MYC activation impairs cell-intrinsic IFNγ signaling and confers resistance to anti-PD1/PD-L1 therapy in lung cancer

Baicalein tethers CD274/PD-L1 for autophagic degradation to boost antitumor immunity

Immune checkpoint inhibitors, especially those targeting CD274/PD-L1yield powerful clinical therapeutic efficacy. Thoughmuch progress has been made in the development of antibody-basedCD274 drugs, chemical compounds applied for CD274degradation remain largely unavailable. Herein,baicalein, a monomer of traditional Chinese medicine, isscreened and validated to target CD274 and induces itsmacroautophagic/autophagic degradation. Moreover, we demonstrate thatCD274 directly interacts with MAP1LC3B (microtubule associatedprotein 1 light chain 3 beta). Intriguingly, baicalein potentiatesCD274-LC3 interaction to facilitate autophagic-lysosomal degradationof CD274. Importantly, targeted CD274. degradation via baicaleininhibits tumor development by boosting T-cell-mediated antitumorimmunity. Thus, we elucidate a critical role of autophagy-lysosomalpathway in mediating CD274 degradation, and conceptually demonstratethat the design of a molecular "glue" that tethers the CD274-LC3interaction is an appealing strategy to develop CD274 inhibitors incancer therapy.Abbreviations: ATTECs: autophagy-tethering compounds; AUTACs: AUtophagy-TArgeting Chimeras; AUTOTACs: AUTOphagy-TArgeting Chimeras; AMPK: adenosine 5'-monophosphate (AMP)-activated protein kinase; BiFC: bimolecular fluorescence complementation; BafA1: bafilomycin A1; CD274/PD-L1/B7-H1: CD274 molecule; CQ: chloroquine; CGAS: cyclic GMP-AMP synthase; DAPI: 4'6-diamino-2-phenylindole; FITC: fluorescein isothiocyanate isomer; GFP: green fluorescent protein; GZMB: granzyme B; IHC: immunohistochemistry; ICB: immune checkpoint blockade; KO: knockout; KD: equilibrium dissociation constant; LYTAC: LYsosome-TArgeting Chimera; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MST: microscale thermophoresis; NFAT: nuclear factor of activated T cells; NFKB/NF-kB: nuclear factor kappa B; NSCLC: non-small-cell lung cancer; PDCD1: programmed cell death 1; PROTACs: PROteolysis TArgeting Chimeras; PRF1: perforin 1; PE: phosphatidylethanolamine; PHA: phytohemagglutinin; PMA: phorbol 12-myristate 13-acetate; STAT: signal transducer and activator of transcription; SPR: surface plasmon resonance; TILs: tumor-infiltrating lymphocyte; TME: tumor microenvironment.

Current status of KRAS G12C inhibitors in NSCLC and the potential for combination with anti-PD-(L)1 therapy: a systematic review

In recent years, precision medicine for non-small cell lung cancer (NSCLC) has made significant strides, particularly with advancements in diagnostic and therapeutic technologies. Targeted 7therapies and Anti-PD-(L)1 Therapies have emerged as vital treatment options, yet KRAS mutations, especially KRAS G12C, have been historically difficult to address. Due to the unique activation mechanism of KRAS G12C has led to the development of specific inhibitors, such as AMG 510 and MRTX849, which show promising therapeutic potential. However, results from the CodeBreaK 200 Phase III trial indicated that AMG 510 did not significantly improve overall survival compared to docetaxel. Resistance after prolonged use of KRAS G12C inhibitors continues to pose a challenge, prompting interest in new drugs and combination strategies. KRAS mutations can impair tumor-infiltrating T cell function and create an immunosuppressive tumor microenvironment, making the combination of KRAS G12C inhibitors with anti-PD-(L)1 therapies particularly appealing. Preliminary data suggest these combinations may enhance both survival and quality of life, though safety concerns remain a barrier. Ongoing research is crucial to refine treatment regimens and identify suitable patient populations. This review focuses on the development of KRAS G12C inhibitors in monotherapy and combination therapies for NSCLC, discussing major clinical trials and future research directions.

