Tumor PD-L1 Expression Research Articles

PD-L1 is a biomarker of real-world clinical outcomes for anti-CTLA-4 plus anti-PD-1 or anti-PD-1 monotherapy in metastatic melanoma

BackgroundMetastatic melanoma (MM) is commonly treated with a combination of nivolumab and ipilimumab, regardless of tumor PD-L1 expression. MethodsWe conducted a population-based study including all patients with MM (except ocular melanoma) treated in Denmark with first-line combination therapy or anti-PD-1 monotherapy since January 2017. Baseline data including known prognostic characteristics were used in multivariable and propensity-matched score (PMS) analyses to assess progression-free survival (PFS), melanoma-specific survival (MSS), and overall survival (OS) according to PD-L1 expression. ResultsWe identified 1341 eligible patients, with known PD-L1 status for 1081 patients (43% PD-L1 ≥ 1%, 57% PD-L1 < 1%). PD-L1 ≥ 1% was an independent positive prognostic biomarker for survival in the overall cohort (MSS: HR 0.66, CI 0.52–0.83, p < 0.001). In the PMS PD-L1 ≥ 1% cohort, combination therapy showed similar clinical outcomes to monotherapy (PFS: HR 1.41, CI 0.94–2.11, p = 0.101; MSS: HR 1.21, CI 0.70–2.11, p = 0.49; OS: HR 1.17, CI 0.68–2.00, p = 0.567). In contrast, in the PMS PD-L1 < 1% and in the PMS PD-L1 < 1% BRAF WT cohorts, combination therapy improved PFS (respectively with HR 0.70, CI 0.53–0.93, p = 0.013; and HR 0.54, CI 0.37–0.78, p = 0.001), but did not reach statistically significant improvements of MSS (HR 0.72, CI 0.50–1.02, p = 0.065; and HR 0.79, CI 0.51–1.21, p = 0.278) or OS (HR 0.78, CI 0.56–1.08, p = 0.135; and HR 0.81, CI 0.54–1.21, p = 0.305) compared to monotherapy. ConclusionOur findings support previous exploratory analyses of Checkmate-067, highlighting that improved clinical outcomes with combination therapy are not established in unselected patients with high (≥1%) tumor PD-L1 expression.

PD-L1 blockade TAM-dependently potentiates mild photothermal therapy against triple-negative breast cancer

The present work was an endeavor to shed light on how mild photothermia possibly synergizes with immune checkpoint inhibition for tumor therapy. We established mild photothermal heating protocols to generate temperatures of 43 °C and 45 °C in both in vitro and in vivo mouse 4T1 triple-negative breast cancer (TNBC) models using polyglycerol-coated carbon nanohorns (CNH-PG) and 808 nm laser irradiation. Next, we found that 1) CNH-PG-mediated mild photothermia (CNH-PG-mPT) significantly increased expression of the immune checkpoint PD-L1 and type-1 macrophage (M1) markers in the TNBC tumors; 2) CNH-PG-mPT had a lower level of anti-tumor efficacy which was markedly potentiated by BMS-1, a PD-L1 blocker. These observations prompted us to explore the synergetic mechanisms of CNH-PG-mPT and BMS-1 in the context of tumor cell-macrophage interactions mediated by PD-L1 since tumor-associated macrophages (TAMs) are a major source of PD-L1 expression in tumors. In vitro, the study then identified two dimensions where BMS-1 potentiated CNH-PG-mPT. First, CNH-PG-mPT induced PD-L1 upregulation in the tumor cells and showed a low level of cytotoxicity which was potentiated by BMS-1. Second, CNH-PG-mPT skewed TAMs towards an M1-like anti-tumor phenotype with upregulated PD-L1, and BMS-1 bolstered the M1-like phenotype. The synergistic effects of BMS-1 and CNH-PG-mPT both on the tumor cells and TAMs were more pronounced when the two cell populations were in co-culture. Further in vivo study confirmed PD-L1 upregulation both in tumor cells and TAMs in the TNBC tumors following treatment of CNH-PG-mPT. Significantly, TAMs depletion largely abolished the anti-TNBC efficacy of CNH-PG-mPT alone and in synergy with BMS-1. Collectively, our findings reveal PD-L1 upregulation to be a key response of TNBC to mild photothermal stress, which plays a pro-survival role in the tumor cells while also acting as a brake on the M1-like activation of the TAMs. Blockade of mPT‑induced PD‑L1 achieves synergistic anti-TNBC efficacy by taking the intrinsic survival edge off the tumor cells on one hand and taking the brakes off the M1-like TAMs on the other. Our findings reveal a novel way (i.e. mild thermia plus PD-L1 blockade) to modulate the TAMs-tumor cell interaction to instigate a mutiny of the TAMs against their host tumor cells.Graphical

Evaluation of Chelator-to-Antibody Ratio on Development of 89Zr-iPET Tracer for Imaging of PD-L1 Expression on Tumor.

