Resistance to immune checkpoint inhibitors in non-small cell lung cancer: biomarkers and therapeutic strategies

A landscape of checkpoint blockade resistance in cancer: underlying mechanisms and current strategies to overcome resistance

The discovery of immune checkpoints and the development of immune checkpoint inhibitors (ICI) have achieved a durable response in advanced-stage cancer patients. However, there is still a high proportion of patients who do not benefit from ICI therapy due to a lack of response when first treated (primary resistance) or detection of disease progression months after objective response is observed (acquired resistance). Here, we review the current FDA-approved ICI for the treatment of certain solid malignancies, evaluate the contrasting responses to checkpoint blockade in different cancer types, explore the known mechanisms associated with checkpoint blockade resistance (CBR), and assess current strategies in the field that seek to overcome these mechanisms. In order to improve current therapies and develop new ones, the immunotherapy field still has an unmet need in identifying other molecules that act as immune checkpoints, and uncovering other mechanisms that promote CBR.

Evaluation of the antitumor effect of neoantigen peptide vaccines derived from the translatome of lung cancer

Emerging evidence suggests that tumor-specific neoantigens are ideal targets for cancer immunotherapy. However, how to predict tumor neoantigens based on translatome data remains obscure. Through the extraction of ribosome-nascent chain complexes (RNCs) from LLC cells, followed by RNC-mRNA extraction, RNC-mRNA sequencing, and comprehensive bioinformatic analysis, we successfully identified proteins undergoing translatome and exhibiting mutations in the cells. Subsequently, novel antigens identification was analyzed by the interaction between their high affinity and the Major Histocompatibility Complex (MHC). Neoantigens immunogenicity was analyzed by enzyme-linked immunospot assay (ELISpot). Finally, in vivo experiments in mice were conducted to evaluate the antitumor effects of translatome-derived neoantigen peptides on lung cancer. The results showed that ten neoantigen peptides were identified and synthesized by translatome data from LLC cells; 8 out of the 10 neoantigens had strong immunogenicity. The neoantigen peptide vaccine group exhibited significant tumor growth inhibition effect. In conclusion, neoantigen peptide vaccine derived from the translatome of lung cancer exhibited significant tumor growth inhibition effect.

Prostaglandin E2 in the Tumor Microenvironment, a Convoluted Affair Mediated by EP Receptors 2 and 4

The involvement of the prostaglandin E2 (PGE2) system in cancer progression has long been recognized. PGE2 functions as an autocrine and paracrine signaling molecule with pleiotropic effects in the human body. High levels of intratumoral PGE2 and overexpression of the key metabolic enzymes of PGE2 have been observed and suggested to contribute to tumor progression. This has been claimed for different types of solid tumors, including, but not limited to, lung, breast, and colon cancer. PGE2 has direct effects on tumor cells and angiogenesis that are known to promote tumor development. However, one of the main mechanisms behind PGE2 driving cancerogenesis is currently thought to be anchored in suppressed antitumor immunity, thus providing possible therapeutic targets to be used in cancer immunotherapies. EP2 and EP4, two receptors for PGE2, are emerging as being the most relevant for this purpose. This review aims to summarize the known roles of PGE2 in the immune system and its functions within the tumor microenvironment. SIGNIFICANCE STATEMENT: Prostaglandin E2 (PGE2) has long been known to be a signaling molecule in cancer. Its presence in tumors has been repeatedly associated with disease progression. Elucidation of its effects on immunological components of the tumor microenvironment has highlighted the potential of PGE2 receptor antagonists in cancer treatment, particularly in combination with immune checkpoint inhibitor therapeutics. Adjuvant treatment could increase the response rates and the efficacy of immune-based therapies.

Chidamide plus envafolimab as subsequent treatment in advanced non-small cell lung cancer patients resistant to anti-PD-1 therapy: A multicohort, open-label, phase II trial with biomarker analysis

BACKGROUND

Combination of chidamide and anti-PD-L1 inhibitor produce synergistic anti-tumor effect in advanced NSCLC patients resistant to anti-PD-1 treatment. However, the effect of chidamide plus envafolimab has not been reported.

AIMS

This study aimed to evaluate the efficacy of chidamide plus envafolimab in advanced NSCLC patients resistant toanti-PD-1 treatment.

MATERIALS AND METHODS

Eligible advanced NSCLC patients after resistant to anti-PD-1 therapy received chidamide and envafolimab. The primary endpoint was objective response rate (ORR). The secondary end points included disease control rate (DCR), progression-free survival (PFS), and safety. The expression of histone deacetylase 2 (HDAC2), PD-L1, and blood TMB (bTMB) was also analyzed.

RESULTS

After a median follow-up of 8.1 (range: 7.6-9.2) months, only two patients achieved partial response. The ORR was 6.7% (2/30), DCR was 50% (15/30), and median PFS (mPFS) was 3.5 (95% confidence interval: 1.9-5.5) months. Biomarker analysis revealed that patients with high-level HDAC2 expression had numerically superior ORR (4.3% vs. 0), DCR (52.2% vs. 0) and mPFS (3.7 vs. 1.4m). Patients with negative PD-L1 had numerically superior DCR (52.2% vs. 33.3%) and mPFS (3.7m vs. 1.8m), so were those with low-level bTMB (DCR: 59.1% vs. 16.7%, mPFS: 3.8 vs.1.9m). Overall safety was controllable.

DISCUSSION

High HDAC2patients showed better ORR, DCR, and PFS. In addition, patient with negative PD-L1 and low-level bTMB had better DCR and PFS. This may be related to the epigenetic function of chidamide. However, the sample size was not big enough, so it is necessary to increase sample size to confirm the conclusion.

CONCLUSION

Combination of chidamide and envafolimab showed efficacy signals in certain NSCLC patients. But further identification of beneficial population is necessary for precision treatment.

Biomarker-directed targeted therapy plus durvalumab in advanced non-small-cell lung cancer: a phase 2 umbrella trial

For patients with non-small-cell lung cancer (NSCLC) tumors without currently targetable molecular alterations, standard-of-care treatment is immunotherapy with anti-PD-(L)1 checkpoint inhibitors, alone or with platinum-doublet therapy. However, not all patients derive durable benefit and resistance to immune checkpoint blockade is common. Understanding mechanisms of resistance-which can include defects in DNA damage response and repair pathways, alterations or functional mutations in STK11/LKB1, alterations in antigen-presentation pathways, and immunosuppressive cellular subsets within the tumor microenvironment-and developing effective therapies to overcome them, remains an unmet need. Here the phase 2 umbrella HUDSON study evaluated rational combination regimens for advanced NSCLC following failure of anti-PD-(L)1-containing immunotherapy and platinum-doublet therapy. A total of 268 patients received durvalumab (anti-PD-L1 monoclonal antibody)-ceralasertib (ATR kinase inhibitor), durvalumab-olaparib (PARP inhibitor), durvalumab-danvatirsen (STAT3 antisense oligonucleotide) or durvalumab-oleclumab (anti-CD73 monoclonal antibody). Greatest clinical benefit was observed with durvalumab-ceralasertib; objective response rate (primary outcome) was 13.9% (11/79) versus 2.6% (5/189) with other regimens, pooled, median progression-free survival (secondary outcome) was 5.8 (80% confidence interval 4.6-7.4) versus 2.7 (1.8-2.8) months, and median overall survival (secondary outcome) was 17.4 (14.1-20.3) versus 9.4 (7.5-10.6) months. Benefit with durvalumab-ceralasertib was consistent across known immunotherapy-refractory subgroups. In ATM-altered patients hypothesized to harbor vulnerability to ATR inhibition, objective response rate was 26.1% (6/23) and median progression-free survival/median overall survival were 8.4/22.8 months. Durvalumab-ceralasertib safety/tolerability profile was manageable. Biomarker analyses suggested that anti-PD-L1/ATR inhibition induced immune changes that reinvigorated antitumor immunity. Durvalumab-ceralasertib is under further investigation in immunotherapy-refractory NSCLC.ClinicalTrials.gov identifier: NCT03334617.

