Programmed Death-ligand 1 Expression Research Articles

CD38 symmetric dimethyl site R58 promotes malignant tumor cell immune escape by regulating the cAMP-GSK3β-PD-L1 axis

In recent years, immunotherapy has emerged as an effective approach for treating tumors, with programmed cell death ligand 1 (PD-L1)/programmed cell death protein-1 (PD-1) immune checkpoint blockade (ICB) being a promising strategy. However, suboptimal therapeutic efficacy limits its clinical benefit. Understanding the regulation mechanism of PD-L1 expression is crucial for improving anti-PD-L1/PD-1 therapy and developing more effective tumor immunotherapy. Previous studies have revealed that resistance to PD-L1/PD-1 blockade therapy arises from the upregulation of CD38 on tumor cells induced by ATRA and IFN-β, which mediates the inhibition of CD8+ T cell function through adenosine receptor signaling, thereby promoting immune evasion.Yet, the precise role of CD38 in regulating PD-L1 on malignant tumor cells and its impact on CD8+ T cells through PD-L1 remain unclear. Here, we demonstrate that CD38 is highly expressed in malignant tumors (lung cancer, nasopharyngeal carcinoma, cervical cancer) and upregulates PD-L1 protein expression, impairing CD8+ T cell function. Mechanistically, CD38 phosphorylates GSK3β via the adenosine-activated cAMP-PKA signaling pathway, leading to GSK3β inactivation and enhanced PD-L1 stability and expression, facilitating tumor immune escape. Furthermore, we identify PRMT5 as a novel CD38-interacting molecule that symmetrically dimethylates CD38 arginine position 58, augmenting PD-L1 stability and expression through the ADO-cAMP-GSK3β signaling axis. This inhibits CD8+ T cell-mediated tumor cell killing, enabling tumor cells to evade immune surveillance. Our findings suggest that targeting the CD38 R58 site offers a new avenue for enhancing anti-PD-L1/PD-1 therapy efficacy in tumor treatment.

Beta cell extracellular vesicle PD-L1 as a novel regulator of CD8+ T cell activity and biomarker during the evolution of Type 1 Diabetes.

Surviving beta cells in type 1 diabetes respond to inflammation by upregulating programmed death-ligand 1 (PD-L1) to engage immune cell programmed death-1 (PD-1) and limit destruction by self-reactive immune cells. Extracellular vesicles (EVs) and their cargo can serve as biomarkers of beta cell health and contribute to islet intercellular communication. We hypothesized that the inflammatory milieu of type 1 diabetes increases PD-L1 in beta cell EV cargo and that EV PD-L1 may protect beta cells against immune-mediated cell death. Beta cell lines and human islets were treated with proinflammatory cytokines to model the proinflammatory type 1 diabetes microenvironment. EVs were isolated using ultracentrifugation or size exclusion chromatography and analysed via immunoblot, flow cytometry, and ELISA. EV PD-L1: PD-1 binding was assessed using a competitive binding assay and in vitro functional assays testing the ability of EV PD-L1 to inhibit NOD CD8 T cells. Plasma EV and soluble PD-L1 were assayed in plasma of individuals with islet autoantibody positivity (Ab+) or recent-onset type 1 diabetes and compared to non-diabetic controls. PD-L1 protein colocalized with tetraspanin-associated proteins intracellularly and was detected on the surface of beta cell EVs. 24-h IFN-α or IFN-γ treatment induced a two-fold increase in EV PD-L1 cargo without a corresponding increase in number of EVs. IFN exposure predominantly increased PD-L1 expression on the surface of beta cell EVs and beta cell EV PD-L1 showed a dose-dependent capacity to bind PD-1. Functional experiments demonstrated specific effects of beta cell EV PD-L1 to suppress proliferation and cytotoxicity of murine CD8 T cells. Plasma EV PD-L1 levels were increased in islet Ab+ individuals, particularly in those with single Ab+, Additionally, in from individuals with either Ab+ or type 1 diabetes, but not in controls, plasma EV PD-L1 positively correlated with circulating C-peptide, suggesting that higher EV-PD-L1 could be protective for residual beta cell function. IFN exposure increases PD-L1 on the beta cell EV surface. Beta cell EV PD-L1 binds PD1 and inhibits CD8 T cell proliferation and cytotoxicity. Circulating EV PD-L1 is higher in islet autoantibody positive patients compared to controls. Circulating EV PD-L1 levels correlate with residual C-peptide at different stages in type 1 diabetes progression. These findings suggest that EV PD-L1 could contribute to heterogeneity in type 1 diabetes progression and residual beta cell function and raise the possibility that EV PD-L1 could be exploited as a means to inhibit immune-mediated beta cell death.

