Immunotherapy Comes of Age in Lung Cancer

Lung carcinoma is the leading cause of death by cancer worldwide. When possible, surgery is the best treatment strategy for patients with non–small-cell lung cancer. However, even with curative-intent therapy, most patients will develop local or systemic recurrence and, ultimately, succumb to their disease. In recent years, evidence on the role of the antitumor activity of the immune system and the understanding of tumor immunosurveillance have resulted in the emergence of immunotherapy as a promising therapeutic approach in lung cancer. The main approaches are immune checkpoint inhibition, such as blockade of the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1 receptors and the programmed cell death-1 ligand, and vaccine therapy, which elicits specific antitumor immunity against relevant tumor-associated antigens. We have reviewed recently reported results from clinical trials and the possible future role of vaccine therapy and immune checkpoint inhibition in the treatment of small cell lung cancer and non–small-cell lung cancer.     

免疫检查点PD-1／PD-L1通路在小细胞肺癌中的作用

小细胞肺癌（SCLC）主要的特点为生长迅速且早期易发生广泛转移。尽管SCLC对于化疗和放疗敏感,但几乎所有的患者均在治疗后发生复发转移,预后差。免疫检测点抑制剂,尤其程序化细胞死亡受体-1（PD-1）／程序化细胞死亡配体-1（PD-L1）拮抗剂在SCLC的临床前和临床研究中均获得了良好效果,并且能够延长患者生存。免疫检测点疗法作为一种新兴的方法在未来可能会改变SCLC治疗模式。此外,有限的数据显示出PD-L1表达可能成为筛选获益人群一个有效的生物标记物。本文总结PD-L1作为标记物的发展历程,并同时阐述PD-1／PD-L1抑制剂在SCLC治疗中的进展。     

Combination Therapy of Radiotherapy and Anti-PD-1/PD-L1 Treatment in Non–Small-cell Lung Cancer: A Mini-review

Immune checkpoint inhibitors against programmed cell death-1 (PD-1) or programmed cell death-ligand 1 (PD-L1) are a standard pharmacologic therapy for patients with non–small-cell lung cancer (NSCLC). Substantial data have accumulated in recent years showing that radiotherapy combined with immunotherapy is more effective than monotherapy alone. Preclinical studies have shown that PD-L1 expression is upregulated on tumor cells after radiotherapy, resulting in the synergistically enhanced antitumor effect of irradiation and PD-L1 blockade. In the clinical setting, patients receiving radiotherapy before anti-PD-1 treatment have had a significantly better prognosis than those who have not undergone radiotherapy. In the present report, we reviewed previous studies of the combination of radiotherapy and anti-PD-1/PD-L1 treatment for NSCLC. In addition, we report our case of a patient whose PD-L1 expression gradually increased in brain metastases from NSCLC after repeated radiotherapy. In the perspectives portion, we focused on the questions of how to integrate radiotherapy into anti-PD-1/PD-L1 agent regimens and described several ongoing clinical trials.     

The Significance of the PD-L1 Expression in Non–Small-Cell Lung Cancer: Trenchant Double Swords as Predictive and Prognostic Markers

Lung cancer is the leading cause of death due to cancer worldwide. Surgery, chemotherapy, and radiotherapy have been the standard treatment for lung cancer, and targeted molecular therapy has greatly improved the clinical course of patients with non–small-cell lung cancer (NSCLC) harboring driver mutations, such as in epidermal growth factor receptor and anaplastic lymphoma kinase genes. Despite advances in such therapies, the prognosis of patients with NSCLC without driver oncogene mutations remains poor. Immunotherapy targeting programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) has recently been shown to improve the survival in advanced NSCLC. The PD-L1 expression on the surface of tumor cells has emerged as a potential biomarker for predicting responses to immunotherapy and prognosis after surgery in NSCLC. However, the utility of PD-L1 expression as a predictive and prognostic biomarker remains controversial because of the existence of various PD-L1 antibodies, scoring systems, and positivity cutoffs. In this review, we summarize the data from representative clinical trials of PD-1/PD-L1 immune checkpoint inhibitors in NSCLC and previous reports on the association between PD-L1 expression and clinical outcomes in patients with NSCLC. Furthermore, we discuss the future perspectives of immunotherapy and immune checkpoint factors.     

