胸腺基质淋巴细胞生成素对胃癌免疫微环境的影响

现阶段胃癌的主要治疗手段是以手术为主的综合治疗,鉴于我国患者仍以进展期胃癌为主,整体疗效及预后依然较差,胃癌治疗研究者还需要探索更多新的诊疗方式。近年来,对胃癌发生发展至关重要的肿瘤免疫微环境逐渐成为人们关注和研究的热点。胸腺基质淋巴细胞生成素（thymic stromal lymphopoietin,TSLP）是一种多功能细胞因子,能够作用于肿瘤微环境中的多种关键成分,促进诱导肿瘤细胞免疫逃逸的肿瘤免疫微环境的形成,有利于肿瘤的发生发展。对TSLP在胃癌免疫微环境中作用的研究可能为提升胃癌治疗效果提供一条新的途径。本文就TSLP对胃癌免疫微环境的影响作一综述。     

Systemic inflammation is associated with the density of immune cells in the tumor microenvironment of gastric cancer

Background

The neutrophil–lymphocyte ratio (NLR) and the prognostic nutritional index (PNI) are markers of systemic inflammation known to be useful prognostic indicators of malignancy. However, little evidence has defined the influence of inflammation on the tumor microenvironment.

Methods

Two hundred eighty-eight patients who underwent curative surgery for gastric cancer were included. Preoperative peripheral blood samples were used to analyze the NLR and PNI. The optimal cutoff levels for the NLR and PNI were defined by receiver operating characteristic curve analysis for survival (NLR = 2.7, PNI = 47.7). The densities of specific immune cells (CD3⁺, CD4⁺, CD8⁺) within the tumor microenvironment were measured in tumor microarrays by immunohistochemical analysis.

Results

Two hundred thirty-five patients (81.6 %) had a low NLR and 53 patients (18.4 %) had a high NLR. One hundred seventeen patients (40.6 %) had a low PNI and 171 patients (59.4 %) had a high PNI. CD3⁺ and CD8⁺ immune cell density were not associated with the NLR and PNI. However, in the high-NLR group compared with the low-NLR group, CD4⁺ immune cell density was significantly decreased (P < 0.001). Similarly, the density of CD4⁺ immune cells was also significantly decreased in the low-PNI group compared with the high-PNI group (P = 0.007). A high NLR and a low PNI were correlated with worse overall survival in multivariate analysis (P = 0.028 and P = 0.002 respectively).

Conclusions

The NLR and PNI are associated with the density of CD4⁺ immune cells in the tumor microenvironment, which leads to prognostic values of systemic inflammation in gastric cancer.

     

Cellular constituents of immune escape within the tumor microenvironment

Established tumors are complex masses that contain not only neoplastic cells but also nontransformed cellular elements such as stromal cells, the neovasculature, and the full gamut of immune cells. However, evidence suggests that, unlike cells found in lymphoid organs that productively respond to acute infections, immune cells in tumors are dysregulated and functionally impaired. Tumor masses can contain regulatory lymphocytes, myeloid-derived suppressor cells, alternatively activated macrophages, and dendritic cells. Ablation or reprogramming of this aberrant microenvironment might dramatically augment cancer therapies, and this strategy is currently being deployed in a variety of clinical trials. A better understanding of the cellular constituents of tumors and the mechanisms involved in immune evasion may help guide the next generation of innovative cancer immunotherapies.     

A novel mouse model of gastric cancer with human gastric microenvironment

Mouse models play an irreplaceable role in the in vivo research of human gastric cancer. In this study, we developed a novel human Gastric tissue-derived Orthotopic and Metastatic (GOM) mouse model of human gastric cancer, in which the human normal gastric tissues were implanted subcutaneously into immunodeficient mice to create a human gastric microenvironment. Then, human gastric cancer cells were injected into the implants. GOM model could mimic the interactions between human gastric microenvironment and human gastric cancer cells, which help exhibit the real characteristics of tumor cells, and finally mimic the clinical-like tumor proliferation and metastases of human beings.     

Immune cell infiltration as an indicator of the immune microenvironment of pancreatic cancer

Background:

The host immune reaction is represented by immune/inflammatory cell infiltrates. Here we systematically analysed tumour-infiltrating immune/inflammatory cells in pancreatic ductal carcinoma (PDC) and evaluated their clinicopathological impact.

Methods:

Using immunohistochemistry, we examined tumour-infiltrating CD68⁺ pan-macrophages, HLA-DR⁺CD68⁺ M1 macrophages (M1), CD163⁺ or CD204⁺ M2 macrophages (M2), CD66b⁺ neutrophils (Neu), CD4⁺ T cells (CD4⁺T), CD8⁺ T cells (CD8⁺T), and FOXP3⁺CD4⁺ regulatory T cells (Treg) in 212 cases of PDC, and conducted correlation and survival analyses using the Kaplan–Meier method and Cox proportional hazards model.