89Zr-iPET has been widely used for preclinical and clinical immunotherapy studies to predict patient stratification or evaluate therapeutic efficacy. In this study, we prepared and evaluated 89Zr-DFO-anti-PD-L1-mAb tracers with varying chelator-to-antibody ratios (CARs), including 89Zr-DFO-anti-PD-L1-mAb_3X (tracer_3X), 89Zr-DFO-anti-PD-L1-mAb_10X (tracer_10X), and 89Zr-DFO-anti-PD-L1-mAb_20X (tracer_20X). The DFO-anti-PD-L1-mAb conjugates with varying CARs were prepared using a random conjugation method and then subjected to quality control. The conjugates were radiolabeled with 89Zr and evaluated in a PD-L1-expressing CT26 tumor-bearing mouse model. Next, iPET imaging, biodistribution, pharmacokinetics, and ex vivo pathological and immunohistochemical examinations were conducted. LC-MS analysis revealed that DFO-anti-PD-L1-mAb conjugates were prepared with CARs ranging from 0.4 to 2.0. Radiochemical purity for all tracer groups was >99% after purification. The specific activity levels of tracer_3X, tracer_10X, and tracer_20X were 2.2 ± 0.6, 8.2 ± 0.6, and 10.5 ± 1.6 μCi/μg, respectively. 89Zr-iPET imaging showed evident tumor uptake in all tracer groups and reached the maximum uptake value at 24 h postinjection (p.i.). Biodistribution data at 168 h p.i. revealed that the tumor-to-liver, tumor-to-muscle, and tumor-to-blood uptake ratios for tracer_3X, tracer_10X, and tracer_20X were 0.46 ± 0.14, 0.58 ± 0.33, and 1.54 ± 0.51; 4.7 ± 1.3, 7.1 ± 3.9, and 14.7 ± 1.1; and 13.1 ± 5.8, 19.4 ± 13.8, and 41.3 ± 10.6, respectively. Significant differences were observed between tracer_3X and tracer_20X in the aforementioned uptake ratios at 168 h p.i. The mean residence time and elimination half-life for tracer_3X, tracer_10X, and tracer_20X were 25.4 ± 4.9, 24.2 ± 6.1, and 25.8 ± 3.3 h and 11.8 ± 0.5, 11.1 ± 0.7, and 11.7 ± 0.6 h, respectively. No statistical differences were found between-tracer in the aforementioned pharmacokinetic parameters. In conclusion, 89Zr-DFO-anti-PD-L1-mAb tracers with a CAR of 1.4-2.0 may be better at imaging PD-L1 expression in tumors than are traditional low-CAR 89Zr-iPET tracers.

The discovery and evaluation of [18F]BMS-986229, a novel macrocyclic peptide PET radioligand for the measurement of PD-L1 expression and in-vivo PD-L1 target engagement.

A same-day PET imaging agent capable of measuring PD-L1 status in tumors is an important tool for optimizing PD-1 and PD-L1 treatments. Herein we describe the discovery and evaluation of a novel, fluorine-18 labeled macrocyclic peptide-based PET ligand for imaging PD-L1. [18F]BMS-986229 was synthesized via copper mediated click-chemistry to yield a PD-L1 PET ligand with picomolar affinity and was tested as an in-vivo tool for assessing PD-L1 expression. Autoradiography showed an 8:1 binding ratio in L2987 (PD-L1 (+)) vs. HT-29 (PD-L1 (-)) tumor tissues, with >90% specific binding. Specific radioligand binding (>90%) was observed in human non-small-cell lung cancer (NSCLC) and cynomolgus monkey spleen tissues. Images of PD-L1 (+) tissues in primates were characterized by high signal-to-noise, with low background signal in non-expressing tissues. PET imaging enabled clear visualization of PD-L1 expression in a murine model in vivo, with 5-fold higher uptake in L2987 (PD-L1 (+)) than in control HT-29 (PD-L1 (-)) tumors. Moreover, this imaging agent was used to measure target engagement of PD-L1 inhibitors (peptide or mAb), in PD-L1 (+) tumors as high as 97%. A novel 18F-labeled macrocyclic peptide radioligand was developed for PET imaging of PD-L1 expressing tissues that demonstrated several advantages within a nonhuman primate model when compared directly to adnectin- or mAb-based ligands. Clinical studies are currently evaluating [18F]BMS-986229 to measure PD-L1 expression in tumors.

Characterization of colorectal cancer by hierarchical clustering analyses of five immune cell markers.

