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Adjacent Fibroblasts (adjacent + fibroblast)
Selected AbstractsCyclooxygenase-2 expression in dermatofibroma and dermatofibrosarcoma protuberansJOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2008Neta Adler Background:, Dermatofibroma (DF) and dermatofibrosarcoma protuberans (DFSP) occasionally resemble each other histologically but differ in histogenesis and biological behavior. This study sought to determine if these lesions can be differentiated by the quantity or quality of expression of cyclooxygenase-2 (COX-2), an enzyme associated with both reactive and neoplastic processes. Patients and methods:, Formalin-fixed and paraffin-embedded samples from 20 DFs and 20 DFSPs were stained immunohistochemically with antibodies directed against COX-2. Staining was evaluated semiquantitatively for percentage and intensity using a three-tiered system. DFs were graded and analyzed by cellularity. Findings within the tumors were compared with fibrocyte staining in adjacent tissue. The results were analyzed. Results:, Nineteen DFs (95%) and 15 DFSPs (75%) were immunopositive for COX-2; this difference was not statistically significant. Highly cellular DFs showed more widespread (p = 0.0039; r = 0.614) and more intense (p = 0.0586; r = 0.429) staining than less cellular DFs and more prominent staining in adjacent fibroblasts (p = 0.044; r = 0.608). Conclusions:, COX-2 immunostaining does not distinguish DFs from DFSPs. However, the enzyme is expressed more widely and more intensely in more cellular, possibly younger, DFs. The prominent expression of COX-2 in DFSP may have clinical implications for treatment with COX-2 inhibitors in tumors that are not amenable to surgery. [source] The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of perio-dontitis in an animal modelJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2010L. Liu Liu L, Li C, Cai X, Xiang J, Cao Z, Dong W. The temporal expression and localization of extracellular matrix metalloproteinase inducer (EMMPRIN) during the development of periodontitis in an animal model. J Periodont Res 2010; 45: 541,549. © 2010 John Wiley & Sons A/S Background and Objective:, We previously demonstrated extracellular matrix metalloproteinase inducer (EMMPRIN) was associated with the matrix metalloproteinases production of human periodontitis. The aim of this study was to investigate the temporal expression and localization of EMMPRIN during ligature-induced periodontitis in rats. Material and Methods:, Periodontitis was inducd in rats by placing a thread around the cervix of the first mandibular molar. Animals were killed 3, 7, 11, 15 or 21 d after ligation. Mandibles were processed for paraffin sections and stained with hematoxylin and eosin or picrosirius red. The distance from the amelocemental junction to the alveolar crest (ACJ,AC) and the area fraction (Area%) of collagen fibers were measured. EMMPRIN was examined by immunohistochemistry and quantified by positive cell counting. Correlation analyses were then performed. Results:, Histologically, alveolar bone was gradually destroyed from day 3 to 11 and then stabilized. Collagen fibers were slightly dissociated on day 3 and extensively broken on day 7. They were reconstructed from day 11 to 21. EMMPRIN was localized predominantly in infiltrating cells and adjacent fibroblasts in interdental gingiva. The number of EMMPRIN-positive cells increased on day 3, peaked on day 7 and then gradually subsided from day 11 to 21. Statistically, there was a moderate positive correlation regarding the ACJ,AC distance (r = 0.552, p < 0.01) and a strong negative correlation with the Area% of collagen fibers (r = ,0.808, p < 0.01). In gingival epithelium, the immunoreactivity was extremely strong in basal layer cells and sulcular epithelial cells in health. It was greatly enhanced in the inflamed conditions on days 3 and 7. In the interradicular bone, EMMPRIN was localized in the osteoclasts on days 3 and 7, as well as in the osteoblasts from day 11 onwards. Conclusion:, The expression and localization of EMMPRIN are temporally varied during the development of periodontitis. In addition, the inflammation-dependent expression of EMMPRIN might be involved in alveolar bone resorption and collagen breakdown. [source] Role of axon-deprived Schwann cells in perineurial regeneration in the rat sciatic nerveNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2000M. Popovi The role of Schwann cells (SC) in perineurial regeneration after nerve injury has not yet been resolved. It was hypothesized that SC alone are able to induce