Predictive value of serum protein levels in patients with advanced non-small cell lung cancer treated with nivolumab

Biomarkers associated with immune-related adverse events induced by immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) constitute a pivotal class of immunotherapeutic drugs in cancer treatment. However, their widespread clinical application has led to a notable surge in immune-related adverse events (irAEs), significantly affecting the efficacy and survival rates of patients undergoing ICI therapy. While conventional hematological and imaging tests are adept at detecting organ-specific toxicities, distinguishing adverse reactions from those induced by viruses, bacteria, or immune diseases remains a formidable challenge. Consequently, there exists an urgent imperative for reliable biomarkers capable of accurately predicting or diagnosing irAEs. Thus, a thorough review of existing studies on irAEs biomarkers is indispensable. Our review commences by providing a succinct overview of major irAEs, followed by a comprehensive summary of irAEs biomarkers across various dimensions. Furthermore, we delve into innovative methodologies such as machine learning, single-cell RNA sequencing, multiomics analysis, and gut microbiota profiling to identify novel, robust biomarkers that can facilitate precise irAEs diagnosis or prediction. Lastly, this review furnishes a concise exposition of irAEs mechanisms to augment understanding of irAEs prediction, diagnosis, and treatment strategies.

IFNγ-Induced Bcl3, PD-L1 and IL-8 Signaling in Ovarian Cancer: Mechanisms and Clinical Significance

IFNγ, a pleiotropic cytokine produced not only by activated lymphocytes but also in response to cancer immunotherapies, has both antitumor and tumor-promoting functions. In ovarian cancer (OC) cells, the tumor-promoting functions of IFNγ are mediated by IFNγ-induced expression of Bcl3, PD-L1 and IL-8/CXCL8, which have long been known to have critical cellular functions as a proto-oncogene, an immune checkpoint ligand and a chemoattractant, respectively. However, overwhelming evidence has demonstrated that these three genes have tumor-promoting roles far beyond their originally identified functions. These tumor-promoting mechanisms include increased cancer cell proliferation, invasion, angiogenesis, metastasis, resistance to chemotherapy and immune escape. Recent studies have shown that IFNγ-induced Bcl3, PD-L1 and IL-8 expression is regulated by the same JAK1/STAT1 signaling pathway: IFNγ induces the expression of Bcl3, which then promotes the expression of PD-L1 and IL-8 in OC cells, resulting in their increased proliferation and migration. In this review, we summarize the recent findings on how IFNγ affects the tumor microenvironment and promotes tumor progression, with a special focus on ovarian cancer and on Bcl3, PD-L1 and IL-8/CXCL8 signaling. We also discuss promising novel combinatorial strategies in clinical trials targeting Bcl3, PD-L1 and IL-8 to increase the effectiveness of cancer immunotherapies.

Proteomic and metabolomic profiling of plasma predicts immune-related adverse events in older patients with advanced non-small cell lung cancer

The clinical success of immune checkpoint inhibitors is compromised by the fact of immune-related adverse events (irAEs), especially for older patients. To identify predictive biomarkers for older patients with irAEs, we used multiplex immunoassay and flow cytometry and liquid chromatography-tandem mass spectrometry to test immune factors and plasma protein and metabolites levels in non-small cell lung cancer (NSCLC) patients. The results showed that older patients with irAEs displayed lower CD28, CD4+ T cell, and B cell and higher interleukin (IL)-10 and CCL2 levels at baseline. Besides, lower aldolase, fructose-bisphosphate B (ALDOB), higher ST6GAL1, and lower lactate/pyruvate ratio at baseline were found in older patients with irAEs. Based on metabolomic markers, predictive models were developed to distinguish patients with grade 2-4 irAEs from grade 0-1 (Area under curve, AUC = 0.831) and to distinguish patients with grade 3-4 irAEs from grade 2 (AUC = 1). Our results confirmed the predictive value of plasma metabolites for irAEs in older patients with NSCLC.

Circulating biomarkers as predictors of response to immune checkpoint inhibitors in NSCLC: Are we on the right path?

Immune checkpoints inhibitors (ICIs) have markedly improved the therapeutic management of advanced NSCLC and, more recently, they have demonstrated efficacy also in the early-stage disease. Despite better survival outcomes with ICIs compared to standard chemotherapy, a large proportion of patients can derive limited clinical benefit from these agents. So far, few predictive biomarkers, including the programmed death-ligand 1 (PD-L1), have been introduced in clinical practice. Therefore, there is an urgent need to identify novel biomarkers to select patients for immunotherapy, to improve efficacy and avoid unnecessary toxicity. A deeper understanding of the mechanisms involved in antitumor immunity and advances in the field of liquid biopsy have led to the identification of a wide range of circulating biomarkers that could potentially predict response to immunotherapy. Herein, we provide an updated overview of these circulating biomarkers, focusing on emerging data from clinical studies and describing modern technologies used for their detection.

Biomarkers for immune-related adverse events in cancer patients treated with immune checkpoint inhibitors

Although immune checkpoint inhibitors have greatly improved cancer therapy, they also cause immune-related adverse events, including a wide range of inflammatory side effects resulting from excessive immune activation. Types of immune-related adverse events are diverse and can occur in almost any organ, with different frequencies and severities. Furthermore, immune-related adverse events may occur within the first few weeks after treatment or even several months after treatment discontinuation. Predictive biomarkers include blood cell counts and cell surface markers, serum proteins, autoantibodies, cytokines/chemokines, germline genetic variations and gene expression profiles, human leukocyte antigen genotype, microRNAs and the gut microbiome. Given the inconsistencies in research results and limited practical utility, there is to date no established biomarker that can be used in routine clinical practice, and additional investigations are essential to demonstrate efficacy and subsequently facilitate integration into routine clinical use.

Bone marrow adipocytes and lung cancer bone metastasis: unraveling the role of adipokines in the tumor microenvironment

Bone is a common site of metastasis for lung cancer. The "seed and soil" hypothesis suggests that the bone marrow microenvironment ("soil") may provide a conducive survival environment for metastasizing tumor cells ("seeds"). The bone marrow microenvironment, comprising a complex array of cells, includes bone marrow adipocytes (BMAs), which constitute about 70% of the adult bone marrow volume and may play a significant role in tumor bone metastasis. BMAs can directly provide energy for tumor cells, promoting their proliferation and migration. Furthermore, BMAs participate in the tumor microenvironment's osteogenesis regulation, osteoclast(OC) regulation, and immune response through the secretion of adipokines, cytokines, and inflammatory factors. However, the precise mechanisms of BMAs in lung cancer bone metastasis remain largely unclear. This review primarily explores the role of BMAs and their secreted adipokines (leptin, adiponectin, Nesfatin-1, Resistin, chemerin, visfatin) in lung cancer bone metastasis, aiming to provide new insights into the mechanisms and clinical treatment of lung cancer bone metastasis.