程序性死亡受体1及程序性死亡受体配体1抑制剂在小细胞肺癌治疗中的进展

小细胞肺癌(SCLC)约占肺癌的15%,是一种神经内分泌肿瘤,生长迅速、极具侵袭性,容易早期发生远处转移。尽管SCLC对一线化疗敏感,但容易短时间内复发。在过去的5年间,免疫治疗在SCLC中取得了一定的成果,特别是在程序性死亡受体1和程序性死亡受体配体1方面,SCLC治疗模式已经发生改变。文章对免疫检查点抑制剂在SCLC中的探索研究做一综述,以期为广大临床工作者提供参考。     

PD-1/PD-L1在小细胞肺癌中的临床研究进展

小细胞肺癌（small cell lung cancer，SCLC）恶性程度高，具有强侵袭性、快速增长及早期转移等特点。初始治疗对化疗和放疗较敏感，但易复发且预后差。免疫检测点抑制剂程序性死亡分子-1（programmed death-1，PD-1）和程序性死亡分子1配体（pro? grammed death-ligand 1，PD-L1）拮抗剂，通过激活T细胞对肿瘤细胞的免疫应答，在SCLC的临床研究中均获得了很好的疗效，有望成为治疗SCLC的主要手段。本文旨在阐述PD-1/PD-L1抑制剂在SCLC治疗中的研究进展，同时，比较肿瘤突变负荷（tumor mutation burden，TMB）与PD-L1表达作为生物标记物在SCLC的作用。      

PD-1/PD-L1拮抗剂在小细胞肺癌治疗中的研究进展

小细胞肺癌是以广泛转移和预后不良为特征的一种恶性肿瘤。虽然34%~85%的小细胞肺癌对化疗有效,但疾病进展迅速,后续的二线治疗效果很不理想,并且近几十年的治疗方案没有突破性进展。近几年生物治疗迅速发展,免疫治疗成为继靶向治疗后的又一次飞跃。程序性死亡蛋白-1(PD-1)与程序性死亡受体-配体1(PD-L1)结合,抑制了CD4^+和CD8^+T细胞的增殖和活化,负性调控机体免疫机制应答过程,从而介导肿瘤细胞的免疫逃逸,促进肿瘤生长。PD-1/PD-L1拮抗剂在SCLC中的临床前及临床研究中均获得了良好效果,让更多的小细胞肺癌患者受益,尽可能的延长生存时间。本文就PD-1/PD-L1拮抗剂在小细胞肺癌中的研究进展作一综述。     

Combination Strategies on the Basis of Immune Checkpoint Inhibitors in Non–Small-Cell Lung Cancer: Where Do We Stand?

The era of immune checkpoint inhibitors, especially programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) antibodies in the treatment of advanced non–small-cell lung cancer (NSCLC) is coming. Because of the lack of the definite biomarkers to select the optimal responders, only approximately 20% of patients with advanced NSCLC would respond to single checkpoint inhibitors-based immunotherapy. Moreover, primary or acquired resistance to conventional therapies is inevitable in most cases. Thus, combinations are pushed to move forward to be an alternative strategy and surely, it would be a future direction. Combination approaches on the basis of PD-1/PD-L1 inhibitors are currently designed to re-energize the immune system with complementary/synergetic mechanisms and could achieve durable antineoplastic effects in NSCLC. Herein, we highlight the potential combinations on the basis of PD-1/PD-L1 inhibitors in NSCLC, with other immunotherapies, chemotherapy, radiotherapy, and targeted therapy in this current review.     