Results:

Higher levels of tumour-infiltrating pan-macrophages, M2, Neu, or the ratio of Tregs to CD4⁺T (%Treg) were significantly associated with shorter survival, whereas higher levels of tumour-infiltrating CD4⁺T, CD8⁺T, or the ratio of M1 to pan-macrophages (%M1) were significantly associated with longer survival. Survival analysis of pairs of these variables revealed that some of the resulting patient groups had exclusively longer survival. We then connected the apparently related factors, and two significant variables emerged: tumour-infiltrating CD4⁺T^high/CD8⁺T^high/%Treg^low and tumour-infiltrating %M1^high/M2^low. Multivariate survival analysis revealed that these variables were significantly correlated with longer survival and had a higher hazard ratio.

Conclusion:

Tumour-infiltrating CD4⁺T^high/CD8⁺T^high/%Treg^low and %M1^high/M2^low are independent prognosticators useful for evaluating the immune microenvironment of PDC.     

miR-132 upregulation promotes gastric cancer cell growth through suppression of FoxO1 translation

Tumor Biology - Gastric carcinoma (GC) is a prevalent malignant cancer worldwide and is highly lethal due to its fast growth. Hence, treatments to suppress GC cell growth may be applied together...     

Clinical significance of immune cell infiltration within gallbladder cancer

To investigate the pathophysiological significance of infiltrating antitumour immune cells, we evaluated the quantity of immune cell intratumoral infiltration in 110 surgically resected gallbladder specimens by immunohistochemistry. We examined 45 cases of gallbladder cancer and 65 cases of benign gallbladder diseases for CD4(+) T cells, CD8(+) T cells, natural killer cells (NKCs), and dendritic cells (DCs). High levels of CD4(+) T cell, CD8(+) T cell, NKC, and DC infiltration were recognised in 51.1% (23 out of 45), 37.8% (17 out of 45), 33.3% (15 out of 45), and 48.9% (22 out of 45) of cancer specimens, respectively. High numbers of infiltrating CD4(+) and CD8(+) T cells correlated with decreasing tumour invasion, and high numbers of infiltrating DCs correlated with decreasing lymph-node tumour metastasis. Furthermore, increased infiltration of CD4(+) and CD8(+) T cells and DCs exhibited a significant correlation with prolonged survival. NKC infiltration, however, did not correlate with any of the clinicopathological factors examined. Additionally, high levels of infiltration were not identified in specimens from benign diseases, consistent with the cancer-specific activity of CD4(+) and CD8(+) T cells and DCs. In this study, we demonstrate that CD4(+) and CD8(+) tumour-infiltrating lymphocyte and DCs, but not NKCs, are important factors in the accurate prognosis of survival after surgical removal of gallbladder adenocarcinoma.     

Hereditary diffuse gastric cancer: association with lobular breast cancer

Hereditary diffuse gastric cancer (HDGC) has been shown to be caused by germline mutations in the gene CDH1 located at 16q22.1, which encodes the cell–cell adhesion molecule, E-cadherin. Not only does loss of expression of E-cadherin account for the morphologic differences between intestinal and diffuse gastric cancer (DGC) variants, but it also appears to lead to distinct cellular features which appear to be common amongst related cancers that have been seen in the syndrome. As in most hereditary cancer syndromes, multiple organ sites may be commonly affected by cancer, in HDGC, lobular carcinoma of the breast (LBC) and possibly other organ sites have been shown to be associated with the familial cancer syndrome. Given the complexity of HDGC, not only with regard to the management of the DGC risk, but also with regard to the risk for other related cancers, such as LBC, a multi-disciplinary approach is needed for the management of individuals with known CDH1 mutations.     

Heterogeneity in the immune microenvironment of bone metastasis in driver-positive non-small cell lung cancer