at least partial morphological restoration of the destroyed orthotopic perineureum (PN). To test the hypothesis, a permanently denervated segment of the rat sciatic nerve was made acellular by freeze-thawing, except in its most proximal part where non-neuronal cells were left intact. Restoration of the frozen segment by these cells was examined by electron microscopy and immunohistochemistry of the SC marker, S-100 protein, 4 and 8 weeks after injury. The PN regenerated from undifferentiated fibroblast-like cells. In the presence of migrant SC without axons, regenerated cells in the place of the former PN were stacked in several layers and, in accordance with the hypothesis, partially expressed typical features of the perineurial cells (PC): pinocytotic vesicles, short fragments of basal lamina and tight junctions. Migrant SC induced formation of pseudo-minifascicles even in the epineurium. In these, SC organized the adjacent fibroblasts into a multilayered circular sheath, and induced their partial differentiation towards perineurial cells. Further experiments demonstrated that regenerating axons are required for complete morphological differentiation of the regenerated perineurial cells either in the orthotopic PN or in minifascicles. [source] Emmprin (basigin/CD147): Matrix metalloproteinase modulator and multifunctional cell recognition molecule that plays a critical role in cancer progressionPATHOLOGY INTERNATIONAL, Issue 7 2006Kazuki Nabeshima Emmprin (basigin, CD147) is a cell surface glycoprotein that belongs to the immunoglobulin superfamily. It is highly expressed on the surface of tumor cells and stimulates adjacent fibroblasts or tumor cells to produce matrix metalloproteinases. Moreover, it has recently been shown that emmprin also stimulates expression of vascular endothelial growth factor and hyaluronan, which leads to angiogenesis and anchorage-independent growth/multidrug resistance, respectively. These findings have made emmprin an important molecule in tumor progression and, thus, more attractive as a target for antitumor treatment. However, other functions of emmprin, including as an activator of T cells, a chaperone for monocarboxylate transporters, a receptor for cyclophilin A and a neural recognition molecule, are also being identified in physiological and pathological conditions. Therefore, it is essential to develop specific means to control particular functions of emmprin, for which elucidation of each mechanism is crucial. This review will discuss the role of emmprin in tumor progression and recent advances in the molecular mechanisms of diverse phenomena regulated by emmprin. [source] Overexpression of keratinocyte growth factor in cancer cells and enterochromaffin cells in human colorectal cancerPATHOLOGY INTERNATIONAL, Issue 5 2000Masanori Watanabe Keratinocyte growth factor (KGF) is a mitogenic polypeptide that is mainly synthesized by mesenchymal cells. Its actions are dependent on its binding to a specific cell-surface KGF receptor (KGFR), which is localized in epithelial cells. In the present study, the expression level of KGF and KGFR messenger RNA (mRNA), and the localization of these mRNA and proteins in tumor specimens obtained from 12 human colorectal cancer cases were estimated. Competitive reverse transcriptase,polymerase chain reaction (RT-PCR) revealed the expression of KGF and KGFR mRNA in both colorectal cancer and normal colorectal tissues. In specimens from 10 of the 12 cancer cases, the KGF mRNA level was higher in the specimens obtained from the cancerous portions than in those obtained from non-cancerous tissues of the same cases. KGFR mRNA was higher in cancerous tissues in eight of 12 cases. To localize the KGF protein in normal and cancerous human colorectal tissues, immunohistochemistry was employed. In normal colorectal tissue, faint KGF immunoreactivity was present in a few fibroblasts. In contrast, strong KGF immunoreactivity was present in many of the neuroendocrine cells present in close proximity to cancer cells, and moderate immunoreactivity was recognized in the cancer cells themselves and adjacent fibroblasts. KGF-positive neuroendocrine cells also showed serotonin immunoreactivity, indicating that they were enterochromaffin cells. By in situ hybridization, both KGF and KGFR mRNA were co-overexpressed in these colorectal cancer cells, and KGF mRNA was recognized in neuroendocrine cells lying in close proximity to the cancer cells. These findings indicate the possibility that KGF acts in both a paracrine and autocrine manner to induce colorectal cancer cell growth in vivo. [source] | ||||||||||