Hairy polyp of nasopharynx--a case report.
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A specific subtype of teratoid tumour occurring in nasopharynx and oropharynx has been mentioned as 'hairy polyp'. This is a rare lesion and is to be differentiated from true teratomas. A case of hairy polyp of nasopharynx in a 12 year old girl is reported. (+info)
A 20-day-old female neonate presented with an immature teratoma in the midline posterior fossa. The tumor was totally removed but the patient died of pneumonia. Teratoma is a rare tumor, but very difficult to treat as the patients tend to be young, and the outcome is very poor. (+info)
Inhibition of human endogenous retrovirus-K10 protease in cell-free and cell-based assays.
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A full-length and C-terminally truncated version of human endogenous retrovirus (HERV)-K10 protease were expressed in Escherichia coli and purified to homogeneity. Both versions of the protease efficiently processed HERV-K10 Gag polyprotein substrate. HERV-K10 Gag was also cleaved by human immunodeficiency virus, type 1 (HIV-1) protease, although at different sites. To identify compounds that could inhibit protein processing dependent on the HERV-K10 protease, a series of cyclic ureas that had previously been shown to inhibit HIV-1 protease was tested. Several symmetric bisamides acted as very potent inhibitors of both the truncated and full-length form of HERV-K10 protease, in subnanomolar or nanomolar range, respectively. One of the cyclic ureas, SD146, can inhibit the processing of in vitro translated HERV-K10 Gag polyprotein substrate by HERV-K10 protease. In addition, in virus-like particles isolated from the teratocarcinoma cell line NCCIT, there is significant accumulation of Gag and Gag-Pol precursors upon treatment with SD146, suggesting the compound efficiently blocks HERV-K Gag processing in cells. This is the first report of an inhibitor able to block cell-associated processing of Gag polypeptides of an endogenous retrovirus. (+info)
Multimodal treatment of malignant sacrococcygeal germ cell tumors: a prospective analysis of 66 patients of the German cooperative protocols MAKEI 83/86 and 89.
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PURPOSE: To evaluate a multimodal approach including surgery and cisplatinum chemotherapy for treatment of children with malignant sacrococcygeal germ cell tumors (GCT) and to compare adjuvant and neoadjuvant strategies in advanced tumors. PATIENTS AND METHODS: Between 1983 and 1995, 71 patients with malignant sacrococcygeal GCT were prospectively enrolled onto the German protocols for nontesticular GCT Maligne Keimzelltumoren 83/86 and 89. Five patients who received no chemotherapy (n = 2) or nonplatinum chemotherapy (n = 2) or who did not undergo tumor resection (n = 1) were excluded from this analysis. Among the 66 patients analyzed were 14 boys and 52 girls. The median age was 17.4 months (range, 7 months to 119 months). Median follow-up was 79 months (range, 4 months to 145 months). RESULTS: Fifty-two patients presented with locally advanced stage T2 tumors, and 30 patients had distant metastases at diagnosis. Patients received a median of eight cycles (range, four to nine cycles) of cisplatinum-based chemotherapy. Thirty-five patients underwent tumor resection at diagnosis and received adjuvant cisplatinum-based chemotherapy (group A). Thirty-one patients received up-front chemotherapy followed by delayed tumor resection (group B). Group B included more metastatic tumors than group A (group B, 19 of 31 patients; group A, 11 of 35 patients, P =.01). Preoperative chemotherapy facilitated complete tumor resections (group B, 20 of 31 patients; group A, five of 35 patients, P <.001) and avoided second-look surgery. Metastases at diagnosis and completeness of the first attempt of tumor resection were significant prognostic predictors; however, metastases were not predictive for patients treated with up-front chemotherapy. At 5 years follow-up, event-free survival was 0.76 +/- 0.05 (50 of 66 patients), and overall survival was 0.81 +/- 0.05 (54 of 66 patients). Four patients died as a result of therapy-related complications, and eight patients died of their tumors. Patients with locally advanced and metastatic tumors (T2b M1) fared better with neoadjuvant treatment [overall survival: 0.83 +/- 0.09 (16 of 19 patients) versus 0.45 +/- 0.15 (five of 11 patients), P =.01]. CONCLUSION: Even locally advanced and metastatic sacrococcygeal GCT can be successfully treated with up-front cisplatinum-based chemotherapy followed by delayed but complete tumor resection. (+info)
Heterogeneous vascular dependence of tumor cell populations.
