Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10721 (c-kit)
 6,575 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Seminiferous tubules adjacent to germ cell tumors (GCT) in prepubertal boys frequently contain increased germ cells with abundant, clear cytoplasm. These cells are placental alkaline phosphatase (PLAP) negative and are usually not considered to represent intratubular germ cell neoplasia (ITGCN). A recent case report found p53 and proliferating cell nuclear antigen (PCNA) positivity in such cells and equated these PLAP-negative cells with ITGCN. Because the proto-oncogene c-kit is also a marker of ITGCN, immunohistochemical tests for c-kit and PLAP were performed on 28 testes adjacent to prepubertal GCT in children aged 2 to 45 months. Additional slides from testes not associated with GCT from 18 preterm infants and children ages 19 weeks to 7 years were also tested. An adult testis with seminoma and ITGCN served as a positive control. PCNA, PLAP, and p53 were tested on available slides. No intratubular germ cells adjacent to GCT in prepubertal children were positive for PLAP or c-kit; five of seven were positive for PCNA; p53 was present in the two examined. These results indicate that germ cells adjacent to infantile GCT are proliferative but not neoplastic and offer additional evidence that intratubular germ cells and GCT in prepubertal boys are different from those of adolescents and adults.
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PMID:The prepubertal testis (prenatal and postnatal): its relationship to intratubular germ cell neoplasia: a combined Pediatric Oncology Group and Children's Cancer Study Group. 910 38

Growth differentiation factor-9 (GDF-9), a secreted member of the transforming growth factor-beta superfamily, is expressed at high levels in the mammalian oocyte beginning at the type 3a primary follicle stage. We have previously demonstrated that GDF-9-deficient female mice are infertile because of an early block in folliculogenesis at the type 3b primary follicle stage. To address the molecular defects that result from the absence of GDF-9, we have analyzed the expression of several important ovarian marker genes. The major findings of our studies are as follows: 1) There are no detectable signals around GDF-9-deficient follicles for several theca cell layer markers [i.e. 17alpha-hydroxylase, LH receptor (LHR), and c-kit, the receptor for kit ligand]. This demonstrates that in the absence of GDF-9, the follicles are incompetent to emit a signal that recruits theca cell precursors to surround the follicle; 2) The primary follicles of GDF-9-deficient mice demonstrate an up-regulation of kit ligand and inhibin-alpha. This suggests that these two important secreted growth factors, expressed in the granulosa cells, may be directly regulated in a paracrine fashion by GDF-9. Up-regulation of kit ligand, via signaling through c-kit on the oocyte, may be directly involved in the increased size of GDF-9-deficient oocytes and the eventual demise of the oocyte; 3) After loss of the oocyte, the cells of the GDF-9-deficient follicles remain in a steroidogenic cluster that histologically resembles small corpora lutea. However, at the molecular level, these cells are positive for both luteal markers (e.g. LHR and P-450 side chain cleavage) and nonluteal markers (e.g. inhibin alpha and P-450 aromatase). This demonstrates that initially the presence of the oocyte prevents the expression of luteinized markers, but that the absence of GDF-9 at an early timepoint alters the differentiation program of the granulosa cells; and 4) As demonstrated by staining with either proliferating cell nuclear antigen (PCNA) or Ki-67 and TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) labeling, the granulosa cells of GDF-9-deficient type 3b primary follicles fail to proliferate but also fail to undergo cell death. This suggests that granulosa cells of type 3b follicles require GDF-9 for continued growth and also to become competent to undergo apoptosis, possibly through a differentiation event Thus, these studies have enlightened us as to the paracrine roles of GDF-9 as well as the normal steps of granulosa cell and theca cell growth and differentiation within ovarian follicles.
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PMID:Molecular characterization of the follicle defects in the growth differentiation factor 9-deficient ovary. 1037 99

To clarify the effect of hepatocyte growth factor (HGF) on proliferation of hepatic oval cells, we transferred HGF gene into liver of the Solt-Farber rat model. Male Fisher 344 rats were infected with a recombinant adenovirus carrying the cDNA for HGF (pAxCAHGF) from tail vein. HGF mRNA showed its peak at 4 days, and diminished thereafter. The total and proliferating cell nuclear antigen-positive hepatic oval cells were significantly elevated in HGF-transferred rats, in which stem cell factor and c-kit mRNA increased at each time point. Our results suggest that in vivo transfer of the HGF gene into liver accelerates proliferation of hepatic oval cells in the Solt-Farber model in rats.
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PMID:In vivo transfer of hepatocyte growth factor gene accelerates proliferation of hepatic oval cells in a 2-acetylaminofluorene/partial hepatectomy model in rats. 1074 90

