二代测序在胰腺癌中的研究进展

胰腺癌是高度恶性的消化系统肿瘤.由于极差的预后及有限的治疗方法,对胰腺癌分子生物学更进一步的了解及研究,可能会明显提高诊断的精确性及治疗的有效性.二代测序(next-generation sequencing,NGS)是对传统测序一次革命性的改变,具有高通量、高敏感性、高自动化程度等优点.利用二代测序技术,筛选胰腺癌致病基因,研究胰腺癌的发病机制,进而指导胰腺癌的诊断及治疗,有望改进胰腺癌的诊疗现状.近年来,二代测序在胰腺癌的应用中取得巨大进展,该文就二代测序及其在胰腺癌中的研究进展作一综述.     

晚期恶性肿瘤基因突变状态二代测序临床意义分析

目的 靶向治疗是晚期恶性肿瘤的重要治疗方法,二代测序能够准确、高通量地检测基因突变情况,对恶性肿瘤治疗有重要意义.本研究运用二代基因测序(next-generation sequencing,NGS)技术检测晚期恶性肿瘤的基因突变情况,并初步分析错义突变的临床意义.方法 2011-09-01-2016-09-30收集陕西省人民医院肿瘤内科93例晚期恶性肿瘤患者病理组织石蜡标本,利用离子个体化基因检测仪(Ion Personal Genome Machine,Ion Torrent PGM)平台检测标本16个肿瘤相关基因428个常见的突变位点的突变状态,并查询临床试验(Clinical Trails)与美国食品与药物管理局(Food and Drug Administration,FDA)官网数据资料.结果 共发现119个错义突变,其中TP53发生频率最高为34.5％(41/119);除TP53突变在各瘤种中均占较大比例外,肺癌突变频率最高为表皮生长因子受体(epidermal growth factor receptor,EGFR) 25.7％(9/35),结直肠癌为KRAS 31.6％ (6/19),胃癌为KDR 3/6,卵巢癌为KRAS 2/7,宫颈癌为KDR 3/5.70例(75.3％,70/93)检测发现＞1个的错义突变位点;93.8％(15/16)的被检测基因有正在研发中的小分子抑制剂和(或)单抗类制剂,75.0％(12/16)的被检测基因已有FDA批准用于特定瘤种的靶向药物,68.8％(11/16)的被检测基因有尚未被FDA批准的靶向药物.结论 晚期恶性肿瘤基因错义突变发生率较高,且不同瘤种的突变谱不同,目前基于NGS指导的恶性肿瘤个体化靶向治疗有广阔的应用前景.     

晚期胰腺癌的内科治疗现状

近年来胰腺癌发病率越来越高,且预后较差,治疗颇为棘手.多数晚期胰腺癌患者的治疗以内科化疗为主,同时根据病情予放射治疗、同步放化疗、靶向治疗、免疫治疗及介入治疗等.传统化疗以吉西他滨、氟尿嘧啶、铂类为主,但疗效欠佳,纳米微粒型白蛋白结合型紫杉醇、激酶抑制剂(如厄洛替尼)、单克隆抗体(如尼妥珠单抗)等药物目前无显著阳性结果,免疫治疗方面相关临床研究结果不足,故寻求有效安全的内科治疗是目前晚期胰腺癌研究的主要攻点.本文就晚期胰腺癌的内科治疗现状作一综述.     