CD57-positive CD8 + T cells define the response to anti-programmed cell death protein-1 immunotherapy in patients with advanced non-small cell lung cancer

Immune checkpoint inhibitors have transformed the treatment landscape of non-small cell lung cancer (NSCLC). However, accurately identifying patients who will benefit from immunotherapy remains a challenge. This study aimed to discover potential biomarkers for predicting immunotherapy response in NSCLC patients. Single-cell mass cytometry (CyTOF) was utilized to analyze immune cell subsets in peripheral blood mononuclear cells (PBMCs) obtained from NSCLC patients before and 12 weeks after single-agent immunotherapy. The CyTOF findings were subsequently validated using flow cytometry and multiplex immunohistochemistry/immunofluorescence in PBMCs and tumor tissues, respectively. RNA sequencing (RNA-seq) was performed to elucidate the underlying mechanisms. In the CyTOF cohort (n = 20), a high frequency of CD57+CD8+ T cells in PBMCs was associated with durable clinical benefit from immunotherapy in NSCLC patients (p = 0.034). This association was further confirmed in an independent cohort using flow cytometry (n = 27; p < 0.001), with a determined cutoff value of 12.85%. The cutoff value was subsequently validated in another independent cohort (AUC = 0.733). We also confirmed the CyTOF findings in pre-treatment formalin-fixed and paraffin-embedded tissues (n = 90; p < 0.001). RNA-seq analysis revealed 475 differentially expressed genes (DEGs) between CD57+CD8+ T cells and CD57-CD8+ T cells, with functional analysis identifying DEGs significantly enriched in immune-related signaling pathways. This study highlights CD57+CD8+ T cells as a promising biomarker for predicting immunotherapy success in NSCLC patients.

Modified Bushen Yiqi formula enhances antitumor immunity by reducing the chemotactic recruitment of M2-TAMs and PMN-MDSCs in Lewis lung cancer-bearing mice

ETHNOPHARMACOLOGICAL RELEVANCE

Modified Bushen Yiqi formula (MBYF) has shown efficacy as an herbal combination therapy with anti-PD-1 for lung cancer patients. However, the underlying mechanisms of its antitumor effects in lung cancer remain unclear.

AIM OF THE STUDY

This study aims to observe the antitumor effect of MBYF and explore its synergistic mechanism in combination with anti-PD-1 based on the tumor immune microenvironment.

MATERIALS AND METHODS

The antitumor effect of MBYF was assessed in Lewis Lung Cancer (LLC)-bearing mice by evaluating tumor volume, weight, and histology in five groups (model control, MBYF 8.125 g/kg, MBYF 16.25 g/kg, MBYF 32.50 g/kg, anti-PD-1). Mechanisms were analyzed using pharmacology network and tumor RNA-sequencing. Tumor-infiltrating immune cells were measured by flow cytometry and immunohistochemistry. Targets and pathways were validated through qRT-PCR, immuno-histochemistry, and western blotting. The synergistic effect of MBYF in combination with anti-PD-1 was validated in three groups (model control, anti-PD-1, anti-PD-1+MBYF 16.25 g/kg).

RESULTS

MBYF inhibited tumor growth and proliferation and demonstrated safety for the heart, liver, and kidney. Mechanistically, MBYF downregulated tumor proliferation by suppressing the expression of CCND1, CTNNB1, EGFR, and the PI3K-AKT/STAT3/ERK pathway. Furthermore, MBYF may upregulated the antitumor immunity (CD4+T cells, active CD8+ T cells, and NK cells) by reducing the infiltration of M2-TAMs and PMN-MDSCs. MBYF may inhibit the recruitment of M2-TAMs by downregulating the CCR5-CCLs axis and PMN-MDSCs by the CXCR2-CXCLs axis. In vivo study confirmed that MBYF enhanced the antitumor effect of anti-PD-1 therapy.

CONCLUSION

Modified Bushen Yiqi formula enhances antitumor immunity in the treatment of lung cancer by reducing the chemotactic recruitment of M2-TAMs and PMN-MDSCs, suggesting its potential as an adjunct therapy to enhance anti-PD-1 responses and improve treatment outcomes. Further research and clinical studies are needed to validate and expand upon these promising findings.

FUT3 facilitates glucose metabolism of lung adenocarcinoma via activation of NF-κB pathway

OBJECTIVE

Fucosyltransferases (FUTs) molecules have been identified to be involved in carcinogenesis of malignant tumors. Nevertheless, the biological function of fucosyltransferases-3 (FUT3) in lung adenocarcinoma (LUAD) malignant phenotype remains unclear. Herein, we investigated the association between FUT3 and LUAD pathological process.

METHODS

Immunochemistry, RT-qPCR and western blot assays were conducted to evaluate the expression of FUT3 in LUAD and corresponding adjacent tissues. The prognostic value of FUT3 was assessed via Kaplan‑Meier plotter database. The biological process and potential mechanism of FUT3 in LUAD were conducted via GSEA. Additionally, immunofluorescence and metabolite activity detection were performed to determine the potential role of FUT3 in LUAD glucose metabolism. The active biomarkers associated with NF-κB signaling pathway were detected via western blot. Subcutaneous tumor model was conducted to analyze the effect of FUT3 on tumorigenesis of LUAD.

RESULTS

FUT3 was remarkably upregulated in LUAD tissues compared with adjacent tissues from individuals. FUT3 overexpression may predict poor prognosis of LUAD patients. Knockdown of FUT3 significantly inhibited tumor proliferation, migration and glucometabolic alteration in LUAD cells. Moreover, GSEA demonstrated that elevated FUT3 was positively related to NF-κB signaling pathway. Additionally, in vitro and in vivo assays also indicated that downregulation of FUT3 resulted in the suppression of oncogenesis and glucose metabolism via inactivation of NF-κB pathway.

CONCLUSION

Our findings demonstrated that FUT3 was involved in glucometabolic process and tumorigenesis of LUAD via NF-κB signaling pathway. FUT3 may be an optimal target for diagnosis and treatment of LUAD patients.

Prognostic utility of body composition parameters based on computed tomography analysis of advanced non-small cell lung cancer treated with immune checkpoint inhibitors

OBJECTIVE

The purpose of this study was to evaluate the prognostic impact of body composition parameters based on computed tomography (CT) in patients with non-small cell lung cancer (NSCLC) who received ICI treatment.

METHODS

This retrospective study analyzed the data from advanced NSCLC patients treated with ICI therapy between 2013 and 2019. We included patients with NSCLC who underwent baseline CT scans. The exclusion criteria included patients who received three or more lines of chemotherapy, those with insufficient clinical information, or those without treatment response evaluation.

RESULTS

A total of 136 patients were enrolled. Among the volumetric body composition parameters, patients in the highest quartiles (Q2-4) of the visceral fat index (VFI) exhibited a higher response rate to ICI therapy than those in the lowest quartile (Q1) of VFI (Q1 vs. Q2-4: 18.2% vs. 43.1%, p = 0.012). Patients with a VFI in Q2-4 had significantly prolonged progression-free survival (PFS) and overall survival (OS) (PFS, Q1 vs. Q2-4: 3.0 months vs. 6.4 months, p = 0.043; OS, Q1 vs. Q2-4: 5.6 months vs. 16.3 months, p = 0.004). Kaplan-Meier analysis based on the VFI and visceral fat Hounsfield unit (HU) revealed that patients with VFI in Q1 and HU in Q2-4 had the worst prognosis.

CONCLUSIONS

Visceral fat volume is significantly associated with treatment outcomes in ICI-treated patients with NSCLC. Moreover, fat quality may impact the treatment outcomes. This finding underscores the potential significance of both fat compartments and fat quality as prognostic indicators.

CRITICAL RELEVANCE STATEMENT

Visceral fat volume is significantly associated with treatment outcomes in ICI-treated patients with non-small cell lung cancer. Moreover, fat quality may impact the treatment outcomes. This finding underscores the potential significance of both fat compartments and fat quality as prognostic indicators.

KEY POINTS

• We found that visceral fat volume positively correlated with treatment response and survival in patients with non-small cell lung cancer receiving immune checkpoint inhibitors. • Additionally, a trend toward a negative correlation between visceral fat attenuation and survival was observed. • The findings highlight the prognostic utility of fat compartments and fat quality.

First-in-Human, Phase I Dose-Escalation and Dose-Expansion Study of Trophoblast Cell-Surface Antigen 2-Directed Antibody-Drug Conjugate Datopotamab Deruxtecan in Non-Small-Cell Lung Cancer: TROPION-PanTumor01

PURPOSE

This first-in-human, dose-escalation and dose-expansion study evaluated the safety, tolerability, and antitumor activity of datopotamab deruxtecan (Dato-DXd), a novel trophoblast cell-surface antigen 2 (TROP2)-directed antibody-drug conjugate in solid tumors, including advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Adults with locally advanced/metastatic NSCLC received 0.27-10 mg/kg Dato-DXd once every 3 weeks during escalation or 4, 6, or 8 mg/kg Dato-DXd once every 3 weeks during expansion. Primary end points were safety and tolerability. Secondary end points included objective response rate (ORR), survival, and pharmacokinetics.

