A peptide antigen derived from EGFR T790M is immunogenic in non‑small cell lung cancer

Expansion of tumor-infiltrating lymphocytes in non-small cell lung cancer: Clinical potential and efficacy in EGFR mutation subsets

Our study aimed to expand tumor-infiltrating lymphocytes (TILs) from primary non-small cell lung cancers (NSCLCs) and evaluate their reactivity against tumor cells. We expanded TILs from 103 primary NSCLCs using histopathological analysis, flow cytometry, IFN-γ release assays, cell-mediated cytotoxicity assays, and in vivo efficacy tests. TIL expansion was observed in all cases, regardless of EGFR mutation status. There was also an increase in the median CD4+/CD8+ ratio during expansion. In post-rapid expansion protocol (REP) TILs, 13 out of 16 cases, including all three cases with EGFR mutations, exhibited a two-fold or greater increase in IFN-γ secretion. The cytotoxicity assay revealed enhanced tumor cell death in three of the seven cases, two of which had EGFR mutations. In vivo functional testing in a patient-derived xenograft model showed a reduction in tumor volume. The anti-tumor activity of post-REP TILs underscores their potential as a therapeutic option for advanced NSCLC, irrespective of mutation status.

Epidermal Growth Factor Receptor-Targeted Neoantigen Peptide Vaccination for the Treatment of Non-Small Cell Lung Cancer and Glioblastoma

The epidermal growth factor receptor (EGFR) plays crucial roles in several important biological functions such as embryogenesis, epithelial tissue development, and cellular regeneration. However, in multiple solid tumor types overexpression and/or activating mutations of the EGFR gene frequently occur, thus hijacking the EGFR signaling pathway to promote tumorigenesis. Non-small cell lung cancer (NSCLC) tumors in particular often contain prevalent and shared EGFR mutations that provide an ideal source for public neoantigens (NeoAg). Studies in both humans and animal models have confirmed the immunogenicity of some of these NeoAg peptides, suggesting that they may constitute viable targets for cancer immunotherapies. Peptide vaccines targeting mutated EGFR have been tested in multiple clinical trials, demonstrating an excellent safety profile and encouraging clinical efficacy. For example, the CDX-110 (rindopepimut) NeoAg peptide vaccine derived from the EGFRvIII deletion mutant in combination with temozolomide and radiotherapy has shown efficacy in treating EGFRvIII-harboring glioblastoma multiforme (GBM) patients undergone surgery in multiple Phase I and II clinical trials. Furthermore, pilot clinical trials that have administered personalized NeoAg peptides for treating advanced-stage NSCLC patients have shown this approach to be a feasible and safe method to increase antitumor immune responses. Amongst the vaccine peptides administered, EGFR mutation-targeting NeoAgs induced the strongest T cell-mediated immune responses in patients and were also associated with objective clinical responses, implying a promising future for NeoAg peptide vaccines for treating NSCLC patients with selected EGFR mutations. The efficacy of NeoAg-targeting peptide vaccines may be further improved by combining with other modalities such as tyrosine kinase or immune checkpoint inhibitor (ICI) therapy, which are currently being tested in animal models and clinical trials. Herein, we review the most current basic and clinical research progress on EGFR-targeted peptide vaccination for the treatment of NSCLC and other solid tumor types.

DMU-212 against EGFR-mutant non-small cell lung cancer via AMPK/PI3K/Erk signaling pathway

Although some important advances have been achieved in clinical and diagnosis in the past few years, the management of non-small cell lung cancer (NSCLC) is ultimately dissatisfactory due to the low overall cure and survival rates. Epidermal growth factor (EGFR) has been recognized as a carcinogenic driver and is a crucial pharmacological target for NSCLC. DMU-212, an analog of resveratrol, has been reported to have significant inhibitory effects on several types of cancer. However, the effect of DMU-212 on lung cancer remains unclear. Therefore, this study aims to determine the effects and underlying mechanism of DMU-212 on EGFR-mutant NSCLC cells. The data found that the cytotoxicity of DMU-212 on three EGFR-mutant NSCLC cell lines was significantly higher than that of normal lung epithelial cell. Further study showed that DMU-212 can regulate the expression of cell cycle-related proteins including p21 and cyclin B1 to induce G2/M phase arrest in both H1975 and PC9 cells. Moreover, treatment with DMU-212 significantly promoted the activation of AMPK and simultaneously down-regulated the expression of EGFR and the phosphorylation of PI3K, Akt and ERK. In conclusion, our study suggested that DMU-212 inhibited the growth of NSCLCs via targeting of AMPK and EGFR.

