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BackgroundDiffuse midline glioma, formerly DIPG (diffuse intrinsic pontine glioma), is the deadliest pediatric brainstem tumor with median survival of less than one year. Here, we investigated (i) whether direct delivery of adenovirus-expressing cluster of differentiation (CD)40 ligand (Ad-CD40L) to brainstem tumors would induce immune-mediated tumor clearance and (ii) if so, whether therapy would be associated with a manageable toxicity due to immune-mediated inflammation in the brainstem.MethodsSyngeneic gliomas in the brainstems of immunocompetent mice were treated with Ad-CD40L and survival, toxicity, and immune profiles determined. A clinically translatable vector, whose replication would be tightly restricted to tumor cells, rAd-Δ24-CD40L, was tested in human patient–derived diffuse midline gliomas and immunocompetent models.ResultsExpression of Ad-CD40L restricted to brainstem gliomas by pre-infection induced complete rejection, associated with immune cell infiltration, of which CD4+ T cells were critical for therapy. Direct intratumoral injection of Ad-CD40L into established brainstem tumors improved survival and induced some complete cures but with some acute toxicity. RNA-sequencing analysis showed that Ad-CD40L therapy induced neuroinflammatory immune responses associated with interleukin (IL)-6, IL-1β, and tumor necrosis factor α. Therefore, to generate a vector whose replication, and transgene expression, would be tightly restricted to tumor cells, we constructed rAd-Δ24-CD40L, the backbone of which has already entered clinical trials for diffuse midline gliomas. Direct intratumoral injection of rAd-Δ24-CD40L, with systemic blockade of IL-6 and IL-1β, generated significant numbers of cures with readily manageable toxicity.ConclusionsVirus-mediated delivery of CD40L has the potential to be effective in treating diffuse midline gliomas without obligatory neuroinflammation-associated toxicity.  相似文献   
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Diffuse gastric cancer (DGC) is a lethal malignancy lacking effective systemic therapy. Among the most provocative recent results in DGC has been that the alter of the cellular cytoskeleton and intercellular adhesion. CD2-associated protein (CD2AP) is one of the critical proteins regulating cytoskeleton assembly and intercellular adhesion. However, no study has investigated the expression and biological significance of CD2AP in gastric cancer (GC) to date. Therefore, the aim of our study was to explore if the expression of CD2AP is associated with any clinical features of GC and to elucidate the underlying mechanism. Immunohistochemistry of 620 patient tissue samples indicated that the expression of CD2AP is downregulated in DGC. Moreover, a low CD2AP level was indicative of poor patient prognosis. In vitro, forced expression of CD2AP caused a significant decrease in the migration and invasion of GC cells, whereas depletion of CD2AP had the opposite effect. Immunofluorescence analysis indicated that CD2AP promoted cellular adhesion and influenced cell cytoskeleton assembly via interaction with the F-actin capping protein CAPZA1. Overall, the upregulation of CD2AP could attenuate GC metastasis, suggesting CD2AP as a novel biomarker for the prognosis and treatment of patients with GC.  相似文献   
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《Molecular therapy》2020,28(6):1432-1441
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The interaction of CD47 and signal-regulatory protein alpha (SIRPα) induces “don't eat me signal”, leading suppression of phagocytosis. This signal can affect the clinical course of malignant disease. Although CD47 and SIRPα expression are associated with clinicopathological features in several neoplasms, the investigation for adult T-cell leukemia/lymphoma (ATLL) has not been well-documented. This study aimed to declare the association between CD47 and SIRPα expression and clinicopathological features in ATLL. We performed immunostaining on 73 biopsy samples and found that CD47 is primarily expressed in tumor cells, while SIRPα is expressed in non-neoplastic stromal cells. CD47 positive cases showed significantly higher FoxP3 (P = .0232) and lower CCR4 (P = .0214). SIRPα positive cases presented significantly better overall survival than SIRPα negative cases (P = .0132). SIRPα positive cases showed significantly HLA class I (P = .0062), HLA class II (P = .0133), microenvironment PD-L1 (miPD-L1) (P = .0032), and FoxP3 (P = .0229) positivity. In univariate analysis, SIRPα expression was significantly related to prognosis (Hazard ratio [HR] 0.470; 95% confidence interval [CI] 0.253-0.870; P = .0167], although multivariate analysis did not show SIPRα as an independent prognostic factor. The expression of SIRPα on stromal cells reflects activated immune surveillance mechanism in tumor microenvironment and induce good prognosis in ATLL. More detailed studies for gene expression or genomic abnormalities will disclose clinical and biological significance of the CD47 and SIRPα in ATLL.  相似文献   
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目的 :观察MDA-7/IL-24基因对肝癌的选择性杀伤作用,为肝癌的基因治疗提供理论基础。 方法 :将携带人MDA-7/IL-24基因的腺病毒Ad.mda-7感染人正常肝细胞L02和肝癌细胞HepG2;用RT-PCR法观察MDA-7/IL-24基因的表达;ELISA方法检测细胞培养上清液中MDA-7/IL-24蛋白的浓度;4甲基偶氮唑蓝染色法(MTT)及Hoechst染色观察MDA-7/IL-24对肝癌细胞的生长抑制和杀伤作用;Annexin-V和PI双染后流式细胞仪检测2种细胞的凋亡;用流式细胞仪检测细胞周期。 结果 :复制缺陷型腺病毒能介导外源基因MDA-7/IL-24在肝癌细胞株HepG2和正常细胞L02中的高效表达;细胞培养上清液中有MDA-7/IL-24蛋白的表达; MDA-7/IL-24能明显抑制肝癌细胞生长并可促进肝癌细胞的凋亡;MDA-7/IL-24阻滞肝癌细胞于G2/M期,能选择性杀伤肝癌细胞而对正常的肝细胞无阻滞作用和毒性作用。结论 :复制缺陷型重组腺病毒载体Ad.mda-7能介导MDA-7/IL-24基因在人肝癌细胞中高效表达,促使细胞增殖阻滞及诱导肿瘤细胞凋亡,选择性地杀伤肝癌细胞HepG2,而对正常肝细胞L02无任何毒性作用。  相似文献   
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目的研究CD10表达在甲状腺滤泡性癌和滤泡型乳头状癌诊断中的作用。方法收集70例甲状腺良、恶性病变组织,其中包括15例滤泡性腺瘤、15例腺瘤性甲状腺肿、30例乳头状癌(包括9例滤泡型乳头状癌)和10例滤泡性癌,采用免疫组织化学方法检测CD10在上述组织中的表达。结果9例滤泡型乳头状癌中,7例表达CD10(77.8%),10例滤泡性癌中8例表达CD10(80.0%);CD10在非滤泡型乳头状癌、滤泡性腺瘤、腺瘤性甲状腺肿和正常甲状腺组织中均不表达。结论对CD10表达的检测有助于对甲状腺滤泡性癌和滤泡型乳头状癌的诊断。  相似文献   
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