High-resolution spiral microfluidic channel integrated electrochemical device for isolation and detection of extracellular vesicles without lipoprotein contamination

Recent studies have indicated significant correlation between the concentration of immune checkpoint markers borne by extracellular vesicles (EVs) and the efficacy of immunotherapy. This study introduces a high-resolution spiral microfluidic channel-integrated electrochemical device (HiMEc), which is designed to isolate and detect EVs carrying the immune checkpoint markers programmed death ligand 1 (PD-L1) and programmed death protein 1 (PD-1), devoid of plasma-abundant lipoprotein contamination. Antigen-antibody reactions were applied to immobilize the lipoproteins on bead surfaces within the plasma, establishing a size differential with EVs. A plasma sample was then introduced into the spiral microfluidic channel, which facilitated the acquisition of nanometer-sized EVs and the elimination of micrometer-sized lipoprotein-bead complexes, along with the isolation and quantification of EVs using HiMEc. PD-L1 and PD-1 expression on EVs was evaluated in 30 plasma samples (10 from healthy donors, 20 from lung cancer patients) using HiMEc and compared to the results obtained from standard tissue-based PD-L1 testing, noting that HiMEc could be utilized to select further potential candidates. The obtained results are expected to contribute positively to the clinical assessment of potential immunotherapy beneficiaries.

Sensitivity of CT-derived radiomic features to extraction libraries and gray-level discretization in the context of immune biomarker discovery.

Radiomics can predict patient outcomes by automatically extracting a large number of features from medical images. This study is aimed to investigate the sensitivity of radiomics features extracted from 2 different pipelines, namely, Pyradiomics and RaCat, as well as the impact of gray-level discretization on the discovery of immune checkpoint inhibitors (ICIs) biomarkers. A retrospective cohort of 164 non-small cell lung cancer patients administered with ICIs was used in this study. Radiomic features were extracted from the pre-treatment CT scans. Univariate models were used to assess the association of common radiomics features between 2 libraries with progression-free survival (PFS), programmed death ligand 1 (PD-L1), and tumour infiltrating lymphocytes (CD8 counts). In addition, we also examined the impact of gray-level discretization incorporated in Pyradiomics on the robustness of features across various clinical endpoints. We extracted 1224, 441 radiomic features using Pyradiomics and RaCat, respectively. Among these, 75 features were found to be common between the 2 libraries. Our analysis revealed that the directionality of association between radiomic features and clinical endpoints is highly dependent on the library. Notably, a larger number of Pyradiomics features were statistically associated with PFS, whereas RaCat features showed a stronger association with PD-L1 expression. Furthermore, intensity-based features were found to have a consistent association with clinical endpoints regardless of the gray-level discretization parameters in Pyradiomics-extracted features. This study highlights the heterogeneity of radiomics libraries and the gray-level discretization parameters that will impact the feature selection and predictive model development for biomarkers. Importantly, our work highlights the significance of standardizing radiomic features to facilitate translational studies that use imaging as an endpoint. Our study emphasizes the need to select stable CT-derived handcrafted features to build immunotherapy biomarkers, which is a necessary precursor for multi-institutional validation of imaging biomarkers.

The efficacy and safety of neoadjuvant immunochemotherapy in resectable stage I-III non-small cell lung cancer: a systematic review and network meta-analysis.

Neoadjuvant immunochemotherapy (NICT) is a new treatment method for resectable non-small-cell lung cancer (NSCLC). Network meta-analysis assessed efficacy, safety, and optimal treatment. We searched for randomized controlled trials (RCTs) comparing NICT with neoadjuvant chemotherapy (NCT) in PubMed, Embase, Web of Science, Cochrane Library, and international conferences. Outcomes were surgical resection rate, pathological complete response(pCR),event-free survival (EFS), and Grade 3-5 treatment-related adverse events (TRAEs). RCTs of 3,387 patients, six treatment combinations, and two modalities were included. Meta-analysis showed that NICT yielded higher pCR and EFS rates than NCT. The toripalimab-chemotherapy combination had the highest surgical resection rate (OR = 1.68, 95% CI: 1.05-2.73), pCR (OR = 38.84, 95% CI: 11.05-268.19) and EFS (HR = 0.40, 95% CI: 0.28-0.58).This regimen worked well for patients with low programmed death-ligand 1 (PD-L1) expression or squamous cell pathology. For high PD-L1 expression and patients with NSCLC, neoadjuvant nivolumab with chemotherapy had the most efficacy. The incidence of treatment-related adverse events increased with longer treatment cycles, with perioperative nivolumab combined with chemotherapy showing the worst safety profile (RR = 1.32, 95% CI: 1.00-1.76), while neoadjuvant nivolumab combined with chemotherapy alone had the best safety profile (RR = 0.91, 95% CI: 0.68-1.21). Indirect comparison showed no survival benefit for neoadjuvant-adjuvant immunotherapy (HR = 0.93, 95% CI: 0.65-1.35). In the indirect comparison between the two immune checkpoint inhibitors(ICIs), although there was no significant difference in EFS (HR = 0.81, 95% CI: 0.61-1.08), PD-1 inhibitors may still be the most effective treatment option. NICT effectively and safely treats resectable NSCLC. The optimal treatment combination is typically toripalimab and chemotherapy. Treatment based on PD-L1 expression and pathological type is recommended.

Zosuquidar Promotes Antitumor Immunity by Inducing Autophagic Degradation of PD-L1.