Small-Cell Carcinoma With an Epidermal Growth Factor Receptor Mutation in a Never-Smoker With Gefitinib-Responsive Adenocarcinoma of the Lung

Activating mutations in the epidermal growth factor receptor (EGFR) gene are extremely rare in small-cell lung cancer (SCLC). Here, we present a case of an EGFR-mutant gefitinib-responsive non–small-cell lung cancer (NSCLC) of adenocarcinoma histology occurring in a never-smoker followed by subsequent diagnosis of metastatic SCLC carrying an EGFR mutation. Although gefitinib therapy of the primary NSCLC resulted in disease control for over 3 years, the patient subsequently developed metastatic SCLC to the liver. Epidermal growth factor receptor mutation analysis revealed that the exon 21 L858R activating mutation was present in both the original lung adenocarcinoma and the metastatic SCLC. We hypothesize that SCLC either evolved from the previously diagnosed NSCLC or that both arose from a common precursor. Further comparative molecular analysis of these histologically distinct tumors would be of value to better understand the potential role of EGFR in the pathogenesis of SCLC in never-smokers, and the role of selection for an EGFR-mutant SCLC subclone as an unusual mechanism of acquired resistance to EGFR inhibitors in NSCLC.     

The changing diagnostic pathway for lung cancer patients in Shanghai,China

Accumulating evidence suggest that patients with advanced non–small-cell lung cancer (NSCLC) and specific genomic alterations including epidermal growth factor receptor and microtubule-associated protein-like 4 anaplastic lymphoma kinase could significantly benefit from molecular-targeted therapies compared with chemotherapy. Recently, immunotherapy based on programmed cell death 1 (PD-1) and its ligand (PD-L1) blockade prolong survival in patients with advanced NSCLC, especially in those patients with positive expression of PD-L1 and when used in the first-line setting. Therefore, the diagnosis, clinical staging and molecular genotyping must be quick and efficient so that we can make a timely and precise decision for treatment strategy. In our department, it takes a median 4 working days (range 3–6) for a new patient from initial respiratory consultation to treatment decision, whereas in many countries, 14 workdays is considered a reasonable timeline. In this article, we will provide detailed information on the diagnostic pathway for a new patient suspected of having lung cancer to the final treatment decisions in our department.     

Targeting the PD-1/PD-L1 axis in non–small cell lung cancer

The last decade has witnessed rapid advances in the discovery and development of immune checkpoint inhibitors in cancer medicine, particularly drugs targeting programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) in non–small cell lung cancer (NSCLC). The proven antitumor efficacy coupled with low rates of drug-related toxicities observed, albeit idiosyncratic, with these novel immunotherapeutics have led to the registration of multiple PD-1 and PD-L1 inhibitors, such as nivolumab, pembrolizumab, and atezolizumab, in second-line advanced NSCLC, whereas durvalumab and avelumab are in late-phase clinical testing. Moreover, pembrolizumab has shown a survival advantage in the first-line setting; however, nivolumab failed to show a survival benefit possibly relating to patient selection based on PD-L1 expression. Current patient selection is based on PD-L1 expression, using the relevant companion diagnostic test, where patients with strong PD-L1 expression being more likely to respond to these novel agents. Ongoing clinical research focuses on the development of PD-1 and PD-L1 inhibitor monotherapy in neoadjuvant and adjuvant NSCLC. There is also much interest in using these drugs as a therapeutic backbone for rational combinations with other treatment modalities including cytotoxic chemotherapies in the first-line NSCLC, other immunotherapies such as cytotoxic T-lymphocyte–associated protein 4 antagonists, molecularly targeted agents including EGFR and ALK inhibitors, and radiotherapy. Concurrent treatment with radiotherapy is of particular interest owing to the potential for the abscopal effect, using radiotherapy to facilitate systemic treatment.     

