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41.
Systemic inflammation might modulate the microenvironment in the lungs and promotes metastasis. E-selectin, an inflammation inducible endothelial cell adhesion molecule, has been reported to play an important role in homing metastatic cancer cells. To study the effects of E-selectin expression induced by systemic inflammation on breast cancer metastasis, we first treated BALB/c mice with lipopolysaccharide (LPS) to induce systemic inflammation. Pulmonary tissues were analyzed by wet/dry ratio, hematoxylin and eosin (H&E) staining and immunohistochemistry. Then 4T1 cells were injected via tail vein. Lung surface metastasis was counted and detected by histological analysis. LPS-induced E-selectin expression and tumor cells adhesion were assessed by western blotting and immunofluorescence. The circulating levels of proinflammatory cytokines in sera were evaluated by ELISA. Our results showed that a significant increase in breast cancer metastasis to lungs was observed in LPS-treated mice vs. the PBS-treated mice, accompanying with an increased E-selectin expression in pulmonary tissue of LPS-treated mice. In vitro studies showed a significant elevation of E-selectin production in MPVECs which enhanced the adhesion activity of 4T1 cells. Treatment with anti-E-selectin antibody significantly reduced the development of metastasis in vivo, and significantly reduced the adhesion of 4T1 cells to MPVECs in vitro. Our results suggest that systemic inflammation may increase the expression of E-selectin which mediated the lung metastasis of breast cancer in mouse model.  相似文献   
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BackgroundEmerging evidence indicates that MCL has increased angiogenesis within the tumor microenvironment. We initiated a phase II trial to determine if the addition of bevacizumab to the standard R-CHOP regimen could enhance antitumor effects in patients with previously untreated MCL.Patients and MethodsEleven patients with previously untreated MCL received bevacizumab at 15 mg/kg on day 1, and standard CHOP-21 (CHOP given every 21 days per cycle) with rituximab (375 mg/m2 per cycle) on day 3 of each cycle for a total of 6 cycles. Planned study end points included safety and efficacy assessment, and exploratory analysis of angiogenic profiles. The study was suspended in August of 2010 based on safety findings in DLBCL (diffuse large B-cell lymphoma) of increased cardiovascular events with the regimen.ResultsBeyond the standard R-CHOP safety profile, Grade 3 left ventricular dysfunction developed in 2 patients (18%), Grade 1/2 hypertension, proteinuria, and bleeding each developed in 1 patient (9%). The overall response rate was 82% with 36% complete response (CR)/complete response unconfirmed (CRu). The median progression-free survival (n = 11) was 18 months (95% confidence interval, 3-not reached), and 3-year overall survival rate was 82%. Correlative studies showed increased vascular endothelial growth factor receptor 1 expression in tumor cells at baseline, and elevated levels of plasma vascular endothelial growth factor (VEGF) throughout treatment.ConclusionThe addition of bevacizumab to the standard R-CHOP regimen did not appear to significantly improve efficacy beyond that observed from previous studies using R-CHOP alone. Therapeutic strategies that provide sustained inhibition on VEGF-related and VEGF-independent targets within the tumor microenvironment might further improve antiangiogenic effects and warrant further exploration in MCL.  相似文献   
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The tumour microenvironment consists of a complex mixture of non‐neoplastic cells, including fibroblasts, immune cells and endothelial cells embedded in the proteins of the extracellular matrix. The tumour microenvironment plays an active role in tumour behaviour. By interacting with cancer cells, it influences disease progression and the metastatic capacity of the tumour. Tumours with a high amount of stroma correspond to poor patient prognosis. The tumour–stroma ratio (TSR) is a strong independent prognostic tool in colon cancer and provides additional value to the current clinically used tumour–node–metastasis classification. The TSR is assessed on conventional haematoxylin and eosin‐stained paraffin sections at the invasive front of the tumour. Here we review studies demonstrating the prognostic significance of the TSR in solid epithelial tumours with a focus on colon cancer. Moreover, the biological role of the tumour microenvironment during tumour progression and invasion will be discussed, as well as the attempts to target the tumour stroma for therapeutic purposes. We suggest that the TSR can be implemented with little effort and without additional costs in current routine pathology diagnostics owing to its simplicity and reliability.  相似文献   
45.
Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of-function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment.  相似文献   
46.
