Melanocortin 1 Receptor-derived peptides are efficiently recognized by cytotoxic T lymphocytes from melanoma patients

Background

Melanocortin 1 Receptor (MC1R) is expressed in a majority of melanoma biopsies and cell lines. We previously demonstrated that three hydrophobic low-affinity HLA-A2-restricted MC1R-derived peptides: MC1R_291–298, MC1R_244–252 and MC1R_283–291 can elicit cytotoxic T-lymphocytes (CTL) responses from normal donor peripheral blood lymphocytes (PBL). Moreover, peptide-specific CTL recognized a panel of MHC-matched melanomas, demonstrating that human melanoma cell lines naturally present MC1R epitopes. However, the natural presence of MC1R-specific T cells in melanoma patient's tumour and blood remains unknown.

Methods

The presence of anti-MC1R specific CD8⁺ T cells was established in a population of melanoma-specific T cells derived from peripheral blood mononuclear cells (PBMC) and tumour-infiltrating lymphocytes (TIL) from HLA-A2⁺ melanoma patients.

Results

CTLs specific for the three MC1R-derived peptides that lysed allogeneic HLA-A2⁺MC1R⁺ melanomas were elicited from PBMC, demonstrating the existence of an anti-MC1R T cell repertoire in melanoma patients. Moreover, TILs also recognized MC1R epitopes and HLA-A2⁺ melanoma cell lines. Finally, HLA-A2/MC1R₂₄₄-specific CD8⁺ T cell clones derived from TILs and a subset of MC1R₂₉₁ specific TILs were identified using HLA-A2/MC1R tetramers.

Conclusion

Our results demonstrate that MC1R-derived peptides are common immunogenic epitopes for melanoma-specific CTLs and TILs, and may thus be useful for the development of anti-melanoma immunotherapy.     

PD-1/PD-L1免疫检查点抑制剂在多形性胶质母细胞瘤中的研究进展

多形性胶质母细胞瘤(Glioblastoma multiforme, GBM)是目前最常见的原发性恶性脑肿瘤之一。GBM具有高侵袭性、高复发率和低生存率等特点,预后较差。程序性细胞死亡受体1(Programmed cell death receptor 1,PD-1)/程序性细胞死亡配体1(Programmed cell death ligand 1,PD-L1)作为主要的免疫检查点(Immune checkpoint, IC),形成免疫通路,可触发免疫反应的负性调控,增强脑组织中GBM细胞的侵袭性。在GBM的治疗研究中,免疫检查点抑制剂(Immune checkpoint inhibitor, ICI)也受到了相当大的关注。ICI通过抑制负性免疫调节途径来激活抗肿瘤反应,为GBM提供了新的治疗途径。目前已有多项临床研究集中在标准治疗(替莫唑胺、放疗)、靶向治疗和其他免疫治疗的联合应用方面。本综述阐述了PD-1/PD-L1通路,概述了PD-1/PD-L1 ICI单药、新辅助治疗以及联合化疗、放疗、靶向治疗、激素等多种方式治疗GBM的研究进展。     

肠道菌群与肿瘤免疫治疗疗效及不良反应关系的研究进展

肠道菌群是寄生于肠道内微生物的总称。肠道菌群受到宿主饮食和药物等多种因素影响,同时,肠道菌群也可以参与调控宿主免疫状态。目前,已有一些研究证实了肠道菌群与抗肿瘤免疫治疗疗效及不良反应具有相关性,且调节肠道菌群可以提升免疫治疗疗效,但是具体的机制尚不清楚。本文对肠道菌群与肿瘤免疫治疗现有的研究进展及不足进行了系统综述。     

肾癌患者治疗方法的选择

目的:探讨肾细胞癌的不同手术方式、术前肾动脉栓塞及免疫治疗的临床应用价值。方法:回顾性分析179例肾细胞癌患者的临床资料。对患者的临床资料分组进行对比,并对治疗效果和随访结果作进一步统计学分析。结果:小肾癌行肾癌根治术与保留肾组织手术效果比较,在手术时间、术后住院时间、术后5年生存率上差异均无统计学意义(P>0.05);78例术前行选择性肾动脉栓塞者,手术证实栓塞效果满意。结论:保肾单位手术是治疗局限性小肾癌的有效手段;较大的肾癌术前进行肾动脉栓塞术便于手术切除病灶,提高了肿瘤的切除率;免疫治疗是继手术治疗之后的又一种主要临床治疗方式,尤其肿瘤疫苗的出现,对于晚期肾癌及转移癌效果明显。     

慢性HBV感染的免疫治疗

目前现有的抗病毒药物对慢性HBV感染的疗效不甚满意.HBV感染的控制和清除有赖于机体的免疫系统,其感染慢性化与机体特异性免疫,尤其是细胞免疫功能低下密切相关.旨在通过增强或恢复机体抗HBV免疫功能以控制和清除HBV感染的免疫治疗是被人们寄予厚望的一种治疗策略,备受关注.本文将从树突状细胞、调节性T细胞、CD8~ T细胞、治疗性疫苗等几个方面对近几年慢性HBV感染的免疫学和免疫治疗研究进展进行综述.     