The present study analyzed the expression of five independent immunohistochemical markers, CD4, CD8, CD66b, CD68, and CD163, on immune cells within the colorectal cancer (CRC) tumor microenvironment (TME). Using hierarchical clustering, patients were successfully classified according to significant associations with clinicopathological features and/or survival. Patients with mismatch repair-proficient (pMMR) CRC were categorized into four groups with survival differences (p = 0.0084): CD4Low , CD4High , MΦHigh , and CD8Low . MΦHigh tumors showed significantly higher expression of CD47 (p < 0.0001), a phagocytosis checkpoint molecule. These tumors contained significantly greater numbers of PD-1+ (p < 0.0001), TIM-3+ (p < 0.0001), and SIRPA+ (p < 0.0001) immune cells. Notably, 10% of the patients with pMMR CRC expressed PD-L1 (CD274) on tumor cells with significantly worse survival (p = 0.00064). The Cox proportional hazards model identified MΦ High (hazard ratio [HR] = 2.02, 95%, p = 0.032), CD8Low (HR = 2.45, p = 0.011), and tumor PD-L1 expression (HR = 2.74, p = 0.0061) as potential risk factors. PD-L1-PD-1 and/or CD47-SIRPA axes targeting immune checkpoint therapies might be considered for patients with pMMR CRC according to their tumor cells and tumor immune microenvironment characteristics.

Low glucose availability potentiates the effects of metformin on model T cell activation and exhaustion markers in vitro.

Modulation of immune cell metabolism is one of promising strategies to improve cancer immunotherapies. Metformin is an anti-diabetic drug with potential anti-cancer effects, ranging from normalization of blood glucose and insulin levels, direct anti-proliferative effects on cancer cells to emerging immunomodulatory effects on anti-tumor immunity. Metformin can reduce tumor hypoxia and PD-L1 expression, as well as normalize or improve T cell function and potentiate the effect of immune checkpoint inhibitors, making it a promising adjuvant to immunotherapy of tumors with poor response such as triple negative breast cancer (TNBC). However, although the effects of metformin on cancer cells are glucose-dependent, the role of glucose in modulating its effect on T cells has not been systematically studied. We thus investigated the effect of metformin as a function of glucose level on Jurkat cell and PBMC T cell models in vitro. While low metformin concentrations had little effect on T cell function, high concentration reduced proliferation and IFN-γ secretion in both models and induced a shift in T cell populations from memory to effector subsets. The PD-1/CD69 ratio was improved by high metformin in T cells from PBMC. Low glucose and metformin synergistically reduced PD-1 and CD69 expression and IFN-γ secretion in T cells from PBMC. Low glucose level itself suppressed Jurkat cell function due to their limited metabolic plasticity, but had limited effects on T cells from PBMC apart from reduced proliferation. Conversely, high glucose did not strongly affect either T cell model. Metformin in combination with glycolysis inhibitor 2-deoxy-D-glucose (2DG) reduced PD-1 in Jurkat cells, but also strongly suppressed their function. However, low, physiologically achievable 2DG concentration itself reduced PD-1 while mostly maintaining IL-2 secretion and, interestingly, even strongly increased IFN-γ secretion regardless of glucose level. Overall, glucose metabolism can importantly influence some of the effects of metformin on T cell functionality in the tumor microenvironment. Additionally, we show that 2DG could potentially improve the anti-tumor T cell response.

Perioperative Immunotherapy in Non-Small Cell Lung Cancer.

The standard of care in patients with early-stage non-small cell lung cancer (NSCLC) following surgical resection has been adjuvant chemotherapy for the last two decades, despite modest improvements in survival and high rates of disease recurrence. Numerous clinical trials have reported practice-changing findings demonstrating a benefit in disease-free survival (DFS) or event-free survival (EFS) with perioperative immunotherapy. This has led to several recent regulatory approvals supporting the use of adjuvant immunotherapy or neoadjuvant immuno-chemotherapy in NSCLC, and such therapies are now an integral component of care for early-stage disease. However, in select cases, such as in the presence of certain tumor oncogenes associated with immunotherapy resistance, the use of checkpoint inhibitors in the perioperative setting should generally be avoided. This speaks to the importance of integrating routine tissue-based molecular profiling, that evaluates for tumor oncogene mutations and PD-L1 expression, into our practice when caring for patients with early-stage NSCLC. While an overall survival (OS) advantage has yet to be firmly established from many of the recent studies evaluating perioperative immunotherapy, it is expected that an OS benefit and higher rates of cure will become evident as these data mature, especially among patients with greater levels of tumor PD-L1 expression.

CRISPR screening identifies the deubiquitylase ATXN3 as a PD-L1-positive regulator for tumor immune evasion.