Mutations in epidermal growth factor receptor and anaplastic lymphoma kinase are common driver events in non-small cell lung cancer (NSCLC), which are associated with a high frequency of bone metastases (BMs). While the bone marrow represents a specialized immune microenvironment, the immune repertoire of BMs remains unknown. Considering the higher incidence of BMs in driver gene-positive NSCLCs, and the unique biology of the bone, herein, we assessed the infiltrating immune cells and T cell receptor (TCR) profile of BMs in driver-positive NSCLCs. Immune profile of BMs in driver gene-positive NSCLC were assessed in 10 patients, where 6 had driver gene-positive mutation. TCR and bulk RNA sequencing were performed on malignant bone samples. The diversity and clonality of the TCR repertoire were analyzed. The cellular components were inferred from bulk gene expression profiles computationally by CIBERSORT. Although BMs were generally regarded as immune-cold tumors, immune cell composition analyses showed co-existence of cytotoxic and suppressor immune cells in driver-positive BM samples, as compared to primary lung. Analysis of the TCR repertoire indicated a trend of higher diversity and similar clonality in the driver-positive compared with the driver-negative subsets. In addition, we identified two cases that showed the opposite response to immune checkpoint blockade. A comparison of these two patients' BM samples showed more highly amplified clones, fewer M2 macrophages and more activated natural killer cells in the responder. In summary, BMs in NSCLC are heterogeneous in their immune microenvironment, which might be related to differential clinical outcomes to immune checkpoint blockade.     

Proteomic profiling of gastric cancer with peritoneal metastasis identifies a protein signature associated with immune microenvironment and patient outcome

Background

Peritoneal metastasis (PM) frequently occurs in patients with gastric cancer (GC) and is a major cause of mortality. Risk stratification for PM can optimize decision making in GC treatment.

Methods

A total of 25 GC patients (13 with synchronous, 6 with metachronous PM and 6 PM-free) were included in this study. Quantitative proteomics by high-depth tandem mass tags labeling and whole-exome sequencing were conducted in primary GC and PM samples. Proteomic signature and prognostic model were established by machine learning algorithms in PM and PM-free GC, then validated in two external cohorts. Tumor-infiltrating immune cells in GC were analyzed by CIBERSORT.

Results

Heterogeneity between paired primary and PM samples was observed at both genomic and proteomic levels. Compared to primary GC, proteome of PM samples was enriched in RNA binding and extracellular exosomes. 641 differently expressed proteins (DEPs) between primary GC of PM group and PM-free group were screened, which were enriched in extracellular exosome and cell adhesion pathways. Subsequently, a ten-protein signature was derived based on DEPs by machine learning. This signature was significantly associated with patient prognosis in internal cohort and two external proteomic datasets of diffuse and mixed type GC. Tumor-infiltrating immune cell analysis showed that the signature was associated with immune microenvironment of GC.

Conclusions

We characterized proteomic features that were informative for PM progression of GC. A protein signature associated with immune microenvironment and patient outcome was derived, and it could guide risk stratification and individualized treatment.

     

非小细胞肺癌组织免疫微环境的特点及其临床意义

目的：探讨基于非小细胞肺癌（non-small cell lung cancer,NSCLC）患者原发灶组织中程序性死亡受体-配体1（programmed death-ligand 1,PD-L1）表达和间质中CD8+T细胞浸润的免疫微环境分型的特点及其临床意义。方法:回顾性分析2016年1 月到2018 年7 月空军特色医学中心收治的74 例NSCLC患者的石蜡组织标本及临床病理资料,所有患者均有EGFR基因检测结果、未接受放化疗及靶向治疗。采用免疫组化方法检测组织中PD-L1 表达及间质中CD8+T细胞浸润,分别分析PD-L1、CD8+T细胞及基于两者的免疫微环境分型与病理参数和患者生存的关系。结果:NSCLC患者原发灶组织中PD-L1 表达在不同性别、病理类型、吸烟史、EFGR突变组中有明显差异（均P<0.05）,CD8+T细胞浸润在不同TNM分期、淋巴结转移组织各组中有明显差异（均P<0.05）;PD-L1 表达与EGFR突变显著相关（P=0.000）,而CD8+T细胞浸润与EGFR突变不相关（P=0.605）。EGFR野生型患者免疫微环境以CD8+ PD-L1（+ Ⅰ型）为主、突变型以CD8- PD-L1（- Ⅱ型）及CD8+ PD-L1（- Ⅳ型）为主。免疫微环境分型在不同EGFR突变、吸烟史、病理分化程度的各组中分布有明显差异（均P<0.05）,且与EGFR突变显著相关（P<0.05）。随访显示处于无病生存期、复发转移和死亡患者中分别以Ⅰ型、Ⅱ型和Ⅰ型最多。结论:本组NSCLC患者肿瘤免疫微环境分型分布主要以Ⅰ型最多、Ⅲ型最少,其分型与EGFR突变、吸烟史及病理分化有关;EGFR突变患者以CD8+ PD-L1（- Ⅱ）型和CD8+ PD-L1（- Ⅳ型）为主,且与PD-L1低表达相关。     

Mechanisms of immune suppression in patients with head and neck cancer: Influence on the immune infiltrate of the cancer