术前调强放疗联合新辅助治疗可切除局部晚期食管鳞状细胞癌的疗效分析

目的 探讨调强放疗（IMRT）联合特瑞普利单抗和铂类方案治疗可切除局部晚期食管鳞状细胞癌（ESCC）的疗效与安全性。方法 收集2019年12月—2022年11月在厦门大学附属中山医院接受新辅助治疗的局部晚期ESCC患者120例,根据治疗方法的不同将120例ESCC患者分为对照组（n=60）和观察组（n=60）。对照组接受特瑞普利单抗联合紫衫醇和卡铂治疗,观察组在此基础上应用IMRT治疗。治疗后评价是否可进行手术,比较两组的R0切除率、病理完全缓解（pCR）率、主要病理反应（MPR）率、客观缓解率（ORR）及疾病控制率（DCR）。观察两组围术期相关指标,术后随访24个月比较两组远期疗效及安全性。结果 两组患者的新辅助治疗完成率均达100%,观察组的R0切除率为91.67%,pCR率为40.00%,MPR率为61.67%,ORR为86.67%,DCR为96.67%,均显著高于对照组（P＜0.05）。两组在手术时间、术中出血量及术后并发症方面比较差异无统计学意义（P＞0.05）。随访24个月后,两组的无进展生存率和总生存率比较差异无统计学意义（P＞0.05）。两组患者发生贫血、恶心、呕吐、白细胞减少等不良反应情况比较差异无统计学意义（P＞0.05）。结论 IMRT联合特瑞普利单抗加紫杉醇加卡铂的新辅助治疗模式可提高局部晚期可切除ESCC的临床疗效,且安全性良好     

Immunotherapy: A new standard in the treatment of metastatic clear cell renal cell carcinoma

Renal cell cancer (RCC) represents 2%-3% of all adulthood cancers and is the most common malignant neoplasm of the kidney (90%). In the mid-nineties of the last century, the standard of treatment for patients with metastatic RCC was cytokines. Sunititib and pazopanib were registered in 2007 and 2009, respectively, and have since been the standard first-line treatment for metastatic clear cell RCC (mccRCC). Renal cell cancer is a highly immunogenic tumor with tumor infiltrating cells, including CD8+ T lymphocytes, dendritic cells, natural killer cells (NK) and macrophages. This observation led to the design of new clinical trials in which patients were treated with immunotherapy. With the growing evidence that proangiogenic factors can have immunomodulatory effects on the host’s immune system, the idea of combining angiogenic drugs with immunotherapy has emerged, and new clinical trials have been designed. In the last few years, several therapeutic options have been approved [immunotherapy and immunotherapy/tyrosine kinase inhibitors (TKI)] for the first-line treatment of mccRCC. Nivolumab/ipilimumab is approved for the treatment of patients with intermediate and poor prognoses. Several checkpoint inhibitors (pembrolizumab, nivolumab, avelumab) in combination with TKI (axitinib, lenvatinib, cabozantinib) are approved for the treatment of patients regardless of their International mRCC Database Consortium prognostic group and PD-L1 expression. There is no specific and ideal biomarker that could help in selecting the ideal patient for the appropriate first-line treatment.     

Immune evasion mechanisms and therapeutic strategies in gastric cancer

Gastric cancer (GC) is a malignancy with a high incidence and mortality. The tumor immune microenvironment plays an important role in promoting cancer development and supports GC progression. Accumulating evidence shows that GC cells can exert versatile mechanisms to remodel the tumor immune microenvironment and induce immune evasion. In this review, we systematically summarize the intricate crosstalk between GC cells and immune cells, including tumor-associated macrophages, neutrophils, myeloid-derived suppressor cells, natural killer cells, effector T cells, regulatory T cells, and B cells. We focus on how GC cells alter these immune cells to create an immunosuppressive microenvironment that protects GC cells from immune attack. We conclude by compiling the latest progression of immune checkpoint inhibitor-based immunotherapies, both alone and in combination with conventional therapies. Anti-cytotoxic T-lymphocyte-associated protein 4 and anti-programmed cell death protein 1/programmed death-ligand 1 therapy alone does not provide substantial clinical benefit for GC treatment. However, the combination of immune checkpoint inhibitors with chemotherapy or targeted therapy has promising survival advantages in refractory and advanced GC patients. This review provides a comprehensive understanding of the immune evasion mechanisms of GC, and highlights promising immunotherapeutic strategies.     

Advancement of chimeric antigen receptor-natural killer cells targeting hepatocellular carcinoma

With the advance of genome engineering technology, chimeric antigen receptors (CARs)-based immunotherapy has become an emerging therapeutic strategy for tumors. Although initially designed for T cells in tumor immunotherapy, CARs have been exploited to modify the function of natural killer (NK) cells against a variety of tumors, including hepatocellular carcinoma (HCC). CAR-NK cells have the potential to sufficiently kill tumor antigen-expressing HCC cells, independent of major histocompatibility complex matching or prior priming. In this review, we summarize the recent advances in genetic engineering of CAR-NK cells against HCC and discuss the current challenges and prospects of CAR-NK cells as a revolutionary cellular immunotherapy against HCC.     

微卫星不稳定型子宫内膜癌的临床特点和治疗

子宫内膜癌（endometrial cancer,EC）近年发病率呈上升趋势,传统的病理组织分型不能精准地指导患者的个体化治疗及评估预后,基于分子生物学技术提出的EC分子分型应运而生,这种分子分型在EC患者术后放化疗、免疫治疗及靶向治疗中均具有重要的指导作用。其中,微卫星不稳定（microsatellite instability,MSI）型EC为癌症基因组图谱（The Cancer Genome Atlas,TCGA）分子分型中的一种,MSI型EC具有独特的临床特征和病理学特征,并且在治疗及预后方面也与其他分型的EC较为不同。分子分型现已整合到欧洲妇科肿瘤学会指南中,研究表明,MSI型EC患者化疗获益不高,但受益于免疫治疗,现已推荐使用免疫治疗联合抗血管生成药物治疗。目前关于MSI型EC患者的病理特点、预后和治疗方面仍存在一些争议,对MSI型EC患者的几项药物联合治疗仍在研究中,在EC患者中根据分子分型进行个体化治疗已成为研究的重点。