Deep CNN Model Using CT Radiomics Feature Mapping Recognizes EGFR Gene Mutation Status of Lung Adenocarcinoma

To recognize the epidermal growth factor receptor (EGFR) gene mutation status in lung adenocarcinoma (LADC) has become a prerequisite of deciding whether EGFR-tyrosine kinase inhibitor (EGFR-TKI) medicine can be used. Polymerase chain reaction assay or gene sequencing is for measuring EGFR status, however, the tissue samples by surgery or biopsy are required. We propose to develop deep learning models to recognize EGFR status by using radiomics features extracted from non-invasive CT images. Preoperative CT images, EGFR mutation status and clinical data have been collected in a cohort of 709 patients (the primary cohort) and an independent cohort of 205 patients. After 1,037 CT-based radiomics features are extracted from each lesion region, 784 discriminative features are selected for analysis and construct a feature mapping. One Squeeze-and-Excitation (SE) Convolutional Neural Network (SE-CNN) has been designed and trained to recognize EGFR status from the radiomics feature mapping. SE-CNN model is trained and validated by using 638 patients from the primary cohort, tested by using the rest 71 patients (the internal test cohort), and further tested by using the independent 205 patients (the external test cohort). Furthermore, SE-CNN model is compared with machine learning (ML) models using radiomics features, clinical features, and both features. EGFR(-) patients show the smaller age, higher odds of female, larger lesion volumes, and lower odds of subtype of acinar predominant adenocarcinoma (APA), compared with EGFR(+). The most discriminative features are for texture (614, 78.3%) and the features of first order of intensity (158, 20.1%) and the shape features (12, 1.5%) follow. SE-CNN model can recognize EGFR mutation status with an AUC of 0.910 and 0.841 for the internal and external test cohorts, respectively. It outperforms the CNN model without SE, the fine-tuned VGG16 and VGG19, three ML models, and the state-of-art models. Utilizing radiomics feature mapping extracted from non-invasive CT images, SE-CNN can precisely recognize EGFR mutation status of LADC patients. The proposed method combining radiomics features and deep leaning is superior to ML methods and can be expanded to other medical applications. The proposed SE-CNN model may help make decision on usage of EGFR-TKI medicine.

The Immunogenic Potential of Recurrent Cancer Drug Resistance Mutations: An In Silico Study

Cancer somatic mutations have been identified as a source of antigens that can be targeted by cancer immunotherapy. In this work, expanding on previous studies, we analyze the HLA-presentation properties of mutations that are known to drive resistance to cancer targeted-therapies. We survey a large dataset of mutations that confer resistance to different drugs and occur in numerous genes and tumor types. We show that a significant number of them are predicted in silico to be potentially immunogenic across a large proportion of the human population. Further, by analyzing a cohort of patients carrying a small subset of these resistance mutations, we provide evidence that what is observed in the general population may be indicative of the mutations' immunogenic potential in resistant patients. Two of the mutations in our dataset had previously been experimentally validated by others and it was confirmed that some of their associated neopeptides elicit T-cell responses in vitro. The identification of potent cancer-specific antigens can be instrumental for developing more effective immunotherapies. In this work, we propose a novel list of drug-resistance mutations, several of which are recurrent, that could be of particular interest in the context of off-the-shelf precision immunotherapies such as therapeutic cancer vaccines.

Identification of Clonal Neoantigens Derived From Driver Mutations in an EGFR-Mutated Lung Cancer Patient Benefitting From Anti-PD-1

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been recommended as the first-line therapy for non-small cell lung cancer (NSCLC) patients harboring EGFR mutations. However, acquired resistance to EGFR-TKIs is inevitable. Although immune checkpoint blockades (ICBs) targeting the programmed cell death 1 (PD-1)/PD-ligand (L)1 axis have achieved clinical success for many cancer types, the clinical efficacy of anti-PD-1/PD-L1 blockades in EGFR mutated NSCLC patients has been demonstrated to be lower than those without EGFR mutations. Here, we reported an advanced NSCLC patient with EGFR driver mutations benefitting from anti-PD-1 blockade therapy after acquiring resistance to EGFR-TKI. We characterized the mutational landscape of the patient with next-generation sequencing (NGS) and successfully identified specific T-cell responses to clonal neoantigens encoded by EGFR exon 19 deletion, TP53 A116T and DENND6B R398Q mutations. Our findings support the potential application of immune checkpoint blockades in NSCLC patients with acquired resistance to EGFR-TKIs in the context of specific clonal neoantigens with high immunogenicity. Personalized immunomodulatory therapy targeting these neoantigens should be explored for better clinical outcomes in EGFR mutated NSCLC patients.