RESULTS

Two hundred ten patients received Dato-DXd, including 180 in the 4-8 mg/kg dose-expansion cohorts. This population had a median of three prior lines of therapy. The maximum tolerated dose was 8 mg/kg once every 3 weeks; the recommended dose for further development was 6 mg/kg once every 3 weeks. In patients receiving 6 mg/kg (n = 50), median duration on study, including follow-up, and median exposure were 13.3 and 3.5 months, respectively. The most frequent any-grade treatment-emergent adverse events (TEAEs) were nausea (64%), stomatitis (60%), and alopecia (42%). Grade ≥3 TEAEs and treatment-related AEs occurred in 54% and 26% of patients, respectively. Interstitial lung disease adjudicated as drug-related (two grade 2 and one grade 4) occurred in three of 50 patients (6%). The ORR was 26% (95% CI, 14.6 to 40.3), and median duration of response was 10.5 months; median progression-free survival and overall survival were 6.9 months (95% CI, 2.7 to 8.8 months) and 11.4 months (95% CI, 7.1 to 20.6 months), respectively. Responses occurred regardless of TROP2 expression.

CONCLUSION

Promising antitumor activity and a manageable safety profile were seen with Dato-DXd in heavily pretreated patients with advanced NSCLC. Further investigation as first-line combination therapy in advanced NSCLC and as monotherapy in the second-line setting and beyond is ongoing.

The therapeutic potential of exosomes in lung cancer

BACKGROUND

Lung cancer (LC) is one of the most common malignancies globally. Besides early detection and surgical resection, there is currently no effective curative treatment for metastatic advanced LC. Exosomes are endogenous nano-extracellular vesicles produced by somatic cells that play an important role in the development and maintenance of normal physiology. Exosomes can carry proteins, peptides, lipids, nucleic acids, and various small molecules for intra- and intercellular material transport or signal transduction. LC cells can maintain their survival, proliferation, migration, invasion, and metastasis, by producing or interacting with exosomes. Basic and clinical data also show that exosomes can be used to suppress LC cell proliferation and viability, induce apoptosis, and enhance treatment sensitivity. Due to the high stability and target specificity, good biocompatibility, and low immunogenicity of exosomes, they show promise as vehicles of LC therapy.

CONCLUSION

We have written this comprehensive review to communicate the LC treatment potential of exosomes and their underlying molecular mechanisms. We found that overall, LC cells can exchange substances or crosstalk with themselves or various other cells in the surrounding TME or distant organs through exosomes. Through this, they can modulate their survival, proliferation, stemness, migration, and invasion, EMT, metastasis, and apoptotic resistance.

Predicting lung adenocarcinoma prognosis, immune escape, and pharmacomic profile from arginine and proline-related genes

Lung adenocarcinoma (LUAD) is a highly heterogeneous disease that ranks first in morbidity and mortality. Abnormal arginine metabolism is associated with inflammatory lung disease and may influence alterations in the tumor immune microenvironment. However, the potential role of arginine and proline metabolic patterns and immune molecular markers in LUAD is unclear. Gene expression, somatic mutations, and clinicopathological information of LUAD were downloaded from The Cancer Genome Atlas (TCGA) database. Univariate Cox regression analysis was performed to identify metabolic genes associated with overall survival (OS). Unsupervised clustering divided the sample into two subtypes with different metabolic and immunological profiles. Gene set enrichment analysis (GESA) and gene set variation analysis (GSVA) were used to analyze the underlying biological processes of the two subtypes. Drug sensitivity between subtypes was also predicted; then prognostic features were developed by multivariate Cox regression analysis. In addition, validation was obtained in the GSE68465, and GSE50081 dataset. Then, gene expression, and clinical characterization of hub genes CPS1 and SMS were performed; finally, in vitro validation experiments for knockdown of SMS were performed in LUAD cell lines. In this study, we first identified 12 arginine and proline-related genes (APRGs) significantly associated with OS and characterized the clinicopathological features and tumor microenvironmental landscape of two different subtypes. Then, we established an arginine and proline metabolism-related scoring system and identified two hub genes highly associated with prognosis, namely CPS1, and SMS. In addition, we performed CCK8, transwell, and other functional experiments on SMS to obtain consistent results. Our comprehensive analysis revealed the potential molecular features and clinical applications of APRGs in LUAD. A model based on 2 APRGs can accurately predict survival outcomes in LUAD, improve our understanding of APRGs in LUAD, and pave a new pathway to guide risk stratification and treatment strategy development for LUAD patients.

The progresses of relevant factors on the efficacy of immune checkpoint inhibitors in the non-small cell lung cancer patients

Lung cancer has the highest mortality rate of all cancers worldwide. Although immune checkpoint inhibitor (ICI)-based therapy can improve the survival of patients with lung cancer, its efficacy is affected by many factors. Therefore, it is necessary to identify factors that affect the efficacy of ICI-based treatment and establish a model for predicting drug response and resistance before and during treatment for individualized and accurate treatment of patients. This review summarizes the clinical and biological factors related to ICI-based treatment of non-small cell lung cancer (NSCLC) and the recent research progress of predictive models for assessing ICI efficacy.

Bayesian hierarchical quantile regression with application to characterizing the immune architecture of lung cancer

The successful development and implementation of precision immuno-oncology therapies requires a deeper understanding of the immune architecture at a patient level. T-cell receptor (TCR) repertoire sequencing is a relatively new technology that enables monitoring of T-cells, a subset of immune cells that play a central role in modulating immune response. These immunologic relationships are complex and are governed by various distributional aspects of an individual patient's tumor profile. We propose Bayesian QUANTIle regression for hierarchical COvariates (QUANTICO) that allows simultaneous modeling of hierarchical relationships between multilevel covariates, conducts explicit variable selection, estimates quantile and patient-specific coefficient effects, to induce individualized inference. We show QUANTICO outperforms existing approaches in multiple simulation scenarios. We demonstrate the utility of QUANTICO to investigate the effect of TCR variables on immune response in a cohort of lung cancer patients. At population level, our analyses reveal the mechanistic role of T-cell proportion on the immune cell abundance, with tumor mutation burden as an important factor modulating this relationship. At a patient level, we find several outlier patients based on their quantile-specific coefficient functions, who have higher mutational rates and different smoking history.

Efficacy and safety of immune checkpoint inhibitor rechallenge in non-small cell lung cancer: A systematic review and meta-analysis

BACKGROUND

The aim of the study was to explore the efficacy and safety of immune checkpoint inhibitor (ICI) rechallenge in patients with non-small cell lung cancer (NSCLC).

METHODS

Studies that enrolled NSCLC patients treated with two lines of ICIs were included using four databases. The initial line (1L-) and subsequent lines (2L-) of ICIs were defined as 1L-ICI and 2L-ICI, respectively.

RESULTS

A total of 17 studies involving 2100 patients were included. The pooled objective response rate (ORR), disease control rate (DCR), median progression-free survival (mPFS), and median overall survival (mOS) for 2L-ICIs were 10%, 50%, 3.0 months, and 13.1 months, respectively. The 2L-ICI discontinuation rates caused by toxicities ranged from 0% to 23.5%. Original data were extracted from six studies, covering 89 patients. Patients in whom 1L-ICIs were discontinued following clinical decision (the mPFS of 2L-ICIs was not reach) achieved a more prolonged mPFS of 2L-ICIs than those due to toxicity (5.2 months) and progressive disease (2.1 months) (p < 0.0001). Patients' 1L-PFS for more than 2-years had preferable 2L-ORR (35.0% vs. 9.8%, p = 0.03), 2L-DCR (85.0% vs. 49.0%, p = 0.007), and 2L-mPFS (12.4 vs. 3.0 months, p < 0.0001) than those less than 1-year. Patients administered the same drugs achieved a significantly prolonged mPFS compared with the remaining patients (5.4 vs. 2.3 months, p = 0.0004), and those who did not accept antitumor treatments during the intervals of two lines of ICIs achieved a prolonged mPFS compared to those patients who did accept treatments (7.6 vs. 1.9 months, p < 0.0001).

CONCLUSIONS

ICI rechallenge is a useful therapeutic strategy for NSCLC patients, especially suitable for those who achieve long-term tumor remission for more than 2-years under 1L-ICIs.

