Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The number of mast cells is increased in dermatofibroma lesions and plays a role in the induction of fibrosis or its proliferation. We have investigated stem cell factor expression in solitary and multiple dermatofibromas by immunohistochemical straining. We also analyzed messenger RNA (mRNA) expression of stem cell factor in dermatofibroma tissues and cultured fibroblasts derived from dermatofibromas, using reverse transcriptase polymerase chain reaction. We found immunoreactive stem cell factor in keratinocytes, dermal fibroblasts, melanocytes and hair follicles. Unexpectedly, a reduced expression of immunoreactive stem cell factor in dermatofibroma fibroblasts was observed in solitary and multiple type. However, mRNA expression of stem cell factor was detected both in the dermatofibroma tissue and cultured dermatofibroma-derived fibroblasts. We speculate that the altered expression of stem cell factor of tumor cells in dermatofibroma lesions can be associated with the tumor cell proliferation and induction of dermatofibroma.
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PMID:Impaired expression of stem cell factor in dermatofibroma fibroblasts. 886 78

Dermatofibroma (DF) is histologically characterized by proliferation of fibroblasts in the dermis. Multiple DFs occasionally develop in patients with autoimmune disorders under immunosuppressive therapy; however, the pathogenesis of DF is still unclear. To elucidate immunological involvement in the mechanism of the fibrosis in DF, we studied the role of interleukin-1 (IL-1), which has a number of biological functions, including proliferation and collagen production of fibroblasts, on DF-derived fibroblasts. 3H-thymidine incorporation was used to examine the effects of Il-1 alpha and IL-1 beta in 4 cultured fibroblast strains derived from DF and 5 fibroblast strains from normal skin. Expression of mRNA of IL-1 was also analyzed by reverse transcriptase polymerase chain reaction (RT-PCR). Basal 3H-TdR incorporation without stimulant of DF-derived fibroblasts showed a significantly greater growth activity than normal skin-derived fibroblasts (2, 632 +/- 525 vs. 762 +/- 144 dpm, p < 0.01). Both IL-1 alpha and IL-1 beta showed a stronger growth-stimulatory activity on DF-derived fibroblasts in a dose-dependent manner than normal fibroblasts, and the percent 3H-TdR uptake of DF was 1.4-fold (IL-1 alpha; 1,000 U/ml) and 1.3-fold (IL-1 beta; 1,000 U/ml) as compared with normal fibroblasts; however, the differences did not reach any significance. When increasing concentrations of IL-1 receptor antagonist (IL-1 alpha) were added to culture medium stimulated with IL-1 alpha, the proliferative response of fibroblasts was significantly reduced. Expression of IL-1 beta and RNA was detected on both DF-derived and normal skin-derived fibroblasts, while that of IL-1 alpha mRNA was detected only on DF-derived fibroblasts. Our results suggest that IL-1 may be involved in the fibrotic process in DF at the transcriptional level and play a role in the fibroblast proliferation in an autocrine manner.
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PMID:Possible involvement of interleukin-1 in the pathogenesis of dermatofibroma. 953 85

Indeterminate fibrohistiocytic lesions of the skin share histological and immunohistochemical features of both benign fibrous histiocytoma/dermatofibroma and dermatofibrosarcoma protuberans (DFSP). Unlike dermatofibroma, DFSP harbors recurrent genetic aberrations resulting in the fusion of COL1A1 on chromosome 17 and PDGFB on chromosome 22. Because indeterminate fibrohistiocytic lesions share some features with DFSP, they were evaluated for the possible presence of COL1A1-PDGFB chimeric transcripts. Twelve formalin-fixed paraffin-embedded cases were examined for COL1A1-PDGFB chimeric transcripts using a previously validated sensitive multiplex reverse transcriptase-polymerase chain reaction assay. The median patient age was 52.5 years (33-70 years) with 9 females and 3 males. The most common site was the extremities (n = 8) followed by the trunk (n = 2) and the head and neck region (n = 2). All demonstrated the expected reactivity for both CD34 and factor XIIIa, and the majority focally infiltrated into subcutaneous fat. Of the 6 patients with follow-up, 2 had residual tumor excised, but no patient developed a recurrence. None of the tumors harbored COL1A1-PDGFB fusion transcripts identified by reverse transcriptase-polymerase chain reaction. Although indeterminate fibrohistiocytic lesions share some features with DFSP, the lack of COL1A1-PDGFB chimeric transcripts suggests that they are distinct entities.
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PMID:COL1A1:PDGFB chimeric transcripts are not present in indeterminate fibrohistiocytic lesions of the skin. 1994 Jul 48