An immunosuppressive subtype of senescent tumor cells predicted worse immunotherapy response in lung adenocarcinoma

Senescent tumor cells (STCs) can induce immunosuppression, promoting tumor progression and therapy resistance. However, the specific characteristics of immunosuppressive STC have not been thoroughly investigated. This study aimed to characterize and elucidate the immunosuppressive phenotype of STC in lung adenocarcinoma by employing single-cell and bulk transcriptomics, as well as serum proteomics profiling. We identified senescence-related genes specific to tumors and identified Cluster10 of STC as the immunomodulatory subtype. Cluster10 exhibited a distinct secretome dominated by cytokines such as CXCL1, CXCL2, and CXCL8 and showed activation of transcription factors associated with cytokine secretion, including NFKB1, RELA, and STAT3. Notably, Cluster10 demonstrated the highest degree of intercellular communication among all cell types, with interactions as LGALS9-TIM3 and MIF-CD74. Furthermore, Cluster10 showed significant associations with poor prognosis and diminished response to immunotherapy. Analysis of serum proteomics data from our in-house cohort identified CXCL8 as a potential marker for predicting immunotherapeutic outcomes.

Predictive Biomarkers for Checkpoint Inhibitor Immune-Related Adverse Events

Immune-checkpoint inhibitors (ICIs) are antagonists of inhibitory receptors in the immune system, such as the cytotoxic T-lymphocyte-associated antigen-4, the programmed cell death protein-1 and its ligand PD-L1, and they are increasingly used in cancer treatment. By blocking certain suppressive pathways, ICIs promote T-cell activation and antitumor activity but may induce so-called immune-related adverse events (irAEs), which mimic traditional autoimmune disorders. With the approval of more ICIs, irAE prediction has become a key factor in improving patient survival and quality of life. Several biomarkers have been described as potential irAE predictors, some of them are already available for clinical use and others are under development; examples include circulating blood cell counts and ratios, T-cell expansion and diversification, cytokines, autoantibodies and autoantigens, serum and other biological fluid proteins, human leucocyte antigen genotypes, genetic variations and gene profiles, microRNAs, and the gastrointestinal microbiome. Nevertheless, it is difficult to generalize the application of irAE biomarkers based on the current evidence because most studies have been retrospective, time-limited and restricted to a specific type of cancer, irAE or ICI. Long-term prospective cohorts and real-life studies are needed to assess the predictive capacity of different potential irAE biomarkers, regardless of the ICI type, organ involved or cancer site.

Monocyte chemoattractant protein 1 as a potential biomarker for immune checkpoint inhibitor-associated neurotoxicity

BACKGROUND

Oncological patients can benefit substantially from treatment with immune checkpoint inhibitors (ICI). However, there is a growing awareness of immune-related adverse events (irAE). Especially ICI-mediated neurological adverse events (nAE(+)), are tough to diagnose and biomarkers to identify patients at risk are missing.

METHODS

A prospective register with prespecified examinations was established for ICI treated patients in December 2019. At the time of data cut-off, 110 patients were enrolled and completed the clinical protocol. Herein, cytokines and serum neurofilament light chain (sNFL) from 21 patients were analyzed.

RESULTS

nAE of any grade were observed in 31% of the patients (n = 34/110). In nAE(+) patients a significant increase in sNFL concentrations over time was observed. Patients with higher-grade nAE had significantly elevated serum-concentrations of monocyte chemoattractant protein 1 (MCP-1) and brain-derived neurotrophic factor (BDNF) at baseline compared to individuals without any nAE (p < 0.01 and p < 0.05).

CONCLUSION

Here, we identified nAE to occur more frequently than previously reported. Increase of sNFL during nAE confirms the clinical diagnosis of neurotoxicity and might be a suitable marker for neuronal damage associated with ICI therapy. Furthermore, MCP-1 and BDNF are potentially the first clinical-class nAE predictors for patients under ICI therapy.

Immune checkpoint inhibitor-associated toxicity in advanced non-small cell lung cancer: An updated understanding of risk factors

Immune checkpoint inhibitors (ICIs), such as programmed death-1 (PD-1), programmed death-ligand 1 (PD-L1), cytotoxic T lymphocyte antigen 4 (CTLA-4) antibodies, etc, have revolutionized cancer treatment strategies, including non-small cell lung cancer (NSCLC). While these immunotherapy agents have achieved durable clinical benefits in a subset of NSCLC patients, they bring in a variety of immune-related adverse events (irAEs), which involve cardiac, pulmonary, gastrointestinal, endocrine and dermatologic system damage, ranging from mild to life-threatening. Thus, there is an urgent need to better understand the occurrence of irAEs and predict patients who are susceptible to those toxicities. Herein, we provide a comprehensive review of what is updated about the clinical manifestations, mechanisms, predictive biomarkers and management of ICI-associated toxicity in NSCLC. In addition, this review also provides perspective directions for future research of NSCLC-related irAEs.

Innate immune function during antineoplastic treatment is associated with 12-months survival in non-small cell lung cancer

Introduction

The immune system has proven to be a key player in the progression as well as containment of cancer with new treatment strategies based on immunotherapy targeting this interaction. Assessing immune function could reveal critical information about the immune response to therapeutic interventions, revealing predictive biomarkers for tailored care and precision medicine.

Methods

We investigated immune function in 37 patients with inoperable non-small cell lung cancer (NSCLC) undergoing treatment with PD-L1 immune checkpoint inhibitor (ICI), chemotherapy (CT) or chemo-radiotherapy (CT/RT). Blood samples before (day 0) and during therapy (day 7, 21 and 80) were investigated by a standardized immunoassay, TruCulture®.

Results

Outcomes revealed a developing innate immune response induced by both immunotherapy and chemotherapy. NSCLC-patients displayed evidence of chronic innate immune activation and exhaustion prior to treatment. This pattern was particularly pronounced during treatment in patients dying within 12-months follow-up. Compared to treatment with CT, ICI demonstrated a higher ex vivo-stimulated release of proinflammatory cytokines.

Discussion

These preliminary findings may pave the way for tailored treatment and immune-monitoring.

The role of immune profile in predicting outcomes in cancer patients treated with immunotherapy

Background

Despite the efficacy of immunotherapy, only a small percentage of patients achieves a long-term benefit in terms of overall survival. The aim of this study was to define an immune profile predicting the response to immune checkpoint inhibitors (ICIs).

Methods

Patients with advanced solid tumors, who underwent ICI treatment were enrolled in this prospective study. Blood samples were collected at the baseline. Thirteen soluble immune checkpoints, 3 soluble adhesion molecules, 5 chemokines and 11 cytokines were analyzed. The results were associated with oncological outcomes.

Results

Regardless of tumor type, patients with values of sTIM3, IFNα, IFNγ, IL1β, IL1α, IL12p70, MIP1β, IL13, sCD28, sGITR, sPDL1, IL10 and TNFα below the median had longer overall survival (p<0.05). By using cluster analysis and grouping the patients according to the trend of the molecules, two clusters were found. Cluster A had a significantly higher mean progression free survival (Cluster A=11.9 months vs Cluster B=3.5 months, p<0.01), a higher percentage of disease stability (Cluster A=34.5% vs. Cluster B=0%, p<0.05) and a lower percentage of disease progression (Cluster A=55.2% vs. Cluster B = 94.4%, p=0.04).

