Beyond PD-L1 Markers for Lung Cancer Immunotherapy

Microbiome bacterial influencers of host immunity and response to immunotherapy

The gut microbiota influences anti-tumor immunity and can induce or inhibit response to immune checkpoint inhibitors (ICIs). Therefore, microbiome features are being studied as predictive/prognostic biomarkers of patient response to ICIs, and microbiome-based interventions are attractive adjuvant treatments in combination with ICIs. Specific gut-resident bacteria can influence the effectiveness of immunotherapy; however, the mechanism of action on how these bacteria affect anti-tumor immunity and response to ICIs is not fully understood. Nevertheless, early bacterial-based therapeutic strategies have demonstrated that targeting the gut microbiome through various methods can enhance the effectiveness of ICIs, resulting in improved clinical responses in patients with a diverse range of cancers. Therefore, understanding the microbiota-driven mechanisms of response to immunotherapy can augment the success of these interventions, particularly in patients with treatment-refractory cancers.

Gut microbiome and cancer implications: Potential opportunities for fermented foods

There is a critical opportunity to improve response to immunotherapies and overall cancer survivorship via dietary interventions targeted to modify the gut microbiome, and in turn, potentially enhance anti-cancer immunity. A promising dietary intervention is fermented foods, which may alter gut microbiome composition and, in turn, improve immunity. In this article, we summarize the state of the literature pertaining to the gut microbiome and response to immunotherapy and other cancer treatments, potential clinical implications of utilizing a fermented foods dietary approach to improve cancer treatment outcomes, and existing gaps in the literature regarding the implementation of fermented food interventions among individuals with cancer or with a history of cancer. This review synthesizes a compelling rationale across different disciplines to lay a roadmap for future fermented food dietary intervention research aimed at modulating the gut microbiome to reduce cancer burden.

Lung microbiome: an emerging player in lung cancer pathogenesis and progression

The microbiome of the lungs, although until recently neglected, is now emerging as a potential contributor to chronic lung diseases, including cancer. Preclinical evidence suggests that the microbial burden of the lungs shapes the host immunity mechanisms and affects local antitumor immune responses. Studies of cohorts of patients with lung cancer reveal that different microbiome profiles are detected in patients with lung cancer compared to controls. In addition, an association between differential lung microbiome composition and distinct responses to immunotherapy has been suggested, yet, with limited data. Scarce evidence exists on the role of the lung microbiome in the development of metastases in the lungs. Interestingly, the lung microbiome is not isolated and interacts with the gut microbiome through a dynamic axis. Future research on the involvement of the lung microbiome in lung cancer pathogenesis and potential therapeutic implications is greatly anticipated.

Targeting YAP/TAZ in Combination with PD-L1 Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer (NSCLC)

The survival of non-small cell lung cancer (NSCLC) patients has improved in the last decade as a result of introducing new therapeutics, such as immune checkpoint inhibitors, in the clinic. Still, some NSCLC patients do not benefit from these therapies due to intrinsic resistance or the development of acquired resistance and their malignant disease progresses. Further research on the molecular underpinnings of NSCLC pathobiology is required in order to discover clinically relevant molecular targets that regulate tumor immunity and to develop reasonable therapeutic combinations that will promote the efficacy of immune checkpoint inhibitors. Yes-associated Protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), the final effectors of the Hippo signaling transduction pathway, are emerging as key players in NSCLC development and progression. Herein, we overview studies that have investigated the oncogenic role of YAP/TAZ in NSCLC, focusing on immune evasion, and highlight the therapeutic potential of combining YAP/TAZ inhibitory agents with immune checkpoint inhibitors for the management of NSCLC patients.

The Role of Microbiota-Derived Vitamins in Immune Homeostasis and Enhancing Cancer Immunotherapy

Not all cancer patients who receive immunotherapy respond positively and emerging evidence suggests that the gut microbiota may be linked to treatment efficacy. Though mechanisms of microbial contributions to the immune response have been postulated, one likely function is the supply of basic co-factors to the host including selected vitamins. Bacteria, fungi, and plants can produce their own vitamins, whereas humans primarily obtain vitamins from exogenous sources, yet despite the significance of microbial-derived vitamins as crucial immune system modulators, the microbiota is an overlooked source of these nutrients in humans. Microbial-derived vitamins are often shared by gut bacteria, stabilizing bioenergetic pathways amongst microbial communities. Compositional changes in gut microbiota can affect metabolic pathways that alter immune function. Similarly, the immune system plays a pivotal role in maintaining the gut microbiota, which parenthetically affects vitamin biosynthesis. Here we elucidate the immune-interactive mechanisms underlying the effects of these microbially derived vitamins and how they can potentially enhance the activity of immunotherapies in cancer.

Impact of Gut Dysbiosis on the Risk of Non-Small-Cell Lung Cancer

Background: The imbalance of gut microbiota, dysbiosis, is associated with various malignant diseases. This study aimed to identify the characteristics of gut microbiota in age-matched treatment-naïve non-small-cell lung cancer (NSCLC) patients and healthy individuals to investigate possible gut-microbe-related pathways involved in the development of NSCLC. Methods: We enrolled 34 age-matched NSCLC patients and 268 healthy individuals. Hypervariable V3−V4 amplicons of 16S rRNA in freshly collected fecal samples were sequenced. Diversity, microbial composition, functional pathways, smoking history, and gut-microbe-related comorbidities were analyzed to assess the factors associated with the risk of NSCLC. Results: Microbial alpha diversity was decreased in the patients with NSCLC, and beta diversity was significantly different between the patients and controls (p < 0.001). After adjustments for sex, smoking history, hypertension, diabetes mellitus, chronic obstructive pulmonary disease, and 11 abundant microbes with significant differences between the patients and controls, the enrichment of Anaerotruncus spp. and Bacteroides caccae was associated with an increased risk of NSCLC (p = 0.003 and 0.007, respectively). The areas under receiver operating characteristic curves were 71.4% and 66.9% for Anaerotruncus spp. and Bacteroides caccae, respectively (both p < 0.001). Furthermore, the abundance of Bacteroides caccae was positively correlated with steroid hormone biosynthesis (p < 0.001), N-glycan biosynthesis (p = 0.023), glycosaminoglycan degradation (p < 0.001), lipoic acid metabolism (p = 0.039), peroxisome (p < 0.001), and apoptosis (p < 0.001), but inversely related to glycerolipid metabolism (p < 0.001). Anaerotruncus spp. was positively associated with decreased biosynthesis of ansamycin only (p = 0.001). No overlapping signaling pathways were modulated by Bacteroides caccae or Anaerotruncus spp. Conclusions: Our results revealed that fecal Anaerotruncus spp. and Bacteroides caccae were abundant and may be associated with the risk of NSCLC regardless of sex, smoking history, and gut-microbe-related comorbidities. Further investigations on the mechanism underlying the potential association between gut dysbiosis and the development of NSCLC are warranted.

Interactions between Dietary Micronutrients, Composition of the Microbiome and Efficacy of Immunotherapy in Cancer Patients

The effectiveness of immunotherapy in cancer patients depends on the activity of the host's immune system. The intestinal microbiome is a proven immune system modulator, which plays an important role in the development of many cancers and may affect the effectiveness of anti-cancer therapy. The richness of certain bacteria in the gut microbiome (e.g., Bifidobacterium spp., Akkermanisa muciniphila and Enterococcus hire) improves anti-tumor specific immunity and the response to anti-PD-1 or anti-PD-L1 immunotherapy by activating antigen-presenting cells and cytotoxic T cells within the tumor. Moreover, micronutrients affect directly the activities of the immune system or regulate their function by influencing the composition of the microbiome. Therefore, micronutrients can significantly influence the effectiveness of immunotherapy and the development of immunorelated adverse events. In this review, we describe the relationship between the supply of microelements and the abundance of various bacteria in the intestinal microbiome and the effectiveness of immunotherapy in cancer patients. We also point to the function of the immune system in the case of shifts in the composition of the microbiome and disturbances in the supply of microelements. This may in the future become a therapeutic target supporting the effects of immunotherapy in cancer patients.