In a 55-year-old man, a tumor about 3 cm in diameter was detected in the upper abdomen by abdominal ultrasound screening during follow-up of chronic hepatitis C discovered in 1990. There were no symptoms and no abnormalities on physical examination. Tests for tumor markers were negative. By barium meal and gastroscopy, submucosal tumor was found on the lesser curvature of the stomach, with bridging fold in the absence of central ulceration. Biopsy revealed no tumor tissue. Under the diagnosis of submucosal tumor of the stomach, either a leiomyoma or leiomyosarcoma, partial resection of stomach was performed. Direct invasion of the surrounding organs, lymph node metastasis or distant metastasis was not observed grossly in the operation. Histologic examination of the resected specimen revealed proliferation of spindle cells and oval cells in an interlacing pattern. Immunohistochemistry for CD34, vimentin and c-kit protein was strongly positive, while smooth muscle actin, S-100 protein, desmin and p53 protein were negative. The proliferating cell nuclear antigen index was about 50%, while the MIB-1 index was < or = 1%. From these findings, this tumor was diagnosed as a gastrointestinal stromal tumor of the uncommitted type.
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PMID:A case of gastrointestinal stromal tumor of the stomach. 1081 97

We determined the distribution of mast cells in nasal mucosa and studied their proliferation. Inferior turbinate mucosa was sampled in 13 patients with allergic rhinitis (allergic group) and 5 without (non allergic group) and stained immunohistochemically using anti mast cell tryptase antibody, anti-c-kit antibody, anti-PCNA antibody, and anti mast cell chymase antibody. Tissue sections stained with anti tryptase antibody revealed a higher degree of infiltration of tryptase-positive cells, i.e., mast cells, in the allergic group than in non allergic group. In the allergic group, the number of tryptase-positive cells, c-kit-positive cells, and PCNA-positive cells was significantly greater in the epithelium and shallow lamina propria than that in the deep lamina propria. Tryptase-positive, c-kit-positive cells, i.e., c-kit-positive mast cells, and tryptase-positive, PCNA-positive cells, i.e., PCNA-positive mast cells, were also abundunt in the epithelium and shallow lamina propria. The stem cell factor and c-kit receptor are reported to play a primary role in mast cell differentiation and proliferation. PCNA-positive cells represent actively proliferating cells. Based on the above, we concluded that mast cells in the epithelium and shallow lamina propria in the allergic group differentiated and proliferated more actively than those in the deep lamina propria.
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PMID:[Differentiation and proliferation of mast cells in nasal mucosa]. 1143 40

Reports of supernumerary ovaries are rare. We describe two such cases, one with fibroma and the other with endometriosis and cystic change. A large fibroma measuring 17.4 x 12.0 x 7.5 cm in size was found in the supernumerary ovary of the omentum in the first case of a 47-year-old married woman with Meig's syndrome. The second case was associated with endometriosis and cystic change, measuring 11 x 5 x 3 cm in size and located in the upper abdominal cavity. It was attached to the uterus of a 28-year-old pregnant woman who had neither fibroma nor Meig's syndrome. Histologically, corpus albicans and a few primordial germ cells were demonstrated, respectively. A fibroma showing a storiform pattern was found in the first case. The second case had endometriosis and a thin-walled cyst with bleeding and necrosis caused by torsion. Immunohistochemically, desmin, alpha-smooth muscle actin, c-kit, CA125, Na+/K+ATPase, overexpression of p53, myc and ras were all negative in the fibroma cells of the first case, and in the endometriosis and cyst wall of the second case. The fibroma cells were positive for vimentin and estrogen receptor, and the proliferating cell nuclear antigen was sporadically demonstrated in their nuclei. The mutation of the p53 gene at exons 5-8 was not detected by sequence analysis. Using RT-PCR, bax, bcl-2 and p16 were not detected either. Clinically, the two cases presented here did not show abnormal hormonal symptoms. They were diagnosed as abdominal tumors or masses. Based on these considerations, one might assume that supernumerary ovaries are probably more frequent than reported at present.
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PMID:Two cases of supernumerary ovary: one with large fibroma with Meig's syndrome and the other with endometriosis and cystic change. 1179 34

Through careful clinicopathologic correlation, we identified 37 metastatic melanomas in the skin, all of which had intraepidermal components. These were compared with 43 microscopically similar primary melanomas with a predetermined panel of immunostains in general use in surgical pathology, including bcl-2 protein, mutant p53 protein, Ki-67 (MIB-1), proliferating cell nuclear antigen (PCNA), alpha-isoform actin, and CD117 (c-kit protein). There was no significant difference in bcl-2 or alpha-isoform actin staining patterns of primary vs secondary cutaneous melanomas. The expression of Ki-67 generally was higher in metastatic melanomas than in primary lesions, and the same was true of mutant p53 protein labeling; however, some overlap was observed. CD117 staining was retained in 65% of metastatic melanomas (24/37) when they originated from ocular primary tumors; nevertheless, that marker was lost in virtually all of the other metastatic melanocytic neoplasms, whereas primary melanomas demonstrated consistent reactivity for c-kit protein. Although they are not definitive, these trends in immunoreactivity could facilitate the process of distinguishing the multiple primary melanoma syndrome from melanomatous metastases to the skin. That undertaking is best approached with circumspection, because clinicopathologic discriminators for this diagnostic separation are still imperfect.
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PMID:Primary melanoma of the skin and cutaneous melanomatous metastases: comparative histologic features and immunophenotypes. 1527 32