Efficacy of immunotherapy targeting the neoantigen derived from epidermal growth factor receptor T790M/C797S mutation in non-small cell lung cancer

Lung cancer is the leading cause of cancer‐related deaths worldwide. Epidermal growth factor receptor‐tyrosine kinase inhibitors (EGFR‐TKI) often have good clinical activity against non–small cell lung cancer (NSCLC) with activating EGFR mutations. Osimertinib, which is a third‐generation EGFR‐TKI, has a clinical effect even on NSCLC harboring the threonine to methionine change at codon 790 of EGFR (EGFR T790M) mutation that causes TKI resistance. However, most NSCLC patients develop acquired resistance to osimertinib within approximately 1 year, and 40% of these patients have the EGFR T790M and cysteine to serine change at codon 797 (C797S) mutations. Therefore, there is an urgent need for the development of novel treatment strategies for NSCLC patients with the EGFR T790M/C797S mutation. In this study, we identified the EGFR T790M/C797S mutation‐derived peptide (790‐799) (MQLMPFGSLL) that binds the human leukocyte antigen (HLA)‐A*02:01, and successfully established EGFR T790M/C797S‐peptide‐specific CTL clones from human PBMC of HLA‐A2 healthy donors. One established CTL clone demonstrated adequate cytotoxicity against T2 cells pulsed with the EGFR T790M/C797S peptide. This CTL clone also had high reactivity against cancer cells that expressed an endogenous EGFR T790M/C797S peptide using an interferon‐γ (IFN‐γ) enzyme‐linked immunospot (ELISPOT) assay. In addition, we demonstrated using a mouse model that EGFR T790M/C797S peptide‐specific CTL were induced by EGFR T790M/C797S peptide vaccine in vivo. These findings suggest that an immunotherapy targeting a neoantigen derived from EGFR T790M/C797S mutation could be a useful novel therapeutic strategy for NSCLC patients with EGFR‐TKI resistance, especially those resistant to osimertinib.

Endoplasmic Reticulum-Associated Degradation-Dependent Processing in Cross-Presentation and Its Potential for Dendritic Cell Vaccinations: A Review

While the success of dendritic cell (DC) vaccination largely depends on cross-presentation (CP) efficiency, the precise molecular mechanism of CP is not yet characterized. Recent research revealed that endoplasmic reticulum (ER)-associated degradation (ERAD), which was first identified as part of the protein quality control system in the ER, plays a pivotal role in the processing of extracellular proteins in CP. The discovery of ERAD-dependent processing strongly suggests that the properties of extracellular antigens are one of the keys to effective DC vaccination, in addition to DC subsets and the maturation of these cells. In this review, we address recent advances in CP, focusing on the molecular mechanisms of the ERAD-dependent processing of extracellular proteins. As ERAD itself and the ERAD-dependent processing in CP share cellular machinery, enhancing the recognition of extracellular proteins, such as the ERAD substrate, by ex vivo methods may serve to improve the efficacy of DC vaccination.

Osimertinib and other third-generation EGFR TKI in EGFR-mutant NSCLC patients

Osimertinib was the first third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) to receive FDA and EMA approval for metastatic EGFR-mutant non-small-cell lung cancer (NSCLC) patients that have acquired the EGFR T790M resistance mutation. Clinical trials have demonstrated the efficacy of osimertinib in this patient population and clinical trials of other third-generation EGFR TKI are currently under way. Additional challenges in this patient population, such as the upfront efficacy of osimertinib, validation of T790M in liquid biopsies as a dynamic predictive marker of efficacy, along with combination with immune checkpoint inhibitors are being explored, representing an extraordinary time of development for EGFR-mutant NSCLC.

Strategies to overcome acquired resistance to EGFR TKI in the treatment of non-small cell lung cancer

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) represents a paradigm shift in the treatment of non-small cell lung cancer (NSCLC) patients and has been the first-line therapy in clinical practice. While erlotinib, gefitinib and afatinib have achieved superior efficacy in terms of progression-free survival and overall survival compared with conventional chemotherapy in NSCLC patients, most people inevitably develop acquired resistance to them, which presents another challenge in the treatment of NSCLC. The mechanisms of acquired resistance can be classified as three types: target gene mutation, bypass signaling pathway activation and histological transformation. And the most common mechanism is T790M which accounts for approximately 50% of all subtypes. Many strategies have been explored to overcome the acquired resistance to EGFR TKI. Continuation of EGFR TKI beyond progressive disease is confined to patients in asymptomatic stage when the EGFR addiction is still preserved in some subclones. While the combination of EGFR TKI and chemotherapy or other targeted agents has improved the survival benefit in EGFR TKI resistant patients, there are controversies within them. The next-generation EGFR TKI and immunotherapy represent two novel directions for overcoming acquired resistance and have achieved promising efficacy. Liquid biopsy provides surveillance of the EGFR mutation by disclosing the entire genetic landscape but tissue biopsy is still indispensable because of the considerable rate of false-negative plasma.