Identification of Malassezia globosa as a Gastric Fungus Associated with PD-L1 Expression and Overall Survival of Patients with Gastric Cancer

BACKGROUND

Microbiotas affected the prognosis of cancer patients by regulating programmed death ligand-1 (PD-L1) expression. However, the relationship between gastric fungi and PD-L1 expression is still unclear in gastric cancer (GC). We aimed at exploring the association of gastric fungi with PD-L1 expression and overall survival in GC.

METHODS

A total of 61 GC patients were divided into the two groups based on the PD-L1 combined positive scores (CPS). Fungal profiling was performed by internal transcribed spacer rDNA sequencing, and the survival analyses were performed by Kaplan-Meier curves.

RESULTS

We observed a taxonomic difference of fungi between the PD-L1-High (CPS ≥ 10) and PD-L1-Low group (CPS < 10) by principal coordinates analysis (PCoA) (P = 0.014 for Bray-Curtis and P = 0.042 for Jaccard). Malassezia had a higher abundance in the PD-L1-High group compared to the PD-L1-Low group (P = 0.045). Malassezia globosa elevated significantly in the PD-L1-High group. GC patients with PD-L1 low expression and low abundance of Malassezia globosa had a longer overall survival (OS) than others (P = 0.047). Malassezia globosa was associated with PD-L1 expression (Odds Ratio = 3.509, 95% Confidence Interval: 1.056-11.656, P = 0.040). Malassezia globosa was associated with the tumor size (P = 0.031) and PD-L1 status (P = 0.024). GC patients with a high abundance of Malassezia globosa had shorter OS than others (P = 0.028). Malassezia globosa was an independent factor (Hazard Ratio = 3.080, 95% Confidence Interval: 1.140-8.323, P = 0.027) for OS after adjusting for tumor stage. Malassezia globosa was figured out to be associated with- fatty acid and lipid biosynthesis and degradation via LIPASYN pathway. Conclusions. Malassezia globosa was identified as a PD-L1 expression-associated gastric fungus and associated with OS of GC patients, which calls for more studies to further explore its potential in PD-L1/PD-1 targeted immunotherapy.

Multiplex Immunofluorescence and the Digital Image Analysis Workflow for Evaluation of the Tumor Immune Environment in Translational Research

A robust understanding of the tumor immune environment has important implications for cancer diagnosis, prognosis, research, and immunotherapy. Traditionally, immunohistochemistry (IHC) has been regarded as the standard method for detecting proteins in situ, but this technique allows for the evaluation of only one cell marker per tissue sample at a time. However, multiplexed imaging technologies enable the multiparametric analysis of a tissue section at the same time. Also, through the curation of specific antibody panels, these technologies enable researchers to study the cell subpopulations within a single immunological cell group. Thus, multiplexed imaging gives investigators the opportunity to better understand tumor cells, immune cells, and the interactions between them. In the multiplexed imaging technology workflow, once the protocol for a tumor immune micro environment study has been defined, histological slides are digitized to produce high-resolution images in which regions of interest are selected for the interrogation of simultaneously expressed immunomarkers (including those co-expressed by the same cell) by using an image analysis software and algorithm. Most currently available image analysis software packages use similar machine learning approaches in which tissue segmentation first defines the different components that make up the regions of interest and cell segmentation, then defines the different parameters, such as the nucleus and cytoplasm, that the software must utilize to segment single cells. Image analysis tools have driven dramatic evolution in the field of digital pathology over the past several decades and provided the data necessary for translational research and the discovery of new therapeutic targets. The next step in the growth of digital pathology is optimization and standardization of the different tasks in cancer research, including image analysis algorithm creation, to increase the amount of data generated and their accuracy in a short time as described herein. The aim of this review is to describe this process, including an image analysis algorithm creation for multiplex immunofluorescence analysis, as an essential part of the optimization and standardization of the different processes in cancer research, to increase the amount of data generated and their accuracy in a short time.

Construction and Validation of a Tumor Microenvironment-Based Scoring System to Evaluate Prognosis and Response to Immune Checkpoint Inhibitor Therapy in Lung Adenocarcinoma Patients

Background: Lung cancer is among the most dangerous malignant tumors to human health. Lung adenocarcinoma (LUAD) accounts for about 40% of all lung cancers. Accumulating evidence suggests that the tumor microenvironment (TME) is a crucial regulator of carcinogenesis and therapeutic efficacy in LUAD. However, the impact of tumor microenvironment-related signatures (TMERSs) representing the TME characteristics on the prognosis and therapeutic outcome of LUAD patients remains to be further explored. Materials and methods: Gene expression files and clinical information of 1630 LUAD samples and 275 samples with immunotherapy information from different databases such as The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and Cancer Research Institute (CRI) iAtlas were downloaded and analyzed. Three hundred tumor microenvironment-related signatures (TMERS) based on a comprehensive collection of marker genes were quantified by single sample gene set enrichment analysis (ssGSEA), and then eight significant signatures were selected to construct the tumor microenvironment-related signature score (TMERSscore) by performing Least Absolute Shrinkage and Selection Operator (LASSO)-Cox analysis. Results: In this study, we constructed a TME-based prognostic stratification model for patients with LUAD and validated it in several external datasets. Furthermore, the TMERSscore was found to be positively correlated with tumor malignancy and a high TMERSscore predicted a poor prognosis. Moreover, the TMERSscore of responders treated with Immune Checkpoint Inhibitor (ICI) therapies was significantly lower than that of non-responders, and the TMERSscore was positively correlated with the tumor immune dysfunction and exclusion (TIDE) score, implying that a low TMERSscore predicts a better response to ICI treatment and may provide independent and incremental predictive value over current biomarkers. Conclusions: Overall, we constructed a TMERSscore that can be used for LUAD patient prognosis stratification as well as ICI therapeutic efficacy evaluation, supportive results from independent external validation sets showed its robustness and effectiveness.

In vitro preliminary study on different anti-PD-1 antibody concentrations on T cells activation

Lung adenocarcinoma predominates among diagnosed nonsmall cell lung cancer subtypes in nonsmokers. The introduction of immune checkpoint inhibitors into clinical practice offered patients prolonged progression-free survival and overall survival times. However, the results demonstrate that the benefits do not apply to all patients. Nivolumab is a monoclonal antibody against the PD-1 protein expressed mainly on T lymphocytes and is widely used in cancer therapy in different settings. Tumor cells often express the PD-L1 molecule and can effectively block the action of PD-1-positive lymphocytes. A body of knowledge regarding the high expression of PD-L1 on tumor cells highlights that it does not always correlate with the effectiveness of anti-PD-1 therapy. The side effects of the therapy also constitute a significant issue. These side effects can occur at any time during anti-PD-1 treatment and lead to discontinuation and even the death of the patient. In these situations, it is possible to delay the dosage. Nevertheless, unfortunately, it is not possible to reduce the dose of anti-PD-1 antibody, which would undoubtedly minimize side effects, leaving the patient's immune system active. In our preliminary study, we analyzed the effect of different concentrations of nivolumab on the functioning of T lymphocytes. Activation and proliferation markers were investigated on T cells after being cultured with antigen-stimulated autologous dendritic cells. This process may indicate an appropriate concentration of nivolumab, which shows clinical activity with minimal side effects.

Various Subtypes of EGFR Mutations in Patients With NSCLC Define Genetic, Immunologic Diversity and Possess Different Prognostic Biomarkers

Based on data analysis of 9649 Chinese primary NSCLC patients, we calculated the exact proportion of EGFR subtypes in NSCLC and evaluated the TMB level, PD-L1 expression level and tumor immune microenvironment among different EGFR mutation subtypes. Postoperative follow-up data for 98 patients were collected and analyzed. The results showed that several uncommon EGFR mutation subtypes have a higher proportion of TMB-high or strong positive PD-L1 expression than the total EGFR mutation group. In addition, different subtypes have different characteristics related to the immune microenvironment, such as G719 mutations being associated with more CD8⁺ T cell infiltration into tumors; except for EGFR 19del, CD8⁺ T cell infiltration into tumors of other EGFR mutation subtypes were similar to that of wildtype EGFR. Moreover, follow-up results revealed that components of the immune microenvironment have prognostic value for NSCLC patients, with different prognostic biomarkers for NSCLC patients with and without EGFR mutations. These results suggest that patients with different EGFR mutations need to be treated differently. The prognosis of NSCLC patients may be assessed through components of tumor immune microenvironment, and ICIs treatment may be considered for those with some uncommon EGFR mutation subtypes.