Regulation of tumoral PD-L1 expression is critical to advancing our understanding of tumor immune evasion and the improvement of existing antitumor immunotherapies. Herein, we describe a CRISPR-based screening platform and identified ATXN3 as a positive regulator for PD-L1 transcription. TCGA database analysis revealed a positive correlation between ATXN3 and CD274 in more than 80% of human cancers. ATXN3-induced Pd-l1 transcription was promoted by tumor microenvironmental factors, including the inflammatory cytokine IFN-γ and hypoxia, through protection of their downstream transcription factors IRF1, STAT3, and HIF-2α. Moreover, ATXN3 functioned as a deubiquitinase of the AP-1 transcription factor JunB, indicating that ATNX3 promotes PD-L1 expression through multiple pathways. Targeted deletion of ATXN3 in cancer cells largely abolished IFN-γ- and hypoxia-induced PD-L1 expression and consequently enhanced antitumor immunity in mice, and these effects were partially reversed by PD-L1 reconstitution. Furthermore, tumoral ATXN3 suppression improved the preclinical efficacy of checkpoint blockade antitumor immunotherapy. Importantly, ATXN3 expression was increased in human lung adenocarcinoma and melanoma, and its levels were positively correlated with PD-L1 as well as its transcription factors IRF1 and HIF-2α. Collectively, our study identifies what we believe to be a previously unknown deubiquitinase, ATXN3, as a positive regulator for PD-L1 transcription and provides a rationale for targeting ATXN3 to sensitize checkpoint blockade antitumor immunotherapy.

Durvalumab versus placebo with chemoradiotherapy for locally advanced cervical cancer (CALLA): a randomised, double-blind, phase 3 trial

Concurrent chemoradiotherapy has been the standard of care for locally advanced cervical cancer for over 20 years; however, 30-40% of treated patients have recurrence or progression within 5 years. Immune checkpoint inhibition has improved outcomes for patients with PD-L1 positive metastatic or recurrent cervical cancer. We assessed the benefit of adding durvalumab, a PD-L1 antibody, with and following chemoradiotherapy for locally advanced cervical cancer. The CALLA randomised, double-blind, phase 3 trial included 105 hospitals across 15 countries. Patients aged at least 18 years with previously untreated locally advanced cervical cancer (adenocarcinoma, squamous, or adenosquamous; International Federation of Gynaecology and Obstetrics [FIGO] 2009 stage IB2-IIB lymph node positive, stage ≥III any lymph node status) and WHO or Eastern Cooperative Oncology Group performance status of 0 or 1 were randomly assigned (1:1) through an interactive web response system using a permuted block size of 4 to receive durvalumab (1500 mg intravenously once every 4 weeks) or placebo with and following chemoradiotherapy, for up to 24 cycles. Chemoradiotherapy included 45 Gy external beam radiotherapy at 5 fractions per week concurrent with intravenous cisplatin (40 mg/m2) or carboplatin (area under the concentration-time curve 2) once weekly for 5 weeks, followed by image-guided brachytherapy (high-dose rate, 27·5-30 Gy or low-dose/pulse-dose rate, 35-40 Gy). Randomisation was stratified by disease stage status (FIGO stage and node status) and geographical region. Chemoradiotherapy quality was continuously reviewed. The primary endpoint was progression-free survival, assessed by the investigator using Response Evaluation Criteria in Solid Tumors, version 1.1, in the intention-to-treat population. Safety was assessed in patients who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT03830866. Between Feb 15, 2019, and Dec 10, 2020, 770 women were randomly assigned (385 to durvalumab and 385 to placebo; median age 49 years [IQR 41-57]). Median follow-up was 18·5 months (IQR 13·2-21·5) in the durvalumab group and 18·4 months (13·2-23·7) in the placebo group. At data cutoff, median progression-free survival had not been reached (95% CI not reached-not reached) for either group (HR 0·84; 95% CI 0·65-1·08; p=0·17); 12-month progression-free survival was 76·0% (71·3-80·0) with durvalumab and 73·3% (68·4-77·5) with placebo. The most frequently reported grade 3-4 adverse events in both groups were anaemia (76 [20%] of 385 in the durvalumab group vs 56 [15%] of 384 in the placebo group) and decreased white blood cells (39 [10%] vs 49 [13%]). Serious adverse events occurred for 106 (28%) patients who received durvalumab and 89 (23%) patients who received placebo. There were five treatment-related deaths in the durvalumab group (one case each of urinary tract infection, blood loss anaemia, and pulmonary embolism related to chemoradiotherapy only; one case of endocrine disorder related to durvalumab only; and one case of sepsis related to both durvalumab and chemoradiotherapy). There was one treatment-related death in the placebo group (pneumonia related to chemoradiotherapy). Durvalumab concurrent with chemoradiotherapy was well tolerated in participants with locally advanced cervical cancer, however it did not significantly improve progression-free survival in a biomarker unselected, all-comers population. Concurrent durvalumab plus chemoradiotherapy warrants further exploration in patients with high tumoral PD-L1 expression. Rigorous monitoring ensured high chemoradiotherapy compliance with advanced technology and allowed patients to receive optimal care. AstraZeneca.

