RNA-Seq Signatures Normalized by mRNA Abundance Allow Absolute Deconvolution of Human Immune Cell Types

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Relationship between Tumor Cell Invasiveness and Polyploidization

A number of studies have shown that tumor cells fuse with other tumor and non-tumor cells. In the present study on tumor cell lines derived from glioblastoma, breast cancer, and melanoma, we estimated the frequency of fusion between tumor cells by establishing the fraction of cells with whole tumor-genome duplication in each cell line. Together with this, the capacity of the tumor cell lines to spread through a basement membrane scaffold was assessed, in order to test the hypothesis that pericellular proteolysis by enzymatic release in the spaces of intercellular contact could account for differences in the fusogenicity of tumor cells. The difference in invasiveness between the cell lines accounted for their specific amount of cells with tumor-genome duplication, which, depending on the cell line analyzed, ranged from 2% to 25% of the total cells. These results support the hypothesis that cell-to-cell invasion eliciting membrane fusion causes polyploidization in tumor cells.     

危重病人预警蛋白质组指纹与肿瘤患者生存关系的报告

目的:探讨危重病人预警蛋白质(lost goodwill target,LGT)多肽谱指纹的峰型和丰度对判断肿瘤患者病情发展及预后的意义.方法:对接受SELDI(Surface enhanced laser desorption/ionization-time of flight-mass spectrometer)技术检测的178名患者生存期与死亡时间进行调查,并根据SELDI检测所获得的指纹图中,以LGT指纹存在与否,分成无峰组、单峰组、双峰组、三峰和多峰组.采用多因素方差分析和COX风险回归模型分析的方法,比较四组中哪一种状态下死亡风险最大.结果:恶性肿瘤患者经SELDI技术检测所获取的指纹图中,如果LGT呈阴性表达,死亡风险低于单、双峰组,远低于三峰和多峰组;LGT呈三峰和多峰表达,其死亡风险远高于单、双峰组,差异有统计学意义(P<0.05),死亡率极高.结论:采用SELDI技术检测肿瘤患者的血清,LGT出现三峰和多峰表达,提示肿瘤患者病情即将恶化,该指纹标识为LGT阳性指标;单、双峰者为疑似指标;LGT指纹阴性表达,肿瘤患者近期预后良好,死亡风险极小.     

Immune Cell Types and Secreted Factors Contributing to Inflammation-to-Cancer Transition and Immune Therapy Response

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Overnight Resting of PBMC Changes Functional Signatures of Antigen Specific T- Cell Responses: Impact for Immune Monitoring within Clinical Trials

Polyfunctional CD4 or CD8 T cells are proposed to represent a correlate of immune control for persistent viruses as well as for vaccine mediated protection against infection. A well-suited methodology to study complex functional phenotypes of antiviral T cells is the combined staining of intracellular cytokines and phenotypic marker expression using polychromatic flow cytometry. In this study we analyzed the effect of an overnight resting period at 37°C on the quantity and functionality of HIV-1, EBV, CMV, HBV and HCV specific CD4 and CD8 T-cell responses in a cohort of 21 individuals. We quantified total antigen specific T cells by multimer staining and used 10-color intracellular cytokine staining (ICS) to determine IFNγ, TNFα, IL2 and MIP1β production. After an overnight resting significantly higher numbers of functionally active T cells were detectable by ICS for all tested antigen specificities, whereas the total number of antigen specific T cells determined by multimer staining remained unchanged. Overnight resting shifted the quality of T-cell responses towards polyfunctionality and increased antigen sensitivity of T cells. Our data suggest that the observed effect is mediated by T cells rather than by antigen presenting cells. We conclude that overnight resting of PBMC prior to ex vivo analysis of antiviral T-cell responses represents an efficient method to increase sensitivity of ICS-based methods and has a prominent impact on the functional phenotype of T cells.     

Increased Tumor Glycolysis Characterizes Immune Resistance to Adoptive T Cell Therapy

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肿瘤坏死因子alpha与子痫前期的关系

子痫前期是妊娠期特有疾病,是导致孕产妇及围生儿病死率的重要原因,其病因和发病机理仍未完全明确。目前,已被提出 和子痫前期的发生相关的因素包括遗传、氧化应激、异常滋养层细胞侵入、血管内皮细胞功能紊乱、营养缺乏、免疫缺陷等,其中 内皮细胞损伤导致的内皮细胞生理功能紊乱已经成为子痫前期病因学研究的热点。肿瘤坏死因子-alpha(tumor necrosis factor-alpha, TNF-alpha)在内皮细胞损害中发挥着重要作用,可能通过诱导炎性因子和血管内皮细胞黏附分子-1(VCAM-1)生成、抑制基质金属蛋 白酶(MMP)、影响血管活性物质、脂联素、瘦素和血管因子生成,介导子痫前期的发生。本文就TNF-琢与子痫前期发生的关系进行 综述。     