Freshly excised human head and neck cancers (219 primary cancers; 64 metastatic lymph node cancers) were analyzed for the immune inhibitory mediators released from the cancer tissues and the immune infiltrate within the tumor. Significant levels of the immune inhibitory mediators transforming growth factor-β (TGF-β), prostaglandin E₂ (PGE₂) and interleukin-10 (IL-10) were released from these cancers. Also released was granulocyte-macrophage colony-stimulating factor (GM-CSF), whose secretion was associated with an intratumoral presence of CD34⁺ cells. We have previously shown that CD34⁺ cells within human head and neck cancers are immune inhibitory granulocyte-macrophage progenitor cells. The presence of TGF-β, PGE₂ and IL-10 was associated with a reduced content of CD8⁺ T-cells within the cancers. The CD4⁺ cell content appeared to be less affected by these immune inhibitory mediators. Instead, parameters indicative of CD4⁺ cell function (p55 IL-2 receptor expression, release of IL-2 and IFN-γ) were diminished in cancers that released higher levels of TGF-β, IL-10 and GM-CSF and had a higher CD34⁺ cell content. Furthermore, metastatic cancers released higher levels of the soluble immune inhibitory mediators and lower levels of IFN-γ and IL-2 than did primary cancers, although CD34⁺ cells were similarly present in both primary and metastatic cancers. Our results show that human head and neck cancers have a multiplicity of non-mutually exclusive mechanisms of immune suppression that are most prominently associated with reduced CD8⁺ cell influx and reduced influx and altered function of intratumoral CD4⁺ cells. © 1996 Wiley-Liss, Inc.     

肺癌免疫微环境中的肿瘤相关巨噬细胞

随着对肿瘤免疫发生和免疫耐受认识的不断深入,肺癌免疫治疗成为研究的热点.肿瘤免疫微环境在肺癌的发生、发展、转移过程中起着重要作用.肿瘤相关巨噬细胞(TAM)是肺癌免疫微环境中白细胞的主要成分之一,TAM和肺癌的关系随着研究的深入而逐渐明确,TAM作为肺癌免疫治疗新的靶点成为可能.     

Role of exosomes in the immune microenvironment of ovarian cancer

Exosomes are excretory vesicles that can deliver a variety of bioactive cargo molecules to the extracellular environment. Accumulating evidence demonstrates exosome participation in intercellular communication, immune response, inflammatory response and they even play an essential role in affecting the tumor immune microenvironment. The role of exosomes in the immune microenvironment of ovarian cancer is mainly divided into suppression and stimulation. On one hand exosomes can stimulate the innate and adaptive immune systems by activating dendritic cells (DCs), natural killer cells and T cells, allowing these immune cells exert an antitumorigenic effect. On the other hand, ovarian cancer-derived exosomes initiate cross-talk with immunosuppressive effector cells, which subsequently cause immune evasion; one of the hallmarks of cancer. Exosomes induce the polarization of macrophages in M2 phenotype and induce apoptosis of lymphocytes and DCs. Exosomes further activate additional immunosuppressive effector cells (myeloid-derived suppressor cells and regulatory T cells) that induce fibroblasts to differentiate into cancer-associated fibroblasts. Exosomes also induce the tumorigenicity of mesenchymal stem cells to exert additional immune suppression. Furthermore, besides mediating the intercellular communication, exosomes carry microRNAs (miRNAs), proteins and lipids to the tumor microenvironment, which collectively promotes ovarian cancer cells to proliferate, invade and tumors to metastasize. Studying proteins, lipids and miRNAs carried by exosomes could potentially be used as an early diagnostic marker of ovarian cancer for designing treatment strategies.     

5-FU节拍化疗策略优化及调节胃癌免疫微环境的体内实验研究

背景与目的：5-氟尿嘧啶（5-fluorouracil,5-FU）是胃癌化疗的骨架药物,传统大剂量5-FU常导致严重不良反应及耐药。低剂量5-FU节拍化疗在不影响疗效的前提下可明显降低药物毒性,但何种给药节拍可达到最佳抗肿瘤作用尚不清楚。本研究旨在探索5-FU的最佳节拍化疗模式,并研究其对胃癌免疫微环境的影响。方法：建立SGC-7901胃癌细胞系的BALB/c裸小鼠皮下移植瘤模型,成瘤后随机分成4组：最大耐受剂量（maximumtolerateddose,MTD）组、每日节拍化疗（daily metronomic chemotherapy,MET-qd）组、隔日节拍化疗（every other day metronomic chemotherapy,MET-qod）组和每周2次节拍化疗（twice-weekly metronomic chemotherapy,MET-biw）组。21 d为1个疗程,共2个疗程。治疗期间观测裸小鼠的一般状况,每周称重并测量瘤体,绘制肿瘤生长曲线。采用流式细胞术检测裸小鼠外周血内皮祖细胞（circulating endothelialprogenitors...