation interval (<6 months) corresponding to a first rejection episode. In our hands, immunohistological detection of CD103 was not possible in the infiltrates of acute rejection in liver or kidney transplantation.

Acute Disease↗
PubMed2000

From normal respiratory mucosa to epidermoid carcinoma: expression of human mucin genes.

Mucous cells in the respiratory tract contribute to the maintenance of the normal epithelial cell population via mechanisms of cell proliferation and differentiation. Mucous cell hyperplasia often occurs as a basic response to injury in the tracheobronchial epithelium. These cells are also thought to be involved in the histogenesis of epidermoid metaplasia. A typical biochemical feature of these cells is mucus secretion. Aberrant glycosylation or under-glycosylation of mucins is well known in cancer; however, the specific role played by mucin genes is at present unclear. To provide information regarding the expression of these genes in squamous metaplasia and squamous cell carcinoma, we analyzed and compared the expression of MUC1-MUC7 genes by in situ hybridization in control respiratory mucosa and lesions associated with neoplasia (hyperplasia, metaplasia and dysplasia) and squamous cell carcinomas. MUC4 was expressed independently of mucus secretion since it was expressed weakly by basal cells and probably by ciliated cells as well as collecting ducts, epidermoid metaplasia with complete squamous cell differentiation, and most of epidermoid carcinomas even well differentiated and keratinized. In squamous metaplasia and dysplasia, MUC4 gene expression was diffuse and less intense than in normal epithelium. MUC5AC was overexpressed in dysplasia as well as in mucous cell and basal cell hyperplasia and undetectable when squamous differentiation was achieved.

Biomarkers, Tumor↗