CAR-T细胞治疗实体瘤的挑战与应对策略

嵌合抗原受体T细胞（CAR-T）作为肿瘤免疫治疗的新疗法,已在多种血液肿瘤的临床治疗中取得了突破性进展,但用于实体瘤的治疗仍面临着诸多挑战。本文根据CAR-T细胞在实体瘤中的应用情况,总结其疗效不佳的原因,包括缺乏肿瘤特异性靶抗原、T细胞的转运及肿瘤浸润障碍、肿瘤微环境的免疫抑制等;并以此分析可行的解决策略,如提高肿瘤细胞特异性、提高对实体瘤的转运及浸润、解除免疫抑制以及提高CAR-T细胞在体内的持久性等,以期为后续CAR-T细胞治疗实体肿瘤研究提供思路。     

嵌合抗原受体T细胞免疫疗法治疗多发性骨髓瘤的研究进展

免疫疗法在恶性肿瘤治疗中的应用正日益受到关注.嵌合抗原受体(CAR)技术是一种新兴的免疫疗法,在血液肿瘤的治疗上具有巨大的潜力.嵌合抗原受体T细胞免疫疗法(CAR-T)可通过特异性识别靶抗原来杀伤骨髓瘤细胞,使治疗复发难治性多发性骨髓瘤成为可能.该文重点对CAR-T在多发性骨髓瘤治疗方面的研究进展作一综述,并对可能作为CAR-T治疗多发性骨髓瘤的靶抗原进行了分析.     

CAR-T细胞治疗产品非临床药效学研究关注点

CAR-T细胞（Chimeric Antigen Receptor T Cells,CAR-T）是一种表达嵌合抗原受体的基因工程T细胞,也称"活的药物",可以增强基因工程T细胞的特异性,能够以MHC （主要组织相容性复合体,Major Histocompatibility Complex,MHC）非依赖性的方式高度靶向肿瘤抗原,是治疗肿瘤的一种新手段。最近,临床上使用CAR-T细胞治疗复发、难治性血液恶性肿瘤和多发性骨髓瘤取得了很好的疗效;同时,采用CAR-T细胞治疗实体瘤的研发也在积极开展。根据所构建的CAR-T细胞不同的适应证和作用原理,构建不同的动物肿瘤模型,研究CAR-T细胞在动物模型的抗肿瘤活性,可以对CAR-T细胞进行概念验证性研究并证明其体内药效学活性,为临床研究提供有力的数据支持。     

嵌合抗原受体T细胞的代谢优化★

基因工程设计的嵌合抗原受体（CAR）T细胞对血液肿瘤的治疗取得了显著成效，但对实体肿瘤的疗效有限。肿瘤异质性、肿瘤微环境的代谢挑战和免疫抑制导致了CAR-T细胞的功能障碍，造成了CAR-T细胞疗法对实体肿瘤的治疗困境。本文综述了CAR-T细胞结构、CAR-T细胞制备和涉及的信号通路，简述了乳酸、谷氨酰胺和葡萄糖等代谢物对CAR-T细胞的影响。此外，本文还从CAR-T细胞设计、体内外扩增条件和克服CAR-T细胞治疗的毒性效应三个角度概括CAR-T细胞治疗的最新进展。通过对CAR-T细胞的代谢优化，打破传统CAR-T细胞治疗的局限性，突破其现有的肿瘤类型限制。     

肿瘤干细胞的来源、标志物以及在毒理学研究中的应用

肿瘤干细胞(CSCs)是一类具有自我更新能力并且可以产生异质性肿瘤的细胞,是目前肿瘤研究的热点,在肿瘤的发生、发展和转移的机制探讨,肿瘤的评估、早期诊断和预后以及抗肿瘤药物的筛选方面展现了良好的应用前景。本文综述了CSCs来源的几种形式,归纳了常见恶性肿瘤中的标志物,概括了CSCs在毒理学研究中的应用,最后展望了CSCs研究的发展方向。     

CAR-T cells: Early successes in blood cancer and challenges in solid tumors

New approaches to cancer immunotherapy have been developed, showing the ability to harness the immune system to treat and eliminate cancer. For many solid tumors, therapy with checkpoint inhibitors has shown promise. For hematologic malignancies, adoptive and engineered cell therapies are being widely developed, using cells such as T lymphocytes, as well as natural killer (NK) cells, dendritic cells, and potentially others. Among these adoptive cell therapies, the most active and advanced therapy involves chimeric antigen receptor (CAR)-T cells, which are T cells in which a chimeric antigen receptor is used to redirect specificity and allow T cell recognition, activation and killing of cancers, such as leukemia and lymphoma. Two autologous CAR-T products have been approved by several health authorities, starting with the U.S. Food and Drug Administration (FDA) in 2017. These products have shown powerful, inducing, long-lasting effects against B cell cancers in many cases. In distinction to the results seen in hematologic malignancies, the field of using CAR-T products against solid tumors is in its infancy. Targeting solid tumors and trafficking CAR-T cells into an immunosuppressive microenvironment are both significant challenges. The goal of this review is to summarize some of the most recent aspects of CAR-T cell design and manufacturing that have led to successes in hematological malignancies, allowing the reader to appreciate the barriers that must be overcome to extend CAR-T therapies to solid tumors successfully.KEY WORDS: Immunotherapy, T cell therapy, Chimeric antigen receptor (CAR), Genetic engineering     