The intracellular distribution and transportation process are essential for maintaining PD-L1 (programmed death-ligand 1) expression, and intervening in this cellular process may provide promising therapeutic strategies. Here, through a cell-based high content screening, it is found that the ABCB1 (ATP binding cassette subfamily B member 1) modulator zosuquidar dramatically suppresses PD-L1 expression by triggering its autophagic degradation. Mechanistically, ABCB1 interacts with PD-L1 and impairs COP II-mediated PD-L1 transport from ER (endoplasmic reticulum) to Golgi apparatus. The treatment of zosuquidar enhances ABCB1-PD-L1 interaction and leads the ER retention of PD-L1, which is subsequently degraded in the SQSTM1-dependent selective autophagy pathway. In CT26 mouse model and a humanized xenograft mouse model, zosuquidar significantly suppresses tumor growth and accompanies by increased infiltration of cytotoxic T cells. In summary, this study indicates that ABCB1 serves as a negative regulator of PD-L1, and zosuquidar may act as a potential immunotherapy agent by triggering PD-L1 degradation in the early secretory pathway.

Durvalumab With or Without Tremelimumab in Combination With Chemotherapy in First-Line Metastatic NSCLC: Five-Year Overall Survival Outcomes From the Phase 3 POSEIDON Trial

IntroductionThe primary analysis (median follow-up 34.9 mo across all arms) of the phase 3 POSEIDON study revealed a statistically significant overall survival (OS) improvement with first-line tremelimumab plus durvalumab and chemotherapy (T+D+CT) versus CT in patients with EGFR and ALK wild-type metastatic NSCLC (mNSCLC). D+CT had a trend for OS improvement versus CT that did not reach statistical significance. This article reports prespecified OS analyses after long-term follow-up (median >5 y). MethodsA total of 1013 patients were randomized (1:1:1) to T+D+CT, D+CT, or CT, stratified by tumor cell programmed cell death ligand-1 (PD-L1) expression (≥50% versus <50%), disease stage (IVA versus IVB), and tumor histologic type (squamous versus nonsquamous). Serious adverse events were collected during follow-up. ResultsAfter a median follow-up of 63.4 months across all arms, T+D+CT had sustained OS benefit versus CT (hazard ratio [HR] = 0.76, 95% confidence interval [CI]: 0.64–0.89; 5-y OS: 15.7% versus 6.8%). OS improvement with D+CT versus CT (HR = 0.84, 95% CI: 0.72–1.00; 5-y OS: 13.0%) was consistent with the primary analysis. OS benefit with T+D+CT versus CT remained more pronounced in nonsquamous (HR = 0.69, 95% CI: 0.56–0.85) versus squamous (HR = 0.85, 95% CI: 0.65–1.10) mNSCLC. OS benefit with T+D+CT versus CT was still evident regardless of PD-L1 expression, including patients with PD-L1 tumor cell less than 1%, and remained evident in STK11-mutant (nonsquamous), KEAP1-mutant, and KRAS-mutant (nonsquamous) mNSCLC. No new safety signals were identified. ConclusionsAfter a median follow-up of more than 5 years, T+D+CT had durable long-term OS benefit versus CT, supporting its use as first-line treatment in mNSCLC, including in patient subgroups with harder-to-treat disease.

The expression of programmed cell death ligand 1 (PD-L1) involves in the clinicopathologic characteristics and prognostic implications of testicular germ cell tumor (TGCT): a systematic review and meta-analysis.

Testicular germ cell tumor (TGCT) is a type of tumor with relatively lower incidence but being more prevalent in young men. The expression of programmed cell death ligand 1 (PD-L1) serves as a potential biomarker for predicting the survival outcomes of other tumors. Some studies discovered higher prevalence of PD-L1 in TGCT patients who achieved favorable treatment outcomes, while other studies showed lower or absent expression of PD-L1 in TGCT with the better prognosis as well. Therefore, in order to address this controversy and clarify the association between the expression of PD-L1 and pathological features and prognosis of TGCT, this meta-analysis was conducted. A comprehensive literature search was performed using following search terms: "testis", "testicle", "testicular", "cancer", "carcinoma", "tumor", "neoplasm", "programmed cell death ligand 1", "programmed death ligand 1", "PD-L1", "PDL1", "B7 homolog 1", "B7-H1", "B7H1" and "CD274". Relevant studies were retrieved according to the inclusion criteria from reputable databases including PubMed, Embase, Web of Science, Cochrane Library and China National Knowledge Infrastructure (CNKI). These studies investigated the expression of PD-L1 in both tumor cells and tumor infiltrating immune cells (TIICs) in TGCT. The overall proportion of PD-L1 positivity was assessed using R programming. Pooled hazard ratio (HR) and odds ratio (OR) with corresponding 95% confidence interval (CI) were calculated using Revman software to evaluate the involvement of PD-L1 expression in TGCT. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality assessment of included studies. Sensitivity analysis and publication bias evaluation were subsequently performed. A total of eight eligible studies compromising 1,589 patients diagnosed with TGCT were finally included in this study. PD-L1 positivity was detected in 31% and 41% of TGCT patients' tumor cells and TIICs, respectively. The pooled data demonstrated a significant association between elevated PD-L1 expression levels in TIICs and a favorable prognosis characterized by the reduced disease progression and relapse events (HR =0.21, 95% CI: 0.13-0.33). Furthermore, PD-L1+ TIICs exhibited higher prevalence rates in seminoma (OR =2.11, 95% CI: 1.57-2.84) and embryonal carcinoma (OR =6.23, 95% CI: 2.42-16.02) patients. Notably, PD-L1 expression in TIICs displayed a tendency to increase in TGCT patients with lower stages or without lymph node metastasis. PD-L1 expression was observed in choriocarcinoma tumor cells, while yolk sac tumor and teratoma tumor cells exhibited lower or absent expression of PD-L1. Conversely, PD-L1 expression in TIICs was associated with seminoma and embryonal carcinoma, which was more commonly observed in TGCT patients with lower stages and better prognosis, thereby providing a theoretical foundation for the application of immunotherapy in relapsed/refractory TGCT patients.