The anticancer immune response of anti-PD-1/PD-L1 and the genetic determinants of response to anti-PD-1/PD-L1 antibodies in cancer patients

The programmed death-1 (PD-1), a coinhibitory receptor expressed on activated T cells and B cells, is demonstrated to induce an immune-mediated response and play a critical role in tumor initiation and development. The cancer patients harboring PD-1 or PD ligand 1 (PD-L1) protein expression have often a poor prognosis and clinical outcome. Currently, targeting PD-1 pathway as a potential new anticancer strategy is attracting more and more attention in cancer treatment. Several monoclonal antibodies against PD-1 or PD-L1 have been reported to enhance anticancer immune responses and induce tumor cell death. Nonetheless, the precise molecular mechanisms by which PD-1 affects various cancers remain elusive. Moreover, this therapy is not effective for all the cancer patients and only a fraction of patients respond to the antibodies targeting PD-1 or PD-L1, indicating these antibodies may only works in a subset of certain cancers. Thus, understanding the novel function of PD-1 and genetic determinants of response to anti-PD-1 therapy will allow us to develop a more effective and individualized immunotherapeutic strategy for cancer.     

A Phase II Study of Nivolumab in Patients With Advanced Non–small-cell Lung Cancer who Responded to Prior PD-1/L1 Inhibitors: West Japan Oncology Group 9616L (WJOG9616L)

Immune-checkpoint inhibitors (ICIs) play an important role in treatment for advanced non–small-cell lung cancer. Over one-half of patients, however, have relapse. Although rechallenge treatment of anti-cancer drugs that showed efficacy in prior lines of therapy has been broadly accepted in lung cancer, evidence of efficacy of rechallenge of ICIs has been limited to anecdotal case series. We therefore plan a phase II study. The primary endpoint is to assess the overall response rate of nivolumab in patients with advanced non–small-cell lung cancer who responded to prior ICIs. Secondary endpoints are disease control rate, progression-free survival, overall survival, and safety. Sixty patients will be enrolled in this trial. Programmed death-ligand 1 expression level in circulating tumor cells will be evaluated as a surrogate biomarker for the prediction of the efficacy.     

Immunotherapy for LELC: Case Report and a Focused Review

Lymphoepithelioma-like carcinoma of the lung (LELC) is a rare, Epstein-Barr virus-associated tumor. LELC occurs mostly in young, Asian nonsmokers. A few hundred cases have been reported, mostly from retrospective Asian studies. Optimal treatment has not been clearly established. Treatment options are based on surgery for early stage and on cisplatin-based chemotherapy as first-line therapy for metastatic disease. Prognosis may seem better than for other types of non–small-cell lung cancer, but it remains poor in advanced disease, with a median survival of 24 months, and new treatments options are still warranted. Immunotherapies are now key players in the treatment of non–small-cell lung cancer. However, few data are available for this rare histologic subgroup. We have reviewed the available data on LELC with a focus on the first few cases reported with a response to a programmed cell death 1 inhibitor.     

A Randomized Phase II Study Comparing Nivolumab With Carboplatin-Pemetrexed for Patients With EGFR Mutation–Positive Nonsquamous Non–Small-Cell Lung Cancer Who Acquire Resistance to Tyrosine Kinase Inhibitors Not Due to a Secondary T790M Mutation: Rationale and Protocol Design for the WJOG8515L Study