Cancer-associated fibroblasts-derived CXCL12 enhances immune escape of bladder cancer through inhibiting P62-mediated autophagic degradation of PDL1

BackgroundCancer-associated fibroblasts (CAFs), the predominant stromal cell of tumor microenvironment (TME), play an important role in tumor progression and immunoregulation by remodeling extracellular matrix (ECM) and secreting cytokines. However, little is known about the details of the underlying mechanism in bladder cancer.MethodsBioinformatics analysis was performed to analyze the prognostic value of CAFs and CXCL12 using GEO, TCGA and SRA databases. The effects of CXCL12 on bladder cancer progression were investigated through in vitro and in vivo assays. The biological mechanism of the effect of CXCL12 on PDL1 were investigated using western blotting, immunoprecipitation, RT-PCR, immunofluorescence, mass spectrometry, protein stability, and flow cytometry.ResultsThe results demonstrated that CAFs-derived CXCL12 promoted cancer cell migration and invasion and upregulated PDL1. Mechanistically, upon binding to its specific receptor, CXCL12 activated the downstream JAK2/STAT3 pathway and rapidly up-regulated the expression of deubiquitinase CYLD. CYLD deubiquitinated P62 causing P62 accumulation, which in turn inhibited the autophagic degradation of PDL1. In vivo experiments demonstrated that blocking CXCL12 inhibited tumor growth, reduced tumor PDL1 expression and increased immune cell infiltration.ConclusionsThis study revealed a novel mechanism for the role of CXCL12 in P62-mediated PDL1 autophagic regulation. Combined application of CXCL12 receptor blocker and PD1/PDL1 blocker can more effectively inhibit PDL1 expression and enhance antitumor immune response. Targeting CAFs-derived CXCL12 may provide an effective strategy for immunotherapy in bladder cancer.

The mutational pattern of homologous recombination repair genes in urothelial carcinoma and its correlation with immunotherapeutic response.

The mutational pattern of homologous recombination repair (HRR)-associated gene alterations in Chinese urothelial carcinoma (UC) necessitates comprehensive sequencing efforts, and the clinical implications of HRR gene mutations in UC remain to be elucidated. We delineated the mutational landscape of 343 Chinese UC patients from West China Hospital and 822 patients from The Cancer Genome Atlas (TCGA) using next-generation sequencing (NGS). Data from 182 metastatic UC patients from MSK-IMPACT cohort were used to assess the association between HRR mutations and immunotherapy efficacy. Comprehensive transcriptomic analysis was performed to explore the impact of HRR mutations on tumor immune microenvironment. Among Chinese UC patients, 34% harbored HRR gene mutations, with BRCA2, ATM, BRCA1, CDK12, and RAD51C being the most prevalently mutated genes. Mutational signatures contributing to UC differed between patients with and without HRR mutations. Signature 22 for exposure to aristolochic acid was only observed in Chinese UC patients. The presence of HRR mutations was correlated with higher tumor mutational burden, neoantigen burden, and PD-L1 expression. Importantly, patients with HRR mutations exhibited significantly improved prognosis following immunotherapy compared to those without HRR mutations. Our findings provide valuable insights into the genomic landscape of Chinese UC patients and underscore the molecular rationale for utilizing immunotherapy in UC patients with HRR mutations.

Dynamic Up-Regulation of PD-L1 in the Progression of Oral Squamous Cell Carcinoma.

The introduction of immune checkpoint inhibition for recurrent and metastatic head and neck cancer has brought a new treatment option for patients suffering from advanced oral cancers without a chance for curation using surgery or radiotherapy. The application of immune checkpoint inhibitors in most cases is based on the expression levels of PD-L1 in the tumor tissue. To date, there is a lack of data on the dynamic regulation of PD-L1 during disease progression. Therefore, this study aimed to evaluate the expression levels of PD-L1 in a large cohort of patients (n = 222) with oral squamous cell carcinoma including primary and recurrent tumors. Semiautomatic digital pathology scoring was used for the assessment of PD-L1 expression levels in primary and recurrent oral squamous cell carcinoma. Survival analysis was performed to evaluate the prognostic significance of the protein expression at different stages of the disease. We found a significant up-regulation of PD-L1 expression from primary disease to recurrent tumors (mean PD-L1 H-scores: primary tumors: 47.1 ± 31.4; recurrent tumors: 103.5 ± 62.8, p < 0.001). In several cases, a shift from low PD-L1 expression in primary tumors to high PD-L1 expression in recurrent tumors was identified. Multivariate Cox regression analysis did not reveal a significantly higher risk of death (p = 0.078) or recurrence (p = 0.926) in patients with higher PD-L1 expression. Our findings indicate that the exclusive analysis of primary tumor tissue prior to the application of checkpoint blockade may lead to the misjudgment of PD-L1 expression in recurrent tumors.