124I-Labeled Monoclonal Antibody and Fragment for the Noninvasive Evaluation of Tumor PD-L1 Expression In Vivo

Lung cancer is a highly heterogeneous cancer and is divided broadly into small and nonsmall cell lung cancer (SCLC or NSCLC). In all NSCLC patients, it is estimated that 50%-60% are programmed cell death ligand 1 (PD-L1) positive, and anti-PD-1/PD-L1 therapies have shown their clinical application prospects in advanced NSCLC. To avoid unnecessary adverse effects and provide anti-PD-1/PD-L1 therapy to the most appropriate patient population, the PD-L1 expression in patients preparing for treatment must be evaluated accurately and in real time. In this study, we noninvasively evaluate the PD-L1 expression in an NSCLC xenograft using ¹²⁴I-labeled F(ab')₂ fragments of durvalumab (Durva) and compared it with the ¹²⁴I-labeled intact antibody in terms of the biodistribution and dosimetry. The aim is to develop a nuclide labeled molecular probe with better performance for PD-L1 immunoPET imaging. After cleaving using IdeS protease, the F(ab')₂ fragments of Durva were labeled with ¹²⁴I. The radioligand showed a high radiochemical purity (>96%) and outstanding stability. Western blot, quantitative real-time polymerase chain reaction, and flow cytometry were performed on the two selected NSCLC cell lines to measure the in vitro PD-L1 expression. The H460 cells showed a much higher PD-L1 expression than the A549 cells, both at the protein level and the mRNA level. In the following cell binding experiment and binding specificity assay, the labeled radioligand showed good affinity to high PD-L1 expression cells and could be blocked with excess unlabeled intact Durva. The results of the biodistribution and the positron emission tomography (PET) image showed that the peak tumor uptake of ¹²⁴I-Durva-F(ab')₂ was close to ¹²⁴I-Durva, but much earlier (5.29 ± 0.42% ID/g for ¹²⁴I-Durva-F(ab')₂ at 12 h vs 5.18 ± 0.73% ID/g for ¹²⁴I-Durva at 48 h). Compared with ¹²⁴I-Durva, an accelerated blood clearance was observed for ¹²⁴I-Durva-F(ab')₂. The faster blood clearance allowed for a higher tumor-to-background ratio, which was reflected on the image in contrast. The H460 tumors showed excellent contrast as early as 4 h after injection with ¹²⁴I-Durva-F(ab')₂, and for ¹²⁴I-Durva, the xenograft could not be distinguished clearly until 24 h after injection. Interestingly, ¹²⁴I-Durva-F(ab')₂ showed lower accumulations compared to other metal isotopes labeled PD-L1 antibodies in bone, liver, spleen etc., which will be beneficial for metastasis detection. Another benefit of accelerated blood clearance was a reduction in the radiation dose. According to the results of the OLINDA/EXM, the effective dose for the total body of ¹²⁴I-Durva was 4.25-times greater than that of ¹²⁴I-Durva-F(ab')₂ (186 μSv/MBq vs 43.8 μSv/MBq). All of these data indicated that ¹²⁴I-Durva-F(ab')₂ is a promising immunoPET tracer for evaluating the in vivo PD-L1 levels in an NSCLC model and is expected to be successful in future clinical application.

Non-Price-Related Determinants of Value and Access for Novel Non-small Cell Lung Cancer Treatments: A Cross-Country Review of HTA Decision Making

INTRODUCTION

Access and funding for newly approved treatments for non-small cell lung cancer (NSCLC) are often dependent on Health Technology Assessment (HTA) involving cost-effectiveness analysis. Whilst methods used by HTA agencies share many similarities, final decisions may differ. This may be the result, not just of price considerations, but also of variation in value judgements by different agencies. The aim of this study was to review international HTA evaluations to identify determinants of value and access for NSCLC treatments.

METHODS

A targeted review and analysis was undertaken of published HTAs for NSCLC across HTA agencies in six countries (Australia, Canada, England, France, Ireland and Scotland). Analysis of extracted data consisted of three stages: descriptive analysis, bivariate analysis and multivariable analysis.

RESULTS

The analysis included 163 HTAs that assessed oncological treatments for NSCLC from 2003 to 2019. The majority of HTA decisions (67.5%) were positive. However, some evidence of heterogeneity in HTA decisions and the factors informing them were identified. The most influential factors included in the multivariate model related to the HTA agency conducting the appraisal, the year of market authorisation, treatment type and the line of treatment.

CONCLUSION

Heterogenous decision-making frameworks can present a challenge to developing HTA submissions. This research contributes to understanding decision-making factors and why countries make different decisions.

Laser Immunotherapy: A Potential Treatment Modality for Keratinocyte Carcinoma

Simple Summary

In light of expanding incidences of keratinocyte carcinoma (KC) with many patients developing multiple tumors, the demand for new treatment modalities is high. With the approval of cemplimab for locally advanced and metastasizing basal cell carcinoma and squamous cell carcinoma, KC is now included as an indication for systemic immunotherapy. At present, however, systemic KC therapy remains limited by the severe side effects associated with treatment. Immunotherapy might be more broadly applied if locally administered. Localized to the skin, KCs are easily accessible to topical drugs and physical interventions such as laser. There is an increasing appreciation of lasers’ potential to activate an immune response. Further enhancement of the laser-based immune activation might be obtained by combining laser and immunotherapeutic agents, known as laser immunotherapy. In search of new treatment modalities for KC and aiming to broaden the field of KC immunotherapy, this review discusses the current literature on immune activation following both laser monotherapy and laser immunotherapy.

Abstract

The role of the immune system in cancer growth is well recognized and the development of immunotherapy represents a breakthrough in cancer treatment. Recently, the use of systemic immunotherapy was extended to keratinocyte carcinoma (KC), specifically locally advanced and metastasizing basal and squamous cell carcinoma. However, since most KC lesions are non-aggressive, systemic treatment with associated side effects is rarely justified. Conversely, topical immunotherapy with imiquimod remains restricted to premalignant and superficial lesions. Use of laser in the treatment of KC has evolved from physical tumor destruction and laser-assisted drug delivery to laser-mediated immune modulation. Evidence indicates that laser monotherapy can lead to immune cell infiltration, tumor reduction and resistance to tumor re-inoculation. Combining laser with immunotherapeutic agents, termed laser immunotherapy (LIT), may further potentiate immune activation and tumor response. Studies on LIT show not only direct anti-tumor effects but systemic adaptive immunity, illustrated by the prevention of tumor recurrence and regression in distant untreated tumors. These findings imply a therapeutic potential for both local and metastatic disease. This work provides rationales for immune-based treatment of KC and presents the current status of KC immunotherapy. Aiming to expand the field of KC immunotherapy, the review discusses the literature on immune activation following laser monotherapy and LIT.

Crizotinib efficacy in advanced non-squamous NSCLC patients with ALK or ROS1 rearrangement

In patients with advanced non-small cell lung cancer (NSCLC), comprehensive genetic diagnostics is currently carried out in order to qualify for molecularly targeted therapies and immunotherapy. The aim of the study was to assess the usefulness of the reverse transcriptase (RT-PCR) method in the diagnosis of gene rearrangements, the effectiveness of EGFR, ALK, ROS1, and PD-L1 inhibitors in first-line treatment in NSCLC patients. We enrolled 95 non-squamous NSCLC patients with known status of EGFR, ALK, ROS1, MET and RET genes and PD-L1 protein expression. We used the real time PCR, fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) and RT-PCR techniques for determination of predictive factors. In patients with ALK and ROS1 genes alteration, the median overall survival was 34 months in crizotinib treated patients and 6 months in patients who received chemotherapy (HR = 0.266, p = 0.0056). The risk of death was lower in patients treated with molecularly targeted therapies or immunotherapy compared to patients with predictive factors without personalized treatment (HR = 0.265, 95% CI 0.116-0.606) and to patient without predictive factors who received chemotherapy (HR = 0.42, 95% CI 0.162-1.09). Diagnosis of predictive factors and implementation of personalized treatment are key to prolonging the survival in advanced NSCLC patients.