Plasma D-dimer and interleukin-6 are associated with treatment response and progression-free survival in advanced NSCLC patients on anti-PD-1 therapy

BACKGROUND/AIMS

Response to therapy after using immune checkpoint inhibitors (ICIs) is unpredictable due to significant interindividual variation in efficacy among advanced non-small cell lung cancer (NSCLC) patients. The current study centered on the identification of perivascular blood biomarkers for predicting the effectiveness of anti-programmed cell death protein 1 (anti-PD-1) treatment and progression-free survival (PFS) in advanced NSCLC patients, that could be applied to help determine how to change treatment plans therapeutic regimens for optimizing clinical benefits.

METHODS

A comprehensive review of 100 advanced or recurrent NSCLC patients receiving anti-PD-1 therapy (Camrelizumab, pembrolizumab, sintilimab, or nivolumab) was conducted between January 2018 and April 2021 in Tianjin Medical University Cancer Hospital. The cutoff values of D-dimer were selected from rom our previous study, and interleukin-6 (IL-6) was divided according to the median. Using computed tomography, tumor response was evaluated in accordance with the Response Assessment Criteria in Solid Tumors, version 1.1.

RESULTS

High IL-6 level in advanced NSCLC patients was predictive of low efficacy and a short PFS duration after anti-PD-1 therapy. An increased D-dimer value of 981 ng/mL was significantly predictive of disease progression in NSCLC patients treated with anti-PD-1 and high D-dimer expression predictive of short duration of PFS. Further studies on the correlation between IL-6, D-dimer, and anti-PD-1 efficacy in NSCLC patients stratified by gender revealed that D-dimer and IL-6 levels were significantly associated with the risk of PFS in male patients.

CONCLUSIONS

High IL-6 content in peripheral blood in patients with advanced non-small cell lung cancer may contribute to poor anti-PD-1 efficacy and short duration of PFS through inducing alterations in the tumor microenvironment. D-dimer in peripheral blood is predictive of hyperfibrinolysis and contributes to the release of tumor-driven specific factors, leading to poor effects of anti-PD-1 therapy.

Comprehensive Review: Unveiling the Pro-Oncogenic Roles of IL-1ß and PD-1/PD-L1 in NSCLC Development and Targeting Their Pathways for Clinical Management

In the past decade, targeted therapies for solid tumors, including non-small cell lung cancer (NSCLC), have advanced significantly, offering tailored treatment options for patients. However, individuals without targetable mutations pose a clinical challenge, as they may not respond to standard treatments like immune-checkpoint inhibitors (ICIs) and novel targeted therapies. While the mechanism of action of ICIs seems promising, the lack of a robust response limits their widespread use. Although the expression levels of programmed death ligand 1 (PD-L1) on tumor cells are used to predict ICI response, identifying new biomarkers, particularly those associated with the tumor microenvironment (TME), is crucial to address this unmet need. Recently, inflammatory cytokines such as interleukin-1 beta (IL-1β) have emerged as a key area of focus and hold significant potential implications for future clinical practice. Combinatorial approaches of IL-1β inhibitors and ICIs may provide a potential therapeutic modality for NSCLC patients without targetable mutations. Recent advancements in our understanding of the intricate relationship between inflammation and oncogenesis, particularly involving the IL-1β/PD-1/PD-L1 pathway, have shed light on their application in lung cancer development and clinical outcomes of patients. Targeting these pathways in cancers like NSCLC holds immense potential to revolutionize cancer treatment, particularly for patients lacking targetable genetic mutations. However, despite these promising prospects, there remain certain aspects of this pathway that require further investigation, particularly regarding treatment resistance. Therefore, the objective of this review is to delve into the role of IL-1β in NSCLC, its participation in inflammatory pathways, and its intricate crosstalk with the PD-1/PD-L1 pathway. Additionally, we aim to explore the potential of IL-1β as a therapeutic target for NSCLC treatment.

Emerging agents for the treatment of advanced or metastatic NSCLC without actionable genomic alterations with progression on first-line therapy

INTRODUCTION

Lung cancer is the second most common cancer in the world and the leading cause of cancer-related mortality. Immune checkpoint inhibitors (ICIs), as monotherapy or in combination with platinum-based chemotherapy, have emerged as the standard of care first-line treatment option for patients with advanced non-small cell lung cancer (NSCLC) without actionable genomic alterations (AGAs). Despite significant improvements in patient outcomes with these regimens, primary or acquired resistance is common and most patients develop disease progression, resulting in poor survival.

AREAS COVERED

We review the current treatments commonly used for NSCLC without AGAs in the first-line and subsequent settings and describe the unmet needs for these patients in the second-line setting, including a lack of standard definitions for primary and required resistance, and few effective treatment options for patients who develop progression of their disease on first-line therapy. We describe key mechanisms of resistance to ICIs and emerging therapies that are being investigated for patients who develop progression on ICIs and platinum-based chemotherapy.

EXPERT OPINION

Emerging agents in development have a variety of different mechanisms of action and will likely change standard of care for second-line therapy and beyond for patients with NSCLC without AGAs in the future.

TROPION-Lung08: phase III study of datopotamab deruxtecan plus pembrolizumab as first-line therapy for advanced NSCLC

Pembrolizumab monotherapy is a standard first-line treatment for PD-L1-high advanced non-small-cell lung cancer (NSCLC) without actionable genomic alterations (AGA). However, few patients experience long-term disease control, highlighting the need for more effective therapies. Datopotamab deruxtecan (Dato-DXd), a novel trophoblast cell-surface antigen 2-directed antibody-drug conjugate, showed encouraging safety and antitumor activity with pembrolizumab in advanced NSCLC. We describe the rationale and design of TROPION-Lung08, a phase III study evaluating safety and efficacy of first-line Dato-DXd plus pembrolizumab versus pembrolizumab monotherapy in patients with advanced/metastatic NSCLC without AGAs and with PD-L1 tumor proportion score ≥50%. Primary end points are progression-free survival and overall survival; secondary end points include objective response rate, duration of response, safety and presence of antidrug antibodies. Clinical trial registration: NCT05215340 (ClinicalTrials.gov).

MRTX-500 Phase 2 Trial: Sitravatinib With Nivolumab in Patients With Nonsquamous NSCLC Progressing On or After Checkpoint Inhibitor Therapy or Chemotherapy

INTRODUCTION

Sitravatinib, a receptor tyrosine kinase inhibitor targeting TYRO3, AXL, MERTK receptors, and vascular epithelial growth factor receptor 2, can shift the tumor microenvironment toward an immunostimulatory state. Combining sitravatinib with checkpoint inhibitors (CPIs) may augment antitumor activity.

METHODS

The phase 2 MRTX-500 study evaluated sitravatinib (120 mg daily) with nivolumab (every 2 or 4 wk) in patients with advanced nonsquamous NSCLC who progressed on or after previous CPI (CPI-experienced) or chemotherapy (CPI-naive). CPI-experienced patients had a previous clinical benefit (PCB) (complete response, partial response, or stable disease for at least 12 weeks then disease progression) or no PCB (NPCB) from CPI. The primary end point was objective response rate (ORR); secondary objectives included safety and secondary efficacy end points.

RESULTS

Overall, 124 CPI-experienced (NPCB, n = 35; PCB, n = 89) and 32 CPI-naive patients were treated. Investigator-assessed ORR was 11.4% in patients with NPCB, 16.9% with PCB, and 25.0% in CPI-naive. The median progression-free survival was 3.7, 5.6, and 7.1 months with NPCB, PCB, and CPI-naive, respectively; the median overall survival was 7.9 and 13.6 months with NPCB and PCB, respectively (not reached in CPI-naive patients; median follow-up 20.4 mo). Overall, (N = 156), any grade treatment-related adverse events (TRAEs) occurred in 93.6%; grade 3/4 in 58.3%. One grade 5 TRAE occurred in a CPI-naive patient. TRAEs led to treatment discontinuation in 14.1% and dose reduction or interruption in 42.9%. Biomarker analyses supported an immunostimulatory mechanism of action.

CONCLUSIONS

Sitravatinib with nivolumab had a manageable safety profile. Although ORR was not met, this combination exhibited antitumor activity and encouraged survival in CPI-experienced patients with nonsquamous NSCLC.

Factors Predictive of Primary Resistance to Immune Checkpoint Inhibitors in Patients with Advanced Non-Small Cell Lung Cancer

INTRODUCTION

Primary resistance to immune checkpoint inhibitors (ICI) is observed in routine clinical practice. We sought to determine factors predictive of primary resistance to ICI monotherapy, defined by the Society for Immunotherapy of Cancer (SITC) as progression within 6 months of ICI treatment with patients receiving at least 6 weeks of ICI monotherapy, in patients with advanced non-small-cell lung cancer (NSCLC).

