954 resultados para Osseous metastasis


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Reports remain insufficient on whether and how prostate-specific membrane antigen (PSMA) can influence in vivo osseous metastasis of prostate cancer (PCa). In the present study, the authors induced stable expression of PSMA in mouse PCa cell line RM-1. In vivo osseous metastasis was induced in 37 6-week-old female C57BL/6 mice weighing 22.45 ± 0.456 g. RM-1 cells were actively injected into the femoral bone cavity, leading to bilateral dissymmetry of bone density in the femoral bone. Tumor cells were also detected in bone tissue by pathological examination. The impact on bone density was demonstrated by the significant difference between animals injected with RM-PSMA cells (0.0738 ± 0.0185 g/cm²) and animals injected with RM-empty plasmid cells (0.0895 ± 0.0241 g/cm²). The lytic bone lesion of the RM-PSMA group (68.4%) was higher than that of the control group (27.8%). Immunohistochemistry showed that the expression of both vascular endothelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP-9) was distinctly higher in the RM-PSMA group than in the control group, while ELISA and Western blot assay indicated that VEGF and MMP-9 were higher in the RM-PSMA group compared to the control group (in vitro). Thus, the present study proposed and then confirmed for the first time that PSMA can promote in vivo osseous metastasis of PCa by increasing sclerotic destruction of PCa cells. Further analyses also suggested that PSMA functions positively on the invasive ability of RM-1 by increasing the expression of MMP-9 and VEGF by osseous metastases in vivo

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OBJECTIVE: The purpose of this study was to evaluate, in relation to intraoperative estimated blood loss (EBL), the effectiveness of preoperative transcatheter arterial embolization of hypervascular osseous metastatic lesions before orthopedic resection and stabilization. MATERIALS AND METHODS: Between June 1987 and November 2007, 22 patients underwent transcatheter arterial embolization of tumors of the long bone, hip, or vertebrae before resection and stabilization. Osseous metastatic lesions from renal cell carcinoma, malignant melanoma, leiomyosarcoma, and prostate cancer were embolized. All patients were treated with a coaxial catheter technique with polyvinyl alcohol (PVA) particles alone or a combination of PVA particles and coils. After embolization, each tumor was angiographically graded according to devascularization (grades 1-3) based on tumor blush after contrast injection into the main tumor-feeding arteries. RESULTS: In patients with complete devascularization (grade 1), mean EBL was calculated to be 1,119 mL, whereas in patients with partial embolization (grades 2 and 3) EBL was 1,788 mL and 2,500 mL. With respect to intraoperative EBL, no significant difference between devascularization grades was found (p > 0.05). Moderate correlation (r = 0.51, p = 0.019) was observed between intraoperative EBL and tumor size before embolization. Only low correlation (r = 0.44, p = 0.046) was found between intraoperative EBL and operating time. Major complications included transient palsy of the sciatic nerve and gluteal abscess in one patient. CONCLUSION: The results of this study support the concept that there is no statistically significant difference among amounts of intraoperative EBL with varying degrees of embolization.

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BACKGROUND: It is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis. METHODS: We performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body 18F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression. RESULTS: No patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.

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Members of the BMP and Wnt protein families play a relevant role in physiologic and pathologic bone turnover. Extracellular antagonists are crucial for the modulation of their activity. Lack of expression of the BMP antagonist noggin by osteoinductive, carcinoma-derived cell lines is a determinant of the osteoblast response induced by their bone metastases. In contrast, osteolytic, carcinoma-derived cell lines express noggin constitutively. We hypothesized that cancer cell-derived noggin may contribute to the pathogenesis of osteolytic bone metastasis of solid cancers by repressing bone formation. Intra-osseous xenografts of PC-3 prostate cancer cells induced osteolytic lesions characterized not only by enhanced osteoclast-mediated bone resorption, but also by decreased osteoblast-mediated bone formation. Therefore, in this model, uncoupling of the bone remodeling process contributes to osteolysis. Bone formation was preserved in the osteolytic lesions induced by noggin-silenced PC-3 cells, suggesting that cancer cell-derived noggin interferes with physiologic bone coupling. Furthermore, intra-osseous tumor growth of noggin-silenced PC-3 cells was limited, most probably as a result of the persisting osteoblast activity. This investigation provides new evidence for a model of osteolytic bone metastasis where constitutive secretion of noggin by cancer cells mediates inhibition of bone formation, thereby preventing repair of osteolytic lesions generated by an excess of osteoclast-mediated bone resorption. Therefore, noggin suppression may be a novel strategy for the treatment of osteolytic bone metastases.

