Search Results (367)

Background/Objectives: Monoclonal antibodies targeting the PD-1/PD-L1 immune checkpoint have achieved clinical success but face drawbacks such as poor oral bioavailability, limited tumor penetration, and immune-related adverse events. Small-molecule inhibitors present a promising alternative that may overcome these challenges. Methods: Here, an integrated computational framework combining ligand-based pharmacophore modeling and structure-based molecular docking was utilized to screen a comprehensive library consisting of traditional Chinese medicine-derived compounds and clinically approved drugs. The binding affinity between identified candidate compounds and PD-L1 was quantitatively assessed using bio-layer interferometry (BLI). In vitro cytotoxicity assays were conducted on A549 human lung carcinoma and LLC mouse lung carcinoma cell lines. In vivo antitumor efficacy was evaluated in LLC tumor-bearing mice through measurement of tumor growth inhibition, serum cytokine levels (IFN-γ and IL-4) by ELISA, and expression levels of IFN-γ and granzyme B (GZMB) within tumor tissues via immunohistochemistry. Results: In vitro, anidulafungin exhibited anti-tumor effects against both human lung cancer A549 cells and mouse Lewis lung carcinoma (LLC) tumor cells, with IC₅₀ values of 170.6 µg/mL and 160.9 µg/mL, respectively. The BLI analysis revealed a dissociation constant (K_D) of 76.9 μM, indicating a high affinity of anidulafungin for PD-L1. In vivo, anidulafungin significantly increased serum levels of IFN-γ and IL-4 in tumor-bearing mice and elevated expression of IFN-γ and granzyme B (GZMB) in tumor tissues, confirming its immune-mediated anti-tumor effects. Conclusions: Anidulafungin represents a promising small-molecule PD-L1 inhibitor, demonstrating significant anti-tumor potential via immune activation and highlighting the feasibility of repurposing approved drugs for cancer immunotherapy. Full article

Overexpression of growth factor receptors and immunosuppressive molecules is a hallmark of many tumour cells, distinguishing them from normal tissue. This co-expression enables tumours both to exploit proliferative signalling and to evade immune surveillance. Here, we propose a strategy that employs a combination of monoclonal antibodies (mAbs) targeting two distinct antigens (Ags) at sub-cytotoxic doses. This approach aims to achieve a threshold cytotoxic density of immune complexes selectively on malignant cells expressing both target Ags, while sparing normal cells that express only one. Typically, the first target Ag may be a growth factor receptor, such as epidermal growth factor receptor (EGFR and HER1), epidermal growth factor receptor 2 (HER2), or vascular endothelial growth factor receptor 2 (VEGFR2), and the second, an immunoinhibitory molecule, such as programmed death-ligand 1 (PD-L1). Selective mAb-mediated tumour destruction is expected to enhance neoantigen (NeoAg) presentation to the immune system, while the blockade of PD-1/PD-L1 interactions should further stimulate anti-tumour immune responses. Notably, this strategy can be implemented using clinically approved therapeutic mAbs, potentially enabling rapid translation into clinical practice without extensive regulatory hurdles. Full article

Background/Objectives: The TOPAZ-1 phase III trial reported a survival benefit of using durvalumab, an anti-programmed death ligand 1 (anti-PD-L1) antibody, in combination with gemcitabine and cisplatin (GCD) treatment in patients with advanced biliary tract cancer. This retrospective study investigated the efficacy and safety of GCD treatment for advanced biliary tract cancer in real-world conditions. Methods: The study subjects were 52 patients with biliary tract cancer who received GCD therapy between January 2023 and May 2024. The observation parameters included the modified Glasgow Prognostic Score (mGPS), neutrophil–lymphocyte ratio (NLR), platelet–lymphocyte ratio (PLR), tumor markers (CEA, CA19-9), overall response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and adverse events. Results: The cohort included 36 men and 16 women, with a median age of 73.0 years. There were 36 cases of cholangiocarcinoma (distal: 10, perihilar: 19, intrahepatic: 7), 13 cases of gallbladder cancer, and 3 cases of ampullary carcinoma. The stages were locally advanced in 30 cases and metastatic in 22 cases. Biliary drainage was performed in 30 cases. There were 38 cases receiving first-line therapy and 14 cases receiving second-line or later treatments. The median values at the start of GCD therapy were ALB 3.7 g/dL, CRP 0.39 mg/dL, NLR 2.4, PLR 162.5, CEA 4.8 ng/mL, and CA19-9 255.9 U/mL. The mGPS distribution was 0:23 cases, 1:18 cases, and 2:11 cases. The treatment outcomes were ORR 25.0% (CR 2 cases, PR 11 cases), DCR 78.8% (SD 28 cases, PD 10 cases, NE 1 case), median PFS 8.6 months, and median OS 13.9 months. The PLR was suggested to be useful for predicting PFS. A decrease in CEA at six weeks after the start of treatment was a significant predictor of PFS and OS. Gallbladder cancer had a significantly poorer prognosis compared to other cancers. The immune-related adverse events included hypothyroidism in two cases, cholangitis in one case, and colitis in one case. Conclusions: The ORR, DCR, and PFS were comparable to those in the TOPAZ-1 trial. Although limited by its retrospective design and small sample size, this study suggests that GCD therapy is an effective treatment regimen for unresectable biliary tract cancer in real-world clinical practice. Full article