Conclusion

The combined evaluation of soluble molecules, rather than a single circulating factor, may be more suitable to represent the fitness of the immune system status in each patient and could allow to identify two different prognostic and predictive outcome profiles.

Immune checkpoint inhibitor related nephrotoxicity: Advances in clinicopathologic features, noninvasive approaches, and therapeutic strategy and rechallenge

Immune checkpoint inhibitors (ICIs) are used increasingly to treat more than 17 cancers and have shown promising therapeutic results. However, ICI use can result in a variety of immune-related adverse events (IRAEs) which can occur in any organ, including the kidneys. Acute kidney injury (AKI) is the most common nephrotoxicity, classically related to acute interstitial nephritis. Much more diverse patterns and presentations of ICI-related kidney injury can occur, and have implications for diagnostic and therapeutic management approaches. In this review, we summarize the recently approved ICIs for cancer, the incidence and risk factors for nephrotoxicity, our current understanding of the pathophysiological mechanisms and the key clinicopathological features of ICI-related AKI, and therapeutic strategies. We also explore important knowledge that require further investigation, such as the risks/benefits of ICI rechallenge in patients who recover from an episode of ICI-related AKI, and the application of liquid biopsy and microbiome to identify noninvasive biomarkers to diagnose and predict kidney injury and guide ICI therapy.

Neutrophils: Musketeers against immunotherapy

Neutrophils, the most copious leukocytes in human blood, play a critical role in tumorigenesis, cancer progression, and immune suppression. Recently, neutrophils have attracted the attention of researchers, immunologists, and oncologists because of their potential role in orchestrating immune evasion in human diseases including cancer, which has led to a hot debate redefining the contribution of neutrophils in tumor progression and immunity. To make this debate fruitful, this review seeks to provide a recent update about the contribution of neutrophils in immune suppression and tumor progression. Here, we first described the molecular pathways through which neutrophils aid in cancer progression and orchestrate immune suppression/evasion. Later, we summarized the underlying molecular mechanisms of neutrophil-mediated therapy resistance and highlighted various approaches through which neutrophil antagonism may heighten the efficacy of the immune checkpoint blockade therapy. Finally, we have highlighted several unsolved questions and hope that answering these questions will provide a new avenue toward immunotherapy revolution.

Insights Into the Host Contribution of Endocrine Associated Immune-Related Adverse Events to Immune Checkpoint Inhibition Therapy

Blockade of immune checkpoints transformed the paradigm of systemic cancer therapy, enabling substitution of a cytotoxic chemotherapy backbone to one of immunostimulation in many settings. Invigorating host immune cells against tumor neo-antigens, however, can induce severe autoimmune toxicity which in many cases requires ongoing management. Many immune-related adverse events (irAEs) are clinically and pathologically indistinguishable from inborn errors of immunity arising from genetic polymorphisms of immune checkpoint genes, suggesting a possible shared driver for both conditions. Many endocrine irAEs, for example, have analogous primary genetic conditions with varied penetrance and severity despite consistent genetic change. This is akin to onset of irAEs in response to immune checkpoint inhibitors (ICIs), which vary in timing, severity and nature despite a consistent drug target. Host contribution to ICI response and irAEs, particularly those of endocrine origin, such as thyroiditis, hypophysitis, adrenalitis and diabetes mellitus, remains poorly defined. Improved understanding of host factors contributing to ICI outcomes is essential for tailoring care to an individual’s unique genetic predisposition to response and toxicity, and are discussed in detail in this review.

Chemokines and NSCLC: Emerging role in prognosis, heterogeneity, and therapeutics

Lung cancer persists to contribute to one-quarter of cancer-associated deaths. Among the different histologies, non-small cell lung cancer (NSCLC) alone accounts for 85% of the cases. The development of therapies involving immune checkpoint inhibitors and angiogenesis inhibitors has increased patients' survival probability and reduced mortality rates. Developing targeted therapies against essential genetic alterations also translates to better treatment strategies. But the benefits still seem farfetched due to the development of drug resistance and refractory tumors. In this review, we have highlighted the interplay of different tumor microenvironment components, essentially discussing the chemokine families (CC, CXC, C, and CX3C) that regulate the tumor biology in NSCLC and promote tumor growth, metastasis, and associated heterogeneity. The development of therapeutics and prognostic markers is a complex and multipronged approach. However, some essential chemokines can act as critical players for being considered potential prognostic markers and therapeutic targets.

Increased Circulating Levels of CRP and IL-6 and Decreased Frequencies of T and B Lymphocyte Subsets Are Associated With Immune-Related Adverse Events During Combination Therapy With PD-1 Inhibitors for Liver Cancer

Background

Programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) immune-related adverse events (irAEs) are inevitable in patients with liver cancer. Although the incidence of severe irAEs is low, but can result in fatal consequences. To date, only a few commonly used clinical biomarkers have been reported.

Aim

To assess commonly used clinical biomarkers associated with the occurrence of irAEs to enable better management of irAEs by clinicians.

Methods

We retrospectively reviewed patients with liver cancer treated with at least one cycle of PD-1 immune checkpoint inhibitors (ICIs) combined with tyrosine kinase inhibitors (TKIs). IrAEs were documented according to the common terminology criteria for adverse events version 5. Clinical and laboratory parameters were also evaluated.

Results

A total of 67 patients were included, 36 with irAEs and 31 without irAEs. A total of 104 adverse events occurred; 83 of these events were grade 1/2 (G1/G2), 21 were grade 3/4 (G3/G4), and one died of G4 hepatitis. Patients with irAEs had higher levels of C-reactive protein (CRP) and interleukin-6 (IL-6) and lower levels of lymphocyte subsets, except natural killer (NK) cell counts, than those without irAEs (P <0.05). Patients who experienced G3/G4 irAEs had higher levels of CRP and IL-6 and lower levels of CD4+ T lymphocytes and B lymphocytes than those who experienced G1/G2 irAEs (P <0.05). Of note, impairments in liver function and routine blood tests were also observed (P <0.05). The results of univariate and multivariate analyses for any grade of irAEs revealed that the combination of sintilimab and lenvatinib (P= 0.004, odds ratio [OR]: 7.414, 95% confidence interval [95% CI]: 1.925–28.560) and CRP ≥8.2 mg/L (P= 0.024, OR: 3.727, CI: 1.185–11.726) were independent risk factors. Univariate and multivariate analyses of the risk factors of G3/G4 irAEs suggested that the combination of sintilimab and lenvatinib was a potential risk factor (P = 0.049, OR: 8.242, CI: 1.006–67.532).

Conclusion

Changes in patient CRP, IL-6, and lymphocyte subsets were associated with irAE onset and may act as potential biomarkers of irAEs. Impairments in liver function and routine blood tests owing to the occurrence of irAEs may become new concerns for clinicians.

Longitudinal plasma proteomic profiling of patients with non-small cell lung cancer undergoing immune checkpoint blockade

Background

Immune checkpoint inhibitors (ICIs) have revolutionized the cancer therapy landscape due to long-term benefits in patients with advanced metastatic disease. However, robust predictive biomarkers for response are still lacking and treatment resistance is not fully understood.