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Squamous cell carcinoma is the most common neoplasm of the larynx, and its evolution depends on tumor staging. Vascular endothelial growth factor is a marker of angiogenesis, and its expression may be related to increased tumor aggressiveness, as evidenced by the presence of cervical lymphatic metastases. To evaluate the expression of the vascular endothelial growth factor marker in non-glottic advanced squamous cell carcinoma of the larynx (T3/T4) and correlate it with the presence of cervical lymph node metastases. Retrospective clinical study and immunohistochemical analysis of vascular endothelial growth factor through the German scale of immunoreactivity in products of non-glottic squamous cell carcinomas. This study analyzed 15 cases of advanced non-glottic laryngeal tumors (T3/T4), four of which exhibited cervical lymphatic metastases. There was no correlation between vascular endothelial growth factor expression and the presence of cervical metastases. Although vascular endothelial growth factor was expressed in a few cases, there was no correlation with the spread of cervical lymph metastases.

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PURPOSE: To study were to reproduce an alveolar bone defect model in Wistar rats to be used for testing the efficacy of stem cell therapies. Additionally, we also aimed to determine the osteogenesis process of this osseous defect in the 1 month period post-surgery. METHODS: The animals were randomly divided into two groups of 7 animals each. A gingivobuccal incision was made, and a bone defect of 28 mm² of area was performed in the alveolar region. Animals were killed at 2 weeks after surgery (n=7) and 4 weeks after surgery (n=7). RESULTS: The average area of the alveolar defect at time point of 2 weeks was 22.27 ± 1.31 mm² and the average area of alveolar defect at time point of 4 weeks was 9.03 ± 1.17 mm². The average amount of bone formation at time point of 2 weeks was 5.73 ± 1.31 mm² and the average amount of bone formation at time point of 4 weeks was 19 ± 1.17 mm². Statistically significant differences between the amount of bone formation at 2 weeks and 4 weeks after surgery were seen (p=0.003). CONCLUSION: The highest rate of ossification occurred mostly from 2 to 4 weeks after surgery. This observation suggests that 4 weeks after the bone defect creation should be a satisfactory timing to assess the potential of bone inductive stem cells to accelerate bone regeneration in Wistar rats.

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Abstract Objectives to evaluate risk factors for recurrence of carcinoma of the uterine cervix among women who had undergone radical hysterectomy without pelvic lymph node metastasis, while taking into consideration not only the classical histopathological factors but also sociodemographic, clinical and treatment-related factors. Study desin This was an exploratory analysis on 233 women with carcinoma of the uterine cervix (stages IB and IIA) who were treated by means of radical hysterectomy and pelvic lymphadenectomy, with free surgical margins and without lymph node metastases on conventional histopathological examination. Women with histologically normal lymph nodes but with micrometastases in the immunohistochemical analysis (AE1/AE3) were excluded. Disease-free survival for sociodemographic, clinical and histopathological variables was calculated using the Kaplan-Meier method. The Cox proportional hazards model was used to identify the independent risk factors for recurrence. Twenty-seven recurrences were recorded (11.6%), of which 18 were pelvic, four were distant, four were pelvic + distant and one was of unknown location. The five-year disease-free survival rate among the study population was 88.4%. The independent risk factors for recurrence in the multivariate analysis were: postmenopausal status (HR 14.1; 95% CI: 3.7-53.6; P < 0.001), absence of or slight inflammatory reaction (HR 7.9; 95% CI: 1.7-36.5; P = 0.008) and invasion of the deepest third of the cervix (HR 6.1; 95% CI: 1.3-29.1; P = 0.021). Postoperative radiotherapy was identified as a protective factor against recurrence (HR 0.02; 95% CI: 0.001-0.25; P = 0.003). (To continue) Postmenopausal status is a possible independent risk factor for recurrence even when adjusted for classical prognostic factors (such as tumour size, depth of tumour invasion, capillary embolisation) and treatment-related factors (period of treatment and postoperative radiotherapy status)