Although PD-1/PD-L1 inhibitors have transformed cancer immunotherapy, a substantial proportion of patients derive no clinical benefit due to resistance driven by the tumour microenvironment (TME). Transforming growth factor-β (TGF-β) is a key immunosuppressive cytokine implicated in this resistance. Several bifunctional antibodies that co-target PD-1 and TGF-β signalling have entered clinical trials and shown encouraging efficacy, but the mechanistic basis of their synergy is not fully understood. Here, we engineered 015s, a bifunctional fusion antibody that simultaneously targets murine PD-1 and TGF-β and evaluated its antitumour efficacy and mechanistic impact in pre-clinical models. Antibody 015s exhibited high affinity, dual target binding, and the effective inhibition of PD-1 and TGF-β signalling. In vivo, 015s significantly suppressed tumour growth compared with anti-mPD-1 or TGF-β receptor II (TGF-βRII) monotherapy. When combined with the CD24-targeted ADC, 015s produced even greater antitumour activity and achieved complete tumour regression. Mechanistic studies demonstrated that 015s significantly reduced tumour cell migration and invasion, reversed epithelial–mesenchymal transition (EMT), decreased microvascular density, and attenuated collagen deposition within the TME. Antibody 015s also decreased bioactive TGF-β1 and increased intratumoural IFN-γ, creating a more immunostimulatory milieu. These findings support further development of PD-1/TGF-β bifunctional antibodies for cancers with high TGF-β activity or limited response to immune checkpoint blockade. Full article

Background/Objectives: Bladder cancer is a malignant disease that causes more than 199,922 deaths a year globally, in which ~75% of all newly diagnosed cases are non-muscle-invasive bladder cancer (NMIBC). Despite a number of treatments available, most NMIBC patients with high-grade tumors eventually recur. To add a novel therapy to complement the deficits of the current treatments, this study assesses the antitumor activity and mechanisms of action of intravesical xenogeneic urothelial cell (XUC) treatment as monotherapy and in combination with either chemotherapy or immune checkpoint inhibition (ICI). Methods: The orthotopic NMIBC graft tumor-bearing mice were randomly assigned into different treatment groups, receiving either intravesical XUCs, gemcitabine, anti-programmed death-ligand 1 (PD-L1) antibodies alone or in combination with gemcitabine or anti-PD-1 antibodies. The tumor responses, survival, and immune reactions were analyzed. Results: Intravesical XUC treatment exhibited significantly more antitumor activity to delay tumor progression than the control group and a similar effect to chemotherapy and ICI. In addition, there were significantly higher effects in the combined groups than single treatments. Immune tumor microenvironment and immune cell proliferation, cytotoxicity, and cytokine secretion were also activated by XUC treatment. Moreover, the combined groups have the highest effects. Conclusions: In vivo and ex vivo studies showed increased antitumor efficacy and immune responses by intravesical XUC treatment in single and combined treatments, suggesting a potential utility of this xenogeneic cell immunotherapeutic agent. Intravesical XUC treatment has the potential to address the substantial unmet need in NMIBC therapy as a bladder-sparing treatment option for NMIBC. Full article