A germ-Sertoli cell coculture model was established to study effects of follicle-stimulating hormone (FSH) and testosterone (T) on testicular germ cell proliferation of the embryonic chickens. Germ and somatic cells were dispersed from 18-day-old embryonic testes and cultured in 96-well plates. Germ cells were characterized by expression of stem cell factor receptor c-kit. Germ cell proliferation was assessed by an increase in cell number and expression of proliferating cell nuclear antigen (PCNA). Results showed that the germ and Sertoli cells kept alive in serum-free McCoy's 5A medium supplemented with insulin, transferrin, and selenite (ITS medium). Germ cells adhered to the free surface of Sertoli cells that spread the filopodia and formed a monolayer in ITS medium. In the serum-containing medium, Sertoli cells displayed an increment with a flat squamous form and only a few very large germ cell masses were found in the free surface of Sertoli cells. Many germ cells showed apoptosis in the McCoy's 5A medium without ITS or serum. Only germ cells showed positive staining for c-kit in the coculture. Ovine FSH (0.25-1.0 IU/ml) significantly increased the number of germ cells, and PCNA-labeling index (P < 0.05). FSH also induced stronger c-kit expression compared with the control. In the FSH-treated groups, germ cells were manifested distinct knob-like form. Similar stimulating effect was found in the germ cell number by T treatments (10(-7)-10(-6)M). Furthermore, FSH (0.5 IU/ml) combined with T significantly promoted higher testicular germ cell proliferation (P < 0.05) compared with either FSH or T alone, which indicated that interaction of FSH and T might be additive. The above results showed that the serum-free germ-Sertoli cell coculture model allowed evaluating hormonal regulation of testicular germ cell proliferation. FSH and T promoted testicular germ cell proliferation probably through indirect effects on Sertoli cells.
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PMID:Effects of follicle-stimulating hormone and androgen on proliferation of cultured testicular germ cells of embryonic chickens. 1536 6

Male germ cell apoptosis has been extensively explored in rodents. In contrast, very little is known about the susceptibility of developing germ cells to apoptosis in response to busulfan treatment. Spontaneous apoptosis of germ cells is rarely observed in the adult mouse testis, but under the experimental conditions described here, busulfan-treated mice exhibited a marked increase in apoptosis and a decrease in testis weight. TdT-mediated dUTP-X nicked end labeling analysis indicates that at one week following busulfan treatment, apoptosis was confined mainly to spermatogonia, with lesser effects on spermatocytes. The percentage of apoptosis-positive tubules and the apoptotic cell index increased in a time-dependent manner. An immediate effect was observed in spermatogonia within one week of treatment, and in the following week, secondary effects were observed in spermatocytes. RT-PCR analysis showed that expression of the spermatogonia-specific markers c-kit and Stra 8 was reduced but that Gli I gene expression remained constant, which is indicative of primary apoptosis of differentiating type A spermatogonia. Three and four weeks after busulfan treatment, RAD51 and FasL expression decreased to nearly undetectable levels, indicating that meiotic spermatocytes and post-meiotic cells, respectively, were lost. The period of germ cell depletion did not coincide with increased p53 or Fas/FasL expression in the busulfan-treated testis, although p110Rb phosphorylation and PCNA expression were inhibited. These data suggest that increased depletion of male germ cells in the busulfan-treated mouse is mediated by loss of c-kit/SCF signaling but not by p53- or Fas/FasL-dependent mechanisms. Spermatogonial stem cells may be protected from cell death by modulating cell cycle signaling such that E2F-dependent protein expression, which is critical for G1 phase progression, is inhibited.
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PMID:Murine male germ cell apoptosis induced by busulfan treatment correlates with loss of c-kit-expression in a Fas/FasL- and p53-independent manner. 1538 31

The effects of follicle-stimulating hormone (FSH) and 17beta-estradiol (E2) on chicken ovarian germ cell proliferation were evaluated through a germ-somatic cell coculture model. Ovarian cells from the left ovaries of 18-day-old chicken embryos were cultured in serum-free McCoy's 5A medium at 39 degrees C and challenged with FSH (0.25-1.0 IU/mL) or E2 (10(-8)-10(-5) M) alone and in combination for 48 h. The number of germ cells was counted, and the proliferating cells were immunolocalized by a specific antibody against proliferating cell nuclear antigen (PCNA). The labeling index (LI) was determined for germ cells. Results revealed that germ cells could survive and kept proliferating under support of somatic cells. Germ cells were localized by expression of a specific antibody for stem cell factor receptor c-kit. Both FSH (0.25-1.0 IU/mL) and E2 (10(-7)-10(-5) M) alone induced a marked increase in germ cell number (P<0.05), and PCNA-LI of germ cells was greater in FSH-treated groups (0.25-1.0 IU/mL) and E2-treated groups (10(-8)-10(-5) M), compared with vehicle-treated group (P<0.05). Furthermore, FSH manifested a synergistic effect with E2 (10(-6)-10(-5) M) in stimulating germ cell proliferation. These results indicate that FSH might interact with estrogen to promote ovarian germ cell proliferation in embryonic chickens near hatching.
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PMID:Effects of follicle-stimulating hormone and 17beta-estradiol on proliferation of chicken embryonic ovarian germ cells in culture. 1559 98


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