间充质干细胞与肿瘤的关系

最近的研究表明问充质干细胞(mesenchymal stem cells,MSCs)与多种肿瘤的发生发展有密切关系.MSCs对多种肿瘤具有趋向性,外源性(局部混合注射或静脉注射)MSCs可参与肿瘤间质的形成,同时MSCs的免疫抑制作用可以促进肿瘤在体内的生长.通过细胞因子介导或直接的细胞接触,MSCs与多种肿瘤细胞之间存在相互作用.MSCs可以抑制肿瘤细胞的的凋亡,促进肿瘤细胞的增殖及肿瘤的转移.由于MSCs易于分离、体外扩增及进行基因修饰,因此可以利用MSCs对肿瘤的趋向性,使MSCs携带抗肿瘤基因来实现对肿瘤的靶向治疗.     

Immune Checkpoint Blockade to Improve Tumor Infiltrating Lymphocytes for Adoptive Cell Therapy

Tumor-infiltrating lymphocytes (TIL) has been associated with improved survival in cancer patients. Within the tumor microenvironment, regulatory cells and expression of co-inhibitory immune checkpoint molecules can lead to the inactivation of TIL. Hence, there is a need to develop strategies that disrupt these negative regulators to achieve robust anti-tumor immune responses. We evaluated the blockade of immune checkpoints and their effect on T cell infiltration and function. We examined the ability of TIL to induce tumor-specific immune responses in vitro and in vivo. TIL isolated from tumor bearing mice were tumor-specific and expressed co-inhibitory immune checkpoint molecules. Administration of monoclonal antibodies against immune checkpoints led to a significant delay in tumor growth. However, anti-PD-L1 antibody treated mice had a significant increase in T cell infiltration and IFN-γ production compared to other groups. Adoptive transfer of in vitro expanded TIL from tumors of anti-PD-L1 antibody treated mice led to a significant delay in tumor growth. Blockade of co-inhibitory immune checkpoints could be an effective strategy to improve TIL infiltration and function.     

The Relationship between Muscle Fiber Type-Specific PGC-1α Content and Mitochondrial Content Varies between Rodent Models and Humans

PGC-1α regulates critical processes in muscle physiology, including mitochondrial biogenesis, lipid metabolism and angiogenesis. Furthermore, PGC-1α was suggested as an important regulator of fiber type determination. However, whether a muscle fiber type-specific PGC-1α content exists, whether PGC-1α content relates to basal levels of mitochondrial content, and whether such relationships are preserved between humans and classically used rodent models are all questions that have been either poorly addressed or never investigated. To address these issues, we investigated the fiber type-specific content of PGC-1α and its relationship to basal mitochondrial content in mouse, rat and human muscles using in situ immunolabeling and histochemical methods on muscle serial cross-sections. Whereas type IIa fibers exhibited the highest PGC-1α in all three species, other fiber types displayed a hierarchy of type IIx>I>IIb in mouse, type I = IIx> IIb in rat, and type IIx>I in human. In terms of mitochondrial content, we observed a hierarchy of IIa>IIx>I>IIb in mouse, IIa >I>IIx> IIb in rat, and I>IIa> IIx in human skeletal muscle. We also found in rat skeletal muscle that type I fibers displayed the highest capillarization followed by type IIa >IIx>IIb. Finally, we found in human skeletal muscle that type I fibers display the highest lipid content, followed by type IIa>IIx. Altogether, our results reveal that (i) the fiber type-specific PGC-1α and mitochondrial contents were only matched in mouse, (ii) the patterns of PGC-1α and mitochondrial contents observed in mice and rats do not correspond to that seen in humans in several respects, and (iii) the classical phenotypes thought to be regulated by PGC-1α do not vary exclusively as a function of PGC-1α content in rat and human muscles.     