Methods

We profiled approximately 800 pre-treatment and on-treatment plasma proteins from 143 ICI-treated patients with non-small cell lung cancer (NSCLC) using ELISA-based arrays. Different clinical parameters were collected from the patients including specific mutations, smoking habits, and body mass index, among others. Machine learning algorithms were used to identify a predictive signature for response. Bioinformatics tools were used for the identification of patient subtypes and analysis of differentially expressed proteins and pathways in each response group.

Results

We identified a predictive signature for response to treatment comprizing two proteins (CXCL8 and CXCL10) and two clinical parameters (age and sex). Bioinformatic analysis of the proteomic profiles identified three distinct patient clusters that correlated with multiple parameters such as response, sex and TNM (tumors, nodes, and metastasis) staging. Patients who did not benefit from ICI therapy exhibited significantly higher plasma levels of several proteins on-treatment, and enrichment in neutrophil-related proteins.

Conclusions

Our study reveals potential biomarkers in blood plasma for predicting response to ICI therapy in patients with NSCLC and sheds light on mechanisms underlying therapy resistance.

Risk Factors and Biomarkers for Immune-Related Adverse Events: A Practical Guide to Identifying High-Risk Patients and Rechallenging Immune Checkpoint Inhibitors

Immune-related adverse events (irAEs) are a range of complications associated with the use of immune-checkpoint inhibitors (ICIs). Two major classes of ICIs widely used are Cytotoxic T-Lymphocyte Antigen 4 (CTLA4) and Programmed Cell death-1 (PD-1)/Programmed death-ligand 1 (PD-L1) inhibitors. High-grade irAEs are life-threatening and often cause a severe decline in performance status in such that patients do not qualify for any further anticancer treatments. It is difficult to generalize the evidence in the current literature on risk factors or biomarkers for the entire class of ICIs as the studies so far are either disease-specific (e.g., lung cancer or melanoma) or ICI agent-specific (e.g., pembrolizumab, ipilimumab) or irAE-specific (e.g., pneumonitis or gastritis). In this review, risk factors and biomarkers to consider before initiating or monitoring ICI are listed with a practical purpose in day-to-day practice. Risk factors are grouped into demographics and social history, medical history, and medication history, tumor-specific and agent-specific risk factors. A higher risk of irAE is associated with age <60 years, high body mass index, women on CTLA4 and men on PD-1/PD-L1 agents, and chronic smokers. Patients with significant kidney (Stage IV-V), cardiac (heart failure, coronary artery disease, myocardial infarction, hypertension), and lung (asthma, pulmonary fibrosis, and chronic obstructive pulmonary disease) are at a higher risk of respective organ-specific irAEs. Pre-existing autoimmune disease and chronic use of certain drugs (proton pump inhibitors, diuretics, anti-inflammatory drugs) also increase the irAE-risk. Biomarkers are categorized into circulating blood counts, cytokines, autoantibodies, HLA genotypes, microRNA, gene expression profiling, and serum proteins. The blood counts and certain protein markers (albumin and thyroid-stimulating hormone) are readily accessible in current practice. High neutrophil-lymphocyte ratio, eosinophil/monocyte/lymphocyte counts; TSH and troponins at diagnosis and drop in the white count and lymphocyte count can predict irAE. Other biomarkers with limited evidence are cytokines, autoantibodies, HLA genotypes, microRNA, and gene expression profiling. With fast-expanding approvals for ICIs in various cancer types, knowledge on risk factors and biomarkers can help providers assess the irAE-risk of their patients. Prospective disease and agent-specific studies are needed to provide further insight on this essential aspect of ICI therapy.

Association of Baseline and Pharmacodynamic Biomarkers With Outcomes in Patients Treated With the PD-1 Inhibitor Budigalimab

Budigalimab, a novel anti-PD-1 monoclonal antibody, demonstrated efficacy and biomarker pharmacodynamics in patients with head and neck squamous cell carcinoma (HNSCC) or non-small cell lung cancer (NSCLC) consistent with those reported by other PD-1 inhibitors. Herein are presented additional outcomes of biomarker analyses from the phase 1 study of budigalimab monotherapy in patients with HNSCC and NSCLC (NCT03000257). PD-1 inhibitor naive patients with advanced HNSCC (n=41) or NSCLC (n=40) received budigalimab intravenously at 250 mg every 2 weeks (Q2W) or 500 mg Q4W until progression. Archival tumor specimens were evaluated by immunohistochemistry for CD8 and tumor PD-1 ligand 1 (PD-L1) expression, RNA, and whole-exome sequencing. Serum and whole blood samples were acquired at baseline and at select on-treatment time points. As of October 2019, best overall response of 15% in HNSCC and 18% in NSCLC was observed in all treated patients; both cohorts reported responses in PD-L1+ and PD-L1- tumors. Treatment with budigalimab was associated with increases in multiple soluble biomarkers including interferon gamma-induced chemokines. Expanded overall T-cell counts, total CD8 T-cell counts, and percentages of CD8+CD45RA-CD62L- effector memory T cells were observed at cycle 1, day 15 in responders. Univariate analysis demonstrated an association between prolonged progression-free survival and higher tumor mutational burden/neoantigen load, smaller tumor size, lower platelet-lymphocyte ratios, lower CCL23, lower colony-stimulating factor 1, and lower interleukin-6 levels at baseline. The biomarker analysis presented herein identified additional early pharmacodynamic biomarkers associated with anti-PD-1 activity and improved clinical responses to budigalimab in patients with advanced HNSCC and NSCLC.

Pre-treatment serum protein levels predict survival of non-small cell lung cancer patients without durable clinical benefit by PD-1/L1 inhibitors

While PD-1/L1 inhibitors are characterized by durable tumor control, they also prolong survival without prolongation of progression-free survival (PFS) in part of patients. However, little is known about the factors and mechanisms involved in this. Between December 2015 and September 2018, 106 patients with advanced non-small cell lung cancer treated with ICI monotherapy were enrolled in a prospective-observational study. Sixty-nine of whom progressed or died within 6 months after ICI initiation were defined as patients without durable clinical benefit (NDBs). Clinical factors and 39 serum proteins before ICI initiation and at the time of progressive disease (PD) were explored for an association with overall survival (OS) and OS after PD (OS-PD). As a result, median PFS, OS, and OS-PD were 44 days [95% confidence interval (CI): 39-56), 211 days (95% CI: 158-425), and 193 days (95% CI: 118-349), respectively. By multivariate analysis for OS, CRP (> 1.44 mg/dl) [HR 2.59 (95% CI:1.33-5.04), P = 0.005] and follistatin (> 685 pg/ml) [HR 2.29 (95% CI:1.12-4.69), P = 0.023] before ICI initiation were significantly predictive. Notably, no serum protein at the time of PD was predictive for OS-PD. There were also no serum predictive factors of OS in the 33 patients with durable clinical benefit. In conclusion, serum levels of CRP and follistatin before ICI initiation, not at the time of PD, are predictive for OS in NDBs, suggesting long-term survivor in NDBs are predetermined by the immune status before ICI initiation.