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Cells within a tumor are highly heterogeneous with respect to a wide range of genotypic and phenotypic characteristics. The latter include such properties as growth, survival, invasion, and metastasis. We asked whether the degree to which individual tumor cells rely on a tumor's vasculature might also be heterogeneous. By adapting an intravital Hoechst 33342 staining technique, we labeled and isolated tumor cells based on their relative proximity to perfused vessels. Because tumor regions distal to the vasculature are likely hypoxic, we examined cells deficient for hypoxia-inducible factor-1alpha (HIF-1alpha), a transcription factor that has been shown to mediate hypoxia-induced responses, including apoptosis. Despite reduced vascularization in HIF-1alpha-/- embryonic stem cell-derived tumors, their growth in vivo was found to be accelerated relative to HIF-1alpha+/+ tumor counterparts. We hypothesized that this paradoxical observation is because of decreased apoptotic rate, resulting in diminished vascular dependence of HIF-1alpha-/- cells. Analysis of heterogeneous tumors established from mixtures of HIF-1alpha+/+ with HIF-1alpha-/- cells revealed that the proportion of cells expressing wild-type HIF-1alpha was increased in perivascular areas and decreased in distal tumor regions. Thus, cells expressing HIF-1alpha were found to be highly dependent on proximity to blood vessels for their growth and survival in vivo, whereas cells that had lost HIF-1alpha expression were much less so. Heterogeneity in angiogenesis dependence was also observed among cell subpopulations isolated from human melanoma xenografts. This potential for selection of less vascular-dependent tumor cell variants throughout the course of disease progression may have important implications for the long-term efficacy of anti-angiogenic therapy. (+info)
Fibroblast growth factor signaling and basement membrane assembly are connected during epithelial morphogenesis of the embryoid body.
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Fibroblast growth factors and receptors are intimately connected to the extracellular matrix by their affinity to heparan sulfate proteoglycans. They mediate multiple processes during embryonic development and adult life. In this study, embryonic stem cell-derived embryoid bodies were used to model fibroblast growth factor signaling during early epithelial morphogenesis. To avoid redundancy caused by multiple receptors, we employed a dominant negative mutation of Fgfr2. Mutant-derived embryoid bodies failed to form endoderm, ectoderm, and basement membrane and did not cavitate. However, in mixed cultures they displayed complete differentiation induced by extracellular products of the normal cell. Evidence will be presented here that at least one of these products is the basement membrane or factors connected to it. It will be shown that in the mutant, collagen IV and laminin-1 synthesis is coordinately suppressed. We will demonstrate that the basement membrane is required for embryoid body differentiation by rescuing columnar ectoderm differentiation and cavitation in the mutant by externally added basement membrane proteins. This treatment induced transcription of Eomesodermin, an early developmental gene, suggesting that purified basement membrane proteins can activate inherent developmental programs. Our results provide a new paradigm for the role of fibroblast growth factor signaling in basement membrane formation and epithelial differentiation. (+info)
Adrenal teratoma in four domestic ferrets (Mustela putorius furo).
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Teratomas are histologically complex neoplasms that are composed of structures derived from multiple germ cell layers (ectoderm, mesoderm, and endoderm). These neoplasms are uncommon in domestic animals and are usually found in the gonads. This paper describes teratomas of the adrenal gland in four domestic ferrets (Mustela putorius furo). Three of four of the neoplasms contained tissues from ectodermal, mesodermal, and endodermal germ cell layers; two of four contained rudimentary teeth. In one case, malignant epithelial cells had metastasized to local lymph nodes. Teratomas, although uncommon, should be included in the differential diagnosis for adrenal neoplasms in domestic ferrets. (+info)
The Filshie clip for laparoscopic adnexal surgery.
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BACKGROUND: Gynecologic endoscopic procedures are increasingly common and require the ability to control large vascular structures. METHOD: The Filshie clip is a silicone-lined, titanium occlusive device, originally designed and Food and Drug Administration (FDA) approved for surgical contraception. This device also has the potential for occluding vascular structures during laparoscopic surgery. EXPERIENCE AND RESULTS: We describe a salpingectomy, an excision of bilateral hydrosalpinges, and a salpingo-oopherectomy. We performed all procedures laparoscopically using this device as the primary modality for assuring hemostasis. CONCLUSION: The Filshie clip is a useful and economical device for assuring hemostasis during gynecologic endoscopic surgery. (+info)