PD-L1 Expression on Circulating Tumour-Derived Microvesicles as a Complementary Tool for Stratification of High-Grade Serous Ovarian Cancer Patients

BACKGROUND

Ovarian cancer (OC) has recently attracted attention for the use of PD-1/PD-L1 axis blocking agents, with durable activity reported only in a subset of patients. The most used biomarker for sensitivity to the PD-1/PD-L1 axis blockade is tumour PD-L1 status by immunohistochemistry. However, patient stratification using this method suffers from intrinsic heterogeneity of OC, likely contributing to the unsatisfactory results obtained so far. Cells communicate with each other by releasing microvesicles (MVs) that carry parental cell surface features. Thus, we hypothesised that PD-L1⁺ tumour cells (TC) and infiltrating PD-L1⁺ leukocytes should shed MVs carrying surface PD-L1 that may serve as a proxy for the whole tumour PD-L1 status.

RESULTS

We showed for the first time the presence of measurable amounts of TC- and leukocyte-derived PD-L1⁺ MVs (range: 1.4-178.8 MVs/μL and 6.2-504.8 MVs/μL, respectively) in the plasma of high-grade serous OC (HGSOC) patients (n = 63), using a sensitive flow cytometry platform. The concentration of PD-L1⁺ MVs of either origin did not associate with the PD-L1 status of TCs and leukocytes in the tumour biopsies, suggesting that the circulating PD-L1⁺ MVs also included ones from locations not selected for immunohistochemistry analysis and represented the PD-L1 status of the whole tumour mass. In this study, we also describe the serendipitous discovery of circulating PD-L1⁺ MVs of platelet origin (10.3-2409.6 MVs/μL).

CONCLUSIONS

The enumeration of circulating PD-L1⁺ MVs in HGSOC patients may provide a novel direction for assessing the tumour PD-L1 status and contribute to HGSOC patient stratification for immunotherapy interventions. The presence of circulating PD-L1⁺ MVs of platelet origin, a finding not yet reported in HGSOC patients, warrants further studies.

Immune checkpoints and immunotherapy in non-small cell lung cancer: Novel study progression, challenges and solutions

Lung cancer is the most common type of cancer with the highest mortality rate worldwide. Non-small cell lung cancer (NSCLC) accounts for ~85% of the total number of lung cancer cases. In the past two decades, immunotherapy has become a more promising treatment method than traditional treatments (surgery, radiotherapy and chemotherapy). Immunotherapy has been shown to improve the survival rate of patients and to have a superior effect when controlling lung cancer than traditional therapy. However, only a small number of patients can benefit from immunotherapy, and not all patients who qualify experience long-term benefits. In the clinic, the objective response rate of programmed cell death protein 1 treatment without the prior screening of patients is only 15-20%. Immunotherapy is associated with both opportunities and challenges for patients with NSCLC. The current challenges of immunotherapy include the lack of accurate biomarkers, inevitable resistance and insufficient understanding of immune checkpoints. In previous years, several methods for overcoming the challenges posed by immunotherapy have been proposed, but combination therapy is the most suitable choice. A large number of studies have shown that the combination of drugs can significantly improve their efficacy, compared with monotherapy, and that some therapeutic combinations have been approved by the Food and Drug Administration for the treatment of NSCLC. Traditional Chinese medicine (TCM) is a traditional medical practice in China that can play an important role in immunotherapy. Most agents used in TCM originate from plants, and have the advantages of low toxicity and multiple targets. In addition, TCM includes a unique class of drugs that can improve autoimmunity. Therefore, TCM may be a promising treatment method for all types of cancer.

Current state of knowledge on immunotherapy in ECOG PS 2 patients. A systematic review

BACKGROUND

Patients with Eastern Cooperative Oncology Group Performance Status 2 (ECOG PS 2) are not included in most randomized clinical trials and registry studies. Nevertheless, immune checkpoint inhibitors are registered in the USA and Europe regardless of the performance status. Evidence regarding the effectiveness and safety of such treatment in this cohort is sparse.

METHODS

Using PubMed (to July 2020), the relevant literature on the effect of ECOG PS 2 on the efficacy and safety of immunotherapy in patients with advanced non-small cell lung cancer (NSCLC) with ECOG PS 2 was searched.

RESULTS

A database search conducted using an international repository (PubMed) identified 191 records. Additional 3 records were identified through other sources. After pre-selection, 92 records were excluded, and 102 full-text articles were assessed for eligibility. With further exclusion of articles not meeting the inclusion criteria, 44 studies were entered into the qualitative synthesis.

CONCLUSIONS

Immunotherapy seems to be justified in PS 2 patients with NSCLC. This method of treatment has been proven to be safe and tolerable. However, outcomes in this population remain suboptimal and the impact of immunotherapy in this cohort is less dramatic. Multiple scales evaluating many factors beyond PS scores have been suggested to help stratify the PS 2 to reinforce the chance of achieving better treatment outcomes. Randomized trials are needed to determine the benefits of immune checkpoint inhibitors (ICIs) for patients with poor ECOG PS.

The Interaction Between the Microbiome and Tumors

Cancer is a significant global health problem and is characterized by a consistent increase in incidence and mortality rate. Deciphering the etiology and risk factors are essential parts of cancer research. Recently, the altered microbiome has been identified within the tumor microenvironment, tumor tissue, and even nonadjacent environments, which indicates a strong correlation between the microbiome and tumor development. However, the causation and mechanisms of this correlation remain unclear. Herein, we summarized and discussed the interaction between the microbiome and tumor progression. Firstly, the microbiome, which can be located in the tumor microenvironment, inside tumor tissues and in the nonadjacent environment, is different between cancer patients and healthy individuals. Secondly, the tumor can remodel microbial profiles by creating a more beneficial condition for the shifted microbiome. Third, the microbiome can promote tumorigenesis through a direct pathogenic process, including the establishment of an inflammatory environment and its effect on host immunity. The interactions between the microbiome and tumors can promote an understanding of the carcinogenesis and provide novel therapeutic strategies for cancers.

Viral Infection and Lung Cancer Immunotherapy

Immunotherapy with immune checkpoint inhibitors (mainly anti-PD1 and anti-PDL1 monoclonal antibodies) became a standard of care in non-small cell lung cancer (NSCLC) patients. Most of the clinical trials excluded patients with hepatitis B (HBV), hepatis C (HCV), and human immunodeficiency virus (HIV) active infection (1-10). Despite the progress in treatment of these infections, they remain an unresolved clinical problem when lung cancer immunotherapy should be initiated in an NSCLC patient. This manuscript summarizes the data from the literature concerning this subgroup of patients including the rationale for immunotherapy initiation depending on the HBV, HCV, or HIV infection status; the risk of adverse events; and the efficacy compared to non-infected patients. One of the crucial questions is how the candidates to immunotherapy should be screened for HBV, HCV, and HIV infections. The year 2020 brought the world a new but dynamic viral problem-severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2). The incorporation of known data in oncology guidelines became a burning need, and then, which group of the infected patients can be treated with immunotherapy despite the infection. Oncologists should also know if these patients should receive antiviral therapy and what are the safe combinations in these settings. We also indicate which of the adverse events should be monitored carefully during checkpoint inhibitor treatment.

Diet, Microbiome, and Cancer Immunotherapy-A Comprehensive Review

The immune system plays a key role in cancer suppression. Immunotherapy is widely used as a treatment method in patients with various types of cancer. Immune checkpoint blockade using antibodies, such as anti-PD-1, anti-PD-L1, and anti-CTLA-4, is currently gaining popularity. A systematic literature search was executed, and all available data was summarized. This review shows that specific dietary patterns (such as, e.g., animal-based, vegetarian, or Mediterranean diet) alter the gut microbiome's composition. An appropriate intestinal microbiota structure might modulate the function of human immune system, which affects the bodily anti-cancer response. This paper shows also that specific bacteria species inhabiting the gastrointestinal tract can have a beneficial influence on the efficacy of immunotherapy. Antibiotics weaken gut bacteria and worsen the immune checkpoint blockers' efficacy, whereas a faecal microbiota transplant or probiotics supplementation may help restore bacterial balance in the intestine. Other factors (like vitamins, glucose, or BMI) change the cancer treatment response, as well. This review demonstrates that there is a strong association between one's diet, gut microbiome composition, and the outcome of immunotherapy. However, further investigation on this subject is required.