肿瘤大基因包高通量测序在临床中的应用进展

随着高通量测序技术的推进、大数据处理分析水平的提升, 以及基于各种分子标记物的靶向治疗和免疫治疗抗肿瘤活性的表现, 以高通量测序和大数据为基础的诊疗逐渐应用于临床, 不同基因数的基因包(panel)检测为肿瘤诊疗提供依据。本文就高通量测序panel的分类, 大panel在肿瘤诊断、靶向治疗、免疫治疗中的应用以及大panel在临床应用中所遇到的问题进行综述, 旨在为其在临床上的应用提供参考, 促进精准医疗推广应用。      

胰腺癌精准治疗：从小众走向主流

胰腺癌恶性程度高,预后差,治疗手段有限,精准治疗是提高胰腺癌患者疗效的大势所趋。超过1/4的胰腺癌患者存在可治疗的靶点,主要包括KRAS突变、同源重组修复缺陷、融合基因改变、免疫微环境等四大类分子靶标,其中有恶性肿瘤家族史或个人史、年轻患者及腺泡细胞癌等胰腺癌患者更可能从精准治疗中获益。然而目前胰腺癌患者最终接受精准治疗的不足4%,肿瘤分子谱检测每有KRAS突变状态、肿瘤细胞含量、融合基因、胚系突变等关键信息缺失,精准治疗仍是一种小众治疗手段。因而有必要建立精准检测技术规范,打造专业化的精准分析团队,强调多中心协作从而积累循证医学证据,推动胰腺癌精准治疗从小众走向主流,造福于广大胰腺癌患者。最新的研究结果表明,胰腺癌精准治疗可改善患者预后,延长生存期。2019年,《新英格兰医学杂志》（New England Journal of Medicine）报道了针对具有BRCA1或BRCA2胚系突变的晚期胰腺癌进行多聚二磷酸腺苷核糖聚合酶[poly (ADP-ribose) polymerase,PARP]抑制剂奥拉帕利维持治疗的POLO研究,从而拉开了胰腺癌精准治疗的序幕。2020年,得克萨斯大学MD安德森癌症中心（The University of Texas MD Anderson Cancer Center）Pishvaian等报道了“知道您的肿瘤（Know Your Tumor,KYT）”计划。结果表明,在1 856例胰腺癌患者中,具有可治疗靶点且匹配对应治疗的患者（46例,中位生存期为2.58年）其预后明显优于具有可治疗靶点但未匹配对应治疗的患者[143例,中位生存期为1.51年,风险比（hazard ratio,HR） = 0.42,P = 0.004]以及无可治疗靶点的患者（488例,中位生存期为1.32年,HR = 0.34,P<0.000 1）。然而,具有可治疗靶点但未匹配对应治疗的患者的预后却与无可治疗靶点的患者差异无统计学意义（P = 0.10）。这项真实世界研究表明,对有可治疗靶点的胰腺癌实施精准治疗可将胰腺癌患者的生存期延长1年以上。目前胰腺癌精准治疗的靶标包括KRAS突变状态（KRAS野生型,KRAS G12C突变）、同源重组修复缺陷（BRCA1/2、PALB2、ATM/ATR/ATRX、CHEK2、CDK12、RAD51、NBN、BLM、FANC、RAD51/51C、RAD50、BAP1、BARD1、BRIP1和MRE11）、融合基因改变（NTRK、NRG1、ALK、RAF、RET、MET、FGFR2/3和ROS）、免疫微环境[MSI-H、TMB和MMR-D（MLH1、MLH3、MSH2、MSH3、MSH6、PMS1、PMS2、POLE和EPCAM）]、其他[BRAF、 人表皮生长因子受体2（human epidermal growth factor receptor 2,HER2）]等。由于胰腺癌精准治疗靶点相对有限且分布不集中,患者存在生存期短以及标本难获得等劣势,因而有必要建立专业化的精准分析团队,进而推动胰腺癌精准治疗的发展。相信随着业内对精准治疗的重视,胰腺癌的精准治疗必将迎来春天。     

胰腺癌免疫治疗研究进展

胰腺癌作为一种致命的恶性肿瘤,起病隐匿,对放化疗、靶向治疗等传统治疗不敏感,患者预后极差。免疫治疗是当今多种恶性肿瘤综合治疗的有效手段,以其显著临床疗效而备受瞩目。然而胰腺癌因其较低的肿瘤免疫原性和独特的肿瘤微环境在免疫治疗迅速发展的当今成为难以攻破的一方“免疫荒漠”。目前胰腺癌免疫治疗的研究方向主要包括：肿瘤疫苗、免疫检查点抑制剂、单克隆抗体、溶瘤病毒、T细胞治疗等。本文将对以上相关研究进展作一综述,以期为胰腺癌的免疫治疗提供新思路。     