Induced Pluripotent Stem Cells (iPSCs) Provide a Potentially Unlimited T Cell Source for CAR-T Cell Development and Off-the-Shelf Products

Pharmaceutical Research - Chimeric antigen receptor T (CAR-T) cell therapy has been increasingly conducted for cancer patients in clinical settings. Progress in this therapeutic approach is...     

Rapid phenotyping of cancer stem cells using multichannel nanosensor arrays

Cancer stem cells (CSCs) contribute to multidrug resistance, tumor recurrence and metastasis, making them prime therapeutic targets. Their ability to differentiate and lose stem cell properties makes them challenging to study. Currently, there is no simple assay that can quickly capture and trace the dynamic phenotypic changes on the CSC surface. Here, we report rapid discrimination of breast CSCs from non-CSCs using a nanoparticle-fluorescent-protein based sensor. This nanosensor was employed to discriminate CSCs from non-CSCs, as well as CSCs that had differentiated in vitro in two breast cancer models. Importantly, the sensor platform could also discriminate CSCs from the bulk population of cells in patient-derived xenografts of human breast cancer. Taken together, the results obtained demonstrate the feasibility of using the nanosensor to phenotype CSCs and monitor their fate. Furthermore, this approach provides a novel area for therapeutic interventions against these challenging targets.     

Chimeric antigen receptor T cell therapy and nephrotoxicity: From diagnosis to treatment strategies

Chimeric antigen receptor T (CAR-T) cell therapy is a breakthrough in cancer treatment. With the widespread use of this therapy, increasing evidence is available that CAR-T cell therapy is associated with acute kidney injury (AKI). Nephrologists need to understand the potential nephrotoxicity arising from CAR-T cell therapy. Determining the cause of AKI is a key factor of clinical management. This review focuses on the clinical use of CAR-T cell therapy and the cause and outcomes of nephrotoxicity with its use. We also provide clinical suggestions for clinicians towards both better diagnosis and management of AKI in those receiving CAR-T cell therapy.     

肿瘤治疗的新途径：嵌合抗原受体T细胞疗法

免疫疗法已经成为癌症治疗中的重要手段。使用嵌合抗原受体（chimeric antigen receptor,CAR）修饰的T细胞治疗癌症因其显著的疗效成为了癌症治疗研究的新方向。CAR包含抗原结合部分、铰链区、跨膜结构域以及结合活化T细胞的细胞共刺激结构。对目标肿瘤的特异性清除是通过CAR-T细胞对抗原的特异性选择和共刺激信号转导,CAR-T细胞在过继后的转运、维持,以及抗肿瘤功能的保留实现的。此文对目前基于CAR-T细胞疗法的基本原理及临床应用作一阐述。     

Inhibition of CXCL12/CXCR4 autocrine/paracrine loop reduces viability of human glioblastoma stem-like cells affecting self-renewal activity

Cancer stem cells (CSCs) or tumor initiating cells (TICs) drive glioblastoma (GBM) development, invasiveness and drug resistance. Distinct molecular pathways might regulate CSC biology as compared to cells in the bulk tumor mass, representing potential therapeutic targets. Chemokine CXCL12 and its receptor CXCR4 control proliferation, invasion and angiogenesis in GBM cell lines and primary cultures, but little is known about their activity in GBM CSCs. We demonstrate that CSCs, isolated from five human GBMs, express CXCR4 and release CXCL12 in vitro, although different levels of expression and secretion were observed in individual cultures, as expected for the heterogeneity of GBMs.CXCL12 treatment induced Akt-mediated significant pro-survival and self-renewal activities, while proliferation was induced at low extent. The role of CXCR4 signaling in CSC survival and self-renewal was further demonstrated using the CXCR4 antagonist AMD3100 that reduced self-renewal and survival with greater efficacy in the cultures that released higher CXCL12 amounts. The specificity of CXCL12 in sustaining CSC survival was demonstrated by the lack of AMD3100-dependent inhibition of viability in differentiated cells derived from the same GBMs.These findings, although performed on a limited number of tumor samples, suggest that the CXCL12/CXCR4 interaction mediates survival and self-renewal in GBM CSCs with high selectivity, thus emerging as a candidate system responsible for maintenance of cancer progenitors, and providing survival benefits to the tumor.     