METHOD

Patients with stage IV NSCLC treated with at least 6 weeks of single-agent ICI at two tertiary hospitals in Singapore were included. A multivariate logistic regression model was utilised to elucidate factors predictive of primary resistance to ICI.

RESULTS

Of the 108 eligible patients, 59 (54.6%) experienced primary resistance. The majority were male (65.7%), smokers (66.3%), Chinese (79.6%), had adenocarcinoma (76.9%), received Pembrolizumab (55.6%) and received immunotherapy treatment in the later line setting (≥2 lines) (61.1%). Female gender (aOR = 3.16, p = 0.041), a sixth-week neutrophil-to-lymphocyte ratio (NLR) of ≥3) (aOR = 3.454, p = 0.037) and a later line of immunotherapy treatment (≥2 lines) (aOR = 2.676, p = 0.040) were factors predictive of primary resistance to ICI monotherapy in patients with advanced NSCLC.

CONCLUSIONS

Using SITC criteria, an elevated NLR (≥3) at 6 weeks, female gender and a later line of immunotherapy treatment (≥2 lines) were predictive factors of developing primary resistance to ICI monotherapy in patients with advanced NSCLC.

Emerging therapeutic strategies for enhancing sensitivity and countering resistance to programmed cell death protein 1 or programmed death-ligand 1 inhibitors in non-small cell lung cancer

The availability of agents targeting the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint has transformed treatment of advanced and/or metastatic non-small cell lung cancer (NSCLC). However, a substantial proportion of patients treated with these agents do not respond or experience only a brief period of clinical benefit. Even among those whose disease responds, many subsequently experience disease progression. Consequently, novel approaches are needed that enhance antitumor immunity and counter resistance to PD-(L)1 inhibitors, thereby improving and/or prolonging responses and patient outcomes, in both PD-(L)1 inhibitor-sensitive and inhibitor-resistant NSCLC. Mechanisms contributing to sensitivity and/or resistance to PD-(L)1 inhibitors in NSCLC include upregulation of other immune checkpoints and/or the presence of an immunosuppressive tumor microenvironment, which represent potential targets for new therapies. This review explores novel therapeutic regimens under investigation for enhancing responses to PD-(L)1 inhibitors and countering resistance, and summarizes the latest clinical evidence in NSCLC.

SAFFRON-103: a phase 1b study of the safety and efficacy of sitravatinib combined with tislelizumab in patients with locally advanced or metastatic non-small cell lung cancer

BACKGROUND

Some patients with locally advanced/metastatic non-small cell lung cancer (NSCLC) respond poorly to anti-programmed cell death protein 1 (PD-1)/anti-programmed death-ligand 1 (PD-L1) treatments. Combination with other agents may improve the outcomes. This open-label, multicenter, phase 1b trial investigated the combination of sitravatinib, a spectrum-selective tyrosine kinase inhibitor, plus anti-PD-1 antibody tislelizumab.

METHODS

Patients with locally advanced/metastatic NSCLC were enrolled (Cohorts A, B, F, H, and I; N=22-24 per cohort). Cohorts A and F included patients previously treated with systemic therapy, with anti-PD-(L)1-resistant/refractory non-squamous (cohort A) or squamous (cohort F) disease. Cohort B included patients previously treated with systemic therapy, with anti-PD-(L)1-naïve non-squamous disease. Cohorts H and I included patients without prior systemic therapy for metastatic disease, no prior anti-PD-(L)1/immunotherapy, with PD-L1-positive non-squamous (cohort H) or squamous (cohort I) histology. Patients received sitravatinib 120 mg orally one time per day plus tislelizumab 200 mg intravenously every 3 weeks, until study withdrawal, disease progression, unacceptable toxicity, or death. The primary endpoint was safety/tolerability among all treated patients (N=122). Secondary endpoints included investigator-assessed tumor responses and progression-free survival (PFS).

RESULTS

Median follow-up was 10.9 months (range: 0.4-30.6). Treatment-related adverse events (TRAEs) occurred in 98.4% of the patients, with ≥Grade 3 TRAEs in 51.6%. TRAEs led to discontinuation of either drug in 23.0% of the patients. Overall response rate was 8.7% (n/N: 2/23; 95% CI: 1.1% to 28.0%), 18.2% (4/22; 95% CI: 5.2% to 40.3%), 23.8% (5/21; 95% CI: 8.2% to 47.2%), 57.1% (12/21; 95% CI: 34.0% to 78.2%), and 30.4% (7/23; 95% CI: 13.2% to 52.9%) in cohorts A, F, B, H, and I, respectively. Median duration of response was not reached in cohort A and ranged from 6.9 to 17.9 months across other cohorts. Disease control was achieved in 78.3-90.9% of the patients. Median PFS ranged from 4.2 (cohort A) to 11.1 months (cohort H).

CONCLUSIONS

In patients with locally advanced/metastatic NSCLC, sitravatinib plus tislelizumab was tolerable for most patients, with no new safety signals and overall safety profiles consistent with known profiles of these agents. Objective responses were observed in all cohorts, including in patients naïve to systemic and anti-PD-(L)1 treatments, or with anti-PD-(L)1 resistant/refractory disease. Results support further investigation in selected NSCLC populations.

TRIAL REGISTRATION NUMBER

NCT03666143.

Mechanisms of drug resistance to immune checkpoint inhibitors in non-small cell lung cancer

Immune checkpoint inhibitors (ICIs) in the form of anti-CTLA-4 and anti-PD-1/PD-L1 have become the frontier of cancer treatment and successfully prolonged the survival of patients with advanced non-small cell lung cancer (NSCLC). But the efficacy varies among different patient population, and many patients succumb to disease progression after an initial response to ICIs. Current research highlights the heterogeneity of resistance mechanisms and the critical role of tumor microenvironment (TME) in ICIs resistance. In this review, we discussed the mechanisms of ICIs resistance in NSCLC, and proposed strategies to overcome resistance.

Resistance to immune checkpoint inhibitors in advanced lung cancer: Clinical characteristics, potential prognostic factors and next strategy

Background

Immune checkpoint inhibitors (ICIs) have shown unprecedented clinical benefit in cancer immunotherapy and are rapidly transforming the practice of advanced lung cancer. However, resistance routinely develops in patients treated with ICIs. We conducted this retrospective study to provide an overview on clinical characteristics of ICI resistance, optimal treatment beyond disease progression after prior exposure to immunotherapy, as well as potential prognostic factors of such resistance.

Methods

190 patients diagnosed with unresectable lung cancer who received at least one administration of an anti-programmed cell death 1 (PD-1)/anti-programmed cell death-ligand 1(PD-L1) at any treatment line at Zhongshan Hospital Fudan University between Sep 2017 and December 2019 were enrolled in our study. Overall survival (OS) and progression-free survival (PFS) were analyzed. Levels of plasma cytokines were evaluated for the prognostic value of ICI resistance.

Results

We found that EGFR/ALK/ROS1 mutation and receiving ICI treatment as second-line therapy were risk factors associated with ICI resistance. Patients with bone metastasis at baseline had a significantly shorter PFS1 time when receiving initial ICI treatment. Whether or not patients with oligo-progression received local treatment seemed to have no significant effect on PFS2 time. Systemic therapies including chemotherapy and anti-angiogenic therapy rather than continued immunotherapy beyond ICI resistance had significant effect on PFS2 time. TNF, IL-6 and IL-8 were significantly elevated when ICI resistance. Lower plasma TNF level and higher plasma IL-8 level seemed to be significantly associated with ICI resistance. A nomogram was established to prognosis the clinical outcome of patients treated with ICIs.

Conclusion

Patients with EGFR/ALK/ROS1 mutation, or those receiving ICI treatment as second-line therapy had higher risk of ICI resistance. Patients with bone metastasis had poor prognosis during immunotherapy. For those patients with oligo-progression after ICI resistance, combination with local treatment did not lead to a significantly longer PFS2 time. Chemotherapy and anti-angiogenic therapy rather than continued immunotherapy beyond ICI resistance had significant effect on PFS2 time. Levels of plasma cytokines including TNF, IL-6 and IL-8 were associated with ICI resistance.