肿瘤相关中性粒细胞与胰腺癌关系的研究进展

胰腺癌是一种起病隐匿、预后不良的消化系统恶性肿瘤,具有早期诊断困难、进展期生存时间短等特点。胰腺癌的肿瘤微环境(Tumor microenvironment, TME)中常常伴有大量免疫细胞的浸润,而肿瘤相关中性粒细胞(Tumor-associated neutrophils, TANs)作为TME的重要组成部分,在肿瘤的进程中起着重要作用。相关研究表明,TANs在胰腺癌的TME中发挥多种作用。本文从TANs与胰腺癌的关系进行综述,为理解胰腺癌发生机制与提出新疗法提供思路。     

胰腺癌术后辅助药物治疗的研究进展

胰腺癌是一种致死性极高的恶性肿瘤,其5年生存率不到8%。可行根治性手术的胰腺癌患者较未行手术者预后有显著差异,单纯的手术治疗仅能将胰腺癌5年生存率提高至10%左右,究其原因主要是单纯手术后复发、转移的几率仍然极高,且复发、转移后患者生活质量欠佳,预后极差,远期生存时间短。因此,寻求胰腺癌术后更加有效的辅助治疗药物或者方案,并进行规范、合理、综合的药物治疗,控制微转移,对防止和延迟复发意义重大,该研究领域也是近年来针对胰腺癌研究的重点方向。本文基于近年来胰腺癌术后治疗的研究进展做一综述。探索胰腺癌术后不同药物、不同治疗方案下的生存获益情况及胰腺癌术后治疗的药物发展趋势,为胰腺癌术后治疗提供有价值的参考。     

胰腺癌分子靶向治疗进展

胰腺癌在胃肠道肿瘤中预后差,5年生存率不到5％,发病率呈逐渐上升趋势。治疗主要是外科手术、化疗和放疗相结合的综合治疗,但目前常规治疗效果有限,因此针对胰腺癌生物学特性进行治疗是改善预后的关键。随着靶向治疗的进展,VEGF单克隆抗体和EGFR抑制剂在临床试验中都表现出较好的前景。其他靶向药物,如沙利度胺、基质金属蛋白酶抑制剂、COX-2抑制剂和法尼基转移酶抑制剂还在研究之中。分子靶向治疗将为胰腺癌的治疗提供新的机会。     

胰腺癌的分子靶向治疗

胰腺癌是恶性程度最高的肿瘤之一,它具有早期侵袭性生长和远处转移的特性,预后极差,据统计,只有15％病例可进行手术治疗,5年生存率不足3％,抗肿瘤治疗如放疗、化疗、免疫治疗不敏感是导致其预后恶劣的原因之一。肿瘤的发生、发展以及对抗肿瘤治疗效果欠佳,主要是因为肿瘤细胞对诱导凋亡的刺激缺乏反应。随着肿瘤靶向治疗的进展,与胰腺癌发生、发展、侵袭、转移有关的分子标志的逐步阐明,针对特异性分子靶向目标的治疗性药物相继产生,为改善胰腺癌治疗的效果提供了新的机会。     