肿瘤干细胞的生物学特性及临床意义的研究进展

研究表明肿瘤干细胞（cancer stem cells,CSC）起源于正常干细胞（stem cells,SC）的基因突变,SC的DNA受到损伤或处于与肿瘤相关的微环境是其发生基因突变,进而转化为CSC的主要原因。CSC可与肿瘤细胞相互转化,且与肿瘤细胞相比,其增殖和转移的速度更快,恶性程度更高,对化疗和放疗的耐受性更强。不同肿瘤的CSC生物学标记并不完全相同,即使是同一类肿瘤,因细胞系不同,生物学标记也有差异。CSC的生物学标记物也可以用于CSC的诊断、肿瘤的预后判断和治疗。因此,探索CSC的生物学标记和调控因子,并将其作为肿瘤的治疗靶标,开发相关的药物,将是未来CSC和肿瘤研究的重点。本文主要对肿瘤干细胞的起源、生物学特性及其临床意义进行了综述。     

H⁺-myo-inositol transporter SLC2A13 as a potential marker for cancer stem cells in an oral squamous cell carcinoma

Cancer Stem Cells (CSCs) from tumors of different phenotypes possess a marked capacity for proliferation, self-renewal, and differentiation. They also play a critical role in cancer recurrence. Although CSC has been regarded as a new target for cancer therapy, the fundamental questions in the CSC study have not been resolved mainly due to the lack of proper CSC markers. To find new CSC markers for oral squamous cell carcinoma (OSCC), we cultured the primary tumor cells from OSCC patients the regular culture condition and the sphere-forming culture condition to enrich primary tumor cells and potential CSCs. We compared gene expression profiles between sphere-forming and non-forming cells, thus identifying that 23 membrane protein-coding genes were over-expressed in the sphere-forming cells. Among them, 8 belonged to the solute carrier (SLC) protein family. H?-myo-inositol transporter SLC2A13 and monocarbohydrate transporter SLC16A6 genes that were consistently increased in the sphere-forming cells in the primary cultures of OSCC samples. Confocal microscopy revealed that SLC2A13-expressing cells were embedded in the limited areas of tumor tissue as a cluster, while SLC16A6 was uniformly detected in hyperplastic epithelium. Moreover, SLC2A13 an expression was induced in human breast adenocarcinoma MCF7 cells after serum starvation. Taken together, our results suggest that SLC2A13 can be a potential markers for CSC in various tumors.     

IL-7及IL-15在肿瘤免疫疗法中的应用

嵌合抗原受体T细胞(CAR-T)免疫疗法经过体外将正常T细胞进行基因修饰后,再回输入患者体内,以非人类白细胞抗原(HLA)依赖性方式识别肿瘤细胞并进行杀伤。自2017年美国食品药品监督管理局(FDA)批准了诺华及Kite公司两款嵌合抗原受体T细胞产品上市以来,嵌合抗原受体T细胞疗法在全球展开蓬勃发展。白细胞介素-2(IL-2)、白细胞介素-4(IL-4)、白细胞介素-7(IL-7)、白细胞介素-15(IL-15)、白细胞介素-21(IL-21)等细胞因子可促使嵌合抗原受体T细胞在体外有效增殖。本文主要对白细胞介素-7及白细胞介素-15进行阐述,探讨其作用机理以及临床应用。     

Understanding and targeting cancer stem cells: therapeutic implications and challenges

Cancer stem cells (CSCs) have been identified as rare cell populations in many cancers, including leukemia and solid tumors. Accumulating evidence has suggested that CSCs are capable of self-renewal and differentiation into various types of cancer cells. Aberrant regulation of gene expression and some signaling pathways has been observed in CSCs compared to other tumor cells. CSCs are thought to be responsible for cancer initiation, progression, metastasis, recurrence and drug resistance. The CSC hypothesis has recently attracted much attention due to the potential for discovery and development of CSC-related therapies and the identification of key molecules involved in controlling the unique properties of CSC populations. Over the past several years, a tremendous amount of effort has been invested in the development of new drugs, such as nanomedicines, that can take advantage of the “Achilles'' heel” of CSCs by targeting cell-surface molecular markers or various signaling pathways. Novel compounds and therapeutic strategies that selectively target CSCs have been identified, some of which have been evaluated in preclinical and clinical studies. In this article, we review new findings related to the investigation of the CSC hypothesis, and discuss the crucial pathways involved in regulating the development of CSC populations and the advances in studies of drug resistance. In addition, we review new CSC-targeted therapeutic strategies aiming to eradicate malignancies.     