Potential role of lactylation in intrinsic immune pathways in lung cancer

Lung cancer, one of the most lethal malignancies, has seen its therapeutic strategies become a focal point of significant scientific attention. Intrinsic immune signaling pathways play crucial roles in anti-tumor immunity but face clinical application challenges despite promising preclinical outcomes. Lactylation, an emerging research focus, may influences lung cancer progression by modulating the functions of histones and non-histone proteins. Recent findings have suggested that lactylation regulates key intrinsic immune molecules, including cGAS-STING, TLR, and RIG-I, thereby impacting interferon expression. However, the precise mechanisms by which lactylation governs intrinsic immune signaling in lung cancer remain unclear. This review presents a comprehensive and systematic analysis of the relationship between lactylation and intrinsic immune signaling pathways in lung cancer and emphasizes the innovative perspective of linking lactylation-mediated epigenetic modifications with immune regulation. By thoroughly examining current research findings, this review uncovers potential regulatory mechanisms and highlights the therapeutic implications of targeting lactylation in lung cancer. Future investigations into the intricate interactions between lactylation and intrinsic immunity are anticipated to unveil novel therapeutic targets and strategies, potentially improving patient survival outcomes.

Therapeutic Applications of Programmed Death Ligand 1 Inhibitors in Small Cell Lung Cancer

Background: Small cell lung cancer (SCLC) is an aggressive cancer with rapid progression, limited treatment success, and high relapse rates. Chemotherapy and radiation are standard treatments but often result in chemoresistance. PD-L1 inhibitors have gained attention for their role in enhancing tumor immunity. Methods: This review summarizes clinical trials involving PD-L1 inhibitors, such as atezolizumab, durvalumab, pembrolizumab, and nivolumab, in SCLC treatment. Key trials include IMpower133, CASPIAN, KEYNOTE-604, and CheckMate 331, focusing on survival outcomes and treatment efficacy. Results: Studies such as IMpower133 and CASPIAN demonstrate improved overall survival when PD-L1 inhibitors were added to platinum-based chemotherapy. However, outcomes in trials such as KEYNOTE-604 and CheckMate 331 varied, showing the need for refined patient selection. Adverse events (AEs) associated with these treatments were also noted. PD-L1 inhibitors offer promise in SCLC treatment, but efficacy varies across trials and patient groups. Future research should focus on better patient selection and overcoming resistance mechanisms. Addressing immune-related AEs is essential for optimizing treatment strategies.

Multi-omics analysis reveals the sensitivity of immunotherapy for unresectable non-small cell lung cancer

Background

To construct a prediction model consisting of metabolites and proteins in peripheral blood plasma to predict whether patients with unresectable stage III and IV non-small cell lung cancer can benefit from immunotherapy before it is administered.

Methods

Peripheral blood plasma was collected from unresectable stage III and IV non-small cell lung cancer patients who were negative for driver mutations before receiving immunotherapy. Then we classified samples according to the follow-up results after two courses of immunotherapy and non-targeted metabolomics and proteomics analyses were performed to select different metabolites and proteins. Finally, potential biomarkers were picked out by applying machine learning methods including random forest and stepwise regression and prediction models were constructed by logistic regression.

Results

The presence of metabolites and proteins in peripheral blood plasma was causally associated with both non-small cell lung cancer and PD-L1/PD-1 expression levels. A total of 2 differential metabolites including 5-sulfooxymethylfurfural and Anthranilic acid and 2 differential proteins including Immunoglobulin heavy variable 1-45 and Microfibril-associated glycoprotein 4 were selected as reliable biomarkers. The area under the curve (AUC) of the prediction model built on clinical risks was merely 0.659. The AUC of metabolomics prediction model was 0.977 and the AUC of proteomics was 0.875 while the AUC of the integrative-omics prediction model was 0.955.

Conclusions

Metabolic and protein biomarkers in peripheral blood both have high efficacy and reliability in the prediction of immunotherapy sensitivity in unresectable stage III and IV non-small cell lung cancer, but validation in larger population-based cohorts is still needed.