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Perforin (pfp) and interferon-gamma (IFN-gamma) together in C57BL/6 (B6) and BALB/c mouse strains provided optimal protection in 3 separate tumor models controlled by innate immunity. Using experimental (B6, RM-1 prostate carcinoma) and spontaneous (BALB/c, DA3 mammary carcinoma) models of metastatic cancer, mice deficient in both pfp and IFN-gamma were significantly less proficient than pfp- or IFN-gamma -deficient mice in preventing metastasis of tumor cells to the lung. Pfp and IFN-gamma -deficient mice were as susceptible as mice depleted of natural killer (NK) cells in both tumor metastasis models, and IFN-gamma appeared to play an early role in protection from metastasis, Previous experiments in a model of fibrosarcoma induced by the chemical carcinogen methylcholanthrene indicated an important role for NK1.1(+) T cells, Herein, both pfp and IFN-gamma played critical and independent roles in providing the host with protection equivalent to that mediated by NK1.1+ T cells, Further analysis demonstrated that IFN-gamma, but not pfp, controlled the growth rate of sarcomas arising in these mice. Thus, this is the first study to demonstrate that host IFN-gamma, and direct cytotoxicity mediated by cytotoxic lymphocytes expressing pfp independently contribute antitumor effector functions that together control the initiation, growth, and spread of tumors in mice, (C) 2001 by The American Society of Hematology.

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We have characterized the kinetic properties of ectonucleoside triphosphate diphosphohydrolase 1 (E-NTPDase1) from rat osseous plate membranes. A novel finding of the present study is that the solubilized enzyme shows high- and low-affinity sites for the substrate in contrast with a single substrate site for the membrane-bound enzyme. In addition, contrary to the Michaelian chraracteristics of the membrane-bound enzyme, the site-site interactions after solubilization with 0.5% digitonin plus 0.1% lysolecithin resulted in a less active ectonucleoside triphosphate diphosphohydrolase, showing activity of about 398.3 nmol Pi min(-1) mg(-1). The solubilized enzyme has M(r) of 66-72 kDa, and its catalytic efficiency was significantly increased by magnesium and calcium ions; but the ATP/ADP activity ratio was always < 2.0. Partial purification and kinetic characterization of the rat osseous plate E-NTPDase1 in a solubilized form may lead to a better understanding of a possible function of the enzyme as a modulator of nucleotidase activity or purinergic signaling in matrix vesicle membranes. The simple procedure to obtain the enzyme in a solubilized form may also be attractive for comparative studies of particular features of the active sites from this and other ATPases.

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A glycosylphosphatidylinositol (GPI)-anchored enzyme (rat osseous plate alkaline phosphatase-OAP) was studied as monolayer (pure and mixed with lipids) at the air-water interface. Surface pressure and surface potential-area isotherms showed that the enzyme forms a stable monolayer and exhibits a liquid-expanded state even at surface pressure as high as 30 mN m(-1). Isotherms for mixed dimyristoylphosphatidic acid (DMPA)-OAP monolayer showed the absence of a liquid-expanded/liquid-condensed phase transition as observed for pure DMPA monolayer. In both cases, pure or mixed monolayer, the enzyme preserves its native conformation under compression at the air-water interface as observed from in situ p-polarized light Fourier transform-infrared reflection-absorption spectroscopic (FT-IRRAS) measurements. Changes in orientation and conformation of the enzyme due to the presence or absence of DMPA, as well as due to the surface compression, are discussed. (C) 2008 Published by Elsevier Inc.

