446 resultados para laterally spreading tumor
Retroviral infection of the neonatal Peyer's Patch lymphocytes : the mouse mammary tumor virus model
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PURPOSE: To report the clinico-pathological features of solitary fibrous tumor occurring in the ocular adnexa (OA) in a single center. To assess the presence of NAB2-STAT6 genes fusion in OA solitary fibrous tumor detected by nuclear overexpression of STAT6. METHODS: Retrospective study including orbital and OA solitary fibrous tumors treated between 2006 and 2014 in our center. The clinical, radiological, and histopathological findings were evaluated. STAT6 expression was assessed by immunohistochemistry. RESULTS: Five patients were identified and presented with a chronic OA mass. The tumors were radiologically well delimited, highly vascularized and without bone erosion. All the patients underwent complete surgical excision. Pathological examination confirmed solitary fibrous tumor in all cases. All tumors demonstrated a nuclear expression of STAT6. There were no recurrences, with a mean follow-up of 5 years after surgery. Our review demonstrated that proptosis was the most common presentation occurring in 60 % of the cases. In the ocular adnexa, adverse histological criteria were found in 19.7 % of the tumors, and recurrences were observed in 48 % of these cases. Thirty-six percent of patients presented at least one local recurrence, and metastastic spread was found in 2.4 % of the cases. Tumor-related death was described in two cases. CONCLUSION: Ocular adnexal SFT are rare and usually present as a chronic orbital mass with proptosis. In the OA, solitary fibrous tumor demonstrates STAT6 nuclear expression, as documented in other locations. Recurrences are unusual and metastasis exceptional. Initial surgical resection should be complete in order to avoid recurrence.
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Objectives: This study aims to investigate the efficacy of tumor necrosis factor-alpha blockers such as infliximab, etanercept, and adalimumab in the treatment of ankylosing spondylitis. Patients and methods: The outcome of tumor necrosis factor-alpha blocker treatment was analyzed retrospectively in 59 patients with ankylosing spondylitis who were being treated in our clinic during last nine years. The patients' Assessment of SpondyloArthritis International Society (ASAS) 20 and ASAS 40 response rates, adverse drugs effects, and treatment compliance were evaluated. Results: ASAS 20 response was achieved by 89.8% of the patients in the third month, and by 93.2% in the sixth month. ASAS 40 response was achieved by 61% of the patients in the third and sixth month. No statistically significant difference was detected between the three tumor necrosis factor-alpha blockers with regards to the ASAS 40 response rates. Mild infections, observed in 31 of the patients, were the most common side effects. Serious side effect was observed in only one patient. The number of patients who withdrew from the treatment for various reasons was six.
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Acute pulmonary hypertension leading to right ventricular failure and circulatory collapse is usually caused by thromboembolic obstruction of the pulmonary circulation. However, in rare instances, other causes can be associated with a similar clinical presentation. We present and discuss the clinical histories of two patients with acute right ventricular failure due to an atypical cause of pulmonary hypertension, disseminated pulmonary tumor embolism.
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BACKGROUND: Immune checkpoint inhibitors targeting programmed cell death 1 (PD1) or its ligand (PD-L1) showed activity in several cancer types. METHODS: We performed immunohistochemistry for CD3, CD8, CD20, HLA-DR, phosphatase and tensin homolog (PTEN), PD-1, and PD-L1 and pyrosequencing for assessment of the O6-methylguanine-methyltransferase (MGMT) promoter methylation status in 135 glioblastoma specimens (117 initial resection, 18 first local recurrence). PD-L1 gene expression was analyzed in 446 cases from The Cancer Genome Atlas. RESULTS: Diffuse/fibrillary PD-L1 expression of variable extent, with or without interspersed epithelioid tumor cells with membranous PD-L1 expression, was observed in 103 of 117 (88.0%) newly diagnosed and 13 of 18 (72.2%) recurrent glioblastoma specimens. Sparse-to-moderate density of tumor-infiltrating lymphocytes (TILs) was found in 85 of 117 (72.6%) specimens (CD3+ 78/117, 66.7%; CD8+ 52/117, 44.4%; CD20+ 27/117, 23.1%; PD1+ 34/117, 29.1%). PD1+ TIL density correlated positively with CD3+ (P < .001), CD8+ (P < .001), CD20+ TIL density (P < .001), and PTEN expression (P = .035). Enrichment of specimens with low PD-L1 gene expression levels was observed in the proneural and G-CIMP glioblastoma subtypes and in specimens with high PD-L1 gene expression in the mesenchymal subtype (P = 5.966e-10). No significant differences in PD-L1 expression or TIL density between initial and recurrent glioblastoma specimens or correlation of PD-L1 expression or TIL density with patient age or outcome were evident. CONCLUSION: TILs and PD-L1 expression are detectable in the majority of glioblastoma samples but are not related to outcome. Because the target is present, a clinical study with specific immune checkpoint inhibitors seems to be warranted in glioblastoma.