Inflammatory Markers and Procalcitonin Predict the Outcome of Metastatic Non-Small-Cell-Lung-Cancer Patients Receiving PD-1/PD-L1 Immune-Checkpoint Blockade

Peripheral-immune-checkpoint blockade (P-ICB) with mAbs to PD-1 (nivolumab and pembrolizumab) or PD-L1 (atezolizumab, durvalumab, avelumab) alone or combination with chemotherapy represents a novel active treatment for mNSCLC patients. However, this therapy can be associated to immune-related adverse events (irAEs) and high cost. Therefore, finding reliable biomarkers of response and irAEs is strongly encouraged to accurately select patients who may potentially benefit from the immuno-oncological treatment. This is a retrospective multi-institutional analysis performed on ninety-five mNSCLC patients who received real-world salvage therapy with nivolumab or atezolizumab between December 2015 and April 2020. The outcome of these patients in term of PFS and OS was evaluated in comparison with different serum levels of C-reactive protein (CRP), Erythrocyte Sedimention Rate (ESR) and Procalcitonin (PCT) by performing Kaplan-Meier and Log-rank test and multivariate analysis. We found that high baseline levels of CRP, ESR, and PCT were strongly predictive of poor outcome (P <0.05) with the worse prognosis detected in those patients with a baseline levels of both ESR and PCT over the pre-established cut off (median OS recorded in patients with no marker over the cut off vs. those with just one marker over the cut off vs. those with both markers over the cut off: 40 ± 59 vs. 15.5 ± 5.5 vs. 5.5 ± 1.6 months, respectively; P <0.0001). Our results suggest the predictive value of systemic inflammation and suggest a potential role of PCT in predicting a poor outcome in mNSCLC receiving PD-1/PD-L1 blocking mAbs. This finding also suggests a potential role of subclinical bacterial infections in defining the response to PD-1/PD-L1 blocking mAbs that deserves further and more specific investigations.

A risk model developed based on tumor microenvironment predicts overall survival and associates with tumor immunity of patients with lung adenocarcinoma

Tumor microenvironment (TME) has been reported to exhibit a crucial effect in lung cancer. Therefore, this study was aimed to investigate the genes associated with TME and develop a risk score to predict the overall survival (OS) of patients with lung adenocarcinoma (LUAD) based on these genes. The immune and stromal scores were generated by the ESTIMATE algorithm for LUAD patients in The Cancer Genome Atlas (TCGA) database. Differentially expressed gene and weighted gene co-expression network analyses were used to derive immune- and stromal-related genes. The Least Absolute Shrinkage and Selection Operator (LASSO)-Cox regression was applied for further selection and the selected genes were inputted into stepwise regression to develop TME-related risk score (TMErisk) which was further validated in Gene Expression Omnibus (GEO) datasets. TMErisk-related biological phenotypes were analyzed in function enrichment, tumor immune signature, and tumor mutation signature. The patient's response to immunotherapy was inferred by the tumor immune dysfunction and exclusion (TIDE) score and immunophenoscore (IPS). According to our results, TMErisk was developed based on SERPINE1, CX3CR1, CD200R1, GBP1, IRF1, STAP1, LOX, and OR7E47P. Furthermore, high TMErisk was identified as a poor factor for OS in TCGA and GEO datasets, as well as in subgroup analysis with different gender, smoking status, age, race, anatomic site, therapies, and tumor-node-metastasis (TNM) stages. Higher TMErisk is also associated negatively with the abundance of B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and other stromal or immune cells. Several genes of the human leukocyte antigen (HLA) family and immune checkpoints were less expressed in the high-TMErisk group. Mutations of 19 genes occurred more frequently in the high-TMErisk group. These mutations may be associated with TME change and indicate patients' response to immunotherapy. According to our analyses, a lower TMErisk score may indicate better response and OS outcome of immunotherapy.

Impact of copy number variant and single nucleotide polymorphism of the programmed death-ligand 1 gene, programmed death-ligand 1 protein expression and therapy regimens on overall survival in a large group of Caucasian patients with non-small cell lung carcinoma

Anti-programmed death-1 or anti-programmed death-ligand 1 (PD-L1) blockade may be ineffective in some patients with non-small cell lung cancer (NSCLC) with high percentage of tumor cells with PD-L1 expression. In addition, immunotherapy may provide great benefits in patients without PD-L1 expression. The present study assessed PD-L1 protein expression by immunohistochemistry, copy number variation (CNV) of PD-L1 and two single nucleotide polymorphisms (SNPs), rs822335 and rs822336, in the promoter of PD-L1 by quantitative PCR in 673 patients with NSCLC. Overall survival time of patients with NSCLC depending on the assessed predictive factors (PD-L1 CNV or SNP) and the treatment methods (immunotherapy in first/second line of treatment or chemotherapy) was analyzed. The present study revealed significantly higher PD-L1 copies number in patients with ≥10% and ≥50% of tumor cells with PD-L1 expression compared to patients with lower percentage of PD-L1-positive tumor cells (P=0.02 and P=0.0002, respectively). There was a significant positive correlation (R=0.2; P=0.01) between number of PD-L1 copies and percentage of tumor cells with PD-L1 protein expression. Percentage of tumor cells with PD-L1 expression was lower in patients with TT genotype of the rs822335 polymorphism compared to those with CC genotype (P=0.03). The present study observed significantly higher risk of death in patients treated with chemotherapy compared to those treated with immunotherapy (P<0.0001; hazard ratio=2.4768; 95% confidence interval, 2.0120–3.0490). The present study demonstrated a close relationship between PD-L1 copies number, genotype of rs822335 PD-L1 polymorphism and PD-L1 protein expression on tumor cells. However, the impact of CNV and SNPs of PD-L1 on overall survival of patients with NSCLC requires further investigation.

A novel immuno-oncology algorithm measuring tumor microenvironment to predict response to immunotherapies

Immune checkpoint inhibitor (ICI) therapies can improve clinical outcomes for patients with solid tumors, but relatively few patients respond. Because ICI therapies support an adaptive immune response, patients with an active tumor microenvironment (TME) may be more likely to respond, and thus biomarkers capable of discerning an active from a quiescent TME may be useful in patient selection. We developed an algorithm optimized for genes expressed in the mesenchymal and immunomodulatory subtypes of a 101-gene triple negative breast cancer model (Ring, BMC Cancer, 2016, 16:143) as a means to capture the immunological state of the TME. We compared the outcome of the algorithm (IO score) with the 101-gene model and found 88% concordance, indicating the models are correlated but not identical, and may be measuring different TME features. We found 92.5% correlation between IO scores of matched tumor epithelial and adjacent stromal tissues, indicating the IO score is not specific to these tissues, but reflects the TME as a whole. We observed a significant difference in IO score (p = 0.0092) between samples with high tumor-infiltrating lymphocytes and samples with increased neutrophil load, demonstrating agreement between IO score and these two prognostic markers. Finally, among non-small cell lung cancer patients receiving immunotherapy, we observed a significant difference in IO score (p = 0.0035) between responders and non-responders, and a significant odds ratio (OR = 5.76, 95% CI 1.30–25.51, p = 0.021), indicating the IO score can predict patient response. The immuno-oncology algorithm may offer independent and incremental predictive value over current biomarkers in the clinic.

Cancer trigger or remedy: two faces of the human microbiome

Currently, increasing attention cancer treatment has focused on molecularly targeted therapies and more recently on immunotherapies targeting immune checkpoints. However, even such advanced treatment may be ineffective. The reasons for this are sought, inter alia, in the human microbiome. In our intestines, there are bacteria that are beneficial to us, but pathogenic microorganisms may also be present. Microbial imbalance (dysbiosis) is now perceived as one of the gateways to cancer. However, it is feasible to use bacteria and their metabolites to restore the natural, beneficial microbiome during oncological treatment. Akkermansia mucinifila, Enterococcus hirae, or Faecalibacterium prausnitzii are bacteria that exhibit this beneficial potential. Greater benefits of therapy can be observed in cancer patients enriched in these bacterial species and treated with anti-PD-1, anti-PD-L1, or anti-CTLA-4 monoclonal antibodies. In this review, we present issues related to the role of bacteria in carcinogenesis and their therapeutic potential "supporting" modern anti-cancer therapies.Key Points• Bacteria can be directly or indirectly a cancer trigger.• Bacterial metabolites regulate the pathways associated with carcinogenesis.• Intestinal bacteria activate the immune system to fight cancer.

