脂代谢重编程调控免疫微环境抗肿瘤的研究进展北大核心CSCD

目前,激活宿主抗肿瘤免疫应答的免疫治疗是肿瘤治疗领域的热点。但脂代谢重编程介导的微环境免疫抑制仍阻碍着肿瘤免疫治疗的进展。肿瘤细胞为满足自身快速增殖的需求而改变生物合成方式及代谢信号,其代谢产物可通过多种方式影响免疫细胞的激活及抗肿瘤免疫应答的发生。本文将从微环境条件下肿瘤脂代谢产物对免疫微环境的影响及治疗进展进行综述,以期为抗肿瘤治疗提供新的发展思路。     

肿瘤免疫治疗的进展——靶向阻断负性免疫调节分子

肿瘤免疫治疗具有靶向抗肿瘤作用而成为人们研究的热点.然而,肿瘤细胞通过多种途径诱导“免疫豁免”效应,削弱免疫治疗的疗效.大量研究表明,在T细胞活化中,一些关键性负性免疫调节分子是肿瘤诱导免疫耐受的重要机制.因此,靶向阻断这些负性免疫调节分子在增强抗肿瘤免疫应答中具有重要意义.     

树突状细胞肿瘤疫苗的研究进展

在抗肿瘤免疫应答中,关键的一步是抗原呈递细胞将肿瘤抗原呈递给T淋巴细胞。树突状细胞是专职抗原呈递细胞,它能够有效的将肿瘤抗原呈递给T细胞,引发机体产生抗肿瘤的免疫应答。因此,利用树突状细胞制备肿瘤疫苗可望提供一种有效的肿瘤免疫治疗方法。目前,体外实验、动物实验和初期的临床实验都已经证明了树突状细胞肿瘤疫苗的抗肿瘤作用。本文主要介绍树突状细胞的生物学特征和树突状细胞肿瘤疫苗在肿瘤免疫治疗中的研究进展。     

028 树突状细胞与特异性肿瘤免疫治疗

树突状细胞(DC)是体内功能最强的抗原提呈细胞(APC),也是抗原特异性免疫应答的始动者,由DC激活的T细胞介导的免疫应答在机体抗肿瘤过程中起着主导作用.本文主要对DC参与抗肿瘤的机制、DC与肿瘤免疫逃逸的关系及近年来DC在肿瘤生物治疗方面的研究进展作一综述.以DC为基础的肿瘤治疗主要有两种方式①免疫治疗肿瘤抗原体外冲击致敏DC后回输体内;②基因治疗以目的基因转染DC后回输体内.     

基于打破树突状细胞耐受的抗肿瘤免疫治疗

树突状细胞(DC)是专职抗原呈递细胞,具有强大的免疫监视功能.由于在诱导免疫反应中的重要作用,DC已被广泛地应用于抗肿瘤免疫治疗.但是由于肿瘤细胞对荷瘤宿主免疫系统,尤其是对DC功能的抑制,使以DC为基础的抗肿瘤免疫治疗疗效受到了很大的限制.所以,通过调节DC功能,可打破肿瘤对DC的免疫抑制,引导有效的抗肿瘤反应,提高以DC为基础的抗肿瘤免疫效果,这在抗肿瘤免疫治疗中具有重要意义.     

纳米载药系统在肿瘤靶向免疫治疗中的研究进展

<正>肿瘤的免疫治疗系指向肿瘤患者输注具有抗肿瘤活性的免疫细胞或抗体,直接杀伤肿瘤或激发机体抗肿瘤免疫应答来治疗肿瘤的生物疗法。肿瘤免疫治疗由于其较低的毒性和较高的特异性,被认为是一种很有潜力的治疗手段~([1-2])。随着对肿瘤学和免疫学研究的深入,肿瘤的免疫治疗逐渐成为继手术治疗、放疗、化疗的又一大新型治疗方式。为进一步加强肿瘤免疫治疗效果、降低药物的副作用,相关研究人员不断探索并研究了一系列具有肿瘤免疫治疗作用的新型     

逆转T 细胞耗竭在肿瘤免疫治疗中研究进展

近年来随着肿瘤免疫治疗的深入研究,PD-1/PD-L1免疫抑制剂在临床试验及临床实际抗肿瘤应用中取得突破性进展,但仍有临床耐药及部分患者无效的问题,PD-1/PD-L1免疫抑制剂抗肿瘤机制主要为改善抗肿瘤免疫应答,逆转T细胞耗竭,增强T细胞抗肿瘤免疫反应。本文以逆转T细胞耗竭最新研究及进展应用于肿瘤免疫治疗作一综述,为临床治疗提供参考。     

干扰素介导肿瘤免疫分子机制的研究进展

干扰素(IFNs)是一类具有多种生物活性的细胞因子,在肿瘤微环境中调节细胞免疫和体液免疫,发挥重要的抗病毒和抗肿瘤免疫作用.免疫治疗已成为肿瘤手术治疗及放化疗之后的重要治疗方式,但在某些肿瘤中,免疫治疗的作用效果甚微,其原因可能是耐药及免疫逃逸,因此探究肿瘤免疫逃逸的具体机制意义重大.     