New insights into epigenetic regulation of resistance to PD-1/PD-L1 blockade cancer immunotherapy: mechanisms and therapeutic opportunities

Programmed cell death protein 1(PD-1) is a type of immune-inhibitory checkpoint protein, which delivers inhibitory signals to cytotoxic T cells by binding to the programmed death ligand-1 (PD-L1) displayed on the surface of cancer cells. Antibodies blocking PD-1/PD-L1 interaction have been extensively used in treatment of human malignancies and have achieved promising outcomes in recent years. However, gradual development of resistance to PD-1/PD-L1 blockade has decreased the effectiveness of this immunotherapy in cancer patients. The underlying epigenetic mechanisms need to be elucidated for application of novel strategies overcoming this immunotherapy resistance. Epigenetic aberrations contribute to cancerogenesis by promoting different hallmarks of cancer. Moreover, these alterations may lead to therapy resistance, thereby leading to poor prognosis. Recently, the epigenetic regulatory drugs have been shown to decrease the resistance to PD-1/PD-L1 inhibitors in certain cancer patients. Inhibitors of the non-coding RNAs, DNA methyltransferases, and histone deacetylases combined with PD-1/PD-L1 inhibitors have shown considerable therapeutic efficacy against carcinomas as well as blood cancers. Importantly, DNA methylation-mediated epigenetic silencing can inhibit antigen processing and presentation, which promotes cancerogenesis and aggravates resistance to PD-1/PD-L1 blockade immunotherapy. These observations altogether suggest that the combination of the epigenetic regulatory drugs with PD-1/PD-L1 inhibitors may present potential solution to the resistance caused by monotherapy of PD-1/PD-L1 immunotherapy.

Common strategies for effective immunotherapy of gastroesophageal cancers using immune checkpoint inhibitors

Gastroesophageal cancers (GECs) are very prevalent around the world and rank as the second cause of all cancer-related deaths in men and women and demonstrate a very poor prognosis. Currently, the treatment options for these malignancies are very limited and the response rates are also very low. Recently, immune checkpoint inhibitors (ICIs) have been proposed for immunotherapy of GECs; although preliminary results obtained from the clinical trials of ICIs in GECs were promising, they have shown to be effective only in a few subsets of patients who had a previous immune response to the tumor. In order to maximize the efficacy of ICIs in GECs, as well as identify the patients who will likely benefit from ICIs, several predictive biomarkers, such as Programmed death-ligand 1 (PD-L1) have been developed and evaluated. Since the single ICI therapies resulted in poor treatment response, several clinical studies began to explore various combinations of one or two ICIs with other anti-cancer treatment approaches, including chemotherapy, radiotherapy, and anti-angiogenesis therapy. These combinations demonstrated a more effective response among the ICIs-responsive patients and even in some instances sensitized the non-responsive individuals. This review is aimed to summarize the efforts made so far for improving the effectiveness of ICIs in the treatment of patients with GECs. Furthermore, multiple aspects of translational medicine such as available biomarkers and interactions between tumor and the immune system, as well as clinical aspects regarding the combination therapies and results of clinical trials will be discussed.

Discovery of Biomarkers of Resistance to Immune Checkpoint Blockade in NSCLC Using High-Plex Digital Spatial Profiling

INTRODUCTION

Despite the clinical efficacy of immune checkpoint inhibitors (ICIs) in NSCLC, only approximately 20% of patients remain disease-free at 5 years. Here, we use digital spatial profiling to find candidate biomarker proteins associated with ICI resistance.

METHODS

Pretreatment samples from 56 patients with NSCLC treated with ICI were analyzed using the NanoString GeoMx digital spatial profiling method. A panel of 71 photocleavable oligonucleotide-labeled primary antibodies was used for protein detection in four molecular compartments (tumor, leukocytes, macrophages, and immune stroma). Promising candidates were orthogonally validated with quantitative immunofluorescence. Available pretreatment samples from 39 additional patients with NSCLC who received ICI and 236 non-ICI-treated patients with operable NSCLC were analyzed to provide independent cohort validation.

RESULTS

Biomarker discovery using the protein-based molecular compartmentalization strategy allows 284 protein variables to be assessed for association with ICI resistance by univariate analysis using continuous log-scaled data. Of the 71 candidate protein biomarkers, CD66b in the CD45+CD68 molecular compartment (immune stroma) predicted significantly shorter overall survival (OS) (hazard ratio [HR] 1.31, p = 0.016) and was chosen for validation. Orthogonal validation by quantitative immunofluorescence illustrated that CD66b was associated with resistance to ICI therapy but not prognostic for poor outcomes in untreated NSCLC (discovery cohort [OS HR 2.49, p = 0.026], validation cohort [OS HR 2.05, p = 0.046], non-ICI-treated cohort [OS HR 1.67, p = 0.06]).

CONCLUSIONS

Using the technique, we have discovered that CD66b expression is indicative of resistance to ICI therapy in NSCLC. Given that CD66b identifies neutrophils, further studies are warranted to characterize the role of neutrophils in ICI resistance.

Combination Approaches to Target PD-1 Signaling in Cancer

Cancer remains the second leading cause of death in the US, accounting for 25% of all deaths nationwide. Immunotherapy techniques bolster the immune cells' ability to target malignant cancer cells and have brought immense improvements in the field of cancer treatments. One important inhibitory protein in T cells, programmed cell death protein 1 (PD-1), has become an invaluable target for cancer immunotherapy. While anti-PD-1 antibody therapy is extremely successful in some patients, in others it fails or even causes further complications, including cancer hyper-progression and immune-related adverse events. Along with countless translational studies of the PD-1 signaling pathway, there are currently close to 5,000 clinical trials for antibodies against PD-1 and its ligand, PD-L1, around 80% of which investigate combinations with other therapies. Nevertheless, more work is needed to better understand the PD-1 signaling pathway and to facilitate new and improved evidence-based combination strategies. In this work, we consolidate recent discoveries of PD-1 signaling mediators and their therapeutic potential in combination with anti-PD-1/PD-L1 agents. We focus on the phosphatases SHP2 and PTPN2; the kinases ITK, VRK2, GSK-3, and CDK4/6; and the signaling adaptor protein PAG. We discuss their biology both in cancer cells and T cells, with a focus on their role in relation to PD-1 to determine their potential in therapeutic combinations. The literature discussed here was obtained from a search of the published literature and ClinicalTrials.gov with the following key terms: checkpoint inhibition, cancer immunotherapy, PD-1, PD-L1, SHP2, PTPN2, ITK, VRK2, CDK4/6, GSK-3, and PAG. Together, we find that all of these proteins are logical and promising targets for combination therapy, and that with a deeper mechanistic understanding they have potential to improve the response rate and decrease adverse events when thoughtfully used in combination with checkpoint inhibitors.

Addressing CPI resistance in NSCLC: targeting TAM receptors to modulate the tumor microenvironment and future prospects

Lung cancer remains a leading cause of cancer death worldwide, with non-small-cell lung cancer (NSCLC) accounting for the majority of cases. Immune checkpoint inhibitors (CPIs), including those targeting programmed cell death protein-1 and its ligand (PD-1/PD-L1), have revolutionized the treatment landscape for various cancers. Notably, PD-1/PD-L1 inhibitor-based regimens now form the standard first-line therapy for metastatic NSCLC, substantially improving patients' overall survival. Despite the progress made using CPI-based therapies in advanced NSCLC, most patients experience disease progression after an initial response due to resistance. Given the currently limited therapeutic options available for second-line and beyond settings in NSCLC, new treatment approaches are needed to improve long-term survival in these patients. Thus, CPI resistance is an emerging concept in cancer treatment and an active area of clinical research.Among the key mechanisms of CPI resistance is the immunosuppressive tumor microenvironment (TME). Effective CPI therapy is based on shifting immune responses against cancer cells, therefore, manipulating the immunosuppressive TME comprises an important strategy to combat CPI resistance. Several aspects of the TME can contribute to treatment resistance in NSCLC, including through the activation of Tyro3, Axl, MerTK (TAM) receptors which are essential pleiotropic regulators of immune homeostasis. Their roles include negatively modulating the immune response, therefore ectopic expression of TAM receptors in the context of cancer can contribute to the immunosuppressive, protumorigenic TME. Furthermore, TAM receptors represent important candidates to simultaneously target both tumor cells and immune cells in the TME. Clinical development of TAM receptor inhibitors (TAM RIs) is increasingly focused on their ability to rescue the antitumor immune response, thereby shifting the immunosuppressive TME to an immunostimulatory TME. There is a strong biological rationale for combining TAM RIs with a CPI to overcome resistance and improve long-term clinical responses in NSCLC. Combinatorial clinical trials of TAM RIs with CPIs are underway with encouraging preliminary results. This review outlines the key mechanisms of CPI resistance, including the role of the immunosuppressive TME, and discusses the rationale for targeting TAM receptors as a novel, promising therapeutic strategy to overcome CPI resistance in NSCLC.