A Potential Serum Biomarker for Screening Lung Cancer Risk in High Level Environmental Radon Areas: A Pilot Study

Radon is a major cause of lung cancer (LC) deaths among non-smokers worldwide. However, no serum biomarker for screening of LC risk in high residential radon (HRR) areas is available. Therefore, the aim of this study was to determine diagnostic values of serum carcinoembryonic antigen (CEA), cytokeratin 19 fragment (Cyfra21-1), human epididymis protein 4 (HE4), interleukin 8 (IL-8), migration inhibitory factor (MIF), tumor nuclear factor-alpha (TNF-α) and vascular endothelial growth factors (VEGF) occurring in high radon areas. Seventy-five LC non-smoker patients and seventy-five healthy controls (HC) were enrolled in this study. Among the HC groups, twenty-five HC were low residential radon (LRR) and fifty HC were HRR. Significantly higher (p < 0.0004) serum levels of CEA, Cyfra21-1, IL-8 and VEGF were found in the LC compared with the LRR and HRR groups. More importantly, significantly higher levels (p < 0.009) of serum CEA, Cyfra21-1 and IL-8 were observed in HRR compared with the LRR group. Likewise, a ROC curve demonstrated that serum CEA and Cyfra21-1 could better distinguish LC risk from HRR groups than IL-8. These results indicated that serum CEA and Cyfra21-1 were significantly increased in the HRR group and may be considered as potential biomarkers for individuals at high-risk to develop LC.

Immune checkpoint blockade in the treatment of malignant tumor: current statue and future strategies

After being stagnant for decades, there has finally been a paradigm shift in the treatment of cancer with the emergence and application of immune checkpoint inhibitors (ICIs). The most extensively utilized ICIs are targeting the pathways involving programmed death-1 (PD-1) and cytotoxic T-lymphocyte associated protein 4 (CTLA-4). PD-1, as an crucial immune inhibitory molecule, by and large reasons the immune checkpoint response of T cells, making tumor cells get away from immune surveillance. Programmed cell death ligand-1 (PD-L1) is exceptionally expressed in most cancers cells and approves non-stop activation of the PD-1 pathway in the tumor microenvironment. PD-1/PD-L1 inhibitors can block the combination of PD-1 and PD-L1, inhibit hostile to regulatory signals, and restore the activity of T cells, thereby bettering immune response. The current researchers assume that the efficacy of these drugs is related to PD-L1 expression in tumor tissue, tumor mutation burden (TMB), and other emerging biomarkers. Although malignant tumors can benefit from the immunotherapy of PD-1/PD-L1 inhibitors, formulating a customized medication model and discovering biomarkers that can predict efficacy are the new trend in the new era of malignant tumor immunotherapy. This review summarizes the mechanism of action of PD-1/PD-L1 inhibitors, their clinical outcomes on various malignant tumors, their efficacy biomarkers, as well as predictive markers of irAEs.

TGFβ Signaling Activated by Cancer-Associated Fibroblasts Determines the Histological Signature of Lung Adenocarcinoma

Invasive lung adenocarcinoma (LADC) can be classified histologically as lepidic, acinar, papillary, micropapillary, or solid. Most LADC tumors manifest several of these histological subtypes, with heterogeneity being related to therapeutic resistance. We report here that in immunodeficient mice, human LADC cells form tumors with distinct histological features, MUC5AC-expressing solid-type or cytokeratin 7 (CK7)-expressing acinar-type tumors, depending on the site of development, and that a solid-to-acinar transition (SAT) could be induced by the tumor microenvironment. The TGFβ-Smad signaling pathway was activated in both tumor and stromal cells of acinar-type tumors. Immortalized cancer-associated fibroblasts (CAF) derived from acinar-type tumors induced SAT in 3D cocultures with LADC cells. Exogenous TGFβ1 or overexpression of an active form of TGFβ1 increased CK7 expression and reduced MUC5AC expression in LADC cells, and knockdown of Tgfb1 mRNA in CAFs attenuated SAT induction. RNA-sequencing analysis suggested that angiogenesis and neutrophil recruitment are associated with SAT in vivo. Our data indicate that CAF-mediated paracrine TGFβ signaling induces remodeling of tumor tissue and determines the histological pattern of LADC, thereby contributing to tumor heterogeneity. SIGNIFICANCE: CAFs secrete TGFβ to induce a solid-to-acinar transition in lung cancer cells, demonstrating how the tumor microenvironment influences histological patterns and tumor heterogeneity in lung adenocarcinoma.

Role of Cytokines and Chemokines in NSCLC Immune Navigation and Proliferation

With over a million deaths every year around the world, lung cancer is found to be the most recurrent cancer among all types. Nonsmall cell lung carcinoma (NSCLC) amounts to about 85% of the entire cases. The other 15% owes it to small cell lung carcinoma (SCLC). Despite decades of research, the prognosis for NSCLC patients is poorly understood with treatment options limited. First, this article emphasises on the part that tumour microenvironment (TME) and its constituents play in lung cancer progression. This review also highlights the inflammatory (pro- or anti-) roles of different cytokines (ILs, TGF-β, and TNF-α) and chemokine (CC, CXC, C, and CX3C) families in the lung TME, provoking tumour growth and subsequent metastasis. The write-up also pinpoints recent developments in the field of chemokine biology. Additionally, it covers the role of extracellular vesicles (EVs), as alternate carriers of cytokines and chemokines. This allows the cytokines/chemokines to modulate the EVs for their secretion, trafficking, and aid in cancer proliferation. In the end, this review also stresses on the role of these factors as prognostic biomarkers for lung immunotherapy, apart from focusing on inflammatory actions of these chemoattractants.

Systemic inflammation and pro-inflammatory cytokine profile predict response to checkpoint inhibitor treatment in NSCLC: a prospective study

Treatment with single agent immune checkpoint inhibitors (ICIs) has tremendously changed second line therapy in NSCLC. However, there are still no reliable biomarkers predicting response and survival in this group of patients. PD-L1 revealed to be a correlating, but no perfect marker. Therefore, we sought to investigate in this prospective study, whether inflammation status and cytokine profile could serve as additional biomarkers guiding treatment decision for single agent ICIs in NSCLC. 29 stage IV NSCLC patients receiving single agent PD-1 checkpoint-inhibitor in second line were prospectively enrolled. Inflammatory scores and cytokine profiles (IL-6, IL-8, IL-10, IFN-γ and TNFα) have been obtained before treatment and at the time of the first staging. Cytokine profiles were correlated with response and survival. Patients with signs of pre-therapeutic inflammation (elevated, NLR, SII, IL-6, IL-8) showed significantly lower response to ICI treatment and reduced PFS. Contrary, elevated levels of IFN-γ revealed to characterize a subgroup of patients, who significantly benefits from ICI treatment. Furthermore, low systemic inflammation and high levels of IFN-γ characterized patients with long term-response to ICI treatment. Pre-therapeutic assessment of inflammation and cytokine profiles has the ability to predict response and survival in NSCLC patients treated with single agent ICIs.