The Multiple Potential Biomarkers for Predicting Immunotherapy Response-Finding the Needle in the Haystack

Immune checkpoint inhibitors (ICIs) are being increasingly utilised in a variety of advanced malignancies. Despite promising outcomes in certain patients, the majority will not derive benefit and are at risk of potentially serious immune-related adverse events (irAEs). The development of predictive biomarkers is therefore critical to personalise treatments and improve outcomes. A number of biomarkers have shown promising results, including from tumour (programmed cell death ligand 1 (PD-L1), tumour mutational burden (TMB), stimulator of interferon genes (STING) and apoptosis-associated speck-like protein containing a CARD (ASC)), from blood (peripheral blood mononuclear cells (PBMCs), circulating tumour DNA (ctDNA), exosomes, cytokines and metal chelators) and finally the microbiome.

Microbiome: A Supportive or a Leading Actor in Lung Cancer?

Lung cancer is still the leading cause of cancer death worldwide. Despite the major diagnostic and therapeutic innovations, the effect on mortality has been modest and the overall survival is still poor. Better understanding of the pathology of these tumors is necessary in order to develop personalized therapeutic strategies in lung cancer patients. Human microbiome has been associated with normal physiology and function, and increasing evidence points towards a key role of the microbiome in promoting the progression of lung disease. Studies have shown that although poorly understood, lung has a distinctive microbiome that may an important role in lung cancer development and progression, and interactions between microbial populations have the potential to influence disease, suggesting that microbiome can be an emerging target in cancer therapeutics. We will review mechanisms how the lung microbiota influences carcinogenesis, focusing on the bacterial dysbiosis and inflammation. Moreover, we will discuss the link between the microbiome and cancer and the consequences induced by the immune system, as the host microbiota plays an essential role in activating and modulating the immune response. We summarize current research advances in the lung microbiome and demonstrate the potential to exploit microbiome as a mechanism to prevent carcinogenesis and modulate therapeutic strategy, suggesting microbiome as a valuable approach in lung cancer patients.

Reviving up dendritic cells can run cancer immune wheel in non-small cell lung cancer: a prospective two-arm study

BACKGROUND AND AIM

Lung cancer is the number one cause of cancer-related deaths. Dendritic cells (DCs) are heterogeneous components of innate immunity that play a crucial role in the anti-tumor T cell immunity and may represent a promising approach for tumor immunotherapy. In this study, we aimed to evaluate the frequency of the two major subsets of DCs; plasmacytoid dendritic cells (pDCs) and monocytic dendritic cells (mDCs) in non-small cell lung cancer (NCSLC) and correlating them with different clinicopathologic features and survival outcomes.

PATIENTS AND METHODS

This study was a case-controlled one, included 50 patients with denovo pathologically confirmed NSCLC and 20 healthy controls of comparable age and gender. After diagnosis and staging of patients, the frequency of DCs was evaluated using flow cytometry.

RESULTS

We unveiled significantly reduced levels of pDCs (P = 0.024), and mDCs (P = 0.013) in NSCLC patients compared to controls. Furthermore, there was a significant accumulation of pDCs in non-metastatic patients compared to metastatic ones (P < 0.0001), while there was no significant (P = 0.6) differences in mDCs, and mDCs/pDCs ratio (P = 0.9). There was a Significant negative correlation (r = - 0.3, P = 0.04) between OS and mDCs. On the other hand, there was a significantly higher OS with pDCs ≥ 0.82 compared to patients with pDCs < 0.82, log rank Ch² = 12.128, P < 0.0001.

CONCLUSION

Despite the controversy about the prognostic role of pDCs not only in NSCLC but also in other solid tumors, our study sheds light on the possible prognostic impact of pDCs and mDCs on treatment outcomes of NSCLC patients.

A Novel Epitope Quality-Based Immune Escape Mechanism Reveals Patient's Suitability for Immune Checkpoint Inhibition

Background

Immune checkpoint inhibition, especially the blockade of PD-1 and PD-L1, has become one of the most thriving therapeutic approaches in modern oncology. Immune evasion caused by altered tumor epitope processing (so-called processing escapes) may be one way to explain immune checkpoint inhibition therapy failure. In the present study, we aim to demonstrate the effects of processing escapes on immunotherapy outcome in NSCLC patients.

Patients and Methods

Whole exome sequencing data of 400 NSCLC patients (AdC and SCC) were extracted from the TCGA database. The ICB cohort was composed of primary tumor probes from 48 NSCLC patients treated with nivolumab. Mutations were identified by targeted amplicon-based sequencing including hotspots and whole exomes of 22 genes. The effect of mutations on proteasomal processing was evaluated by deep learning methods previously trained on 1260 known MHC-I ligands. Cox regression modelling was used to determine the influence on overall survival.

Results

In the TCGA cohort, processing escapes were associated with decreased overall survival (p= 0.0140). In the ICB cohort, patients showing processing escapes in combination with high levels of PD-L1 (n=8/48) also showed significantly decreased overall survival, independently of mutational load or PD-L1 status.

Conclusion

The concept of altered epitope processing may help to understand immunotherapy failure. Especially when combined with PD-L1 status, this method can be used as a biomarker to identify patients not suitable for immunotherapy.

Clinical Significance of Program Death Ligand-1 and Indoleamine-2,3-Dioxygenase Expression in Colorectal Carcinoma

Colorectal cancer is a heterogenous disease with striking biological diversity. Colorectal carcinoma (CRC) is one of the most common malignancies, accounting for over 9% of all cancers worldwide. To put it in perspective, 5% of people will develop CRC in their lifetime. Biomarkers specific to a particular cancer type can assist in the evaluation of survival probability and help clinicians assess treatment modalities, an example being programmed death ligand-1 (PD-L1). With regards to PD-L1, this is the first study to evaluate the SP-142 antibody clone in CRC. The Ventana PD-L1 (SP-142) assay for PD-L1 expression identifies patients who may benefit from treatment with atezolizumab. SP-142 was chosen as large stage 3 clinical trials are being undertaken with atezolizumab in CRC. Indoleamine 2,3-dioxygenase (IDO-1) was also chosen as there are several ongoing trials for Epacadostat, the best-in-class oral IDO-1 enzyme inhibitor, in many solid tumors. For solid tumors, IDO-1-based immune escape has the potential to inhibit monotherapeutic efficacy of PD-L1-based therapeutics. In this study, a total of 223 cases of CRC were retrospectively reviewed and clinicopathologic data were analyzed in relation to PD-L1 and IDO-1 protein expression. Moreover, tumor-infiltrating lymphocytes, mismatch repair deficiency, high mitotic index, and worse survival outcomes were found in cohorts with significant PD-L1 and IDO-1 expression. Both PD-L1 and IDO-1 are actionable biomarkers, with potential therapeutic implications in CRC. Our findings support the theoretical foundation for targeting PD-L1 and IDO-1 in CRC, which now needs verification in well-designed robust clinical trials.

PD-L1 as a prognostic biomarker in surgically resectable non-small cell lung cancer: a meta-analysis

Background

PD-L1 tumor expression has been associated with poor prognosis in a variety of solid tumors, including lung cancer, and represents a validated target for immune checkpoint inhibition in advanced malignances. It remains unknown, however, if PD-L1 can be used to predict survival in early stage, surgically treated cancers. This meta-analysis compares PD-L1 tumor expression and long term survival after surgical resection in early non-small cell lung cancer (NSCLC).

Methods

PubMed was searched to identify eligible studies that compared survival of surgically resected stage I–III NSCLC patients according to PD-L1 tumor expression. Included studies were grouped according to measurement criteria of PD-L1 expression: 1%, 5%, 50% cutoffs or H-score. Meta-analysis was performed using a linear mixed-effects model to determine overall survival (OS). I² was used as a measure of heterogeneity.