The antitumor activity screening of chemical constituents from Camellia nitidissima Chi

Chemotherapy is the preferred and most common treatment for cancer in clinical practice. An increasing number of researchers all over the world are focusing on natural medicines to find new antitumor drugs, and several reports have shown that Camellia nitidissima (C. nitidissima) Chi could reduce blood-lipid, decrease blood pressure, resist oxidation, prevent carcinogenesis and inhibit tumors. Therefore, the pharmacodynamics of the chemical constituents in C. nitidissima need to be investigated further. In the present study, 16 chemical constituents were isolated from the leaves of C. nitidissima, of which 6 compounds are reported to be found in this plant for the first time. Furthermore, all these phytochemicals were screened for antitumor activity on 4 common cancer cell lines, while compound 3, one oleanane-type triterpene, exhibited the most potential antitumor effects. Interestingly, to our knowledge, this was the first report that compound 3 inhibits cancer cells. Compound 3 inhibited EGFR-mutant lung cancer cell line, NCI-H1975 via apoptosis effect, with an IC50 of 13.37±2.05 µM at 48 h. Based on the data, compound 3 showed potential for antitumor drug development, suggesting the scientific basis for the antitumor activity of C. nitidissima.

Immune Responses to Epidermal Growth Factor Receptor (EGFR) and Their Application for Cancer Treatment

Epidermal growth factor receptor (EGFR) is a prototypic cell-surface receptor belonging to the ErbB/HER onocogene family. Overexpression or somatic mutations of EGFR have been reported to play an important role in tumorigenesis in various types of epithelial cancers. Therefore, targeting of EGFR with specific blocking antibodies or inhibitors have been developing for treatment for EGFR-associated tumors. Immune responses to HER2, another molecule of the ErbB/HER onocogene family, have been well studied, but only limited information on the immune responses to EGFR in cancer has been currently available. In this review, we have summarized the available data and discussed potential clinical importance of the anti-EGFR immune responses and EGFR-mediated immune regulation in cancer. Several lines of evidence suggest that cellular and humoral immune responses to EGFR might be useful as a marker and/or target for cancer therapy against EGFR-associated tumors. In addition, recent studies suggest the critical roles of EGFR-mediated signaling in regulation of expression of an immune checkpoint molecule, programmed death-ligand 1 (PD-L1) in tumor cells. Further studies are warranted to clarify the impact of the anti-EGFR immune responses and EGFR-mediated immunomodulation for clinical application for cancer treatment.

Novel cancer antigens for personalized immunotherapies: latest evidence and clinical potential

The clinical success of monoclonal antibody immune checkpoint modulators such as ipilimumab, which targets cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), and the recently approved agents nivolumab and pembrolizumab, which target programmed cell death receptor 1 (PD-1), has stimulated renewed enthusiasm for anticancer immunotherapy, which was heralded by Science as 'Breakthrough of the Year' in 2013. As the potential of cancer immunotherapy has been recognized since the 1890s when William Coley showed that bacterial products could be beneficial in cancer patients, leveraging the immune system in the treatment of cancer is certainly not a new concept; however, earlier attempts to develop effective therapeutic vaccines and antibodies against solid tumors, for example, melanoma, frequently met with failure due in part to self-tolerance and the development of an immunosuppressive tumor microenvironment. Increased knowledge of the mechanisms through which cancer evades the immune system and the identification of tumor-associated antigens (TAAs) and negative immune checkpoint regulators have led to the development of vaccines and monoclonal antibodies targeting specific tumor antigens and immune checkpoints such as CTLA-4 and PD-1. This review first discusses the established targets of currently approved cancer immunotherapies and then focuses on investigational cancer antigens and their clinical potential. Because of the highly heterogeneous nature of tumors, effective anticancer immunotherapy-based treatment regimens will likely require a personalized combination of therapeutic vaccines, antibodies and chemotherapy that fit the specific biology of a patient's disease.