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Background. Perivascular epithelioid cell tumors (PEComas) are a rare family of mesenchymal tumors arising in a wide array of anatomic locations and characterized by coexpression of melanocytic and muscle markers. The uterus accounts for around one-fourth of the overall PEComa cases reported in the literature. Methods. We report a case of PEComa of the uterus with multiple malignancy features. Results. A uterine mass suspect for leiomyosarcoma was found in a 53-year-old woman with post-menopausal bleeding. Total hysterectomy and bilateral adnexectomy was performed. The tumor measured 7 cm in diameter, was unique, well-circumscribed, nodular, and whiteyellow without haemorrhage or necrosis. Microscopically, two populations of cells could be seen: small fusiform cells growing in fascicles resembling a smooth muscle tumor, and large epithelioid cells with abundant pale vacuolated cytoplasm growing in a diffuse pattern. Cytologic atypias were marked and mitoses numerous and often atypical in the second component. The tumor infiltrated into the myometrium with lymphovascular invasion. Immunostains showed positivity for MelanA, HMB45, smooth muscle actin, CD10, TFE3 and cathepsin K. Conclusions. This PEComa case presents several of the recently precised criteria for malignancy (Schoolmeester JK et al. Perivascular epithelioid cell neoplasm (PEComa) of the gynecologic tract: Clinicopathologic and immunohistochemical characterization of 16 cases. Am J Surg Pathol 2014; 38:176-188).
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Tumor antigen-specific CD4(+) T cells generally orchestrate and regulate immune cells to provide immune surveillance against malignancy. However, activation of antigen-specific CD4(+) T cells is restricted at local tumor sites where antigen-presenting cells (APCs) are frequently dysfunctional, which can cause rapid exhaustion of anti-tumor immune responses. Herein, we characterize anti-tumor effects of a unique human CD4(+) helper T-cell subset that directly recognizes the cytoplasmic tumor antigen, NY-ESO-1, presented by MHC class II on cancer cells. Upon direct recognition of cancer cells, tumor-recognizing CD4(+) T cells (TR-CD4) potently induced IFN-γ-dependent growth arrest in cancer cells. In addition, direct recognition of cancer cells triggers TR-CD4 to provide help to NY-ESO-1-specific CD8(+) T cells by enhancing cytotoxic activity, and improving viability and proliferation in the absence of APCs. Notably, the TR-CD4 either alone or in collaboration with CD8(+) T cells significantly inhibited tumor growth in vivo in a xenograft model. Finally, retroviral gene-engineering with T cell receptor (TCR) derived from TR-CD4 produced large numbers of functional TR-CD4. These observations provide mechanistic insights into the role of TR-CD4 in tumor immunity, and suggest that approaches to utilize TR-CD4 will augment anti-tumor immune responses for durable therapeutic efficacy in cancer patients.