Results

There were 40 eligible studies, including 10,380 patients. Regardless of cut-off used, higher PD-L1 tumor expression was associated with worse OS [hazard ratio (HR)_1%: 1.59, 95% confidence interval (CI), 1.17–2.17; HR_5%: 1.44, 95% CI, 1.03–2.00; HR_50%: 1.52, 95% CI, 1.02–2.25, HR_H-score: 1.34, 95% CI, 1.04–1.73]. Study heterogeneity was low and not statistically significant under all PD-L1 cutoffs.

Conclusions

PD-L1 expression is consistently associated with worse survival, regardless of how it is quantified. In addition to acting as a prognostic biomarker, PD-L1 may also be used in future as a predictive biomarker for patients most likely to benefit from adjuvant immunotherapy.

Immunotherapy Alone or in Combination with Chemotherapy as First-Line Treatment of Non-Small Cell Lung Cancer

OPINION STATEMENT

Immune checkpoint inhibitors (ICIs) have revolutionized the management of metastatic and selected cases of unresectable advanced non-small cell lung cancer (NSCLC). Importantly for patients, this implies that in the absence of a targetable oncogenic driver [especially epidermal growth factor receptor (EGFR) gene mutations and anaplastic lymphoma kinase (ALK) gene rearrangements] and in the presence of high programmed death-ligand 1 (PD-L1) expression (≥ 50%), they are eligible for mono-therapy with pembrolizumab thereby avoiding chemotherapy as the first line of treatment. This mono-immunotherapy approach for high PD-L1 metastatic NSCLC is associated with improved overall survival (OS) and radiological responses (RR) with lesser toxicity as compared with conventional platinum doublet chemotherapy for both non-squamous and squamous histological types.However, majority of NSCLC patients either have no or low expression of PD-L1 (< 50%) and such patients derive greater benefit from a combination of PD-1/PD-L1 ICIs with platinum doublet chemotherapy as compared with chemotherapy alone. Again, benefits are seen for both OS and RRs. However, combining immunotherapy with chemotherapy, in general, does lead to higher toxicity than those seen with either of the two alone.Additionally, for non-squamous NSCLC patients, clinicians should not initiate ICI treatment till the results of common targetable genetic alterations like EGFR mutation, ALK, and ROS1 gene rearrangement testing are known (preferably on broad next generation sequencing) and are negative (even if results of PD-L1 testing are available)-as targeted therapies remain the cornerstone of treatment for patients harboring these oncogenic drivers.It is worth mentioning that PD-1 and PD-L1 ICIs are very expensive, and their usage is associated with occurrence of immune-related adverse events (irAEs) which occasionally can be severe. Hence, it is important to discuss efficacy, toxicity, and cost-related to ICI treatment with each and every patient at diagnosis in order to help them decide if they are willing to go ahead with this form of therapy either singly (for high PD-L1 expressors) or in combination with chemotherapy (for others).

Aptamers in Non-Small Cell Lung Cancer Treatment

Aptamers are short, single-stranded oligonucleotides which are capable of specifically binding to single molecules and cellular structures. Aptamers are also known as “chemical antibodies”. Compared to monoclonal antibodies, they are characterized by higher reaction specificity, lower molecular weight, lower production costs, and lower variability in the production stage. Aptamer research has been extended during the past twenty years, but only Macugen^® has been accepted by the Food and Drug Administration (FDA) to date, and few aptamers have been examined in clinical trials. In vitro studies with aptamers have shown that they may take part in the regulation of cancer progression, angiogenesis, and metastasis processes. In this article, we focus on the potential use of aptamers in non-small cell lung cancer treatment.

Immune Checkpoint Inhibitors in Lung Cancer: Role of Biomarkers and Combination Therapies

Lung cancer is the leading cause of cancer-related death worldwide, with a poor prognosis. Despite aggressive treatment, progression-free survival (PFS) and overall survival are limited. Recently, various kinds of immune checkpoint inhibitors (ICIs) have emerged for several cancers, targeting PD1, PDL1, and CTLA-4. ICIs have made a significant breakthrough in cancer and revolutionized the management of cancer including lung cancer. However, there are a lot of controversies regarding which group of patients is most suitable to be treated with ICIs in terms of monotherapy, combination, and predictive biomarkers. We reviewed various kinds of studies, such as meta-analysis, randomized control trials, multi-center cohort studies, and case-control studies from PubMed written in English from the last five years. ICIs have significant benefits in the overall survival compared with traditional chemotherapy. Patients with a higher level of PDL1 expression and high tumor mutational burden (TMB) have a higher response rate, and those with EGFR-/ALK- were better than those with EGFR+/ALK+. The patient who responded to immunotherapy completely can still maintain the efficacy after two years of treatment. Neoadjuvant immunotherapy in patients with resectable non-small cell lung cancer resulted in a 45% major pathology response (MPR) and 40% downstaging. Combined therapy (ICIs + chemotherapy) was better than chemotherapy alone, irrespective of PD-L1 expression. A combination of ICIs such as CTLA-4 and PD-1/PD-L1 improved PFS as well. Radiochemotherapy ahead of ICIs is promising as well. However, ICIs combined with EGFR/ALK-TKI (tyrosine kinase inhibitor) are not suggested for the time being. PDL1 expression, TMB, and EGFR/ALK mutations are promising predictive biomarkers. Gut microbiota, galectin-3, and intensity of CD8 cell infiltration are other potential predictive biomarkers. These are very important in the future management of lung cancers as they can prevent unnecessary toxicities and cost of treatment.

BTK Has Potential to Be a Prognostic Factor for Lung Adenocarcinoma and an Indicator for Tumor Microenvironment Remodeling: A Study Based on TCGA Data Mining

Tumor microenvironment (TME) plays a crucial role in the initiation and progression of lung adenocarcinoma (LUAD); however, there is still a challenge in understanding the dynamic modulation of the immune and stromal components in TME. In the presented study, we applied CIBERSORT and ESTIMATE computational methods to calculate the proportion of tumor-infiltrating immune cell (TIC) and the amount of immune and stromal components in 551 LUAD cases from The Cancer Genome Atlas (TCGA) database. The differentially expressed genes (DEGs) were analyzed by COX regression analysis and protein–protein interaction (PPI) network construction. Then, Bruton tyrosine kinase (BTK) was determined as a predictive factor by the intersection analysis of univariate COX and PPI. Further analysis revealed that BTK expression was negatively correlated with the clinical pathologic characteristics (clinical stage, distant metastasis) and positively correlated with the survival of LUAD patients. Gene Set Enrichment Analysis (GSEA) showed that the genes in the high-expression BTK group were mainly enriched in immune-related activities. In the low-expression BTK group, the genes were enriched in metabolic pathways. CIBERSORT analysis for the proportion of TICs revealed that B-cell memory and CD8+ T cells were positively correlated with BTK expression, suggesting that BTK might be responsible for the preservation of immune-dominant status for TME. Thus, the levels of BTK might be useful for outlining the prognosis of LUAD patients and especially be a clue that the status of TME transition from immune-dominant to metabolic activity, which offered an extra insight for therapeutics of LUAD.

Detection of PD-L1 Expression and Its Clinical Significance in Circulating Tumor Cells from Patients with Non-Small-Cell Lung Cancer

Background

The expression of programmed cell death ligand 1(PD-L1) is related to the efficacy of immune checkpoint inhibitors on patients with non-small cell lung cancer (NSCLC), but tumor tissue (TT) samples are difficult to obtain, and initial TT samples are difficult to reflect the spatial-temporal heterogeneity. Therefore, we explored the feasibility of separating circulating tumor cells (CTCs) and detecting PD-L1 expression on CTCs.