Background/Objectives: Head and neck squamous cell carcinoma (HNSCC) is the seventh most prevalent cancer worldwide. Despite intensive treatments, the prognosis is unfavorable. Recently, immunotherapy has emerged as a novel therapeutic strategy, and several immune-checkpoint blockade blockers provide clinical benefits to patients. However, the response rates of these antibodies are limited, and there is a pressing need to increase the efficacy of immunotherapy for HNSCC patients. Epigenetic treatment is emerging as a promising combination approach able to change immune-related gene signatures in tumors and potentially increase the efficacy of immunotherapy. In this study, we sought to elucidate further immune-related gene signatures altered through epigenetic treatment and explored whether epigenetic drugs can increase the efficacy of anti PD-L1 treatment in HNSCC. Methods: At first, we treated six HNSCC cell lines with 5-azacytidine and romidepsin and analyzed gene expression patterns by microarray and TaqMan arrays analysis. We then explored the therapeutic efficacy of epigenetic treatment with an anti PD-L1 antibody in a syngeneic mouse model. Results: Our microarray analysis revealed the differential expression of immune-related genes in cell lines treated with epigenetic drugs, as compared to untreated controls. Most importantly, these array analyses showed a significant change in the transcription of some immune related-and biologically relevant genes, such as HLA-DRA, HMOX1, IFI6, IL12A, IRF7, NFKB2, RPL3L, STAT1, STAT3, CSF1, CSF2, FAS, OASL, and PD-L1, after epigenetic treatment. Furthermore, the combination of epigenetic treatment with an anti PD-L1 antibody significantly suppressed tumor growth in a syngeneic mouse model. In vivo tumors treated with epigenetic drugs expressed higher STAT1, STAT3, and PD-L1 compared to untreated tumors. Increased PD-L1 expression is postulated to increase the efficacy of anti PD-L1 treatment. Conclusions: Our results highlight the importance of a combinational strategy employing both epigenetic and immunotherapy in HNSCC. Full article

Tumor immunotherapy has revolutionized cancer treatment by harnessing the immune system to recognize and eliminate malignant cells, with immune checkpoint inhibitors targeting programmed death receptor 1 (PD-1), programmed death-ligand 1 (PD-L1), and cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) demonstrating remarkable clinical success. However, challenges such as treatment resistance, immune-related adverse effects, and high costs highlight the need for novel therapeutic approaches. Aptamers, short, single-stranded oligonucleotides with high specificity and affinity for target molecules, have emerged as promising alternatives to conventional antibody-based therapies. This review provides a comprehensive analysis of aptamer-based strategies targeting immune checkpoints, with a particular focus on PD-1/PD-L1 and CTLA-4. We summarize recent advances in aptamer design, including bispecific and multifunctional aptamers, and explore their potential in overcoming immune resistance and improving therapeutic efficacy. Additionally, we discuss strategies to enhance aptamer stability, bioavailability, and tumor penetration through chemical modifications and nanoparticle conjugation. Preclinical and early clinical studies have demonstrated that aptamers can effectively block immune checkpoint pathways, restore T-cell activity, and synergize with other immunotherapeutic agents to achieve superior anti-tumor responses. By systematically reviewing the current research landscape and identifying key challenges, this review aims to provide valuable insights into the future directions of aptamer-based cancer immunotherapy, paving the way for more effective and personalized treatment strategies. Full article

Background/Objectives: Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy; however, reliable biomarkers of therapeutic efficacy remain limited. We investigated the clinical utility of plasma WFDC2 levels in patients receiving anti-PD-1 antibody treatment. Methods: Twenty-one patients with non-small cell lung, gastric, or bladder cancer received nivolumab or pembrolizumab. Plasma WFDC2 concentrations were measured by ELISA before ICI treatment (pre-ICI) and after two and four treatment cycles. Associations between WFDC2 expression changes and overall survival (OS), progression-free survival (PFS), and tumor progression were assessed. ROC curve analyses compared the predictive performance of WFDC2, soluble PD-L1 (sPD-L1), soluble PD-1 (sPD-1), and their combinations, with the area under the curve (AUC) evaluating predictive accuracy. Results: Levels of WFDC2 pre-ICI and those after two cycles were significantly higher than levels in healthy donors. However, no significant differences in WFDC2 levels were found between the time points during treatment. Greater increases in WFDC2 levels were significantly correlated with shorter OS (p = 0.002), shorter PFS (p = 0.037), and tumor progression (p = 0.003). ROC analysis revealed that WFDC2 achieved a higher AUC (0.700) than sPD-L1 (0.538) or sPD-1 (0.650). Combining biomarkers improved the predictive accuracy, with sPD-L1 plus WFDC2 showing the highest AUC (0.825). Conclusions: Serial increases in plasma WFDC2 are associated with poor clinical outcomes, highlighting its potential as a biomarker. Baseline plasma WFDC2 outperformed sPD-L1 and sPD-1 diagnostically. These findings should be interpreted as exploratory and hypothesis-generating, requiring confirmation in larger, tumor-specific cohorts with multivariate adjustment. WFDC2 represents a promising minimally invasive biomarker for the early identification of patients unlikely to benefit from ICI therapy. Full article