Subtype-specific human endogenous retrovirus K102 envelope protein is a novel serum immunosuppressive biomarker of cancer

Immune dysfunction is one of the hallmarks of cancer and plays critical roles in immunotherapy resistance, but there is no serum biomarker that can be used to evaluate immune-dysfunction status of cancer patients. Here, we identified subtype-specific human endogenous retrovirus K102 envelope (HERV-K102-Env) with immunosuppressive activity in circulating blood as a novel serum immunosuppressive biomarker of cancer. We first generated monoclonal antibodies against K102-Env with high sensitivity and specificity, and we developed an ELISA assay to detect serum K102-Env. We then investigated whether K102-Env and K108-Env proteins are present in circulating blood of cancer patients. We found K108-Env proteins were present in serum of both patients with cancer and healthy individuals. In contrast, K102-Env markedly increased in patients with PDAC, hepatocellular carcinoma (HCC), and non-small cell lung cancer (NSCLC) compared with healthy controls. The positive rates of K102-Env were 34.00%, 39%, and 28.0% in PDAC, HCC, and NSCLC, respectively, whereas only 5.0% of healthy individuals had marginally increased K102-Env. In the sera of PDAC patients, K102-Env was 36.63-fold higher than that of healthy controls. K102-Env significantly upregulated PD-1/PD-L1 and c-Myc expression levels of T cells. Importantly, serum K102-Env levels correlated well with advanced cancers and tumor biomarkers CA19-9 and AFP. These findings indicate that circulating K102-Env protein is a novel serum biomarker for evaluating immunosuppressive status and disease stage of patients with cancer.

Advances in biomarkers for immunotherapy in small-cell lung cancer

Small-cell lung cancer (SCLC) is a refractory cancer with rapid growth and high aggressiveness. Extensive-stage SCLC is initially sensitive to chemotherapy; however, drug resistance and recurrence occur rapidly, resulting in a poor survival outcome due to lack of subsequently efficient therapy. The emergence of immune checkpoint inhibitors (ICIs) generated a new landscape of SCLC treatment and significantly prolonged the survival of patients. However, the unselected immunotherapy restrains both beneficiary population and responsive period in SCLC compared to the other tumors. The complex tumor origin, high heterogeneity, and immunosuppressive microenvironment may disturb the value of conventional biomarkers in SCLC including programmed cell death 1 ligand 1 and tumor mutation burden. Transcriptional regulator-based subtypes of SCLC are current research hotspot, revealing that Y (I) subtype can benefit from ICIs. Additionally, molecules related to immune microenvironment, immunogenicity, epigenetics, and SCLC itself also indicated the therapeutic benefits of ICIs, becoming potential predictive biomarkers. In this review, we discussed the advances of biomarkers for prediction and prognosis of immunotherapy, promising directions in the future, and provide reference and options for precision immunotherapy and survival improvement in patients with SCLC.

Recent advances in immunotherapy for small cell lung cancer

PURPOSE OF REVIEW

This review aims to provide an overview of recent advances in immunotherapy for small cell lung cancer (SCLC), with a focus on the current status of immune checkpoint inhibitors (ICIs), novel combination strategies, and key biomarkers.

RECENT FINDINGS

The integration of ICIs into standard chemotherapy has established them as the first-line treatment for extensive-stage SCLC (ES-SCLC). The ADRIATIC trial further demonstrated the efficacy of ICI maintenance therapy in limited-stage SCLC. Additionally, combining radiotherapy with ICIs has shown promising synergistic effects, including the abscopal and radscopal effects. Ongoing investigations into the combination of ICIs with targeted therapies, such as antiangiogenic agents and DNA damage response inhibitors, have yielded encouraging preliminary results. Notably, the novel therapeutic agent tarlatamab, the first bispecific DLL3-directed CD3 T-cell engager, has recently received FDA approval for second-line treatment of ES-SCLC. Advances in omics technologies have shed light on the intra-tumor and inter-tumor heterogeneity of SCLC, leading to the identification of new molecular subtypes and biomarkers, thereby paving the way for precision medicine.

SUMMARY

Despite the improved outcomes associated with immunotherapy in SCLC, the overall clinical benefit remains modest. Further preclinical and clinical studies are essential to identify optimal treatment regimens and enhance therapeutic efficacy.