Efficacy and safety of immune checkpoint inhibitors plus platinum-etoposide vs. platinum-etoposide in the first-line treatment of extensive-stage small cell lung cancer: a systematic review and a meta-analysis.

Currently, immune checkpoint inhibitors (ICIs) combined with platinum-etoposide (EP) are gradually becoming the first-line standard treatment for extensive-stage small cell lung cancer (ES-SCLC). This meta-analysis aims to compare the efficacy and safety of ICIs combined with EP vs. EP alone in the first-line treatment of ES-SCLC. We searched PubMed, Embase, and Cochrane Library databases for phase II/III randomized controlled trials (RCTs) that met inclusion criteria from January 2016 to November 2023. Outcome measures included progression-free survival (PFS), overall survival (OS), objective response rate (ORR), treatment-related adverse events (TRAEs), treatment-related serious adverse events (TRSAEs), and immune-related adverse events (IRAEs). The effect analysis statistics of the outcome indicators were expressed with hazard ratio (HR) and odds ratio (OR) and their 95% confidence interval (CI). This study included nine RCTs with a total of 4,711 patients. Compared to EP, ICIs plus EP improved patients' PFS (HR =0.71; 95% CI: 0.64-0.79; P<0.001), OS (HR =0.79; 95% CI: 0.74-0.84; P<0.001), and ORR (OR =1.27; 95% CI: 1.12-1.44; P=0.001), but increased the incidence of adverse events (AEs): TRAEs (OR =1.45; 95% CI: 1.20-1.76; P<0.001), IRAEs (OR =3.97; 95% CI: 2.49-6.32; P<0.001), and grade 3-4 IRAEs (OR =6.17; 95% CI: 2.36-16.15; P<0.001). However, there was no significant difference in the incidence of grade 3-4 TRAEs (OR =1.05; P=0.54), TRSAEs (OR =1.40; P=0.13), and grade 3-4 TRSAEs (OR =1.17; P=0.72). Subgroup analysis found that patients with brain metastasis did not benefit from ICIs combined with EP therapy, and patients with programmed cell death ligand 1 (PD-L1) expression ≥1% had poorer survival benefits compared to patients with PD-L1 expression <1%. In the first-line treatment of ES-SCLC, compared to EP chemotherapy, ICIs with EP can benefit patients in terms of PFS, OS, and ORR, but it will increase the occurrence of AEs.

Study on the mechanism of liver cancer immune escape mediated by MINDY1 through regulation of PD-L1 ubiquitination level.

The novel deubiquitinase enzyme, motif interacting with ubiquitin-containing novel DUB family-1 (MINDY1), is highly expressed in liver cancer tissues and plays a crucial role in maintaining the stemness of liver cancer cells. Programmed death ligand-1 (PD-L1) is an immunosuppressive molecule overexpressed by tumour cells. The potential role of MINDY1 in inhibiting the stemness of liver cancer cells by deubiquitinating PD-L1 has not yet been reported. To investigate the mechanism by which MINDY1 mediates immune escape in liver cancer through the regulation of PD-L1 ubiquitination, we examined the expression levels of MINDY1 and PD-L1 in liver cancer and adjacent tissues from 50 hepatocellular carcinoma (HCC) patients using protein imprinting and immunohistochemistry. We analyzed the relationship between the expression levels of MINDY1 and PD-L1 in liver cancer tissues and their correlation with the 5-year tumor-free survival rates of patients. Subsequently, MINDY1 expression was knocked down in Huh7 cells using small interfering RNA (siRNA) interference or upregulated through transfection with a MINDY1 overexpression plasmid. The effects of MINDY1 knockdown or overexpression on the proliferation, apoptosis, migration, and invasion of HCC cells, as well as the regulation of PD-L1 binding and ubiquitination, were assessed. The 5-year tumor-free survival rates were significantly lower in both the high MINDY1 expression group and the high PD-L1 expression group (χ2 = 4.919 and 13.158, respectively).A significant difference in survival was observed between the high and low MINDY1 expression groups (χ2= 27.415). MINDY1 was found to directly interact with PD-L1, with MINDY1 gene knockdown promoting PD-L1 ubiquitination and MINDY1 overexpression inhibiting PD-L1 ubiquitination. All comparisons yielded statistically significant results (P < 0.05). In conclusion, MINDY1 inhibits the malignant progression of liver cancer by inhibiting PD-L1 ubiquitination and mediating immune escape.