Signal pathways and precision therapy of small-cell lung cancer

Small-cell lung cancer (SCLC) encounters up 15% of all lung cancers, and is characterized by a high rate of proliferation, a tendency for early metastasis and generally poor prognosis. Most of the patients present with distant metastatic disease at the time of clinical diagnosis, and only one-third are eligible for potentially curative treatment. Recently, investigations into the genomic make-up of SCLC show extensive chromosomal rearrangements, high mutational burden and loss-of-function mutations of several tumor suppressor genes. Although the clinical development of new treatments for SCLC has been limited in recent years, a better understanding of oncogenic driver alterations has found potential novel targets that might be suitable for therapeutic approaches. Currently, there are six types of potential treatable signaling pathways in SCLC, including signaling pathways targeting the cell cycle and DNA repair, tumor development, cell metabolism, epigenetic regulation, tumor immunity and angiogenesis. At this point, however, there is still a lack of understanding of their role in SCLC tumor biology and the promotion of cancer growth. Importantly optimizing drug targets, improving drug pharmacology, and identifying potential biomarkers are the main focus and further efforts are required to recognize patients who benefit most from novel therapies in development. This review will focus on the current learning on the signaling pathways, the status of immunotherapy, and targeted therapy in SCLC.

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.

TAK-676: A Novel Stimulator of Interferon Genes (STING) Agonist Promoting Durable IFN-dependent Antitumor Immunity in Preclinical Studies

Oncology therapies targeting the immune system have improved patient outcomes across a wide range of tumor types, but resistance due to an inadequate T-cell response in a suppressive tumor microenvironment (TME) remains a significant problem. New therapies that activate an innate immune response and relieve this suppression may be beneficial to overcome this hurdle. TAK-676 is a synthetic novel stimulator of interferon genes (STING) agonist designed for intravenous administration. Here we demonstrate that TAK-676 dose-dependently triggers activation of the STING signaling pathway and activation of type I interferons. Furthermore, we show that TAK-676 is a highly potent modulator of both the innate and adaptive immune system and that it promotes the activation of dendritic cells, natural killer cells, and T cells in preclinical models. In syngeneic murine tumor models in vivo, TAK-676 induces dose-dependent cytokine responses and increases the activation and proliferation of immune cells within the TME and tumor-associated lymphoid tissue. We also demonstrate that TAK-676 dosing results in significant STING-dependent antitumor activity, including complete regressions and durable memory T-cell immunity. We show that TAK-676 is well tolerated, exhibits dose-proportional pharmacokinetics in plasma, and exhibits higher exposure in tumor. The intravenous administration of TAK-676 provides potential treatment benefit in a broad range of tumor types. Further study of TAK-676 in first-in-human phase I trials is ongoing.

Significance

TAK-676 is a novel systemic STING agonist demonstrating robust activation of innate and adaptive immune activity resulting in durable antitumor responses within multiple syngeneic tumor models. Clinical investigation of TAK-676 is ongoing.

Harnessing Natural Killer Cells in Non-Small Cell Lung Cancer

Lung cancer is the leading cause of cancer-related deaths worldwide. There are two main subtypes: small cell lung cancer (SCLC), and non-small cell lung cancer (NSCLC). NSCLC accounts for 85% of lung cancer diagnoses. Early lung cancer very often has no specific symptoms, and many patients present with late stage disease. Despite the various treatments currently available, many patients experience tumor relapse or develop therapeutic resistance, highlighting the need for more effective therapies. The development of immunotherapies has revolutionized the cancer treatment landscape by enhancing the body’s own immune system to fight cancer. Natural killer (NK) cells are crucial anti-tumor immune cells, and their exclusion from the tumor microenvironment is associated with poorer survival. It is well established that NK cell frequencies and functions are impaired in NSCLC; thus, placing NK cell-based immunotherapies as a desirable therapeutic concept for this malignancy. Immunotherapies such as checkpoint inhibitors are transforming outcomes for NSCLC. This review explores the current treatment landscape for NSCLC, the role of NK cells and their dysfunction in the cancer setting, the advancement of NK cell therapies, and their future utility in NSCLC.

Comprehensive analysis of a TNF family based-signature in diffuse gliomas with regard to prognosis and immune significance

BACKGROUND

Several studies have shown that members of the tumor necrosis factor (TNF) family play an important role in cancer immunoregulation, and trials targeting these molecules are already underway. Our study aimed to integrate and analyze the expression patterns and clinical significance of TNF family-related genes in gliomas.

METHODS

A total of 1749 gliomas from 4 datasets were enrolled in our study, including the Cancer Genome Atlas (TCGA) dataset as the training cohort and the other three datasets (CGGA, GSE16011, and Rembrandt) as validation cohorts. Clinical information, RNA expression data, and genomic profile were collected for analysis. We screened the signature gene set by Cox proportional hazards modelling. We evaluated the prognostic value of the signature by Kaplan-Meier analysis and timeROC curve. Gene Ontology (GO) and Gene set enrichment analysis (GSEA) analysis were performed for functional annotation. CIBERSORT algorithm and inflammatory metagenes were used to reveal immune characteristics.

RESULTS

In gliomas, the expression of most TNF family members was positively correlated. Univariate analysis showed that most TNF family members were related to the overall survival of patients. Then through the LASSO regression model, we developed a TNF family-based signature, which was related to clinical, molecular, and genetic characteristics of patients with glioma. Moreover, the signature was found to be an independent prognostic marker through survival curve analysis and Cox regression analysis. Furthermore, a nomogram prognostic model was constructed to predict individual survival rates at 1, 3 and 5 years. Functional annotation analysis revealed that the immune and inflammatory response pathways were enriched in the high-risk group. Immunological analysis showed the immunosuppressive status in the high-risk group.

CONCLUSIONS

We developed a TNF family-based signature to predict the prognosis of patients with glioma. Video abstract.

A Combination of Biomarkers Predict Response to Immune Checkpoint Blockade Therapy in Non-Small Cell Lung Cancer

Immune checkpoint blockade (ICB) therapy has provided clinical benefits for patients with advanced non-small-cell lung cancer (NSCLC), but the majority still do not respond. Although a few biomarkers of ICB treatment response have been developed, the predictive power of these biomarkers showed substantial variation across datasets. Therefore, predicting response to ICB therapy remains a challenge. Here, we provided a concise combinatorial strategy for predicting ICB therapy response and constructed the ICB treatment signature (ITS) in lung cancer. The prediction performance of ITS has been validated in an independent ICB treatment cohort of NSCLC, where patients with higher ITS score were significantly associated with longer progression-free survival and better response. And ITS score was more powerful than traditional biomarkers, such as TMB and PD-L1, in predicting the ICB treatment response in NSCLC. In addition, ITS scores still had predictive effects in other cancer data sets, showing strong scalability and robustness. Further research showed that a high ITS score represented comprehensive immune activation characteristics including activated immune cell infiltration, increased mutation load, and TCR diversity. In conclusion, our practice suggested that the combination of biomarkers will lead to a better prediction of ICB treatment prognosis, and the ITS score will provide NSCLC patients with better ICB treatment decisions.

Untargeted Lipidomics of Non-Small Cell Lung Carcinoma Demonstrates Differentially Abundant Lipid Classes in Cancer vs. Non-Cancer Tissue

Lung cancer remains the leading cause of cancer death worldwide and non-small cell lung carcinoma (NSCLC) represents 85% of newly diagnosed lung cancers. In this study, we utilized our untargeted assignment tool Small Molecule Isotope Resolved Formula Enumerator (SMIRFE) and ultra-high-resolution Fourier transform mass spectrometry to examine lipid profile differences between paired cancerous and non-cancerous lung tissue samples from 86 patients with suspected stage I or IIA primary NSCLC. Correlation and co-occurrence analysis revealed significant lipid profile differences between cancer and non-cancer samples. Further analysis of machine-learned lipid categories for the differentially abundant molecular formulas identified a high abundance sterol, high abundance and high m/z sphingolipid, and low abundance glycerophospholipid metabolic phenotype across the NSCLC samples. At the class level, higher abundances of sterol esters and lower abundances of cardiolipins were observed suggesting altered stearoyl-CoA desaturase 1 (SCD1) or acetyl-CoA acetyltransferase (ACAT1) activity and altered human cardiolipin synthase 1 or lysocardiolipin acyltransferase activity respectively, the latter of which is known to confer apoptotic resistance. The presence of a shared metabolic phenotype across a variety of genetically distinct NSCLC subtypes suggests that this phenotype is necessary for NSCLC development and may result from multiple distinct genetic lesions. Thus, targeting the shared affected pathways may be beneficial for a variety of genetically distinct NSCLC subtypes.