Astragaloside IV augments anti-PD-1 therapy to suppress tumor growth in lung cancer by remodeling the tumor microenvironment

Programmed cell death protein-1 (PD-1) inhibitors are increasingly utilized in the treatment of lung cancer (LC). Combination therapy has recently gained popularity in treating LC. This study aimed to assess the efficacy of combining Astragaloside IV (AS-IV) and anti-PD-1 in LC. C57BL/6J mice were subcutaneously injected with Lewis lung carcinoma (LLC) cells. After 3 weeks, the animals were sacrificed, and the tumors were harvested for analysis. Ki-67 immuno-labeling and TUNEL assay were used for evaluating cell proliferation and apoptosis in tumor tissues. In addition, anti-cleaved caspase 3 was used for immunolabelling of apoptotic cells. Immune cell infiltration (macrophages and T cells) and gene expression in tumor tissues were also investigated by using immunofluorescence staining. Compared to treatment with anti-PD-1 or AS-IV, the combination of AS-IV and anti-PD-1 notably reduced tumor volume and weight of LLC-bearing mice. Additionally, the combination treatment strongly induced the apoptosis and suppressed the proliferation in tumor tissues through inactivating PI3K/Akt and ERK signaling pathways, compared to single treatment group. Moreover, the combination treatment elevated levels of the M1 macrophage marker mCD86, reduced levels of the M2 macrophage marker mCD206, as well as upregulated levels of the T cell activation marker mCD69 in tumor tissues. Collectively, the combination treatment effectively inhibited tumor growth in LLC mice through promoting M1 macrophage polarization and T cell activation. These findings showed that combining AS-IV with anti-PD-1 therapy could be a promising therapeutic approach for LC.

Genomic and molecular alterations associated with primary resistance to immune checkpoint inhibitors

The clinical response to immune checkpoint inhibitors may vary by tumor type and many tumors present with either primary or acquired resistance to immunotherapy. Improved understanding of the molecular and immunologic mechanisms underlying immunotherapy resistance is essential for developing biomarkers and for guiding the optimum approach to selecting treatment regimens and sequencing. This is increasingly important for tumors with primary resistance as effective biomarkers in this setting can guide clinicians about appropriate treatment regimen selection in the first-line setting. Multiple potential biological mechanisms of primary resistance have been proposed but most are yet to be validated in prospective clinical cohorts. Individual biomarkers have poor specificity and sensitivity, and the development of validated and integrated predictive models may guide which patient will benefit from monotherapy versus combination therapy. In this review, we discuss the emerging data identifying the molecular mechanisms of primary resistance to immunotherapy and explore potential therapeutic strategies to target these.

New horizons in the mechanisms and therapeutic strategies for PD-L1 protein degradation in cancer

Programmed death-ligand 1 (PD-L1) has become a crucial focus in cancer immunotherapy considering it is found in many different cells. Cancer cells enhance the suppressive impact of programmed death receptor 1 (PD-1) through elevating PD-L1 expression, which allows them to escape immune detection. Although there have been significant improvements, the effectiveness of anti-PD-1/PD-L1 treatment is still limited to a specific group of patients. An important advancement in cancer immunotherapy involves improving the PD-L1 protein degradation. This review thoroughly examined the processes by which PD-L1 breaks down, including the intracellular pathways of ubiquitination-proteasome and autophagy-lysosome. In addition, the analysis revealed changes that affect PD-L1 stability, such as phosphorylation and glycosylation. The significant consequences of these procedures on cancer immunotherapy and their potential role in innovative therapeutic approaches are emphasised. Our future efforts will focus on understanding new ways in which PD-L1 degradation is controlled and developing innovative treatments, such as proteolysis-targeting chimeras designed specifically to degrade PD-L1. It is crucial to have a thorough comprehension of these pathways in order to improve cancer immunotherapy strategies and hopefully improve therapeutic effectiveness.

TWIST1 is a critical downstream target of the HGF/MET pathway and is required for MET driven acquired resistance in oncogene driven lung cancer

MET amplification/mutations are important targetable oncogenic drivers in NSCLC, however, acquired resistance is inevitable and the majority of patients with targetable MET alterations fail to respond to MET tyrosine kinase inhibitors (TKIs). Furthermore, MET amplification is among the most common mediators of TKI resistance. As such, novel therapies to target MET pathway and overcome MET TKI resistance are clearly needed. Here we show that the epithelial-mesenchymal transition (EMT) transcription factor, TWIST1 is a key downstream mediator of HGF/MET induced resistance through suppression of p27 and targeting TWIST1 can overcome resistance. We found that TWIST1 is overexpressed at the time of TKI resistance in multiple MET-dependent TKI acquired resistance PDX models. We have shown for the first time that MET directly stabilized the TWIST protein leading to TKI resistance and that TWIST1 was required for MET-driven lung tumorigenesis as well as could induce MET TKI resistance when overexpressed. TWIST1 mediated MET TKI resistance through suppression of p27 expression and genetic or pharmacologic inhibition of TWIST1 overcame TKI resistance in vitro and in vivo. Our findings suggest that targeting TWIST1 may be an effective therapeutic strategy to overcome resistance in MET-driven NSCLC as well as in other oncogene driven subtypes in which MET amplification is the resistance mechanism.