食管癌是恶性程度高、侵袭能力强、预后较差的一类上消化道恶性肿瘤,属中医学“噎膈”范畴。中药复方在抗肿瘤方面具有显著优势。通过查阅国内外相关文献,获知构成食管癌(噎膈)的证素包括气滞、痰、气虚、血瘀、阴虚等,中医临床辨证多分为痰气交阻、气阴两虚、津亏热结、气虚痰湿、痰热互结、痰瘀互结、热毒瘀结、正虚毒蕴等,大半夏汤、启膈散、旋覆代赭汤、六君子汤、沙参麦冬汤、通幽汤等为临床常用方剂,其中启膈散、六君子汤、通幽汤等经体内外实验研究已证明可通过直接抑制肿瘤细胞增殖、或促进凋亡、影响肿瘤微环境、调节细胞能量代谢、抑制血管生成等机制发挥抗食管癌作用,且中药复方通过靶向非编码单链RNA分子(microRNA)发挥抗食管癌作用的研究越来越多,发现临床收效良好的复方大半夏汤、参赭培气汤、小陷胸汤、人参半夏汤、六神丸等尚无深入的机制研究,古籍所载的吴茱萸汤、通关散等复方却于现代少有应用。因此,该文将中医经典古籍中专药专方、现代临床常用复方及实验研究进行梳理,以期推广中药复方抗食管癌的治疗方法,发挥中西医结合治疗的协同优势。  相似文献   
47.
外泌体是一种双层脂质膜连接囊泡样小体,存在于各种体液中,参与细胞及肿瘤微环境之间的物质运输和信号传递。外泌体含有多种生物活性分子,包括脂质、蛋白质、DNA、mRNA以及非编码RNA,可以通过这些活性分子影响肿瘤的发生和发展,甚至可以影响肿瘤的治疗。胰腺癌是一种常见的恶性肿瘤,侵袭性强,预后较差,死亡率高。胰腺癌来源的外泌体是胰腺肿瘤微环境中的重要组成部分,促使胰腺癌细胞成功逃避细胞凋亡的重要因素,并且可以促进肝脏转移微环境的形成。近年来,与胰腺癌相关的外泌体逐渐成为新的研究热点,研究发现外泌体有望成为早期胰腺癌筛查的新型生物学标志,并将为胰腺癌靶向治疗提供可行的技术基础。  相似文献   
48.
The tumor stroma is no longer seen solely as physical support for mutated epithelial cells but as an important modulator and even a driver of tumorigenicity. Within the tumor stromal milieu, heterogeneous populations of fibroblast-like cells, collectively termed carcinoma-associated fibroblasts (CAFs), are key players in the multicellular, stromal-dependent alterations that contribute to malignant initiation and progression. This review focuses on novel insights into the contributions of CAFs to disease progression, emergent events leading to the generation of CAFs, identification of CAF-specific biomarkers predictive of disease outcome, and recent therapeutic approaches aimed at blunting or reverting detrimental protumorigenic phenotypes associated with CAFs.  相似文献   
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PurposeAlthough skin cutaneous melanoma (SKCM) is a relatively immunotherapy-sensitive tumor type, there is still a certain fraction that benefits less from treatment. Ferroptosis has been demonstrated to modulate tumor progression in many cancer types. This study focused on ferroptosis-related genes to construct a prognostic model for SKCM patients.Materials and methodsGene expression profiles of SKCM samples were obtained from public databases. Unsupervised consensus clustering was used to determine molecular subtypes related to ferroptosis. Least absolute shrinkage and selection operator (LASSO) and stepwise Akaike information criterion (stepAIC) were applied to construct a prognostic model based on differentially expressed genes between two molecular subtypes.ResultsC1 and C2 subtypes were identified with differential prognosis and immune infiltration. A 7-gene prognostic model was constructed to classify samples into high-FPRS and low-FPRS groups. Low-FPRS group with favorable prognosis had higher immune infiltration and more enriched immune-related pathways than the high-FPRS group. The two groups showed distinct sensitivity to immunotherapy, with the low-FPRS group predicted to have more positive response to immunotherapy than the high-FPRS group. A nomogram based on the FPRS score and clinical features was built for more convenient use.ConclusionsThe critical role of ferroptosis involved in SKCM development was further validated in this study. The prognostic model was efficient and stable to be applied in clinical conditions to support clinicians in determining personalized therapy for SKCM patients especially those with metastasis.  相似文献   
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