Preliminary Research of Radiolabeled Atezolizumab for the Noninvasive Evaluation of TNBC PD-L1 Expression InVivo.

Programmed death-ligand 1 (PD-L1) expression is related to the efficacy and prognosis in triple-negative breast cancer. This study employed an indirect labeling method to synthesize [125I]PI-Atezolizumab. The invitro stability of [125I]PI-Atezolizumab was assessed through incubation in phosphate buffered saline and fetal bovine serum, revealing sustained stability. Specific binding of [125I]PI-Atezolizumab to MDA-MB-231 cells expressing humanized PD-L1 was assessed through invitro incubation, yielding a Kd value comparable to that of Atezolizumab. This suggests that the labeling process did not compromise the affinity of the Atezolizumab to PD-L1. Subsequently, pharmacokinetic studies were conducted in normal mice and biodistribution experiments in tumor-bearing mice. A comparison of the biodistribution results between [125I]PI-Atezolizumab and 125I-labeled Atezolizumab indicated better invivo stability for the former. Single photon emission computed tomography (SPECT)/CT imaging further confirmed the targeted specificity of [125I]PI-Atezolizumab for PD-L1 in MDA-MB-231 xenografts, which were validated by immunohistochemistry staining. This research underscores the utility of [125I]PI-Atezolizumab, prepared via indirect labeling, for monitoring PD-L1 in triple-negative breast cancer models.

Medullary carcinomas of the nonampullary small intestine: association with coeliac disease, mismatch repair deficiency, PD-L1 expression, and favourable prognosis.

Gastrointestinal medullary carcinoma is a rare histologic subtype of adenocarcinoma. As nonampullary small bowel medullary carcinomas (SB-MCs) are poorly characterized, we aimed to analyse their clinicopathologic and immunohistochemical features and to compare them with nonmedullary small bowel adenocarcinomas (NM-SBAs). Surgically resected SBAs collected through the Small Bowel Cancer Italian Consortium were classified as SB-MCs (carcinomas with ≥50% of tumour fulfilling the typical histologic criteria of MC) or NM-SBAs. Immunohistochemistry for cytokeratin (CK)7, CK20, CDX2, programmed death-ligand 1 (PD-L1) and mismatch repair proteins was performed in both SB-MCs and NM-SBAs. SB-MCs were also tested for CK8/18, synaptophysin, SMARCB1, SMARCA2, SMARCA4, and ARID1A and for Epstein-Barr virus (EBV)-encoded RNAs by in-situ hybridization. MLH1 promoter methylation status was evaluated in MLH1-deficient cases. Eleven SB-MCs and 149 NM-SBAs were identified. One (9%) SB-MC was EBV-positive, while 10 (91%) harboured mismatch repair deficiency (dMMR). MLH1 promoter hypermethylation was found in all eight dMMR SB-MCs tested. Switch/sucrose nonfermentable deficiency was seen in two (18%) SB-MCs, both with isolated loss of ARID1A. Compared with NM-SBAs, SB-MCs exhibited an association with coeliac disease (P < 0.001), higher rates of dMMR (P < 0.001), and PD-L1 positivity by both tumour proportion score and combined positive score (P < 0.001 for both), and a lower rate of CK20 expression (P = 0.024). Survival analysis revealed a better prognosis of SB-MC patients compared to NM-SBA cases (P = 0.02). SB-MCs represent a distinct histologic subtype, with peculiar features compared to NM-SBAs, including association with coeliac disease, dMMR, PD-L1 expression, and better prognosis.

PD-L1 expression as a predictive biomarker in patients with recurrent or metastatic salivary gland carcinoma treated with pembrolizumab

Although immune checkpoint inhibitors (ICIs) are effective in some patients with salivary gland carcinoma (SGC), biomarkers which predict the efficacy and prognosis of SGC patients treated with pembrolizumab have not been identified. We conducted a multi-institutional retrospective cohort study to evaluate the efficacy and safety of pembrolizumab monotherapy in patients with recurrent and/or metastatic SGC and to determine optimal cut-off values of the combined positive score (CPS) and tumor proportion score (TPS) as numerical expression levels of programmed death-ligand 1 (PD-L1), which predict the efficacy of pembrolizumab. Furthermore, we investigated the association of patient characteristics and hematological markers with clinical outcomes, including overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). From 2016 to 2021, 27 patients were included in the analysis. ORR of SGC was 25.9%. Optimal cut-off values of CPS and TPS were 15 and 25%, respectively. ORRs of CPS-high and TPS-high were 55.6 and 75.0%, respectively, and significantly higher than those of CPS-low and TPS-low. Furthermore, patients with a low platelet-lymphocyte ratio (PLR) had a significantly longer PFS. No grade 4 or greater adverse events were observed. This study demonstrated the efficacy and safety of pembrolizumab monotherapy and identified optimal cut-off values of CPS and TPS.