胰腺癌:靶向治疗的前景

Pancreatic cancer is a devastating disease characterized by almost identical incidence and mortality rates. Since this tumour is mostly diagnosed in an advanced stage there is usually no option for a curative surgical resection. In addition, pancreatic cancers known to be resistant to conventional treatment modalities such as chemotherapy and radiotherapy. Therefore, novel strategies for targeting these tumors are urgently needed. The increasing knowledge on the underlying pathogenetic mechanisms has led to the identification of surface receptor molecules that initiate intracellular signalling cascades upon ligand binding, thus leading to tumor progression. Targeting these receptors or their secreted ligands is therefore an attractive new approach for cancer therapy. The epidermal growth factor receptor （EGFR） and the vascular endothelial growth factor receptor （VEGFR） are transmembrane tyrosine kinase receptors which can be targeted by various compounds such as antibodies or small molecule inhibitors. In addition, various molecules targeting proteins secreted by pancreatic cancers such as matrix metalloproteinases （MMP＇s） or intracellular oncogenic signalling components such as the farnesyltransferase have been proposed as potential new approaches for targeted cancer therapy. The use of these agents alone or in combination with conventional therapeutic regimens is currently being evaluated and shows first promising results for pancreatic cancer therapy.     

Real-World Evidence of Systemic Therapy Sequencing on Overall Survival for Patients with Metastatic BRAF-Mutated Cutaneous Melanoma

Aim: To evaluate optimal systemic therapy sequencing (first-line targeted therapy (1L-TT) vs. first-line immunotherapy (1L-IO)) in patients with BRAF-mutated metastatic melanoma. Methods: Nation-wide prospective data of patients with newly diagnosed BRAF-mutated metastatic melanoma were retrieved from the Canadian Melanoma Research Network. Results: Our study included 79 and 107 patients in the 1L-IO and 1L-TT groups, respectively. There were more patients with ECOG 0–1 (91% vs. 72%, p = 0.023) in the 1L-IO group compared to the 1L-TT group. Multivariable Cox analysis suggested no OS differences between the two groups (HR 0.838, 95%CI 0.502–1.400, p = 0.500). However, patients who received 1L-TT then 2L-IO had the longest OS compared to 1L-IO without 2L therapy, 1L-IO then 2L-TT, and 1L-TT without 2L therapy (38.3 vs. 32.2 vs. 16.9 vs. 6.3 months, p < 0.001). For patients who received 2L therapy, those who received 2L-IO had a trend towards OS improvement compared with the 2L-TT group (21.7 vs. 8.9 months, p = 0.053). Conclusions: Our nation-wide prospective study failed to establish any optimal systemic therapy sequencing in advanced BRAF-mutant melanoma patients. Nevertheless, we provided evidence that immunotherapy has durable efficacy in advanced BRAF-mutant melanoma patients, regardless of treatment line, and that Canadian medical oncologists were selecting the appropriate treatment sequences in a real-world setting, based on patients’ clinical and tumour characteristics.     

癌症免疫治疗和靶向治疗的相互作用

最近,对癌症发病机制的深入了解已经促进了新的治疗方法,如靶向药物治疗和癌症免疫治疗。靶向治疗旨在抑制维持肿瘤生长的至关重要的分子通路;而免疫治疗是刺激宿主的免疫反应,以达到长期的肿瘤抑制。靶向治疗也可以调节免疫系统,因此提出一种可能性,联合靶向治疗和免疫治疗可能有效地改善临床结果。     

The Clinically Actionable Molecular Profile of Early versus Late-Stage Non-Small Cell Lung Cancer,an Individual Age and Sex Propensity-Matched Pair Analysis

