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We have previously shown that osteosarcomas (OS) have states of increased interstitial fluid pressure (IFP), which correlate with increased proliferation and chemosensitivity. In this study, we hypothesized that constitutively raised IFP in OS regulates angiogenesis. Sixteen patients with the clinical diagnosis of OS underwent blood flow and IFP readings by the wick-in-needle method at the time and location of open biopsy. Vascularity was determined by capillary density in the biopsy specimens. We performed digital image analysis of immunohistochemical staining for CD31, VEGF-A, VEGF-C, and TPA on paraffin-embedded tissue blocks of the biopsy samples. Clinical results were validated in a pressurized cell culture system. Interstitial fluid pressures in the tumors (mean 33.5 ± SD 17.2 mmHg) were significantly higher ( p = 0.00001) than that in normal tissue (2.9 ± 5.7 mmHg). Pressure readings were significantly higher in low vascularity tumors compared to high vascularity tumors ( p < 0.001). In the OS cell lines, growth in a pressurized environment was associated with VEGF-A downregulation, VEGF-C upregulation, and TPA upregulation. The reverse was seen in the OB cell line. Growth in the HUVEC cell line was not significantly inhibited in a pressurized environment. Immunohistochemical assessment for VEGF-A ( p = 0.01), VEGF-C ( p = 0.008), and TPA ( p = 0.0001) translation were consistent with the findings on PCR. Our data suggests that some molecules in angiogenesis are regulated by changes in IFP. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:1520-1525, 2008 [ABSTRACT FROM AUTHOR]

Investigates the prevalence of the MYC gene amplification in pagetic osteosarcomas. Amplification assessed by Southern blot analysis using frozen tissue samples in five cases of pagetic osteosarcoma; Incidence of MYC amplification; Indications that four pagetic osteosarcomas were shown to be immunoreactive to P53.

The purpose of this review was to determine whether imatinib mesylate (STI571, Gleevec) has a role in the treatment of osteosarcoma. The expression of platelet-derived growth factor (PDGF) receptor and its ligand was examined in a panel of surgical specimens obtained from 54 osteosarcoma patients, and then the expression was compared with prognosis. The effects of imatinib mesylate on growth and molecular events in 10 patient-derived osteosarcoma cell cultures were investigated. Immunohistochemical studies demonstrated frequent expression of PDGF-AA (80.4%) and PDGF-alpha receptor (79.6%) and their correlation with inferior event-free survival (P < .05). PDGF-B-B and PDGF-beta-receptor expressions were also frequent (75.4% and 86%, respectively); however, statistically significant inferior event-free survival was not demonstrated (P = .15). In vitro studies demonstrated that imatinib mesylate had a variable cytotoxic effect on various osteosarcoma primary cultures, with an IC(50) of 5.6 microM to 9.5 microM, and blocked the PDGF-induced intracellular signal transduction as well as inhibition of downstream Akt phosphorylation. Mitogen-activated protein kinase (MAPK) was constitutively activated despite PDGF stimulation and imatinib mesylate treatment in 7 of 10 osteosarcoma cultures, perhaps explaining uncontrolled proliferation and relative unresponsiveness to imatinib. Imatinib mesylate could not be viewed as having a role as a single agent at current conventional doses for the treatment of osteosarcoma. These findings predicted activity in osteosarcoma clinical trials and suggested that in vitro model systems predict clinical behavior and that PDGF and its receptor expression could potentially be used for determining prognosis of osteosarcoma. [ABSTRACT FROM AUTHOR]

We report the case of a 41-year-old woman who presented with ipsilateral synchronous low-grade juxtacortical osteogenic sarcoma of the distal femur and low-grade intramedullary osteogenic sarcoma of the proximal tibia. The diagnosis and treatment and a review of the literature also are provided. [ABSTRACT FROM AUTHOR]

As primary bone fibrosarcoma (FS) and malignant fibrous histiocytoma (MFH) have similar clinical, radiographic, or survival manifestations, ultrastructural and immunohistochemical studies were undertaken to determine the differentiation pathways of constituent malignant cells. Twelve cases of primary intraosseous FS and MFH were selected for this ultrastructural comparative study and were analyzed for fibroblastic or modified fibroblastic differentiation. There were 4 FS cases and 8 MFH cases, of which 5 were storiform-pleomorphic, 2 were giant cell, and 1 was myxoid type. All FS consisted of spindle fibroblasts with a prominent rough endoplasmic reticulum and Golgi apparatus, variable amounts of vimentin intermediate filaments, and extracellular collagen fibrils. The MFH were composed of a mixture of spindle and pleomorphic fibroblasts (8/8), histiofibroblasts (4/8), and myofibroblasts (3/8). Variable numbers of undifferentiated cells were found in both tumors. In conclusion, fibroblastic differentiation and collagen production was noted in all cases. The often pleomorphic histiofibroblasts present in some MFH cases most likely represent "modified fibroblasts," similar to myofibroblasts. These findings support the hypothesis that the fibroblast and its variants are the predominant cell types found in these tumors, suggesting that the diagnostic entity MFH should be classified as a pleomorphic fibrosarcoma. [ABSTRACT FROM AUTHOR]