ROS-sensitive PD-L1 siRNA cationic selenide nanogels for self-inhibition of autophagy and prevention of immune escape

In the field of cancer therapy, inhibiting autophagy has emerged as a promising strategy. However, pharmacological disruption of autophagy can lead to the upregulation of programmed death-ligand 1 (PD-L1), enabling tumor immune evasion. To address this issue, we developed innovative ROS-responsive cationic poly(ethylene imine) (PEI) nanogels using selenol chemistry-mediated multicomponent reaction (MCR) technology. This procedure involved simple mixing of low-molecular-weight PEI (LMW PEI), γ-selenobutylacetone (γ-SBL), and poly(ethylene glycol) methacrylate (PEGMA). Through high-throughput screening, we constructed a library of AxSeyOz nanogels and identified the optimized A1.8Se3O0.5/siPD-L1 nanogels, which exhibited a size of approximately 200 nm, excellent colloidal stability, and the most effective PD-L1 silencing efficacy. These nanogels demonstrated enhanced uptake by tumor cells, excellent oxidative degradation ability, and inhibited autophagy by alkalinizing lysosomes. The A1.8Se3O0.5/siPD-L1 nanogels significantly downregulated PD-L1 expression and increased the expression of major histocompatibility complex class I (MHC-I), resulting in robust proliferation of specific CD8+ T cells and a decrease in MC38 tumor growth. As a result, the A1.8Se3O0.5/siPD-L1 nanogels inhibited tumor growth through self-inhibition of autophagy, upregulation of MHC-I, and downregulation of PD-L1. Designed with dynamic diselenide bonds, the A1.8Se3O0.5/siPD-L1 nanogels showed synergistic antitumor efficacy through self-inhibition of autophagy and prevention of immune escape.

No Correlation between PD-L1 and NIS Expression in Lymph Node Metastatic Papillary Thyroid Carcinoma.

Approximately 90% of thyroid cancers are differentiated thyroid cancers (DTCs), originating from follicular epithelial cells. Out of these, 90% are papillary thyroid cancer (PTC), and 10% are follicular thyroid cancer (FTC). The standard care procedure for PTC includes surgery, followed by radioiodine (RAI) ablation and thyroid-stimulating hormone (TSH) suppressive therapy. Globally, treating radioiodine-refractory DTC poses a challenge. During malignant transformation, thyroid epithelial cells often lose their ability to absorb radioiodine due to impaired membrane targeting or lack of NIS (sodium/iodide symporter) expression. Recent reports show an increase in PD-L1 (programmed death ligand 1) expression in thyroid cancer cells during dedifferentiation. However, no research exists wherein NIS and PD-L1 expression are analyzed together in thyroid cancer. Therefore, we aimed to investigate and correlate PD-L1 and NIS expression within primary tumor samples of lymph node metastatic PTC. We analyzed the expression of hNIS (human sodium/iodide symporter) and PD-L1 in primary tumor samples from metastatic PTC patients using immunohistochemistry. Immunohistochemistry analysis of PD-L1 and NIS was conducted in 89 and 86 PTC cases, respectively. Any subcellular NIS localization was counted as a positive result. PD-L1 expression was absent in 25 tumors, while 58 tumors displayed PD-L1 expression in 1-50% of their cells; in 6 tumors, over 50% of the cells tested positive for PD-L1. NIS immunohistochemistry was performed for 86 primary papillary carcinomas, with 51 out of 86 tumors showcasing NIS expression. Only in seven cases was NIS localized in the plasma membrane; in most tumors, NIS was primarily found in the intracytoplasmic membrane compartments. In the case of PD-L1 staining, cells showing linear membrane positivity of any intensity were counted as positive. The evaluation of NIS immunostaining was simpler: cells showing staining of any intensity of cytoplasmic or membranous fashion were counted as positive. The number of NIS positive cells can be further divided into cytoplasmic and membrane positive compartments. There was no observed correlation between PD-L1 and NIS expression. We can speculate that the manipulation of the PD-1/PD-L1 axis using anti-PD-L1 or anti-PD-1 antibodies could reinstate the functional expression of NIS. However, based on our study, the only conclusion that can be drawn is that there is no correlation between the percentage of NIS- or PD-L1-expressing tumor cells in the primary tumor of lymph node metastatic PTC.