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Purpose: To identify papillary thyroid carcinoma (PTC)-associated transcripts, we compared the gene expression profiles of three Serial Analysis of Gene Expression libraries generated from thyroid tumors and a normal thyroid tissue. Experimental Design: Selected transcripts were validated in a panel of 57 thyroid tumors using quantitative PCR (qPCR). An independent set of 71 paraffin-embedded sections was used for validation using immunohistochemical analysis. To determine if PTC-associated gene expression could predict lymph node involvement, a separate cohort of 130 primary PTC (54 metastatic and 76 nonmetastatic) was investigated. The BRAF(V600E) mutational status was compared with qPCR data to identify genes that might be regulated by abnormal BRAF/MEK/extracellular signal-regulated kinase signaling. Results: We identified and validated new PTC-associated transcripts. Three genes (CST6, CXCL14, and DHRS3) are strongly associated with PTC. Immunohistochemical analysis of CXCL14 confirmed the qPCR data and showed protein expression in PTC epithelial cells. We also observed that CST6, CXCL14, DHRS3, and SPP1 were associated with PTC lymph node metastasis, with CST6, CXCL14, and SPP1 being positively correlated with metastasis and DHRS3 being negatively correlated. Finally, we found a strong correlation between CST6 and CXCL14 expression and BRAF(V600E) mutational status, suggesting that these genes may be induced subsequently to BRAF activation and therefore may be downstream in the BRAF/MEK/extracellular signal-regulated kinase signaling pathway. Conclusion: CST6, CXCL14, DHRS3, and SPP1 may play a role in PTC pathogenesis and progression and are possible molecular targets for FTC therapy.

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Background: Depth of tumor invasion (T-category) and the number of metastatic lymph nodes (N-category) are the most important prognostic factors in patients with gastric cancer. Recently, the ratio between metastatic and dissected lymph nodes (N-ratio) has been established as one. The aim of this study is to evaluate the impact of N-ratio and its interaction with N-category as a prognostic factor in gastric cancer. Methods: This was a retrospective study in which we reviewed clinical and pathological data of 165 patients who had undergone curative surgery at our institution through a 9-year period. The exclusion criteria included metastases, gastric stump tumors and gastrectomy with less than 15 lymph nodes dissected. Results: The median age of the patients was 63 years and most of them were male. Total gastrectomy was the most common procedure and 92.1% of the patients had a D2-lymphadenectomy. Their 5-year overall survival was 57.7%. T-category, N-category, extended gastrectomy, and N-ratio were prognostic factors in overall and disease-free survival in accordance with univariate analysis. In accordance with TNM staging, N1 patients who have had NR1 had 5-year survival in 75.5% whereas in the NR2 group only 33% of the cases had 5-year survival. In the multivariate analysis, the interaction between N-category and N-ratio was an independent prognostic factor. Conclusion: Our findings confirmed the role of N-ratio as prognostic factor of survival in patients with gastric cancer surgically treated with at least 15 lymph nodes dissected. The relationship between N-category and N-ratio is a better predictor than lymph node metastasis staging. (C) 2010 Elsevier Ltd. All rights reserved.

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To evaluate the usefulness of intraoral ultrasonography (IOUS) as a tool for predicting neck metastasis. Squamous cell carcinoma (SCC) of the tongue is aggressive and has a great propensity to metastasize to cervical lymph nodes. SCC of the oral cavity has a worse prognosis when associated with metastatic cervical nodes. Therefore, the metastatic potential of tongue carcinoma should be graded preoperatively to help determine the requirement for neck dissection. Nineteen patients (11 men, 8 women) between 36 and 79 years of age (mean age 60) with T1 to T4a TNM-stage tongue carcinomas were evaluated preoperatively with IOUS. Clinical and pathological TNM classifications were performed. The average tumor thicknesses measured using histological sections were significantly (p < 0.01) lower than those with IOUS (1.3 vs. 1.6 cm, respectively). A significant correlation was observed between the tumor thickness measured using ultrasonography and that measured using histological sections (pathology). Based on this greater accuracy, the cutoff point of tumor thickness based on IOUS evaluation for predicting neck metastasis was determined to be 1.8 cm. Some factors may influence neck metastasis. A knowledge of these would help to avoid unnecessary surgical intervention for N0 patients. The results of this study indicates that there is a significant correlation between neck metastasis and tumor thickness. Intraoral ultrasonography is useful tool for identifying tongue tumors and measuring their thickness, with the thickness measured by IOUS showing a very good correlation with histological measurements. Moreover, IOUS provides prognostic information prior to surgical treatment since tumor thickness can predict the chance of recognizing metastatic cervical nodes.

