Induction of neurogenic tumors in C3HeB-FeJ mice by nitrosourea derivatives: observations by light microscopy, tissue culture, and electron microscopy.
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The human oral and gut microbiota are the 4 largest microbial communities in the body and play crucial roles in maintaining homeostasis and influencing disease. Observational studies have suggested links between these microbiota and bone neoplasm-related phenotypes, but establishing causality has been challenging due to confounding factors and reverse causality. We conducted a bidirectional, 2-sample Mendelian randomization (MR) study to investigate evidence consistent with a potential causal association between the saliva and gut microbiota and various bone neoplasm-related phenotypes. Genetic instruments for saliva and gut microbiota were sourced from large genome-wide association studies. Inverse variance weighted was the primary MR method, supplemented by 4 other MR techniques. Sensitivity analyses, including MR-Egger regression, were performed to assess pleiotropy and heterogeneity. In the forward MR analysis, Veillonella parvula from the saliva microbiota was associated with a decreased risk of bone and connective tissue neoplasms (β: -0.236, 95% CI: [-0.275, -0.197], P = 8.20E-33). MR analyses identified genetically predicted associations between several microbial taxa and bone neoplasm-related phenotypes. Reverse MR analyses showed that genetic liability to bone neoplasm-related phenotypes was associated with variation in the composition of the oral (e.g., Order Bacteroidales, Rothia mucilaginosa) and gut microbiota (e.g., Class Methanobacteria, Genus Eubacterium oxidoreducens group). Sensitivity analyses confirmed the robustness of these findings, as no statistical evidence of substantial heterogeneity or directional horizontal pleiotropy was detected. This study provides genetic evidence supporting a bidirectional causal relationship between specific saliva and gut microbiota and bone neoplasm-related phenotypes. Our findings identify several microbial taxa as potential candidates for future biomarker development and therapeutic investigation in bone neoplasm-related phenotypes. However, these genetically informed associations require further mechanistic, experimental, and prospective clinical validation before clinical application.
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This is a classification of tumours of fibrous tissue, fat, muscle, blood and lymph vessels, and mast cells, irrespective of the region of the body in which they arise. Tumours of fibrous tissue are divided into fibroma, fibrosarcoma (including "canine haemangiopericytoma"), other sarcomas, equine sarcoid, and various tumour-like lesions. The histological appearance of the tumours is described and illustrated with photographs.
This article is a survey of actual aspects. With regard to frequency, the malignant fibrous histocytoma comes first, followed by lipo- and fibrosarcoma, synovial sarcoma, malignant schwannoma, malignant tumours proceeding from arteries and veins and the unstriated musculature. Staging and grading of these tumours are difficult. Until now their overall TNM-classification was not possible due to insufficient hard criteria.
Immunohistological demonstration of cell- and tissue-specific antigens in microscopic slides has remarkably influenced the classification of certain cutaneous neoplasms. The following markers are of particular interest in dermatopathology: cell surface antigens of lymphocyte subpopulations, intracytoplasmic immunoglobulins, intermediate filaments, neural markers, epithelial cell membrane antigens, and endothelial products. During the last years, these methods have contributed to our understanding of histogenesis and classification especially of cutaneous lymphomas, epithelial neoplasms, neurogenic tumors, and angiosarcomas.
The diagnosis and classification of soft tissue sarcomas can pose difficult problems for the histopathologist. Many sarcomas are too poorly differentiated to exhibit morphological features specific enough to define their histogenesis. Using the immunoperoxidase technique with commercially available antisera as a routine adjunct to other diagnostic aids, it is possible to arrive at more accurate diagnoses on which treatment protocols can be based. In addition a better understanding of mesenchymal neoplasms and their origins can be obtained by functional immunohistochemical studies.
Desmoid fibromatosis is a locally aggressive proliferative soft tissue lesion of controversial nature. The authors investigated the clonality of this process by molecular genetic analysis of DNA methylation pattern at a polymorphic site at the human androgen-receptor gene (HUMARA) to examine the inactivation pattern of the X chromosome. Twenty desmoid fibromatoses including primary and recurrent lesions from 11 female patients were studied. Sixteen lesions from eight patients showed nonrandom X inactivation, consistent with a clonal origin and, therefore, a true neoplastic nature. Furthermore, multiple recurrent lesions from two patients exhibited the same inactivation pattern as the corresponding primary lesions, suggesting that they were derived from the same cell clone as the primary lesion. One patient was homozygous at the HUMARA locus, and two patients had the same skewed pattern in their normal and lesional tissues. The authors also found that digestion with HpaII, but not HhaI, failed to generate a nonrandom X inactivation pattern in some of the cases, suggesting that the methylation status at the HpaII sites was altered in some lesions, and that HhaI should be used to verify results and to avoid incorrect conclusions.