Bloodborne Cytokines for Predicting Clinical Benefits and Immune-Related Adverse Events in Advanced Non-Small Cell Lung Cancer Treated With Anti-Programmed Cell Death 1 Inhibitors

BACKGROUND

Programmed cell death ligand 1 is a biomarker of immune checkpoint inhibitors (ICIs) for treating advanced non-small-cell lung cancer (NSCLC). Here, we evaluated serum proteins from patients with advanced NSCLC treated with ICIs to determine their potential as noninvasive predictive biomarkers for efficacy and immune-related adverse events (irAEs).

PATIENTS AND METHODS

Patients with advanced NSCLC who received nivolumab or pembrolizumab monotherapy until disease progression or unacceptable toxicity were integrated with previously reported nivolumab-treated patients. Blood samples were collected serially from baseline until the disease progressed. Serum protein levels were quantified using the Luminex assay. Associations of clinical benefit (CB) and onset of irAEs with serum protein levels were evaluated.

RESULTS

Sixty-three patients with advanced NSCLC were studied, and we used 63 and 47 paired serum samples at baseline and the second sampling point, respectively, for efficacy analysis. Baseline growth-regulated oncogene 1 (GRO-1) levels were significantly lower in durable CB (DCB) patients than in non-DCB patients (P < .05). Changes in monocyte chemoattractant protein 1 (MCP-1) levels significantly decreased between baseline and the second sampling point (P < .05). Patients with the low GRO-1/decreased MCP-1 subtype showed significantly longer progression-free survival (PFS) and overall survival (OS) than the high GRO-1/increased MCP-1 subgroup did (median PFS, not reached vs. 47 days, P < .0001; median OS, 985 days vs. 148 days, P = .0002, respectively). Elevated GRO-1 levels were associated with immune-related adverse event onset.

CONCLUSIONS

Serum GRO-1 and MCP-1 levels can identify patients with advanced NSCLC who are likely to benefit from ICI treatment. Time-course tracing of these protein levels might be valuable in ICI treatment.

Circulating Biomarkers of Response and Toxicity of Immunotherapy in Advanced Non-Small Cell Lung Cancer (NSCLC): A Comprehensive Review

Simple Summary

Although immunotherapy has dramatically revolutionized non-small cell lung cancer (NSCLC) treatment, not all the patients will benefit from this innovative therapy. The identification of potential biomarkers able to predict efficacy and toxicity of immunotherapy represents an urgent need for tailored treatment regimens. Liquid biopsy is a minimally invasive and economical tool that could provide important information about patients’ selection and treatment monitoring. Currently, several blood biomarkers are under investigation (circulating immune and tumor cells, soluble immunological mediators, peripheral blood cells). Prospective clinical trials are needed to validate their use in clinical practice.

Abstract

Immune checkpoint inhibitors (ICIs) targeting the programmed cell death (PD)-1 protein and its ligand, PD-L1, and cytotoxic T-lymphocyte-associated antigen (CTLA)-4, have revolutionized the management of patients with advanced non-small cell lung cancer (NSCLC). Unfortunately, only a small portion of NSCLC patients respond to these agents. Furthermore, although immunotherapy is usually well tolerated, some patients experience severe immune-related adverse events (irAEs). Liquid biopsy is a non-invasive diagnostic procedure involving the isolation of circulating biomarkers, such as circulating tumor cells (CTC), cell-free DNA (cfDNA), and microRNAs (miRNAs). Thanks to recent advances in technologies, such as next-generation sequencing (NGS) and digital polymerase chain reaction (dPCR), liquid biopsy has become a useful tool to provide baseline information on the tumor, and to monitor response to treatments. This review highlights the potential role of liquid biomarkers in the selection of NSCLC patients who could respond to immunotherapy, and in the identification of patients who are most likely to experience irAEs, in order to guide improvements in care.

Biomarkers of Checkpoint Inhibitor Induced Immune-Related Adverse Events-A Comprehensive Review

Immune checkpoint inhibitors (ICIs) have substantially improved the prognosis of patients with different types of cancer. Through blockade of cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1), negative feedback mechanisms of the immune system are inhibited, potentially resulting in very durable anti-tumor responses. Despite their promise, ICIs can also elicit auto-immune toxicities. These immune-related adverse events (irAEs) can be severe and sometimes even fatal. Therefore, being able to predict severe irAEs in patients would be of added value in clinical decision making. A search was performed using “adverse events”, “immune checkpoint inhibitor”, “biomarker”, and synonyms in PubMed, yielding 3580 search results. After screening title and abstract on the relevance to the review question, statistical significance of reported potential biomarkers, and evaluation of the remaining full papers, 35 articles were included. Five additional reports were obtained by means of citations and by using the similar article function on PubMed. The current knowledge is presented in comprehensive tables summarizing blood-based, immunogenetic and microbial biomarkers predicting irAEs prior to and during ICI therapy. Until now, no single biomarker has proven to be sufficiently predictive for irAE development. Recommendations for further research on this topic are presented.

CD24, not CD47, negatively impacts upon response to PD-1/L1 inhibitors in non-small-cell lung cancer with PD-L1 tumor proportion score < 50

CD24, a heavily glycosylated glycosylphosphatidylinositol–anchored surface protein, inhibits phagocytosis as potently as CD47. The relationship between such anti‐phagocytic factors and the immune response with immune–checkpoint inhibitors (ICI) remains unexplored. We evaluated CD24 and CD47 tumor proportion scores (TPS) in 68 of the 106 patients with advanced non–small‐cell lung cancer who participated in a prospective observational study of ICI treatment. We also explored the impact of CD24 TPS and CD47 TPS on ICI efficacy and serum cytokine changes. CD24 positivity (TPS ≥ 1) was negatively associated with progression–free survival (PFS) of ICI when PD‐L1 TPS was < 50 (median PFS; 37 vs 127 d, P = .033), but there was no association when PD‐L1 TPS was ≥ 50 (median PFS; 494 vs 144 d, P = .168). CD24 positivity was also related to significantly higher increase of CCL2 from baseline to 4‐6 wk later, and such increase was notably observed only when PD‐L1 TPS < 50 (P = .0004). CCL2 increase after ICI initiation was negatively predictive for survival after initiation of ICI (median survival time; not reached vs 233 d; P = .028). CD47 TPS high (≥60) significantly suppressed the increase in vascular endothelial growth factor (VEGF)‐A, D and PDGF‐AB/BB after ICI initiation. There was no association, however, between CD47 tumor expression and the efficacy of ICI. In conclusion, CD24, not CD47, is a candidate negative predictive marker of ICI in advanced, non–small‐cell lung cancer with PD‐L1 TPS < 50. Tumor expression of both CD24 and CD47 was associated with changes in factors related to monocytes and angiogenesis after ICI initiation (UMIN000024414).