Patients and Methods

Peripheral blood specimens were sampled from 66 NSCLC patients, and CTCs were separated by membrane filtration based on size. For 59 patients with paired TT specimens, the expression of PD-L1 in their CTCs and TTs was determined using the immunohistochemistry and immunocytochemistry based on 28–8 antibody, respectively. The PD-L1 expression in TTs was set as a gold standard for calculation of sensitivity, specificity, consistency, positive predictive value (PPV), and negative predictive value (NPV), and the Cohen kappa coefficient for CTCs and paired TTs was calculated. In addition, the T-test, Chi-square test, and Mann–Whitney U-test were adopted to analyze the correlation of clinical pathological features and prognosis with PD-L1 expression.

Results

Sensitivity, specificity, concordance, PPV and NPV of detecting PD-L1 in CTCs of the 41 initial treated patients were 88.89%, 73.91%, 80%, 72.73% and 89.47%, respectively, and the Cohen kappa coefficient of CTC and paired TTs was 0.613. The univariate analysis of survival showed that the progression-free survival time of initial treated patients with positive PD-L1 expression was shorter than that of those with negative PD-L1 expression in CTCs or TTs (P>0.05), and the positive PD-L1 expression in CTCs or TTs had nothing to do with age, sex, smoking status, histological type, and stage (P > 0.05).

Conclusion

The study confirms the feasibility of CTC PD-L1 detection in peripheral blood and lays a foundation for exploring real-time and individualized immunotherapy molecular biomarkers.

A 5-Gene Signature Is Closely Related to Tumor Immune Microenvironment and Predicts the Prognosis of Patients with Non-Small Cell Lung Cancer

Purpose

Establishing prognostic gene signature to predict clinical outcomes and guide individualized adjuvant therapy is necessary. Here, we aim to establish the prognostic efficacy of a gene signature that is closely related to tumor immune microenvironment (TIME).

Methods and Results

There are 13,035 gene expression profiles from 130 tumor samples of the non-small cell lung cancer (NSCLC) in the data set GSE103584. A 5-gene signature was identified by using univariate survival analysis and Least Absolute Shrinkage and Selection Operator (LASSO) to build risk models. Then, we used the CIBERSORT method to quantify the relative levels of different immune cell types in complex gene expression mixtures. It was found that the ratio of dendritic cells (DCs) activated and mast cells (MCs) resting in the low-risk group was higher than that in the high-risk group, and the difference was statistically significant (P < 0.001 and P=0.03). Pathway enrichment results which were obtained by performing Gene Set Variation Analysis (GSVA) showed that the high-risk group identified by the 5-gene signature had metastatic-related gene expression, resulting in lower survival rates. Kaplan–Meier survival results showed that patients of the high-risk group had shorter disease-free survival (DFS) and overall survival (OS) than those of the low-risk group in the training set (P=0.0012 and P < 0.001). The sensitivity and specificity of the gene signature were better and more sensitive to prognosis than TNM (tumor/lymph node/metastasis) staging, in spite of being not statistically significant (P=0.154). Furthermore, Kaplan–Meier survival showed that patients of the high-risk group had shorter OS and PFS than those of the low-risk group (P=0.0035, P < 0.001, and P < 0.001) in the validating set (GSE31210, GSE41271, and TCGA). At last, univariate and multivariate Cox proportional hazard regression analyses were used to evaluate independent prognostic factors associated with survival, and the gene signature, lymphovascular invasion, pleural invasion, chemotherapy, and radiation were employed as covariates. The 5-gene signature was identified as an independent predictor of patient survival in the presence of clinical parameters in univariate and multivariate analyses (P < 0.001) (hazard ratio (HR): 3.93, 95% confidence interval CI (2.17–7.1), P=0.001, (HR) 5.18, 95% CI (2.6995–9.945), P < 0.001), respectively. Our 5-gene signature was also related to EGFR mutations (P=0.0111), and EGFR mutations were mainly enriched in low-risk group, indicating that EGFR mutations affect the survival rate of patients.

Conclusion

The 5-gene signature is a powerful and independent predictor that could predict the prognosis of NSCLC patients. In addition, our gene signature is correlated with TIME parameters, such as DCs activated and MCs resting. Our findings suggest that the 5-gene signature closely related to TIME could predict the prognosis of NSCLC patients and provide some reference for immunotherapy.

Preventive CTLA-4-Ig Treatment Reduces Hepatic Egg Load and Hepatic Fibrosis in Schistosoma mansoni-Infected Mice

Background

Hepatic fibrosis and granuloma formation as a consequence of tissue entrapped eggs produced by female schistosomes characterize the pathology of Schistosoma mansoni infection. We have previously shown that single-sex infection with female schistosomes mitigates hepatic fibrosis after secondary infection. This was associated with an increased expression of cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), known as a negative regulator of T cell activation. Based on these findings, we hypothesized that administration of agonistic CTLA-4-Ig (Belatacept) is capable to prevent and/or treat hepatic fibrosis during schistosomiasis.

Methods

Mice were infected with 50 S. mansoni cercariae and CTLA-4-Ig, or appropriated control-Ig was administered for 4 weeks. Preventive treatment started 4 weeks after infection, before onset of egg production, and therapeutic treatment started 8 weeks after infection when hepatic fibrosis was already established.

Results

When given early after infection, livers of CTLA-4-Ig-treated mice showed significantly reduced collagen deposition and decreased expression of profibrotic genes in comparison to controls. In addition, administration of CTLA-4-Ig suppressed the inflammatory T cell response in infected mice. If therapy was started at a later time point when fibrogenesis was initiated, CTLA-4-Ig had no impact on hepatic fibrosis.

Conclusion

We could demonstrate that an early preventive administration of CTLA-4-Ig suppresses effector T cell function and therefore ameliorates liver fibrosis. CTLA-4-Ig administration after onset of egg production fails to treat hepatic fibrosis.

In Vitro Assessment of Putative PD-1/PD-L1 Inhibitors: Suggestions of an Alternative Mode of Action

The programmed cell death protein 1 (PD-1) signaling axis is among the most important therapeutic targets in modern oncology. Aurigene Discovery Technologies Ltd. (Aurigene) has patented a series of peptidomimetic small molecules derived from the PD-1 protein sequence for use in targeting the interaction between PD-1 and its ligand, PD-L1. We evaluated three of Aurigene's most potent compounds in SPR binding assays. Our results showed that these compounds-each of which is known to be potently effective in a splenocyte recovery assay-do not directly inhibit the PD-1/PD-L1 interaction nor do they appear to bind to either of the constituent proteins, indicating that another mechanism is at play. As a result of these studies and upon consideration of structural features within the PD-1/PD-L1 complex, we hypothesize that the Aurigene molecules may interact with a currently unknown protein capable of regulating the PD-1 axis.

PD-L1/PD-1 Expression in Endometrial Clear Cell Carcinoma: A Potential Surrogate Marker for Clinical Trials

Background. Endometrial clear cell carcinoma (ECCC) represents a rare subtype of endometrial cancer. Recently, immunotherapeutic drugs targeting programmed cell death protein 1 (PD-1)/programmed death ligand-1 (PD-L1) was associated with improved survival in several types of cancer (especially in patients with mismatch-repair (MMR)-deficient status). The aim of this study is to evaluate the correlation between the PD-L1/PD-1 axis and clinical and pathological features in strictly defined ECCC diagnosed at our institution. Design. Review of ECCC (diagnosed in the period of 2000 to 2017) identified 23 cases (n = 23) in our institution. The cases were reviewed by 2 gynecological pathologists. Estrogen receptor, progesterone receptor, napsin A, p16, and p53 were also performed so that only pure CCC cases were included. PD-L1 (SP142), PD-1, and MMR antibodies were performed. PD-L1 and PD-1 were scored in both the tumor and the peritumoral lymphocyte infiltration. Clinical and pathological features were recorded to correlate with the expression of the 2 markers. Results. Among the 23 cases, 20 cases were qualified for pure CCC by histology and immunohistochemistry patterns. Regarding PD-1 expression, 6/20 (30%) patients had positive expression in peritumoral lymphocyte infiltration. While 3/20 (15%) cases had PD-L1 either tumoral or peritumoral lymphocytes expression. Loss of MMR expression was present in 1 (5%) of 20 patients. PD-1 and/or PD-L1 expression cases tended to have deeper myometrial invasion and higher stage at presentation. Conclusions. Our results are suggestive of the roles of both PD-1 and PD-L1 in ECCCs as useful therapeutic biomarkers for immunotherapy.