The expression of the CD10 antigen, formerly designated as common acute lymphoblastic leukemia antigen and recently identified as neutral endopeptidase, was examined immunohistochemically in 26 benign and in 55 malignant mesenchymal tumors. CD10 expression was found in 4 of 4 leiomyomas, 7 of 10 leiomyosarcomas, 1 of 6 rhabdomyosarcomas, 2 of 2 Triton tumors, 1 of 2 aggressive fibromatoses, 1 of 3 fibrosarcomas, 1 of 4 synovial sarcomas, 1 of 1 giant cell tumors of tendon sheath, 4 of 4 malignant fibrous histiocytomas, 3 of 3 Ewing's sarcomas, and 2 of 3 osteosarcomas. Furthermore, CD10 was expressed consistently in the myoepithelial compartment of 12 fibroadenomas and, in 7 of these cases, in a minor stromal cell population, probably of (myo-) fibroblastic origin. Tumors of adipose tissue (4 lipomas, 5 liposarcomas), tumors of autonomic ganglia (2 ganglioneuromas, 1 ganglioneuroblastoma, 2 neuroblastomas), tumors of peripheral nerves with purely schwannian differentiation (7 malignant schwannomas), and tumors of disputed origin were consistently CD10-negative, however, as were single cases of fibroma and chondrosarcoma. These findings indicate that the expression of CD10 is a frequent but not obligatory feature in some mesenchymal tumors. Therefore CD10 is of value in the differential diagnosis of mesenchymal tumors.
A wide variety of benign tumors present in the oral cavity. These tumors are for the most part rare and are classified by the tissue of origin. Although benign oral cavity tumors are not life-threatening, they can result in extensive loss of soft tissue and/or bone. Furthermore, many patients are subject to the threat of recurrence, multiple surgical procedures, and the possibility of malignant degeneration. Because many tumors vary little clinically, an adequate biopsy specimen must be obtained for diagnosis. Radiographs are, in general, nondiagnostic. Collaboration with an experienced pathologist is necessary to determine the tumor's probable clinical behavior. Therapy, which is dictated by tumor type, is almost always surgical.
The Manchester Children's Tumour Registry data for the period 1954-1977 have been analysed. The overall incidence of malignant disease in children aged 0-14 years in the north-west of England is estimated to be 100 per million person-years. The most common disease group is leukaemia, which forms about one third of the total number of cases. Among solid tumours, by far the most common presenting site is the central nervous system, representing nearly a quarter of all neoplasms. Wilms' tumour, neuroblastoma and soft-tissue sarcomas comprise approximately 5%, 6.5% and 6% respectively of the total. The tumours most frequently seen in adults (e.g. carcinoma of colon, lung and breast) are extremely rare in childhood. A significant excess of males was seen in acute lymphoid leukaemia, non-Hodgkin's lymphoma, Hodgkin's disease, medulloblastoma and hepatoblastoma. A female excess was found among germ-cell tumours. During the study period significant increases in incidence were seen among acute lymphoid leukaemia and epithelial tumours, and an increase in germ cell tumours approached significance.
The alterations in specific activity and/or isozyme pattern of hexokinase, phosphofructokinase, aldolase, enolase, pyruvate kinase and glucose-6-phosphate dehydrogenase were studied in the tissue specimens of 26 patients with lipoblastic tumors and 28 patients with tumors of neurogenic origin. Although the biochemical data demonstrated that the activities of most enzymes studied were elevated in the specimens of the malignant tumors, only the differences in activity of hexokinase, pyruvate kinase and glucose-6-phosphate dehydrogenase measured between benign and malignant neurogenic tumors were significant. In malignant tumors, especially those of neurogenic origin, the isozyme pattern of pyruvate kinase showed a shift towards K-type subunits.
Soft tissue malignancies often show divergent differentiation, including myogenic lineage. Five rat tumors induced with 20-hydroxymethylcholanthrene (20-OH-MCA), were cultured in vitro, and three cell lines (YMC-1, YMC-2, YMC-3) were established from them. YMC-2 and -3 cells were spindle-shaped, and YMS-1 cells round and epithelioid. In confluency, YMC-3 cells formed myotubes. The nude mouse xenotransplants showed morphological features consistent with their myogenic phenotypes. Muscle-specific enzyme activities were highest in YMC-3 cells. These lines may be useful in the investigation of the myogenic differentiation of undifferentiated mesenchymal cells.
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