Uncoupling Therapeutic Efficacy from Immune-Related Adverse Events in Immune Checkpoint Blockade

Immunotherapy with monoclonal antibodies targeting immune checkpoint molecules, including programmed death-1 (PD-1), PD ligand-1 (PD-L1), and cytotoxic T-lymphocyte-associated antigen (CTLA)-4, has become prominent in the treatment of many types of cancer. However, a significant number of patients treated with immune checkpoint inhibitors (ICIs) develop immune-related adverse events (irAEs). irAEs can affect any organ system, and although most are clinically manageable, irAEs can result in mortality or long-term morbidity. Factors that can predict irAEs remain elusive. Understanding the etiology of ICI-induced irAEs and ways to limit these adverse events are needed. In this review, we provide basic science and clinical insights on the mechanisms responsible for ICI efficacy and ICI-induced irAEs. We further provide insights into approaches that may uncouple irAEs from the ability of ICIs to kill tumor cells.

Interleukin-8: A chemokine at the intersection of cancer plasticity, angiogenesis, and immune suppression

Tumor progression relies on the ability of cancer cells to effectively invade surrounding tissues and propagate. Among the many mechanisms that contribute to tumor progression is the epithelial-to-mesenchymal transition (EMT), a phenotypic plasticity phenomenon that increases the cancer cells' motility and invasiveness and influences their surrounding microenvironment by promoting the secretion of a variety of soluble factors. One such factor is IL-8, a chemokine with multiple pro-tumorigenic roles within the tumor microenvironment (TME), including stimulating proliferation or transformation of tumor cells into a migratory or mesenchymal phenotype. Further, IL-8 can increase tumor angiogenesis or recruit larger numbers of immunosuppressive cells to the tumor. Prognostically, observations in many tumor types show that patients with higher levels of IL-8 at baseline experience worse clinical outcomes. Additionally, studies have shown that the chemokine directly contributes to the development of resistance to both chemotherapy and molecularly targeted agents. More recently, clinical studies evaluating levels of IL-8 in patients receiving immune checkpoint inhibition (ICI) therapy deduced that myeloid tumor infiltration driven by IL-8 contributes to resistance to ICI agents and that peripheral IL-8 can predict outcomes to ICI therapy. Further, pre-clinical data demonstrate that targeting IL-8 or its receptors enables improved tumor killing by immune cells, and treatment strategies combining blockade of the IL-8/IL-8R axis with ICI ultimately improve anti-tumor efficacy. Based on these results and the prognostic capacity of IL-8, there are a number of ongoing clinical trials evaluating the addition of IL-8 targeting strategies to immune-based therapies.

Adverse Effects of Anti-PD-1/PD-L1 Therapy in Non-small Cell Lung Cancer

Currently, immunotherapy has shown great efficacy in clinical trials, and monoclonal antibodies directed against immune checkpoint PD-1/PD-L1 have shown encouraging results in first-line or second-line treatment of non-small cell lung cancer patients. Meanwhile, anti-PD-1/PD-L1 immune checkpoint drugs combined with other treatments, such as chemotherapy, targeted therapy as well as anti-CTLA-4 checkpoint therapy, are considered an attractive treatment with higher efficacy. However, toxicity associated with PD-1/PD-L1 blockade is worth attention. Understanding the adverse effects caused by anti-PD-1/PD-L1 immunosuppressive agents is vital to guide the clinical rational use of drug. In this review, we summarized the adverse effects that occurred during the clinical use of anti-PD-1/PD-L1 inhibitors in the treatment of non-small cell lung cancer and discussed how to effectively manage and respond to these adverse reactions.

Secreted BMP antagonists and their role in cancer and bone metastases

Bone morphogenetic proteins (BMPs) are multifunctional secreted cytokines that act in a highly context-dependent manner. BMP action extends beyond the induction of cartilage and bone formation, to encompass pivotal roles in controlling tissue and organ homeostasis during development and adulthood. BMPs signal via plasma membrane type I and type II serine/threonine kinase receptors and intracellular SMAD transcriptional effectors. Exquisite temporospatial control of BMP/SMAD signalling and crosstalk with other cellular cues is achieved by a series of positive and negative regulators at each step in the BMP/SMAD pathway. The interaction of BMP ligand with its receptors is carefully controlled by a diverse set of secreted antagonists that bind BMPs and block their interaction with their cognate BMP receptors. Perturbations in this BMP/BMP antagonist balance are implicated in a range of developmental disorders and diseases, including cancer. Here, we provide an overview of the structure and function of secreted BMP antagonists, and summarize recent novel insights into their role in cancer progression and bone metastasis. Gremlin1 (GREM1) is a highly studied BMP antagonist, and we will focus on this molecule in particular and its role in cancer. The therapeutic potential of pharmacological inhibitors for secreted BMP antagonists for cancer and other human diseases will also be discussed.

Investigational Biomarkers for Checkpoint Inhibitor Immune-Related Adverse Event Prediction and Diagnosis

BACKGROUND

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of multiple cancers. However, these promising therapies may also cause immune-related adverse events (irAEs) in a substantial proportion of patients. These autoimmune phenomena may affect almost any organ system and may occur at almost any point in therapy. In some instances, these toxicities are life-threatening and potentially permanent. Diverse clinical presentation and unpredictable timing further complicate their anticipation and diagnosis.

CONTENT

To improve patient safety and selection for ICI use, biomarkers for irAE diagnosis and prediction are under development. Clinicians may use traditional laboratory markers such as routine chemistries, creatinine clearance, thyroid function tests, and serum cortisol/adrenocorticotrophic hormone to monitor for specific irAEs, but noted aberrations may not necessarily represent an immune-mediated etiology. Novel biomarkers have the potential to be more specific to assist in the diagnosis of irAEs. The prediction of irAEs is more challenging. Apart from a history of autoimmune disease, no other clinical parameters are routinely used to project risk. Biomarker candidates under investigation for irAE diagnosis and prediction include blood cell analysis, chemokines/cytokines, autoantibodies, and genetic predisposition, such as human leukocyte antigen haplotype. Among other emerging candidates are immune-cell subsets, T-cell repertoire, fecal microbiome, tumor genomics, and radiomic characterization.

SUMMARY

Several conventional laboratory indexes of end-organ dysfunction are currently in routine clinical use for irAE monitoring and diagnosis. Novel biomarkers for the prediction and diagnosis of these irAEs, which primarily characterize patient immune function, represent an area of active investigation.

Checkpoint Inhibitor Pneumonitis: Mechanisms, Characteristics, Management Strategies, and Beyond

PURPOSE OF REVIEW

Checkpoint inhibitor pneumonitis (CIP) is a toxicity of immune checkpoint blockade (ICB) that can be highly morbid and at times fatal. Here, we review the proposed biologic mechanisms of CIP, epidemiology and risk factors for CIP development, diagnostic work-up and management strategies for CIP, and future directions of CIP research.

RECENT FINDINGS

CIP incidence appears to be greater in real-world populations and may continue to rise as FDA approvals for ICB continue to expand to multiple malignancies. Multiple retrospective studies and case series have identified potential risk factors for CIP. Several society guidelines have helped to unify the classification of CIP severity and standardize treatment approaches but significant gaps remain, including formal validated diagnostic criteria for CIP. While significant strides have been made in enhancing the knowledge and management of CIP, ongoing research is needed to continue to advance our understanding of the biologic underpinnings of CIP, as well as optimize diagnostic and management strategies for this potentially devastating toxicity.