The article describes the case of a patient with a painful intraosseous leiomyoma involving the distal aspect of the ulna. Leiomyomas are benign smooth-muscle tumors that most commonly arise in the uterus, the gastrointestinal tract, and the skin. Leiomyomas are infrequently seen in the extremities and are rarely seen in bone. Leiomyomas of bone can present with pain and radiographic evidence of an expansile, sometimes lytic lesion. Marginal excision is typically curative, and recurrences are uncommon.

Fanconi anemia is an autosomal recessive disorder characterized by congenital malformations, bone marrow failure, and the development of squamous cell carcinomas (SCCs) and other cancers. Recent clinicopathologic evidence has raised the possibility that an environmental factor such as human papillomavirus (HPV) may be involved in the pathogenesis of SCCs in Fanconi anemia patients. Given the high prevalence of p53 mutations in SCCs among the general population and the lack of p53 mutations in HPV-related carcinogenesis, we evaluated the role of HPV and p53 mutations and polymorphisms in SCC from Fanconi anemia patients. We used polymerase chain reaction (PCR) screening and real-time PCR to detect and quantify HPV DNA in DNA extracted from microdissected SCCs obtained from 24 Fanconi anemia patients (n = 25 SCCs; case subjects) and 50 age-, sex-, and tumor site-matched SCC patients without Fanconi anemia (n = 50 SCCs; control subjects). We PCR-amplified and sequenced exons 4-9 of the p53 gene from SCC DNA. We detected HPV DNA in 84% of the SCC specimens from the case subjects and in 36% of the SCC specimens from the control subjects (P<.001). The prevalence of p53 mutations in SCCs from the case subjects (0%, 0/25) was statistically significantly lower than that of SCCs from the control subjects (36%, 12/33; P<.001). A greater proportion of patients with Fanconi anemia and SCC were homozygous for Arg72, a p53 polymorphism that may be associated with increased risk for HPV-associated human malignancies, than an ethnically-matched cohort of Fanconi anemia patients without SCC (75% versus 51%; P =.05). These data suggest that Fanconi anemia is associated with increased susceptibility to HPV-induced carcinogenesis. [ABSTRACT FROM AUTHOR]

Objective.--Primary mucosal melanomas are rare tumors. We compare melanomas arising in 2 histologically different mucosa, the stratified oral squamous mucosa and pseudostratified sinonasal respiratory mucosa, to investigate the clinicopathologic influence of native mucosal histology on the tumor. Methods.--Clinicopathologic features of 36 melanomas arising in the squamous mucosa of the oral cavity were compared with 59 melanomas arising in the sinonasal respiratory mucosa. Results--The median age of patients was 61 and 63 years for oral and sinonasal melanomas, respectively, with the squamous and respiratory mucosa covering the maxilla being most frequently involved (68.7% and 66%, respectively). The former had a remarkable male predilection (28 men, 8 women), while the latter affected both sexes equally (29 men, 30 women). The oral melanomas were more likely to be detected in the early in situ or microinvasive stage (4 cases vs none, P = .008) and were more frequently amelanotic (14 vs 12, P = .049) than sinonasal melanomas. The sinonasal melanomas were frequently thicker (median thickness, 9 vs 2.6 mm), polypoid (29 vs none), ulcerated (57 vs 20), and necrotic (57 vs 14) than oral melanoma ( P < .001). Pseudopapillary architecture was more frequent in sinonasal melanomas (16 tumors vs none, P < .001), and desmoplastic melanomas were more frequent in the oral mucosa (6 vs 1, P = .005). Sinonasal melanoma showed vascular and deep tissue invasion more frequently than oral melanoma; however, no significant difference in disease-specific survival was noted (median survival, 2.8 years vs 3.0 years; 5-year survival, 37% vs 35%, respectively). Conclusion.--Sinonasal melanomas demonstrated aggressive morphologic features significantly more frequently than oral melanomas; however, prognosis remained similar in both groups. [ABSTRACT FROM AUTHOR]