Pathology Research and Practice 

About: Pathology Research and Practice is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Medicine & Cancer. It has an ISSN identifier of 0344-0338. Over the lifetime, 8520 publications have been published receiving 116073 citations.

Histopathology and classification of renal cell tumors (adenomas, oncocytomas and carcinomas). The basic cytological and histopathological elements and their use for diagnostics

Abstract: The term renal cell tumors (adenomas and carcinomas) subsumes the tumors deriving from the uriniferous tubule epithelium of the kidney. Precise analysis shows that the renal cell tumors display different cell types which build up the individual tumor alone or in combination with each other. Three categories of basic elements are distinguished in the characterization of renal cell tumors: Cytological elements = tumor cell types: Clear, chromophobe, chromophilic (basophilic, eosinophilic), oncocytic, spindle-shaped/pleomorphic. Histological elements = growth patterns: Compact, acinar (nest-like), tubulopapillary (tubular, papillary), cystic. Cytological grading of malignancy: G I, G II, G III; mainly based on the degrees of nuclear atypia. The cytological features are given priority compared to the histological growth forms for classification of renal cell tumors. However, the latter are not to be neglected in the overall evaluation of a tumor. A classification of renal cell tumors is suggested and the result of its application in 510 renal cell carcinomas and oncocytomas is presented. On this basis and in connection with the cytological grading, a more precise prognostic evaluation of the renal cell carcinomas is expected.

The androgen receptor in prostate cancer.

Abstract: The androgen receptor is a member of the family of nuclear receptors. In its activated form as an androgen receptor ligand complex (the ligand can either be testosterone or 5a-dihydrotestosterone), the androgen receptor is able to regulate a specific expression of target genes. The androgen receptor is expressed at high levels in male reproductive tissues. Mutations in the androgen receptor gene are the molecular cause of the androgen insensitivity syndrome, which is characterized by an aberrant male or an apparently female phenotype. Expansion of a CAG-repeat, encoding a polymorphic glutamine stretch is the cause of a rare motor neuron disease (Kennedy's disease). Hormonal therapy is the treatment of choice for metastatic prostate cancer. Hormone refractory prostate tumors in general still express androgen receptor. In a proportion of the late stage prostate tumors, somatic mutations in the androgen receptor gene have been described. Mutations can result in diminished ligand specificity of the androgen receptor. Furthermore, it has been hypothesized that ligand independent mechanisms can also be involved in androgen receptor activation.

Towards Understanding Skeletal Muscle Regeneration

Abstract: Factors which effect proliferation and fusion of muscle precursor cells have been studied extensively in tissue culture, although little is known about these events in vivo. This review assesses the tissue culture derived data with a view to understanding factors which may control the regeneration of mature skeletal muscle in vivo. The following topics are discussed in the light of recent developments in cell and molecular biology: 1) Injury and necrosis of mature skeletal muscle fibres 2) Phagocytosis of myofibre debris 3) Revascularisation of injured muscle 4) Activation and proliferation of muscle precursor cells (mpc) in vivo Identification of mpcs; Satellite cell relationships; Extracellular matrix; Growth factors; Hormones; Replication. 5) Differentiation and fusion of muscle precursor cells in vivo Differentiation; Fusion; Extracellular matrix; Cell surface molecules: Growth factors and prostaglandins 6) Myotubes and innervation.

WHO International Histological Classification of Tumours. Tentative Histological Classification of Salivary Gland Tumours.

Abstract: The principles of the proposed modified WHO Histological Typing of Salivary Gland Tumours are based on the following: 1) The classification of tumours is oriented to the routine work of the practicing surgical pathologists, those who do not see tumours of the salivary glands very often. The inclusion of rare, but clearly defined tumour entities should be helpful to surgical pathologists consulting with clinical specialists. 2) The different types of carcinomas must be distinguished not only by precise histopathological definitions, but also considering differences in prognosis and treatment. For example, the polymorphous low-grade adenocarcinoma and the epithelial-myoepithelial carcinoma are characterized by a relatively good prognosis in contrast to the salivary duct carcinoma. 3) Special points of discussion are: subclassification and grading of carcinomas (e.g. acinic cell carcinoma, mucoepidermoid carcinoma and adenoid cystic carcinoma), the classification of basal cell tumours (basal cell adenoma, basal cell carcinoma, solid type of adenoid cystic carcinoma), malignant tumours in pleomorphic adenomas and the differential diagnosis between primary tumours and metastases.

Nuclear Overexpression of the Oncoprotein β-Catenin in Colorectal Cancer is Localized Predominantly at the Invasion Front

Abstract: Sixty to eighty percent of all colorectal cancers are characterized by mutations in the APC tumor suppressor gene. Recently, it was shown that these mutations lead to a nuclear overexpression of beta-Catenin by disruption of the wingless/WNT signal pathway. Since nuclear beta-Catenin functions as a transcriptional activator of hitherto unknown tumor genes, this form of beta-Catenin is now considered a major oncoprotein in colorectal cancer. Using immunohistochemistry, we investigated the distribution of overexpressed beta-Catenin within individual colorectal carcinomas. In the majority of the tumors, we found no homogeneous staining, but a strong nuclear expression of beta-Catenin predominantly localized at the invasion front with strongest nuclear staining of isolated, scattered tumor cells. In contrast, cells in the tumor center often showed no nuclear staining, but retained a membranous expression of beta-Catenin, comparable to normal colon epithelium. It is, therefore, likely that in addition to the overexpression of beta-Catenin caused by defects in the APC locus, regulatory events in the tumor itself lead to a different distribution of this oncoprotein. Possibly, surrounding tissue at the invasion front can give signals to the tumor cells, leading to a nuclear translocation of beta-Catenin, where it may play a direct role in tumor invasion processes.