Antibodies to programmed cell death–1 (PD-1), such as nivolumab, have shown promising clinical activity in patients with advanced non–small-cell lung cancer (NSCLC), but their efficacy appears to be less pronounced in patients with such tumors harboring epidermal growth factor receptor gene (EGFR) mutations. Recent findings suggest that patients with EGFR mutation–positive NSCLC who develop resistance to tyrosine kinase inhibitors (TKIs) due to mechanisms other than acquisition of the secondary T790M mutation of EGFR are more likely to benefit from nivolumab treatment, possibly as a result of a higher level of expression of the PD-1 ligand PD-L1, than are patients who are T790M-positive. The WJOG8515L study (UMIN ID: 000021133) is a randomized phase II trial to compare nivolumab with the combination of carboplatin and pemetrexed in patients with EGFR mutation–positive nonsquamous NSCLC who have developed resistance to EGFR-TKIs due to mechanisms other than T790M. Eligible patients are those with stage IV or recurrent EGFR mutation–positive NSCLC who experience disease progression after therapy with more than 1 EGFR-TKI, including gefitinib, erlotinib, or afatinib; they must show no evidence of the T790M mutation on analysis of a tumor biopsy specimen obtained after progression on such EGFR-TKI therapy, or, if T790M is detected, they must again experience progression on subsequent treatment with a third-generation EGFR-TKI. The primary endpoint is progression-free survival (PFS), and secondary end points include overall survival (OS), objective response rate, duration of response, safety, and OS and PFS according to PD-L1 expression level. Recruitment started in May 2016 and is ongoing.     

PD-1/PD-L1在非小细胞肺癌中的临床研究进展

近年来,免疫治疗在癌症研究中取得了突飞猛进的发展。以程序性死亡受体-1（programmed cell death-1,PD-1）及其配体程序性死亡配体-1（programmed cell death-ligand 1,PD-L1）为靶点的免疫治疗药物在非小细胞肺癌（non-small cell lung cancer,NSCLC）的治疗中显示出了良好的疗效和耐受性,治疗前景值得期待。本文对PD-1/PD-L1治疗NSCLC的临床研究现状进行综述。      

PD-1/PD-L1抑制剂在前列腺癌免疫治疗中的研究进展

前列腺癌（prostate cancer,PCa）发病率呈逐年上升趋势,前列腺癌免疫治疗已成为继外科、放疗、化疗之后的第四种治疗方法。作为当今肿瘤免疫治疗领域最具有研究前景的免疫检查点抑制剂中的程序性死亡受体-1（programmed cell death-1,PD-1）/程序性死亡配体-1（programmed cell death-ligand1,PD-L1）抑制剂,通过阻断PD-1与其配体PD-L1结合,从而终止T细胞的负性调控信号,使T细胞的活性恢复,进而逆转肿瘤免疫逃逸机制,恢复自身免疫应答,最后起到抑制和杀伤肿瘤的作用。本文就目前应用于前列腺癌临床试验的PD-1/PD-L1抑制剂的现况和临床疗效研究进展进行综述。      

Left Behind? Drug Discovery in Extensive-Stage Small-Cell Lung Cancer

Systemic therapy and subsequent survival for patients with extensive-stage small-cell lung cancer (SCLC) are poor and have remained unchanged in the past quarter century. To improve outcomes in these patients, a new drug development paradigm must be adopted that moves away from empiricism and instead focuses on tumor biology and heterogeneity as a means to increase target and drug class diversity. By incorporating tools that have led to new diagnostic and treatment options in non–small-cell lung cancer, there could be hope yet for the future of SCLC therapeutics.     

Cancer vaccines for the treatment and prevention of non small-cell lung cancer

Cancer vaccines targeting non small-cell lung cancer (NSCLC) have been studied for decades; clinical trials, for the most part, have focused on the use of autologous and allogeneic whole-tumor cell vaccines. Recent advances in molecular biology and immunology, however, have allowed the identification of many tumor antigens involved in the generation of immunity to NSCLC. Although small-cell lung cancer (SCLC) is commonly thought of as an immunogenic tumor, it is now clear that NSCLC is also capable of eliciting an endogenous immune response in patients with the disease and, in fact, has a natural history that may make NSCLC more amenable to vaccine therapy as an adjuvant treatment strategy. This review will high-light the major components of the immune system that may potentially interact with tumor-associated proteins as well as outline the immunologic similarities and differences between SCLC and NSCLC. Tumor antigens that elicit immune responses in patients with NSCLC will be discussed. Finally, clinical trials of whole-tumor cell vaccines, both autologous and allogeneic, and tumor antigen-specific vaccines will also be discussed.