调节性T细胞介导的肿瘤免疫耐受

恶性肿瘤能够有效的逃避免疫系统的监视源于免疫反应系统功能的障碍,多种因素都可导致抗肿瘤免疫的失效.调节性T细胞(Tr)在肿瘤浸润的淋巴细胞及肿瘤引流的淋巴结中高频出现,意味着其能促进肿瘤生长.Tr在肿瘤免疫病理以及调节免疫治疗的效果中起重要作用.因此,肿瘤患者的Tr可能成为重要的治疗靶细胞,并将会为抗肿瘤免疫治疗提供新策略.     

树突状细胞与特异性肿瘤免疫治疗

树突状细胞 (DC)是体内功能最强的抗原提呈细胞 (APC) ,也是抗原特异性免疫应答的始动者 ,由DC激活的T细胞介导的免疫应答在机体抗肿瘤过程中起着主导作用。本文主要对DC参与抗肿瘤的机制、DC与肿瘤免疫逃逸的关系及近年来DC在肿瘤生物治疗方面的研究进展作一综述。以DC为基础的肿瘤治疗主要有两种方式 :①免疫治疗 :肿瘤抗原体外冲击致敏DC后回输体内 ;②基因治疗 :以目的基因转染DC后回输体内     

Tumor microenvironment: hypoxia and buffer capacity for immunotherapy

In recent years, significant progress has been made in the study of tumor biology and anti-tumor immunotherapy. However, the cellular and molecular mechanisms of tumor progression still remain obscure. As we know, tumor microenvironment that can directly influence tumor development and prognosis has attracted much attention of large number of immunologists. Accumulated evidence has suggested that tumor microenvironment is in a hypoxic condition, under which immune cells may exhibit distinct functions compared to those under normal oxygen tension. The article we propose here will offer a novel point of view for understanding tumor microenvironment in order to instruct clinical immunotherapy. Just like the pH buffer system in human body, interactions of immune cells in tumor microenvironment may also constitute a buffer system, the balance of which is of great importance during immunotherapy for tumors. However, many protocols for tumor immunotherapy in clinic at present have not taken it into account, so the therapeutic outcome is often disappointing. In the present study, we have demonstrated the effect of Corynebacterium parvum, a well known immune stimulator, on malignant melanoma. Cell ingredients in tumor-infiltrating lymphocytes (TIL) and their anti-tumor effect have been altered when dosage of Corynebacterium parvum is changed. So, to obtain better therapeutic purposes, what we should do first is to detect an index to evaluate immune buffer capacity for the patient during tumor immunotherapy, then to choose appropriate drug doses to augment buffer capacity for their immune buffer system. Taken together, the hypothesis proposed here may help understand the pathogenesis of tumor progression and design more effective strategy for clinical immunotherapy for tumors.     

The cyclins: a family of widely expressed tumor antigens?

Continuous cell division is a hallmark of cancer and cell-cycle regulators therefore represent relevant target molecules for tumor therapy. Among these targets the cyclins are of particular interest as they are overexpressed in various tumor entities with little expression in normal tissue. Here we review evidence that these molecules are recognized by the immune system, summarize why cyclins A, B and D in particular appear to be interesting targets for active and passive immunotherapy, and discuss whether the entire family could be an interesting novel class of tumor antigens for cancer treatment and prevention.     

程序性死亡因子1及其配体在脑胶质瘤中的研究进展

脑胶质瘤一直是中枢神经系统肿瘤研究的重点及难点,高级别胶质瘤因其浸润生长快,位置特殊,综合治疗后效果并不理想。肿瘤免疫治疗通过维持肿瘤与免疫系统的平衡,恢复机体抗肿瘤免疫应答,从而限制肿瘤的发生、发展。目前免疫治疗已运用与多种实体瘤中,并取得了令人欣喜的结果,也为脑胶质瘤的治疗提供了新的思路。阻断PD-1/PD-L1是目前肿瘤免疫治疗的热点。本文就PD-1/PD-L1在脑胶质瘤中的研究及治疗进展进行综述。     

Cell-based vaccination against melanoma – background, preliminary results, and perspective

Melanoma is the prototype of a tumor to which many forms of immunotherapy have been applied extensively over the past two decades. Melanoma vaccines (active specific immunotherapy) are designed to modulate the immune system and have subsequent anti-tumor effects with minimal toxicity. Previous attempts to produce melanoma vaccines include immunization with whole tumor cells/cell lysates admixed with nonspecific adjuvants. While these vaccines generate enhanced anti-tumor immunity in a subset of patients, some of whom survive for longer than historical controls, no clinical benefit has so far been demonstrated in a properly controlled phase III study. Genetic modifications of tumor cells to make them express cytokines afford new-generation melanoma vaccines, and generate long-lasting systemic antitumor immunity in animal models. Translation of these preclinical results primarily into melanoma patients with advanced diseases shows the potential to induce systemic antitumor immune responses and in some instances tumor regression with acceptably low toxicity. The efficacy of this novel vaccine approach would be expected to be higher when used in a postsurgical adjuvant setting when the tumor load is small. Other novel vaccine approaches such as dendritic cell-based therapy also hold promise for the treatment of melanoma. The clinical value of all these new approaches will eventually have to be established in prospectively randomized clinical studies.     