血管生成拟态和肿瘤的关系

血管生成拟态指由恶性肿瘤细胞而非血管内皮细胞连接形成的、能为肿瘤提供血供的管网状结构．存在于恶性黑素瘤、卵巢癌、前列腺癌、炎性乳腺癌和某些软组织肉瘤。其发生和肿瘤细胞呈现出多潜能的胚胎样表型有关。进一步研究血管生成拟态的分子机制,探索有效的拮抗其过程的方案,有可能提供一种能有效治疗肿瘤、并且对正常生理过程的影响较小的策略     

Targeting A20 Decreases Glioma Stem Cell Survival and Tumor Growth

Glioblastomas are deadly cancers that display a functional cellular hierarchy maintained by self-renewing glioblastoma stem cells (GSCs). GSCs are regulated by molecular pathways distinct from the bulk tumor that may be useful therapeutic targets. We determined that A20 (TNFAIP3), a regulator of cell survival and the NF-κB pathway, is overexpressed in GSCs relative to non-stem glioblastoma cells at both the mRNA and protein levels. To determine the functional significance of A20 in GSCs, we targeted A20 expression with lentiviral-mediated delivery of short hairpin RNA (shRNA). Inhibiting A20 expression decreased GSC growth and survival through mechanisms associated with decreased cell-cycle progression and decreased phosphorylation of p65/RelA. Elevated levels of A20 in GSCs contributed to apoptotic resistance: GSCs were less susceptible to TNFα-induced cell death than matched non-stem glioma cells, but A20 knockdown sensitized GSCs to TNFα-mediated apoptosis. The decreased survival of GSCs upon A20 knockdown contributed to the reduced ability of these cells to self-renew in primary and secondary neurosphere formation assays. The tumorigenic potential of GSCs was decreased with A20 targeting, resulting in increased survival of mice bearing human glioma xenografts. In silico analysis of a glioma patient genomic database indicates that A20 overexpression and amplification is inversely correlated with survival. Together these data indicate that A20 contributes to glioma maintenance through effects on the glioma stem cell subpopulation. Although inactivating mutations in A20 in lymphoma suggest A20 can act as a tumor suppressor, similar point mutations have not been identified through glioma genomic sequencing: in fact, our data suggest A20 may function as a tumor enhancer in glioma through promotion of GSC survival. A20 anticancer therapies should therefore be viewed with caution as effects will likely differ depending on the tumor type.     

SIRT1 and c-Myc Promote Liver Tumor Cell Survival and Predict Poor Survival of Human Hepatocellular Carcinomas

The increased expression of SIRT1 has recently been identified in numerous human tumors and a possible correlation with c-Myc oncogene has been proposed. However, it remains unclear whether SIRT1 functions as an oncogene or tumor suppressor. We sought to elucidate the role of SIRT1 in liver cancer under the influence of c-Myc and to determine the prognostic significance of SIRT1 and c-Myc expression in human hepatocellular carcinoma. The effect of either over-expression or knock down of SIRT1 on cell proliferation and survival was evaluated in both mouse and human liver cancer cells. Nicotinamide, an inhibitor of SIRT1, was also evaluated for its effects on liver tumorigenesis. The prognostic significance of the immunohistochemical detection of SIRT1 and c-Myc was evaluated in 154 hepatocellular carcinoma patients. SIRT1 and c-Myc regulate each other via a positive feedback loop and act synergistically to promote hepatocellular proliferation in both mice and human liver tumor cells. Tumor growth was significantly inhibited by nicotinamide in vivo and in vitro. In human hepatocellular carcinoma, SIRT1 expression positively correlated with c-Myc, Ki67 and p53 expression, as well as high á-fetoprotein level. Moreover, the expression of SIRT1, c-Myc and p53 were independent prognostic indicators of hepatocellular carcinoma. In conclusion, this study demonstrates that SIRT1 expression supports liver tumorigenesis and is closely correlated with oncogenic c-MYC expression. In addition, both SIRT1 and c-Myc may be useful prognostic indicators of hepatocellular carcinoma and SIRT1 targeted therapy may be beneficial in the treatment of hepatocellular carcinoma.     

The Relationship between Adiponectin and Left Ventricular Mass Index Varies with the Risk of Left Ventricular Hypertrophy

Background

Adiponectin directly protects against cardiac remodeling. Despite this beneficial effect, most epidemiological studies have reported a negative relationship between adiponectin level and left ventricular mass index (LVMI). However, a positive relationship has also been reported in subjects at high risk of left ventricular hypertrophy (LVH). Based on these conflicting results, we hypothesized that the relationship between serum adiponectin level and LVMI varies with the risk of LVH.

Methods

A community-based, cross-sectional study was performed on 1414 subjects. LVMI was measured by echocardiography. Log-transformed adiponectin levels (Log-ADPN) were used for the analysis.