The prognostic value of programmed death-ligand 1 (PD-L1) expression in resected colorectal cancer without neoadjuvant therapy - differences between antibody clones and cell types

BackgroundProgrammed death-ligand 1 (PD-L1) expression on tumor cells is associated with poor prognosis in several malignancies, while partly contradictory and inconclusive results have been presented for colorectal cancer (CRC). This study aimed to evaluate PD-L1 as a prognostic biomarker in CRC by comparing three different antibody clones.MethodsPatients surgically treated for CRC between January 1st, 2007, and December 31st, 2015, in Kalmar County, Sweden, were retrospectively included. Tissue microarrays from 862 primary tumors without neoadjuvant treatment were assessed for immunohistochemical expression of PD-L1 in tumor cells (TC) and immune cells (IC) using clones 73-10, SP263, and 22C3. Cox regression proportional hazard models were used to estimate hazard ratios for overall survival (OS) and disease-free interval (DFI) in univariable and multivariable analyses, with 1% and 5% set as cut-offs for positive expression in TC and IC respectively.ResultsPD-L1 expression in TC was found in 89 (10%) cases for clone 73-10, 76 (9%) for clone SP263, and 38 (4%) for clone 22C3, while the numbers for IC were 317 (37%) cases for clone 73-10, 264 (31%) for clone SP263, and 89 (10%) for clone 22C3. PD-L1 expression in IC was associated with prolonged OS and DFI in univariable analysis for all three clones. The link to prolonged DFI remained in multivariable analysis for 73-10 and SP263, but only for 73-10 regarding OS. PD-L1 expression in TC was not prognostic of OS in any analysis, while it was associated with prolonged DFI for SP263, and a trend was seen for 73-10. The link to prolonged DFI remained for SP263 and was strengthened for 73-10 in multivariable analysis.ConclusionsThe prognostic value of PD-L1 expression in both IC and TC differs between antibody clones, with 73-10 and SP263 being more reliable for prognostic information than 22C3 in resected CRC.

Multispectral fluorescence imaging of EGFR and PD-L1 for precision detection of oral squamous cell carcinoma: a preclinical and clinical study

BackgroundEarly detection and treatment are effective methods for the management of oral squamous cell carcinoma (OSCC), which can be facilitated by the detection of tumor-specific OSCC biomarkers. The epidermal growth factor receptor (EGFR) and programmed death-ligand 1 (PD-L1) are important therapeutic targets for OSCC. Multispectral fluorescence molecular imaging (FMI) can facilitate the detection of tumor multitarget expression with high sensitivity and safety. Hence, we developed Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes, in combination with multispectral FMI, to sensitively and noninvasively identify EGFR and PD-L1 expression for the detection and comprehensive treatment of OSCC.MethodsThe expression of EGFR and PD-L1 was analyzed using bioinformatics data sources and specimens. Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes were developed and tested on preclinical OSCC cell line and orthotopic OSCC mouse model, fresh OSCC patients’ biopsied samples, and further clinical mouthwash trials were conducted in OSCC patients.ResultsEGFR and PD-L1 were specifically expressed in human OSCC cell lines and tumor xenografts. Nimotuzumab-ICG and Atezolizumab-Cy5.5 imaging probes can specifically target to the tumor sites in an in situ human OSCC mouse model with good safety. The detection sensitivity and specificity of Nimotuzumab-ICG in patients were 96.4% and 100%, and 95.2% and 88.9% for Atezolizumab-Cy5.5.ConclusionsEGFR and PD-L1 are highly expressed in OSCC, the combination of which is important for a precise prognosis of OSCC. EGFR and PD-L1 expression can be sensitively detected using the newly synthesized multispectral fluorescence imaging probes Nimotuzumab-ICG and Atezolizumab-Cy5.5, which can facilitate the sensitive and specific detection of OSCC and improve treatment outcomes.Trial registrationChinese Clinical Trial Registry, ChiCTR2100045738. Registered 23 April 2021, https://www.chictr.org.cn/bin/project/edit?pid=125220

Five-year outcomes with first-line nivolumab plus ipilimumab with 2 cycles of chemotherapy versus 4 cycles of chemotherapy alone in patients with metastatic non-small cell lung cancer in the randomized CheckMate 9LA trial

BackgroundWe report 5-year efficacy and safety outcomes from CheckMate 9LA in patients with metastatic non-small cell lung cancer (mNSCLC) and exploratory analyses in key patient subgroups. MethodsAdults with stage IV/recurrent NSCLC and no sensitizing EGFR/ALK alterations were randomized to receive nivolumab plus ipilimumab with chemotherapy (n = 361) or chemotherapy (n = 358). Outcomes were assessed in all randomized patients and subgroups. ResultsWith 57.3 months’ minimum follow-up, patients continued to derive overall survival (OS) benefit with nivolumab plus ipilimumab with chemotherapy over chemotherapy (HR, 0.73; 95% CI, 0.62–0.85; 5-year OS rates, 18% vs. 11%), regardless of tumor programmed death ligand 1 (PD-L1) expression (PD-L1 < 1%, 22% vs. 8%; PD-L1 ≥ 1%, 18% vs. 11%), histology (squamous, 18% vs. 7%; non-squamous, 19% vs. 12%), or presence of baseline brain metastases (20% vs. 6%). Five-year duration of response (DOR) rates were 19% versus 8% with nivolumab plus ipilimumab with chemotherapy versus chemotherapy, with consistent benefit across subgroups. Patients who discontinued nivolumab plus ipilimumab with chemotherapy due to treatment-related adverse events had a 5-year OS rate of 37%. Five-year progression-free survival and DOR rates in 5-year survivors were 55% versus 38% and 59% versus 46%, respectively. No new safety signals were observed in 5-year survivors, regardless of the number of ipilimumab doses received. ConclusionThis 5-year update supports the long-term, durable OS benefit and improved 5-year survivorship with nivolumab plus ipilimumab with chemotherapy over chemotherapy in patients with mNSCLC, regardless of tumor PD-L1 expression or histology. ClinicalTrials.gov registrationNCT03215706