The Role of Immunotherapy in the Treatment of Advanced Cervical Cancer: Current Status and Future Perspectives

Cervical cancer remains one of the most common cancers in women around the world however therapeutic options in the advanced and recurrent setting are limited. Immune checkpoint inhibitors (ICI) have been considered an attractive option given the viral etiology of cervical cancer although the majority of patients do not benefit from their use. This review summarises current knowledge and use of immune checkpoint blockade in cervical cancer as well as discussing the challenges faced in their clinical application, namely, the role of biomarker-driven ICI use, potential mechanisms of resistance, strategies to overcome such resistance and additional immunotherapy options beyond ICI.

hsa_circ_0003222 accelerates stemness and progression of non-small cell lung cancer by sponging miR-527

The relationship between circular RNA (circRNA) and cancer stem cells (CSCs) is uncertain. We have investigated the combined influence of CSCs, circRNA (hsa_circ_0003222), and immune checkpoint inhibitors in NSCLC progression and therapy resistance. We constructed lung CSCs (LCSCs; PC9 and A549). The effects of hsa_circ_0003222 in vitro were determined by cell counting, colony and sphere formation, and Transwell assays. A tumor xenograft model of metastasis and orthotopic model were built for in vivo analysis. We found that hsa_circ_0003222 was highly expressed in NSCLC tissues and LCSCs. Higher levels of hsa_circ_0003222 were associated with the stage, metastasis, and survival rate of patients with NSCLC. Reduced levels of hsa_circ_0003222 decreased tumor cell proliferation, migration, invasion, stemness-like properties, and chemoresistance. The silencing of hsa_circ_0003222 was found to downregulate PHF21B expression and its downstream, β-catenin by relieving the sponging effect of miR-527. Moreover, silencing hsa_circ_0003222 alleviated NSCLC resistance to anti-programmed cell death-ligand 1 (PD-L1)-based therapy in vivo. Our data demonstrate the significant role of hsa_circ_0003222 in NSCLC cell stemness-like properties. The manipulation of circRNAs in combination with anti-PD-L1 therapy may alleviate NSCLC stemness and progression.

Lung adenocarcinoma with ERBB2 exon 20 insertions: Comutations and immunogenomic features related to chemoimmunotherapy

BACKGROUND

The genomic mutation and immune feature landscape of ERBB2 exon 20 insertion (ERBB2-ex20ins)-driven non-small cell lung cancer and the features associated with the response to chemoimmunotherapy are currently unknown.

METHODS

The genomic landscape of ERBB2-ex20ins lung adenocarcinoma (LUAD) patients was characterized by next-generation sequencing (NGS) of 1021 cancer genes. The clinical outcomes of chemoimmunotherapy were evaluated among 13 patients with stage IV ERBB2-ex20ins LUAD, and potential biomarkers of the response to chemoimmunotherapy were explored using NGS and T cell receptor sequencing.

RESULTS

Among 8247 LUAD patients, 207 (2.5%) had ERBB2-ex20ins, of whom 181 (87.4%) harbored more than one comutation. The most common comutations were in TP53. Patients with ERBB2-ex20ins had a low tumor mutational burden (TMB; median, 4.2 mutations/Mb), and most (66.7%) were PD-L1 negative. Thirteen of the 207 patients received chemoimmunotherapy, for whom the objective response rate, disease control rate, and median progression-free survival were 31%, 77%, and 8.0 months, respectively. Responders exhibited a higher TMB and a trend toward lower clonality in tumors compared with nonresponders (p = 0.0067 and p = 0.085, respectively). A high TMB combined with mutations in DNA damage repair pathways and SWI/SNF chromatin remodeling complexes was associated with a benefit from chemoimmunotherapy.

CONCLUSIONS

The efficacy and outcome of chemoimmunotherapy were encouraging among ERBB2-ex20ins LUAD patients, who were characterized by low TMB and negative PD-L1 expression. The combination of TMB and comutations is a potential biomarker to identify patients who will benefit from chemoimmunotherapy.

[Immunotherapy for Lung Cancer: Mechanisms of Resistance and Response Strategy]

Inhibition of immune checkpoints is at the forefront of immunotherapy for lung cancer. However, a high percentage of lung cancer patients do not respond to these immunotherpy or their responses are transient, indicating the existence of immune resistance. Emerging evidence suggested that the interactions between cancer cells and immune system were continuous and dynamic. Here, we review how a range of cancer-cell-autonomous characteristics, tumor-microenvironment factors, and host-related influences account for heterogenous responses. Furthermore, with the identification of new targets of immunotherapy and development of immune-based combination therapy, we elucidate the methods might useful to overcome resistance.

The progress and challenge of anti-PD-1/PD-L1 immunotherapy in treating non-small cell lung cancer

The use of programmed cell-death protein 1 (PD-1)/programmed cell-death ligand 1 (PD-L1) inhibitors is the standard therapy for the first-line or second-line treatment of patients with non-small-cell lung cancer (NSCLC). In contrast to current traditional treatments such as chemotherapy or radiotherapy, anti-PD-1 and anti-PD-L1 treatments can directly attenuate tumour-mediated exhaustion and effectively modulate the host anti-tumour immune response in vivo. In addition, compared with traditional therapy, PD-1/PD-L1 inhibitor monotherapy can significantly prolong survival without obvious side effects in the treatment of advanced NSCLC. Ideally, several biomarkers could be used to monitor the safety and effectiveness of anti-PD-1 and anti-PD-L1 treatments; however, the current lack of optimal prognostic markers remains a widespread limitation and challenge for further clinical applications, as does the possibility of immune-related adverse events and drug resistance. In this review, we aimed to summarise the latest progress in anti-PD-1/anti-PD-L1 treatment of advanced NSCLC, worldwide, including in China. An exploration of underlying biomarker identification and future challenges will be discussed in this article to facilitate translational studies in cancer immunotherapy.

Next Generation Sequencing-Based Profiling of Cell Free DNA in Patients with Advanced Non-Small Cell Lung Cancer: Advantages and Pitfalls

Lung cancer (LC) is the main cause of death for cancer worldwide and non-small cell lung cancer (NSCLC) represents the most common histology. The discovery of genomic alterations in driver genes that offer the possibility of therapeutic intervention has completely changed the approach to the diagnosis and therapy of advanced NSCLC patients, and tumor molecular profiling has become mandatory for the choice of the most appropriate therapeutic strategy. However, in approximately 30% of NSCLC patients tumor tissue is inadequate for biomarker analysis. The development of highly sensitive next generation sequencing (NGS) technologies for the analysis of circulating cell-free DNA (cfDNA) is emerging as a valuable alternative to assess tumor molecular landscape in case of tissue unavailability. Additionally, cfDNA NGS testing can better recapitulate NSCLC heterogeneity as compared with tissue testing. In this review we describe the main advantages and limits of using NGS-based cfDNA analysis to guide the therapeutic decision-making process in advanced NSCLC patients, to monitor the response to therapy and to identify mechanisms of resistance early. Therefore, we provide evidence that the implementation of cfDNA NGS testing in clinical research and in the clinical practice can significantly improve precision medicine approaches in patients with advanced NSCLC.

Primary and Acquired Resistance to Immunotherapy in Lung Cancer: Unveiling the Mechanisms Underlying of Immune Checkpoint Blockade Therapy

After several decades without maintained responses or long-term survival of patients with lung cancer, novel therapies have emerged as a hopeful milestone in this research field. The appearance of immunotherapy, especially immune checkpoint inhibitors, has improved both the overall survival and quality of life of patients, many of whom are diagnosed late when classical treatments are ineffective. Despite these unprecedented results, a high percentage of patients do not respond initially to treatment or relapse after a period of response. This is due to resistance mechanisms, which require understanding in order to prevent them and develop strategies to overcome them and increase the number of patients who can benefit from immunotherapy. This review highlights the current knowledge of the mechanisms and their involvement in resistance to immunotherapy in lung cancer, such as aberrations in tumor neoantigen burden, effector T-cell infiltration in the tumor microenvironment (TME), epigenetic modulation, the transcriptional signature, signaling pathways, T-cell exhaustion, and the microbiome. Further research dissecting intratumor and host heterogeneity is necessary to provide answers regarding the immunotherapy response and develop more effective treatments for lung cancer.