Distinct Patterns of CD4+ and CD8+ T-Cell Clonal Expansion Enable Broad Clinical Responses to Pembrolizumab + GVD in Patients with Relapsed Hodgkin Lymphoma

Introduction: Classical Hodgkin lymphoma (cHL) is characterized by immune dysregulation, with recurrent amplifications of the 9p24 locus encoding several genes including CD274 (PD-L1), PDCD1LG2 (PD-L2), and JAK2, frequent genetic and epigenetic downregulation of major histocompatibility complex (MHC)-I and (MHC)-II, and a tumor microenvironment (TME) defined by T-cell infiltration and high rates of PD-L1 expression. PD-1 blockade is highly active both as single agent and in combination with chemotherapeutic agents in relapsed/refractory (RR) cHL. However, the mechanism by which PD-1 blockade promotes clinical responses in combination with chemotherapy, and whether the mechanism of action varies based on tumor or TME-specific expression of either MHC or PD-L1 remains unclear. Methods: We previously conducted a phase II study in patients with relapsed or refractory cHL evaluating pembrolizumab in combination with gemcitabine, vinorelbine and liposomal doxorubicin (P-GVD) before proceeding to high-dose therapy and autologous hematopoietic cell transplantation (AHCT) (Moskowitz AJ et al, JCO 2021). Treatment consisted of 2 to 4 cycles of P-GVD followed by AHCT. We performed combined single-cell surface protein identification, RNA sequencing, and (T cell receptor) TCR sequencing using the 10x Genomics Single Cell Immune Profiling Platform on paired C1D1 and C3D1 peripheral blood mononuclear cells (PBMCs) from 23 patients who received P-GVD and 5 control patients with relapsed cHL treated with standard chemotherapy regimens. Expression of MHC-I, MHC-II, and PD-L1 on both Hodgkin Reed Sternberg (HRS) cells and within the TME was assessed by immunohistochemistry. Results:Of 38 evaluable pts, the complete response (CR) rate after 2 or 4 cycles of P-GVD was 95%. After a median follow-up of 40 months (range: 2-56), only 1 pt experienced relapse 23 months after AHCT and another pt died 41 months after AHCT while in remission due to unrelated causes. The estimated 40-month progression-free survival (PFS) is 96% (95% CI: 91-100). CITE-Sequencing of PBMCs across 56 samples from 28 patients revealed predominantly CD4+ T, CD8+ T, NK, and myeloid cells within the peripheral blood, with smaller proportions of hematopoietic progenitors and plasmacytoid dendritic cells. Combined RNA and TCR analysis of the T-cell compartment revealed significant pre-treatment clonal expansion of both CD4+ and CD8+ T-cells exhibiting a cytotoxic phenotype, including expression of GZMH, KLRG1, and CCL5 by CD8+ T-cells and expression of PRF1, NKG7, GNLY, FGFBP2, and GZMH by CD4+ T-cells ( Fig. 1A). Correlation of pre-treatment clonal expansion with tumor-specific MHC status demonstrated that clonal expansion of CD8+ T-cells was more robust in patients whose tumors expressed either MHC-I or MHC-II; conversely, clonal expansion of CD4+ T-cells was most robust in tumors expressing MHC-II but lacking MHC-I, suggesting cytotoxic CD4+ T-cell responses may promote anti-tumor immunity in MHC-I-deficient tumors ( Fig. 1B). Both CD4+ and CD8+ T-cell clonal expansion was highest in patients whose tumors expressed high levels of PD-L1 on stromal cells. Treatment with P-GVD did not result in further clonal expansion of either CD4+ or CD8+ T-cells but did increase expression of cytotoxic genes in pre-treatment expanded CD4+ T-cells, including NKG7 and PLEK, while downregulating negative genes of T-cell function in pre-treatment expanded CD8+ T-cells, including TNFAIP3 and DUSP1, suggesting that P-GVD promotes anti-tumor immunity in cHL by enhancing the cytotoxicity of tumor-reactive expanded CD4+ and CD8+ T-cells. Conclusions: Treatment of relapsed cHL with P- GVD resulted in durable remissions in patients undergoing AHCT. Distinct patterns of peripheral blood T-cell expansion were observed based on MHC-I and MHC-II expression on tumor cells, with CD4+ T-cell clonal expansion uniquely expanding in patients with MHC-I-deficient tumors. Further analysis of the impact of P-GVD on T-cell differentiation and function is ongoing. AcknowledgementT: Supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp &amp; Dohme LLC. The opinions expressed in this paper are those of the authors and do not necessarily represent those of Merck Sharp &amp; Dohme LLC.

Impact of pembrolizumab versus chemotherapy on health-related quality of life in patients with metastatic triple-negative breast cancer: results from the phase 3 randomised KEYNOTE-119 study