Proteolytic chemokine cleavage as a regulator of lymphocytic infiltration in solid tumors

In the past decade, immune-based therapies such as monoclonal antibodies against tumor epitopes or immune checkpoint inhibitors have become an integral part of contemporary cancer treatment in many entities. However, a fundamental prerequisite for the success of such therapies is a sufficient trafficking of tumor-infiltrating lymphocytes into the tumor microenvironment. This infiltration is facilitated by chemokines, a group of about 50 small proteins capable of chemotactically guiding leukocytes. Proteolytic inactivation of chemokines leading to an impaired infiltration of immune effector cells appears to be an efficient immune escape mechanism of solid cancers.

The CXCR3 and CX3CR1 chemokine receptor ligands CXCL9-11 and CX3CL1, respectively, are mainly responsible for the tumor-suppressive lymphocytic infiltration into the tumor micromilieu. Their structure explains the biochemical basis of their proteolytic cleavage, while in vivo data from mouse models and patient samples shed light on the corresponding processes in cancer. The emerging roles of proteases, e.g., matrix metalloproteinases, cathepsins, and dipeptidyl peptidase 4, in chemokine inactivation define new resistance mechanisms against immunotherapies and identify attractive new targets to enhance immune intervention in cancer.

Immune-Related Adverse Events by Immune Checkpoint Inhibitors Significantly Predict Durable Efficacy Even in Responders with Advanced Non-Small Cell Lung Cancer

Background

Although predictive value of immune‐related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been suggested by several studies, their assessments were insufficient because patients were categorized only by the occurrence of irAEs. It has not been elucidated whether irAEs also play a significant role even in responders.

Materials and Methods

Between December 2015 and September 2018, 106 patients with advanced non‐small cell lung cancer treated with ICIs were enrolled in our prospective biomarker study. Twenty‐three of these were responders, defined as those with complete or partial response. We investigated the proportion of irAEs among overall and responders. For responders, progression‐free survival (PFS) and overall survival of ICIs were compared between those with and without irAEs. As an exploratory analysis, we measured 41 proteins from peripheral blood before and after ICI treatment.

Results

The proportion of irAEs was significantly higher in responders than nonresponders (65.2% vs. 19.3%, p < .01). Among responders, clinical characteristics did not differ regardless of the occurrence of irAEs. However, there was a significant difference in PFS among responders (irAE group 19.1 months vs. non‐irAE group 5.6 months; hazard ratio: 0.30 [95% confidence interval: 0.10–0.85]; p = .02). Of 41 protein analyses, fibroblast growth factor‐2 at baseline and monocyte chemoattractant protein fold change showed significant differences between them (p < .04).

Conclusion

Although this is a small sample–sized study, irAE might be a predictive factor of durable efficacy, even in patients who responded to ICIs. Investigation into the significance of irAEs in responders will contribute to the establishment of optimal administration of ICI.

Implications for Practice

Although the predictive value of immune‐related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) has been suggested by several studies, it has not been elucidated whether irAEs also play a significant role even in responders. This study showed that more than 60% of responders had irAEs. It demonstrated the strong correlation between irAEs and efficacy even in responders. Investigation into the significance of irAEs in responders will contribute to the establishment of optimal administration of ICI.

Immune‐related adverse events might be a predictive factor of efficacy, even I patients who respond to immune checkpoint inhibitor therapy. This study investigated the significance of immune‐related adverse events in patients with non‐small cell lung cancer who had complete or partial response after treatment with immune checkpoint inhibitors.

Enumeration And Characterization Of Circulating Tumor Cells And Its Application In Advanced Gastric Cancer

Background

Advanced gastric cancer (aGC) has a high global incidence and a high mortality rate and because of its high malignancy and heterogeneity, the existing methods for prognosis are limited, and a new treatment model is necessary. Circulating tumor cells (CTCs) could be considered as a “liquid biopsy” for tumor diagnosis and for monitoring treatment responses and predicting clinical outcome. Clinical studies support the efficacy of programmed cell death 1 (PD-1) immunotherapy in a subset of aGC.

Methods

Cell capture efficiency, as described by the CanPatrol CTC enrichment technique, was validated using artificial blood samples as well as blood samples from 32 aGC patients. Clinicopathologic data of patients were collected from the hospital information system. We used CanPatrol for CTC isolation, classification, and clinical analysis.

Results

A cell capture efficiency of >80% was achieved. Significant correlation was observed between CTC enumeration and clinicopathology parameters, including the Lauren classification (r=0.470, P=0.008), perineural invasion (r=0.393, P=0.029), TNM stage (r=0.740, P<0.001), and Ki-67 level (r=0.510, P=0.005). When compared to the traditional methods, monitoring CTC subtypes exhibits higher sensitivity of evaluating the disease status. Enumeration of epithelial CTC subset and its relative abundance in the total CTC pool are highly correlated with clinical efficacy. CTC programmed cell death ligand-1 (PD-L1) could be successfully detected for immunotherapy in addition to PD-L1 immunohistochemistry and microsatellite instability.

Conclusion

We provide a new method that allows for the simple and effective detection of CTCs in aGC. It has potential clinical applications in monitoring prognosis and guiding future individualized immunotherapy.

Plasma Biomarkers and Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer: New Tools for Better Patient Selection?

Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape for patients with non-small cell lung cancer (NSCLC). Although some patients can experience important response rates and improved survival, many others do not benefit from ICIs developing hyper-progressive disease or immune-related adverse events. This underlines the need to select biomarkers for ICIs use in order to better select patients. There is currently no universally validated robust biomarker for daily use of ICIs. Programmed death-ligand 1 (PD-L1) or tumor mutational burden (TMB) are sometimes used but still have several limitations. Plasma biomarkers are a promising approach in ICI treatment. This review will describe the development of novel plasma biomarkers such as soluble proteins, circulating tumor DNA (ctDNA), blood TMB, and blood microbiome in NSCLC patients treated with ICIs and their potential use in predicting response and toxicity.

Liquid Biopsy for the Detection of Resistance Mechanisms in NSCLC: Comparison of Different Blood Biomarkers

The use of targeted agents and immunotherapy for the treatment of advanced non-small-cell lung cancer (NSCLC) has made it mandatory to characterize tumor tissue for patient selection. Moreover, the development of agents that are active against specific resistance mechanisms arising during treatment make it equally important to characterize the tumor tissue at progression by performing tissue re-biopsy. Given that tumor tissue is not always available for molecular characterization due to the paucity of diagnostic specimens or problems relating to the carrying out of invasive procedures, the use of liquid biopsy represents a valid approach to overcoming these difficulties. The most common material used for liquid biopsy in this setting is plasma-derived cell free DNA (cfDNA), which originates from cells undergoing apoptosis or necrosis. However, other sources of tumor material can be considered, such as extracellular vesicle (EV)-derived nucleic acids, which are actively secreted from living cells and closely correspond to tumor dynamics. In this review, we discuss the role of liquid biopsy in the therapeutic management of NSCLC with particular regard to targeted therapy and immunotherapy, and analyze the pros and cons of the different types of samples used in this context.