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Spontaneous CD8 T-cell responses occur in growing tumors but are usually poorly effective. Understanding the molecular and cellular mechanisms that drive these responses is of major interest as they could be exploited to generate a more efficacious antitumor immunity. As such, stimulator of IFN genes (STING), an adaptor molecule involved in cytosolic DNA sensing, is required for the induction of antitumor CD8 T responses in mouse models of cancer. Here, we find that enforced activation of STING by intratumoral injection of cyclic dinucleotide GMP-AMP (cGAMP), potently enhanced antitumor CD8 T responses leading to growth control of injected and contralateral tumors in mouse models of melanoma and colon cancer. The ability of cGAMP to trigger antitumor immunity was further enhanced by the blockade of both PD1 and CTLA4. The STING-dependent antitumor immunity, either induced spontaneously in growing tumors or induced by intratumoral cGAMP injection was dependent on type I IFNs produced in the tumor microenvironment. In response to cGAMP injection, both in the mouse melanoma model and an ex vivo model of cultured human melanoma explants, the principal source of type I IFN was not dendritic cells, but instead endothelial cells. Similarly, endothelial cells but not dendritic cells were found to be the principal source of spontaneously induced type I IFNs in growing tumors. These data identify an unexpected role of the tumor vasculature in the initiation of CD8 T-cell antitumor immunity and demonstrate that tumor endothelial cells can be targeted for immunotherapy of melanoma.
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IMPORTANCE: Glioblastoma is the most devastating primary malignancy of the central nervous system in adults. Most patients die within 1 to 2 years of diagnosis. Tumor-treating fields (TTFields) are a locoregionally delivered antimitotic treatment that interferes with cell division and organelle assembly. OBJECTIVE: To evaluate the efficacy and safety of TTFields used in combination with temozolomide maintenance treatment after chemoradiation therapy for patients with glioblastoma. DESIGN, SETTING, AND PARTICIPANTS: After completion of chemoradiotherapy, patients with glioblastoma were randomized (2:1) to receive maintenance treatment with either TTFields plus temozolomide (n = 466) or temozolomide alone (n = 229) (median time from diagnosis to randomization, 3.8 months in both groups). The study enrolled 695 of the planned 700 patients between July 2009 and November 2014 at 83 centers in the United States, Canada, Europe, Israel, and South Korea. The trial was terminated based on the results of this planned interim analysis. INTERVENTIONS: Treatment with TTFields was delivered continuously (>18 hours/day) via 4 transducer arrays placed on the shaved scalp and connected to a portable medical device. Temozolomide (150-200 mg/m2/d) was given for 5 days of each 28-day cycle. MAIN OUTCOMES AND MEASURES: The primary end point was progression-free survival in the intent-to-treat population (significance threshold of .01) with overall survival in the per-protocol population (n = 280) as a powered secondary end point (significance threshold of .006). This prespecified interim analysis was to be conducted on the first 315 patients after at least 18 months of follow-up. RESULTS: The interim analysis included 210 patients randomized to TTFields plus temozolomide and 105 randomized to temozolomide alone, and was conducted at a median follow-up of 38 months (range, 18-60 months). Median progression-free survival in the intent-to-treat population was 7.1 months (95% CI, 5.9-8.2 months) in the TTFields plus temozolomide group and 4.0 months (95% CI, 3.3-5.2 months) in the temozolomide alone group (hazard ratio [HR], 0.62 [98.7% CI, 0.43-0.89]; P = .001). Median overall survival in the per-protocol population was 20.5 months (95% CI, 16.7-25.0 months) in the TTFields plus temozolomide group (n = 196) and 15.6 months (95% CI, 13.3-19.1 months) in the temozolomide alone group (n = 84) (HR, 0.64 [99.4% CI, 0.42-0.98]; P = .004). CONCLUSIONS AND RELEVANCE: In this interim analysis of 315 patients with glioblastoma who had completed standard chemoradiation therapy, adding TTFields to maintenance temozolomide chemotherapy significantly prolonged progression-free and overall survival. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00916409.