In KEYNOTE-119 (ClinicalTrials.gov, NCT02555657), overall survival (primary end-point) was similar between pembrolizumab and chemotherapy in patients with previously treated metastatic triple-negative breast cancer (TNBC), although the pembrolizumab treatment effect increased with tumour PD-L1 expression. We report results of prespecified health-related quality of life (HRQoL) analyses from KEYNOTE-119. Eligible patients were randomised 1:1 to pembrolizumab 200mg Q3W intravenously for up to 35 cycles or treatment of physician's choice per local/country guidelines. Prespecified exploratory end-points were the change from baseline in HRQoL (EORTC QLQ-C30, QLQ-BR23) and to characterise utilities (EQ-5D-3L). Time to deterioration (TTD) was the time from start of treatment to first onset of a ≥10-point worsening from baseline. HRQoL analyses included 187 patients with tumour PD-L1 combined positive score (CPS) ≥10. Changes from baseline at 6 weeks (primary analysis time point) were directionally better with pembrolizumab versus chemotherapy for QLQ-C30 GHS/QoL (between-group difference in least-squares mean scores of 4.21 [95% CI, -1.38 to 9.80]), QLQ-C30 functional scales (physical, role, cognitive, social), QLQ-C30 symptom scales/items (fatigue, nausea/vomiting, dyspnoea, appetite loss), and QLQ-BR23 symptom scales/items (systemic therapy side-effects, upset by hair loss). Median TTD was directionally longer for pembrolizumab versus chemotherapy for QLQ-C30 QHS/QoL (4.3 versus 1.7 months), QLQ-C30 nausea/vomiting (7.7 versus 4.8 months), and QLQ-BR23 systemic therapy side-effects (6.1 versus 3.4 months). Minimal treatment differences were observed for other HRQoL end-points. HRQoL results were consistent with clinical outcomes and appeared to be driven by results for patients with tumour PD-L1 CPS ≥10.

Pembrolizumab With R-CHOP in Previously Untreated DLBCL: Sustained, High Efficacy, and Safety With Long-Term Follow-Up

BackgroundWhile generally ineffective in relapsed diffuse large B cell lymphoma (DLBCL), immune checkpoint inhibitors (ICIs) may hold greater promise in untreated, immunocompetent patients. We previously reported safety and early efficacy of pembrolizumab plus rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (PR-CHOP) in a phase I trial of untreated DLBCL, noting responses in 90% of patients (complete response 77%) and a 2-year progression-free survival (PFS) of 83%. We herein report long-term safety and efficacy at 5-year follow up. Patients and MethodsAdult patients with untreated DLBCL or grade 3b follicular lymphoma, intended to receive 6 cycles of R-CHOP were eligible. Patients (N = 30) were treated with pembrolizumab 200 mg IV and R-CHOP in 21-day cycles for 6 cycles. ResultsAt median follow up of 4.8 years, 5-year PFS was 71% (CI, 54%-94%) and 5-year overall survival was 83% (CI, 71%-98%). Immune-related adverse events (IRAEs) occurred in 7 (23%) patients (10% grade 3/4). Three IRAEs (rash, thyroiditis, rheumatoid arthritis) occurred beyond 3 months of treatment completion. PD-L1 tumor expression was documented in 19 of 23 (83%) tested patients. None of the 19 patients who had any PD-L1 expression have relapsed, whereas 2 out of the 4 patients with no PD-L1 expression have relapsed. ConclusionPR-CHOP has led to durable responses in most patients, with the best outcomes in PD-L1-expressing disease. Furthermore, the safety profile was manageable, with no consistent pattern of late events. These data support ongoing strategies incorporating ICIs in frontline DLBCL therapy and confirmation of predictive biomarkers including tumor PD-L1 expression.

Bis-indole-derived NR4A1 antagonists inhibit colon tumor and splenic growth and T-cell exhaustion

There is evidence that the orphan nuclear receptor 4A1 (NR4A1, Nur77) is overexpressed in exhausted CD8 + T cells and regulates PD-L1 in tumors. This study investigated the effects of potent bis-indole-derived NR4A1 antagonists on reversing T-cell exhaustion and downregulating PD-L1 in colon tumors/cells. NR4A1 antagonists inhibited colon tumor growth and downregulated expression of PD-L1 in mouse colon MC-38-derived tumors and cells. TILs from MC-38 cell-derived colon tumors and splenic lymphocytes exhibited high levels of the T-cell exhaustion markers including PD-1, 2B4, TIM3+ and TIGIT and similar results were observed in the spleen, and these were inhibited by NR4A1 antagonists. In addition, treatment with NR4A1 antagonists induced cytokine activation markers interferon γ, granzyme B and perforin mRNAs and decreased TOX, TOX2 and NFAT in TIL-derived CD8 + T cells. Thus, NR4A1 antagonists decrease NR4A1-dependent pro-oncogenic activity and PD-L1 expression in colon tumors and inhibit NR4A1-dependent T-cell exhaustion in TILs and spleen and represent a novel class of mechanism-based drugs that enhance immune surveillance in tumors.