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Hepatectomy may prolong the survival of colorectal cancer patients with liver metastases. Two-stage liver surgery is a valid option for the treatment of bilobar colorectal liver metastasis. This video demonstrates technical aspects of a two-stage pure laparoscopic hepatectomy for bilateral liver metastasis. To the authors` knowledge, this is the first description of a two-stage laparoscopic liver resection in the English literature. A 54-year-old man with right colon cancer and synchronous bilobar colorectal liver metastasis underwent laparoscopic right colon resection followed by oxaliplatin-based chemotherapy. The patient then was referred for surgical treatment of liver metastasis. Liver volumetry showed a small left liver remnant. Surgical planning was for a totally laparoscopic two-stage liver resection. The first stage involved laparoscopic resection of segment 3 and ligature of the right portal vein. The postoperative pathology showed high-grade liver steatosis. After 4 weeks, the left liver had regenerated, and volumetry of left liver was 43%. The second stage involved laparoscopic right hepatectomy using the intrahepatic Glissonian approach. Intrahepatic access to the main right Glissonian pedicle was achieved with two small incisions, and an endoscopic vascular stapling device was inserted between these incisions and fired. The line of liver transection was marked following the ischemic area. Liver transection was accomplished with the Harmonic scalpel and an endoscopic stapling device. The specimen was extracted through a suprapubic incision. The falciform ligament was fixed to maintain the left liver in its original anatomic position, avoiding hepatic vein kinking and outflow syndrome. The operative time was 90 min for stage 1 and 240 min for stage 2 of the procedure. The recoveries after the first and second operations were uneventful, and the patient was discharged on postoperative days 2 and 7, respectively. Two-stage liver resections can be performed safely using laparoscopy. The intrahepatic Glissonian approach is a useful tool for pedicle control of the right liver, especially after previous dissection of the hilar plate.

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Members of the nuclear factor of activated T cell (NFAT) family of transcription factors were originally described in T lymphocytes but later shown to be expressed in several immune and non-immune cell types. NFAT proteins can modulate cellular transformation intrinsically, and NFAT-deficient (NFAT1-/-) mice are indeed more susceptible to transformation than wild-type counterparts. However, the contribution of an NFAT1-/- microenvironment to tumor progression has not been studied. We have addressed this question by inoculating NFAT1-/- mice with B16F10 melanoma cells intravenously, an established model of tumor homing and growth. Surprisingly, NFAT1-/- animals sustained less tumor growth in the lungs after melanoma inoculation than wild-type counterparts. Even though melanoma cells equally colonize NFAT1-/- and wild-type lungs, tumors do not progress in the absence of NFAT1 expression. A massive mononuclear perivascular infiltrate and reduced expression of TGF-beta in the absence of NFAT1 suggested a role for tumor-infiltrating immune cells and the cytokine milieu. However, these processes are independent of an IL-4-induced regulatory tumor microenvironment, since lack of this cytokine does not alter the phenotype in NFAT1-/- animals. Bone marrow chimera experiments meant to differentiate the contributions of stromal and infiltrating cells to tumor progression demonstrated that NFAT1-induced susceptibility to pulmonary tumor growth depends on NFAT1-expressing parenchyma rather than on bone marrow-derived cells. These results suggest an important role for NFAT1 in radio-resistant tumor-associated parenchyma, which is independent of the anti-tumor immune response and Th1 versus Th2 cytokine milieu established by the cancer cells, but able to promote site-specific tumor growth.