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Exposing the human bronchial epithelial cell line BEAS-2B to the nitric oxide (NO) donor sodium 1-(N,N-diethylamino)diazen-1-ium-1, 2-diolate (DEA/NO) at an initial concentration of 0.6 mM while generating superoxide ion at the rate of 1 microM/min with the hypoxanthine/xanthine oxidase (HX/XO) system induced C:G-->T:A transition mutations in codon 248 of the p53 gene. This pattern of mutagenicity was not seen by 'fish-restriction fragment length polymorphism/polymerase chain reaction' (fish-RFLP/PCR) on exposure to DEA/NO alone, however, exposure to HX/XO led to various mutations, suggesting that co-generation of NO and superoxide was responsible for inducing the observed point mutation. DEA/NO potentiated the ability of HX/XO to induce lipid peroxidation as well as DNA single- and double-strand breaks under these conditions, while 0.6 mM DEA/NO in the absence of HX/XO had no significant effect on these parameters. The results show that a point mutation seen at high frequency in certain common human tumors can be induced by simultaneous exposure to reactive oxygen species and a NO source.
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An increased expression of nitric oxide synthase (NOS) has been observed in human colon carcinoma cell lines as well as in human gynecological, breast, and central nervous system tumors. This observation suggests a pathobiological role of tumor-associated NO production. Hence, we investigated NOS expression in human colon cancer in respect to tumor staging, NOS-expressing cell type(s), nitrotyrosine formation, inflammation, and vascular endothelial growth factor expression. Ca2+-dependent NOS activity was found in normal colon and in tumors but was significantly decreased in adenomas (P < 0.001) and carcinomas (Dukes' stages A-D: P < 0.002). Ca2+-independent NOS activity, indicating inducible NOS (NOS2), is markedly expressed in approximately 60% of human colon adenomas (P < 0.001 versus normal tissues) and in 20-25% of colon carcinomas (P < 0.01 versus normal tissues). Only low levels were found in the surrounding normal tissue. NOS2 activity decreased with increasing tumor stage (Dukes' A-D) and was lowest in colon metastases to liver and lung. NOS2 was detected in tissue mononuclear cells (TMCs), endothelium, and tumor epithelium. There was a statistically significant correlation between NOS2 enzymatic activity and the level of NOS2 protein detected by immunohistochemistry (P < 0.01). Western blot analysis of tumor extracts with Ca2+-independent NOS activity showed up to three distinct NOS2 protein bands at Mr 125,000-Mr 138,000. The same protein bands were heavily tyrosine-phosphorylated in some tumor tissues. TMCs, but not the tumor epithelium, were immunopositive using a polyclonal anti-nitrotyrosine antibody. However, only a subset of the NOS2-expressing TMCs stained positively for 3-nitrotyrosine, which is a marker for peroxynitrite formation. Furthermore, vascular endothelial growth factor expression was detected in adenomas expressing NOS2. These data are consistent with the hypothesis that excessive NO production by NOS2 may contribute to the pathogenesis of colon cancer progression at the transition of colon adenoma to carcinoma in situ.
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Nitric oxide (NO) is a cellular messenger which is mutagenic in bacteria and human TK6 cells and induces deamination of 5-methylcytosine (5meC) residues in vitro. The aims of this study were: (i) to investigate whether NO induces 5meC deamination in codon 248 of the p53 gene in cultured human bronchial epithelial cells (BEAS-2B); and (ii) to compare NO mutagenicity to that of ethylnitrosourea (ENU), a strong mutagen. Two approaches were used: (i) a novel genotypic assay, using RFLP/PCR technology on purified exon VII sequence of the p53 gene; and (ii) a phenotypic (HPRT) mutation assay using 6-thioguanine selection. BEAS-2B cells were either exposed to 4 mM DEA/NO (Et2N[N2O2]Na, an agent that spontaneously releases NO into the medium) or transfected with the inducible nitric oxide synthase (iNOS) gene. The genotypic mutation assay, which has a sensitivity of 1 x 10(-6), showed that 4 mM ENU induces detectable numbers of G --> A transitions in codon 248 of p53 while 5-methylcytosine deamination was not detected in either iNOS-transfected cells or cells exposed to 4 mM DEA/NO. Moreover, ENU was dose-responsively mutagenic in the phenotypic HPRT assay, reaching mutation frequencies of 24 and 96 times that of untreated control cells at ENU concentrations of 4 and 8 mM respectively; by contrast, 4 mM DEA/NO induced no detectable mutations in this assay, nor were any observed in cells transfected with murine iNOS. We conclude that if NO is at all promutagenic in these cells, it is significantly less so than the ethylating mutagen, ENU.