Results

Serum adiponectin level had a biphasic distribution (an increase after a decrease) with increasing LVMI. Although Log-ADPN did not correlate with LVMI, Log-ADPN was modestly associated with LVMI in the multivariate analysis (β = 0.079, p = 0.001). The relationship between adiponectin level and LVMI was bidirectional according to the risk of LVH. In normotensive subjects younger than 50 years, Log-ADPN negatively correlated with LVMI (r = −0.204, p = 0.005); however, Log-ADPN positively correlated with LVMI in ≥50-year-old obese subjects with high arterial stiffness (r = 0.189, p = 0.030). The correlation coefficient between Log-ADPN and LVMI gradually changed from negative to positive with increasing risk factors for LVH. The risk of LVH significantly interacted with the relationship between Log-ADPN and LVMI. In the multivariate analysis, Log-ADPN was associated with LVMI in the subjects at risk of LVH; however, Log-ADPN was either not associated or negatively associated with LVMI in subjects at low risk of LVH.

Conclusion

Adiponectin level and LVMI are negatively associated in subjects at low risk of LVH and are positively associated in subjects at high risk of LVH. Therefore, the relationship between adiponectin and LVMI varies with the risk of LVH.     

腹泻与T细胞的免疫微生态关系

本文比较了人类轮状病毒(HRV)腹泻与不同人群的T细胞免疫微生态学关系。结果表明:(1)健康人能保持微生态平衡,粪便中未查见HRV,T细胞的总数和功能均正常。(2)HRV携带者也能维持微生态平衡,粪便中仅见少量HRV,T细胞的总数和功能基本正常,但活性T细胞率降低显著。(3)HRV腹泻患儿发生了微生态失调,粪便中查见大最的HRV,T细胞的总数和功能均显著降低。(4)其他腹泻患儿也发生了微生态失调,虽然在粪便中未查见HRV、沙门氏菌和志贺氏菌,但是T细胞的总数和功能也都显著降低。     

miR-451与人类肿瘤关系的研究进展

Micro RNAs(miRNA)是一类在转录后水平调控基因表达的小分子非编码RNAs,通过调节细胞的增殖、分化、凋亡使机体维一个动态平衡。近年来,大量研究表明许多miRNA可作为原癌基因或者抑癌基因参与肿瘤的发生、发展,进一步研究发现,通过检测和调控这些miRNA,可用于肿瘤的早期诊断和治疗。最近一系列研究发现miRNA-451(miR-451)在许多肿瘤中存在差异性表达,与这些肿瘤的发生、发展、治疗有着密切的联系。本文对人类肿瘤中miR-451表达、调控的相关研究做一综述,为miR-451在肿瘤的诊断、治疗及预后中的应用提供重要资料。     

Hsp70-2 is Required for Tumor Cell Growth and Survival

Heat shock protein 70 (Hsp70) family consists of at least eight chaperone proteins that differ from each other by their pattern of expression and intracellular localization. Whereas ample experimental and clinico-pathological data has implicated the major stress-inducible Hsp70-1 as a protein required for cancer cell survival, the study of the other family members has been limited by the lack of experimental tools to differentiate between the highly homologous family members. This limitation has been recently overcome by the RNA interference technology that for the first time allows targeted knockdown of the individual Hsp70 family members. Data based on this technology has revealed that also Hsp70-2, a protein essential for spermatogenesis, is required for cancer cell growth and survival. Remarkably, the highly homologous Hsp70 proteins enhance cancer cell growth and survival by distinct molecular mechanisms.     

The Tumor Cell and Telomerase

Imbalanced activity of the mechanism that controls cell division is a prerequisite for malignant transformation of a normal cell. The present review considers this multi-step mechanism, which is usually called the G1-S checkpoint. Besides, tumor cells are characterized by the presence of telomerase, an enzyme responsible for restoration of chromosome ends after replication and thus providing for unlimited cell division. The main point of the present article is to find out whether the activation of telomerase is controlled by the G1-S checkpoint or does not depend on it. The principal components of the G1-S checkpoint, such as cyclin-dependent kinases, retinoblastoma and E2F proteins, control the activity of telomerase. In their turn, they accumulate and transmit signals from various sources inside and outside the cell. Thus, various changes in tumor cells can activate telomerase through the G1-S checkpoint. Such are the suggested effects on telomerase of Myc, p53, Waf1, protein kinases B and C, Wnt5A, TGFbeta, WT1, and estrogens. However, Myc, p53, WT1, estrogens, protein kinases B and C, and TGFbeta can also directly influence telomerase independently of the G1-S checkpoint mechanism. Moreover, in 30% of human tumors the gene of the key subunit of telomerase (hTERT) is amplified, possibly due to chromosomal rearrangements unassociated with the activity of the G1-S checkpoint. Thus, telomerase seems to be activated not by a single agent but due to combined action of various factors, both with involvement of the G1-S checkpoint mechanism and independently of it.