嵌合抗原受体修饰T细胞治疗前列腺癌的研究进展

摘要：嵌合抗原受体修饰T细胞（CAR-T）是近年来免疫治疗的热点,在血液系统疾病的治疗中取得了显著的临床疗效。目前,CAR-T在前列腺癌（PCa）治疗的研究中也取得了较大进展,其中以前列腺特异性膜抗原（PSMA）和前列腺干细胞抗原（PSCA）为靶点的CAR-T治疗进展较快,其可显著抑制肿瘤细胞生长,一定程度地延缓疾病进展。本文综述了前列腺肿瘤相关抗原（TAA）在前列腺癌CAR-T治疗中的最新研究进展,并对CAR-T在前列腺癌治疗中的挑战予以简要探讨,以期为临床提供参考。     

CAR-T细胞治疗产品非临床研究动物模型的发展和应用概述

嵌合抗原受体T细胞（CAR-T,Chimeric Antigen Receptor T Cell）已成为近年来癌症免疫疗法领域的研究热点,由于其具有特异性高、选择性强等优点,在肿瘤治疗领域中具有巨大的潜力。同时,CAR-T疗法可能带来特殊毒性风险,包括细胞因子释放综合征、神经毒性、B细胞减少和靶向与脱靶毒性等。尽量在研发早期、在人体使用前获得CAR-T产品的有效性和安全性等非临床信息至关重要,选择合适的动物模型进行上述相关研究可以大大提高对临床结果的预测性。目前,已用于CAR-T产品研究和正处于探索阶段的动物模型主要包括同源小鼠模型、转基因小鼠、移植瘤小鼠模型、免疫系统重建人源化小鼠以及灵长类动物模型。但是,由于CAR-T细胞产品的个性化程度高,人和动物免疫系统特性存在差异,人源细胞在动物体内易受到免疫排斥等原因,人源产品在动物模型上的研究结果尚不能完全反映其在人体内的作用情况。因此,需要根据产品特点和研究目的,构建或者选择适当的动物模型,为CAR-T细胞治疗产品非临床研究提供有效的研究工具。     

Metastatic cancer stem cells: new molecular targets for cancer therapy

The cancer stem cell (CSC) hypothesis, predicts that a small subpopulation of cancer cells that possess "stem-like" characteristics, are responsible for initiating and maintaining cancer growth. According to the CSC model the many cell populations found in a tumour might represent diverse stages of differentiation. From the cellular point of view metastasis is considered a highly inefficient process and only a subset of tumour cells is capable of successfully traversing the entire metastatic cascade and eventually re-initiates tumour growth at distant sites. Some similar features of both normal and malignant stem cells suggest that CSCs are not only responsible for tumorigenesis, but also for metastases. The CSC theory proposes that the ability of a tumour to metastasize is an inherent property of a subset of CSCs. The similar biological characteristics shared by normal stem cells (NSCs) and CSCs mainly implicate self-renewal and differentiation potential, survival ability, niche-specific microenvironment requirements and specific homing to metastatic sites and may have important implications in terms of new approaches to cancer therapy in the metastatic setting. There are several agents targeting many of these CSC features that have shown to be effective both in vitro and in vivo. Although clinical trials results are still preliminary and continue under investigation, these new therapies are very promising. The identification of new therapeutic targets and drugs based on CSC model constitutes a great challenge.     

Effective tumor immunity to melanoma mediated by B16F10 cancer stem cell vaccine

Although tumor vaccines have been considered a promising immunotherapy approach, therapeutic tumor vaccines are mostly disappointing in the clinic due to vaccine weak immunogenicity. Cancer stem cells (CSCs) may broaden the antigenic breadth and effectively induce the immune responses against autologous cancer cells. Here we report on the development of the B16F10 CD133⁺ CD44⁺ CSCs (B16F10 CSCs) vaccine to induce tumor immunity to melanoma in mice. Efficacy of against melanoma was evaluated by analysis of tumor growth and mouse survival. Immunogenicity was assessed by ELISA and flow cytometric assays, including serum cytokines, cytotoxic activity of NK cells and splenocytes in the immunized mice. The results showed that the B16F10 CSC vaccine resulted in tumor shrinkage and mouse lifespan extension. The cytotoxic activity and IFN-γ level were significantly increased in mice immunized with B16F10 CSC vaccine compared with the mice immunized with control vaccines. Additionally, New York esophageal squamous cell carcinoma-1, an efficient tumor associated antigen over-expressed by B16F10 CSCs, was markedly reduced in expression in melanoma tissue, suggesting decrease of CSC subpopulation due to B16F10 CSC vaccination. Collectively, the findings may represent a new powerful approach for treatment of melanoma by B16F10 CSC vaccination.