Mechanism of tumor cells escaping from immune surveillance of NK cells

Abstract

Natural killer (NK) cells play an important role in anti-tumor and anti-infection, and perform their immune surveillance function in various ways. However, no matter what kind of cancer, the functional activity of NK cells in the tumor microenvironment (TME) is suppressed. Understanding the relationship between tumor cells and NK cells is very critical for tumor immunotherapy. This review discusses the mechanism of tumor cells escaping the immune surveillance of NK cells. These include a variety of factors that inhibit the activity of NK cells, an imbalance of activating receptors and inhibiting receptors on NK cells, abnormal binding of receptors and ligands, cross-talk of surrounding cell groups and NK cells in the TME, and other factors that affect NK cell activity. An understanding of these factors is necessary to provide new treatment strategies for tumor immunotherapy.     

Activation of benign autoimmunity as both tumor and autoimmune disease immunotherapy: A comprehensive review

Here, I consider how benign autoimmunity, the immunological homunculus, can be used to reinstate the healthy regulation of inflammation in both autoimmune diseases and in tumor immunotherapy. Different autoimmune diseases manifest clinically distinct phenotypes, but, in general, they all result from the transition of benign, healthy recognition of key body molecules into a damaging effector reaction. Tumors, in contrast to autoimmune diseases, grow by subverting the immune system into supporting and protecting the growing tumor from immune surveillance. Therefore our therapeutic aim in autoimmune disease is to induce the immune system to down-regulate the specific autoimmune effector reaction that causes the disease; in tumor immunotherapy, on the contrary, we aim to deprive the growing tumor of its illicit activation of immune suppression and to unleash an autoimmune disease targeted to the tumor. The recent success of anti-PD1 and anti-CTLR4 treatments exemplify the reinstatement of tumor autoimmunity subsequent to inhibition of immune suppression. With regard to the therapy of autoimmune diseases, I cite examples of immune system down-regulation of autoimmune diseases by T cell vaccination or HSP60 peptide treatment. Inducing the immune system to regulate itself is safer than global immune suppression and may be more effective in the long run.     

Cancer stem cells, CD200 and immunoevasion

The limited success seen in cancer immunotherapy signifies that an alternative approach is required. Advances in cancer biology have identified a biologically unique subpopulation of cells, termed cancer stem cells (CSC), that survive after conventional therapy. CSCs are the putative cancer-initiating cells responsible for tumor initiation, progression and metastasis. CSCs might be able to evade the immune system by generating a tolerogenic response facilitated by the immunosuppressive factor CD200. This article reviews the biological importance of CSCs and the potentially important role of CD200 in tumor immunology. Moreover, we discuss the prospective role CD200 plays in the ability of a CSC to escape the immune system. Future immunotherapy must consider targeting CSCs to achieve curative responses.     

减毒沙门菌作为新型肿瘤疫苗运送载体——癌症免疫治疗新希望

抗肿瘤免疫治疗是通过提高肿瘤特异性抗原的免疫原性及肿瘤细胞对效应性杀伤细胞的敏感性,调动机体免疫系统抵抗肿瘤细胞增殖和浸润的免疫治疗方法.与常规手术治疗、放射治疗和化学药物治疗相比,免疫治疗具有伤害小、毒性低等优点,但其在疫苗策略领域中的效果并不理想.近年来的研究表明,适当的载体有望显著提高疫苗的效果.减毒沙门菌是一种活疫苗载体,具有佐剂的作用,能够有效激活机体免疫细胞,在抗肿瘤免疫治疗中具有广阔的应用前景.     

Specificity in cancer immunotherapy

From the earliest days in the field of tumor immunology three questions have been asked: do cancer cells express tumor-specific antigens, does the immune system recognize these antigens and if so, what is their biochemical nature? We now know that truly tumor-specific antigens exist, that they are caused by somatic mutations, and that these antigens can induce both humoral and cell-mediated immune responses. Because tumor-specific antigens are exclusively expressed by the cancer cell and are often crucial for tumorigenicity, they are ideal targets for anti-cancer immunotherapy. Nevertheless, the antigens that are targeted today by anti-tumor immunotherapy are not tumor-specific antigens, but antigens that are normal molecules also expressed by normal tissues (so-called "tumor-associated" antigens). If tumor-specific antigens exist and are ideal targets for immunotherapy, why are they not being targeted? In this review, we summarize current knowledge of tumor-specific antigens: their identification, immunological relevance and clinical use. We discuss novel tumor-specific epitopes and propose new approaches that could improve the success of cancer immunotherapy, especially for the treatment of solid tumors.