Exogenous PD-L1 binds to PD-1 to alleviate and prevent autism-like behaviors in maternal immune activation-induced male offspring mice

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder caused by the interaction of multiple pathogenic factors. Epidemiological studies and animal experiments indicate that maternal immune activation (MIA) is closely related to the development of ASD in offspring. A large number of pro-inflammatory cytokines are transferred from the placenta to the fetal brain during MIA, which impedes fetal neurodevelopment and is accompanied by activation of immune cells and microglia. Programmed cell death protein 1 (PD-1) can be highly expressed on the surface of various activated immune cells, when combined with programmed cell death-ligand 1 (PD-L1), it can activate the PD-1/PD-L1 pathway and exert powerful immunosuppressive effects, suggesting that this immune checkpoint may have the potential to treat MIA-induced ASD. This study combined bioinformatics analysis and experimental validation to explore the efficacy of Fc-fused PD-L1 (PD-L1-Fc) in treating MIA-induced ASD. Bioinformatics analysis results showed that in human placental inflammation, IL-6 was upregulated, T cells proliferated significantly, and the PD-1/PD-L1 pathway was significantly enriched. The experimental results showed that intraperitoneal injection of poly(I:C) induced MIA in pregnant mice resulted in significant expression of IL-6 in their serum, placenta, and fetal brain. At the same time, the expression of PD-1 and PD-L1 in the placenta and fetal brain increased, CD4+ T cells in the spleen were significantly activated, and PD-1 expression increased. Their offspring mice exhibited typical ASD-like behaviors. In vitro experiments on primary microglia of offspring mice have confirmed that the expression of IL-6, PD-1, and PD-L1 is significantly increased, and PD-L1-Fc effectively reduced their expression levels. In the prefrontal cortex of MIA offspring mice, there was an increase in the expression of IL-6, PD-1, and PD-L1; activation of microglial cells, and colocalization with PD-1. Then we administered brain stereotaxic injections of PD-L1-Fc to MIA offspring mice and intraperitoneal injections to MIA pregnant mice. The results indicated that PD-L1-Fc effectively suppressed neuroinflammation in the frontal cortex of offspring mice and partially ameliorated ASD-like behaviors; MIA in pregnant mice was significantly alleviated, and the offspring mice they produced did not exhibit neuroinflammation or ASD-like behaviors. In summary, we have demonstrated the therapeutic ability of PD-L1-Fc for MIA-induced ASD, aiming to provide new strategies and insights for the treatment of ASD.

PD-L1 expression and tumor-infiltrating lymphocytes: Correlations and prognostic values in Chinese triple-negative breast cancer patients with different molecular subtyping

ObjectiveTo investigate the correlation between programmed death ligand-1 (PD-L1) expression and tumor-infiltrating lymphocytes (TILs) and evaluate the prognostic value of PD-L1 and TILs in Chinese triple-negative breast cancer (TNBC) patients with different molecular subtype MethodsThis retrospective study was conducted at 2020. Specifically, the pre-chemotherapy clinical data and non-stained tissue blocks of 465 TNBC patients visited the Fudan University Shanghai Cancer Center (FUSCC) between 2008 and 2014 were collected, with their blocks sliced and stained using PD-L1(SP142), and the outcome of subsequent chemotherapy obtained in 2020. The relapse-free survival (RFS) of the study population was calculated. The baseline PD-L1 expression status correlations with TILs and molecular subtypes were assessed using Spearman’s rank correlation analysis and the Kruskal-Wallis test. Kaplan-Meier survival analyses were undertaken to evaluate the prognosis value of TILs and PD-L1 expression. ResultsPD-L1 expression status on IC was moderately and positively correlated with stromal tumor-infiltrating lymphocytes (sTILs) (rs = 0.502, P <0.001) and iTILs (rs = 0.410, P < 0.001), respectively. PD-L1 expression status and TILs showed significant differences among molecular subtypes (P < 0.001), with the highest proportion of PD-L1+ and high TILs patients observed in the immunomodulatory (IM) subtype. TILs were significantly associated with RFS. Moreover, sTILs could act as an independent predictor of RFS (RR 0.953, 95 % CI 0.920 ∼ 0.987, P = 0.007), while PD-L1 expression status did not show the same prognostic significance. ConclusionsThe incorporation of pre-treatment TILs and PD-L1 expression status as valuable tools for optimizing patient selection for immunotherapy and managing the risks associated with chemotherapy in Chinese TNBC patients. Data availabilityThe data sets generated and analyzed during the current study are available from the corresponding author.