CAF-associated genes putatively representing distinct prognosis by in silico landscape of stromal components of colon cancer

Comprehensive understanding prognostic relevance of distinct tumor microenvironment (TME) remained elusive in colon cancer. In this study, we performed in silico analysis of the stromal components of primary colon cancer, with a focus on the markers of cancer-associated fibroblasts (CAF) and tumor-associated endothelia (TAE), as well as immunological infiltrates like tumor-associated myeloid cells (TAMC) and cytotoxic T lymphocytes (CTL). The relevant CAF-associated genes (CAFG)(representing R index = 0.9 or beyond with SPARC) were selected based on stroma specificity (cancer stroma/epithelia, cS/E = 10 or beyond) and expression amounts, which were largely exhibited negative prognostic impacts. CAFG were partially shared with TAE-associated genes (TAEG)(PLAT, ANXA1, and PTRF) and TAMC-associated genes (TAMCG)(NNMT), but not with CTL-associated genes (CTLG). Intriguingly, CAFG were prognostically subclassified in order of fibrosis (representing COL5A2, COL5A1, and COL12A1) followed by exclusive TAEG and TAMCG. Prognosis was independently stratified by CD8A, a CTL marker, in the context of low expression of the strongest negative prognostic CAFG, COL8A1. CTLG were comprehensively identified as IFNG, B2M, and TLR4, in the group of low S/E, representing good prognosis. Our current in silico analysis of the micro-dissected stromal gene signatures with prognostic relevance clarified comprehensive understanding of clinical features of the TME and provides deep insights of the landscape.

Deregulation of interferon-gamma receptor 1 expression and its implications for lung adenocarcinoma progression

Interferon-gamma (IFN-γ) plays a dual role in cancer; it is both a pro- and an antitumorigenic cytokine, depending on the type of cancer. The deregulation of the IFN-γ canonic pathway is associated with several disorders, including vulnerability to viral infections, inflammation, and cancer progression. In particular, the interplay between lung adenocarcinoma (LUAD) and viral infections appears to exist in association with the deregulation of IFN-γ signaling. In this mini-review, we investigated the status of the IFN-γ signaling pathway and the expression level of its components in LUAD. Interestingly, a reduction in IFNGR1 expression seems to be associated with LUAD progression, affecting defenses against viruses such as severe acute respiratory syndrome coronavirus 2. In addition, alterations in the expression of IFNGR1 may inhibit the antiproliferative action of IFN-γ signaling in LUAD.

Biomarkers for Immune Checkpoint Inhibitors in Renal Cell Carcinoma

Immune checkpoint inhibitor (ICI) therapy has revolutionized renal cell carcinoma treatment. Patients previously thought to be palliative now occasionally achieve complete cures from ICI. However, since immunotherapies stimulate the immune system to induce anti-tumor immunity, they often lead to adverse autoimmunity. Furthermore, some patients receive no benefit from ICI, thereby unnecessarily risking adverse events. In many tumor types, PD-L1 expression levels, immune infiltration, and tumor mutation burden predict the response to ICI and help inform clinical decision making to better target ICI to patients most likely to experience benefits. Unfortunately, renal cell carcinoma is an outlier, as these biomarkers fail to discriminate between positive and negative responses to ICI therapy. Emerging biomarkers such as gene expression profiles and the loss of pro-angiogenic proteins VHL and PBRM-1 show promise for identifying renal cell carcinoma cases likely to respond to ICI. This review provides an overview of the mechanistic underpinnings of different biomarkers and describes the theoretical rationale for their use. We discuss the effectiveness of each biomarker in renal cell carcinoma and other cancer types, and we introduce novel biomarkers that have demonstrated some promise in clinical trials.