Correlation of Neuroendocrine Differentiation with a Distinctively Suppressive Immune Microenvironment in Gastric Cancer

Introduction: Neuroendocrine neoplasms (NENs) harbored significantly suppressive tumor immune microenvironments (TIMEs). However, the immunological effects of neuroendocrine differentiation (NED) on non-NENs, such as gastric cancer (GC), were unknown. Methods: Between pure gastric cancer (PGC) and GC-NED, TIME features were scored based on expression data and validated on serial whole-tissue sections of surgical samples, with tertiary lymphoid structures (TLSs) and the extra-TLS zone evaluated independently using multi-marker immunohistochemical staining. Risk analyses of TIME features on tumor behaviors were performed in GC-NED. The universal immunological effects of NED were explored preliminarily in adenocarcinomas arising in other organs. Results: Based on over 11,500 annotated TLSs and 2,700 extra-TLS zones, compared with PGC, GC-NED harbored a distinctively more suppressive TIME characterized by increased but immature TLSs, with higher naïve B-cell and follicular regulatory T-cell densities and downregulated TLS maturation-related cell ratios inside TLSs; increased naïve B-cell and regulatory T-cell densities; and a high proportion of exhausted T cells in the extra-TLS zone. The upregulated tumor PD-L1 expression and its close correlations with TLS formation and maturation were remarkable exclusively in GC-NED. TIME features, especially those regarding TLSs, were significantly correlated with tumor growth and invasion. The desynchrony between TLS formation and maturation and increased naïve or regulatory immune cell infiltration was observed in adenocarcinomas of the colorectum, pancreas, lung, and prostate. Conclusion: NED highlighted a distinct GC entity with more suppressive TIME features correlated with tumor behaviors, indicating a cohort that would benefit more from immunotherapies.

A cyclic peptide-based PROTAC induces intracellular degradation of palmitoyltransferase and potently decreases PD-L1 expression in human cervical cancer cells.

Our previous research has found that degradation of palmitoyltransferase in tumor cells using a linear peptide PROTAC leads to a significant decrease in PD-L1 expression in tumors. However, this degradation is not a sustained and efficient process. Therefore, we designed a cyclic peptide PROTAC to achieve this efficient anti-PD-L1 effect. We designed and synthesized an improvement in linear peptide PROTAC targeting palmitoyltransferase DHHC3, and used disulfide bonds to stabilize the continuous N- and C-termini of the peptides to maintain their structure. Cellular and molecular biology techniques were used to test the effect of this cyclic peptide on PD-L1. In human cervical cancer cells, our cyclic peptide PROTAC can significantly downregulate palmitoyl transferase DHHC3 and PD-L1 expressions. This targeted degradation effect is enhanced with increasing doses and treatment duration, with a DC50 value much lower than that of linear peptides. Additionally, flow cytometry analysis of fluorescence intensity shows an increase in the amount of cyclic peptide entering the cell membrane with prolonged treatment time and higher concentrations. The Cellular Thermal Shift Assay (CETSA) method used in this study indicates effective binding between our novel cyclic peptide and DHHC3 protein, leading to a change in the thermal stability of the latter. The degradation of PD-L1 can be effectively blocked by the proteasome inhibitor MG132. Results from clone formation experiments illustrate that our cyclic peptide can enhance the proliferative inhibition effect of cisplatin on the C33A cell line. Furthermore, in the T cell-C33A co-culture system, cyclic peptides target the degradation of PD-L1, thereby blocking the interaction between PD-L1 and PD-1, and promoting the secretion of IFN-γ and TNF-α in the co-culture system supernatant. Our results demonstrate that a disulfide-bridged cyclic peptide PROTAC targeting palmitoyltransferase can provide a stable and improved anti-PD-L1 activity in human tumor cells.

LBA57 Neoadjuvant nivolumab (N) + chemotherapy (C) in the phase III CheckMate 816 study: 3-y results by tumor PD-L1 expression

LBA57 Neoadjuvant nivolumab (N) + chemotherapy (C) in the phase III CheckMate 816 study: 3-y results by tumor PD-L1 expression

Métastases du système nerveux central: Central nervous system metastases

Lung cancer is the leading provider of brain metastases (BMs). The prevalence of BMs varies depending on pathology and can occur in up to 50% of non-small cell lung cancers (NSCLC) and 80% of small cell lung cancers (SCLC) during follow-up. BMs prevalence is also higher in case of oncogenic addictions such as EGFR mutations or ALK rearrangements. Furthermore, BMs result in significant morbidity and mortality. They are directly responsible for death in 50% of cases.BMs evolution and response to treatments is heterogeneous, and can be different from the primary tumor. This is due to molecular differences between BMs and primary tumors related to the blood-brain barrier (BBB) but also to a very different tumor microenvironment.Depending on pathology, tumor mutation profile and PDL1 expression, systemic treatments may be based on immunotherapy alone, a combination of chemotherapy and immunotherapy, or targeted therapies. More and more data are available on intracranial response of systemic treatments, including data for new treatments in development. In addition to systemic treatments, local treatments such as surgery, whole brain radio therapy (WBRT) or stereotactic radiotherapy (SBRT) should be considered. Local treatment choice mainly depends on the number and volume of brain lesions. Because of fewer side effects, SBRT is becoming an increasingly important part of treatment. On the contrary, prophylactic cranial irradiation is limited to SCLCs with good response to chemotherapy.1877-1203/© 2023 SPLF. Published by Elsevier Masson SAS. All rights reserved.