Background: Despite meticulous surgery for non-small cell lung cancer (NSCLC), relapse is as high as 70% at 5 years. Many institutions do not conduct reflexive molecular testing on early stage specimens, although targeted gene therapy may extend life by years in the event of recurrence. This ultimately delays definitive treatment with additional biopsy risking suboptimal tissue acquisition and quality for molecular testing. Objective: To compare molecular profiles of genetic alterations in early and late NSCLC to provide evidence that reflexive molecular testing provides clinically valuable information. Methods: A single-center propensity matched retrospective analysis was conducted using prospectively collected data. Adults with early and late-stage NSCLC had tissue subject to targeted panel-based NGS. Frequencies of putative drivers were compared, with 1:3 matching on the propensity score; p < 0.05 deemed statistically significant. Results: In total, 635 NSCLC patients underwent NGS (59 early, 576 late); 276 (43.5%) females; age 70.9 (±10.2) years; never smokers 140 (22.0%); 527 (83.0%) adenocarcinomas. Unadjusted frequencies of EGFR mutations were higher in the early cohort (30% vs. 18%). Following adjustment for sex and smoking status, similar frequencies for both early and late NSCLC were observed for variants in EGFR, KRAS, ALK, MET, and ROS1. Conclusion: The frequency of clinically actionable variants in early and late-stage NSCLC was found to be similar, providing evidence that molecular profiling should be performed on surgical specimens. This pre-determined profile is essential to avoid treatment delay for patients who will derive clinical benefit from targeted systemic therapy, in the high likelihood of subsequent relapse.     

基于二代测序技术探究胃癌中医证型的基因突变特征

摘 要：［目的］利用二代测序技术研究胃癌中医证型的基因突变特征,从肿瘤基因组层面初步探索胃癌中医证候的客观化指标,指导临床精准治疗。［方法］收集临床病理分期为Ⅰ~Ⅳ期且未经任何治疗的胃癌患者,根据2011年《胃癌中医诊疗方案》进行辨证分型,采用二代测序技术（含450个肿瘤相关突变基因）检测肿瘤细胞的基因突变情况,结合临床资料和中医证型进行生物信息学分析,从而探究胃癌中医证型的基因突变特点。［结果］共有130例Ⅰ～Ⅳ期胃癌患者纳入本研究,辨证分型为脾气虚证、血虚证、热毒证等共8个单证。对中医单证和测序获得的363个突变基因进行分析,得到与各单证相关的高频和驱动基因,脾气虚证多见ARID1A、PIK3CA、APC基因突变;血虚证多见KMT2C基因突变;热毒证多见TGFBR2、HNF1A、ERBB3、KMT2D基因突变。130例患者中共有92例携带与单证证型相关的突变基因,采用无监督层次聚类分析得到脾虚热毒证这一特征证型,该复合证型多有Hippo、TGF-β等信号通路的激活,表现为微卫星高度不稳定（MSI-H）和高肿瘤突变负荷（TMB）的特点。［结论］不同单证的胃癌患者具有不同的基因突变特征,脾气虚证多有PIK3CA、ARID1A、APC基因突变;新发胃癌患者多为虚实夹杂的复合证型,辨证为脾虚热毒证的胃癌患者可能是免疫治疗的适宜人群。     

Upfront Next Generation Sequencing in Non-Small Cell Lung Cancer

In advanced non-small cell lung cancer (NSCLC), patients with actionable genomic alterations may derive additional clinical benefit from targeted treatment compared to cytotoxic chemotherapy. Current guidelines recommend extensive testing with next generation sequencing (NGS) panels. We investigated the impact of using a targeted NGS panel (TruSight Tumor 15, Illumina) as reflex testing for NSCLC samples at a single institution. Molecular analysis examined 15 genes for hotspot mutation variants, including AKT1, BRAF, EGFR, ERBB2, FOXL2, GNA11, GNAQ, KIT, KRAS, MET, NRAS, PDGFRA, PIK3CA, RET and TP53 genes. Between February 2017 and October 2020, 1460 samples from 1395 patients were analyzed. 1201 patients (86.1%) had at least one variant identified, most frequently TP53 (47.5%), KRAS (32.2%) or EGFR (24.2%). Among these, 994 patients (71.3%) had clinically relevant variants eligible for treatment with approved therapies or clinical trial enrollment. The incremental cost of NGS beyond single gene testing (EGFR, ALK) was CAD $233 per case. Reflex upfront NGS identified at least one actionable variant in more than 70% of patients with NSCLC, with minimal increase in testing cost. Implementation of NGS panels remains essential as treatment paradigms continue to evolve.