The resistance of breast cancer cells to therapeutic antibodies such as anti-HER2 trastuzumab can be overcome by engaging natural killer (NK) cells for killing antibody-binding tumor cells via antibody-dependent cellular cytotoxicity (ADCC). Here, we investigated how autophagy modulation affects trastuzumab-mediated ADCC in HER2-positive JIMT1 breast cancer cells and NK cells. Autophagy inducers (rapamycin and resveratrol) had no significant impact, but the inhibitor bafilomycin nearly abolished ADCC. Protection occurred when either cancer or NK cells were pretreated, indicating dual effects. Bafilomycin reduced phosphatidylserine externalization, the loss of plasma membrane integrity, caspase-3/7 activity, and DNA fragmentation. It downregulated pro-apoptotic BAK1 and BAX without altering BCL-2. Additionally, bafilomycin decreased HER2 surface expression, impairing trastuzumab binding, and modulated immune regulators (STAT1, CD95, and PD-L1) in NK and/or in the cancer cells. Bafilomycin disrupted HER2 trafficking and induced HER2 internalization, leading to its accumulation in cytoplasmic vesicles. These findings show that autophagy inhibition by bafilomycin confers ADCC resistance by altering apoptosis, immune signaling, and HER2 dynamics. The study underscores autophagy’s role in antibody-based cancer therapy efficacy. Full article

Recombinantly produced monoclonal antibodies (mabs) belong to the fastest growing class of biotherapeutics. In humans, antibodies are classified into five different classes: IgA, IgD, IgE, IgG and IgM. Most of the therapeutic mabs used in the clinic belong to the IgG class, albeit other antibody classes, e.g., IgM, have been evaluated in clinical stages. Antibodies are composed of heavy chains paired with a light chain. In IgM and IgA, an additional chain, the J-chain, is present. Two types of light chains exist in humans: the κ-light chain and the λ-light chain. The κ-light chain predominates in humans and is used in the vast majority of therapeutic IgG. The reason for the preference of the κ-light chain in humans is not known. Our study investigates whether light-chain selection influences the productivity of the clinically validated mabs adalimumab and trastuzumab. Both mabs were expressed as IgG and IgM with a κ- or a λ-light chain in HEK293 cells. Besides comparing the expression levels of the different mabs, we also evaluated whether the passage number of the cell line has an impact on product yield. In addition, the expressions of adalimumab, trastuzumab, an anti-CD38 and an anti-PD-L1-antibody were analyzed in HEK293 and CHO cells when both the κ- and λ-light chains are present. In summary, IgG outperformed IgM variants in expression efficacy, while light-chain selection had minimal impact on the overall expression levels. The yields of all mab variants were higher in fresh cells, despite cell cultures with a high cell passage number having higher cell densities and cell numbers at the time of harvest. The incorporation of a particular light chain occurred at similar rates in HEK293 and CHO cells. Full article

Background/Objective: Noninvasive PET imaging-based assessment of PD-L1 expression is of high clinical value for better patient selection and treatment response rates to PD-L1 immunotherapies. Due to their shorter biological half-life and faster clearance from the blood pool, radiolabeled antibody fragments are an attractive alternative for imaging than their full-length IgG counterpart. This work investigated the radiosynthesis and in vitro cell uptake of anti-PD-L1-B11-nanobody radiolabeled with ⁴⁴Sc (t_1/2 = 4.04 h) as an alternative to anti-PD-L1-B11-IgG, better suited for longer half-life radioisotopes such as ⁸⁹Zr (t_1/2 = 78.41 h). Methods: The proteins were conjugated with p-SCN-Bn-DTPA and radiolabeled at room temperature with ⁴⁴Sc, achieving a radiochemical yield of a RCY of 94.8 ± 3.1% (n = 3) for [⁴⁴Sc]Sc-B11-IgG and 73.6 ± 12.1% (n = 3) for [⁴⁴Sc]Sc-B11-nanobody, before purification. Results: Significantly higher uptake in the PD-L1₊ cells than PD-L1_KO cells was observed for both probes. However, high non-specific uptake, particularly of the radiolabeled B11-nanobody, was also observed which may negatively impact its potential as a molecular imaging probe. Conclusions: Due to the high non-specific uptake in vitro, the ⁴⁴Sc radiolabeled nanobody was not progressed to further in vivo evaluation. These results should, however, not discourage future evaluations of other nanobody based probes radiolabeled with ⁴⁴Sc, due to their well-matched biological and physical half-life. Full article

Background: A novel and highly effective strategy for tumor immunotherapy involves enhancing host immune responses against tumors through the blockade of checkpoint molecules. The most common toxicities associated with checkpoint blockade therapies include autoimmune damage to various organs. Purpose: This study aims to investigate hematological markers derived from complete blood counts (CBCs)—including the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), derived neutrophil-to-lymphocyte ratio (dNLR), white blood cell-to-hemoglobin ratio (WHR), neutrophils, lymphocytes, platelets, hemoglobin, red blood cell (RBC) count, neutrophil-to-RBC ratio (NRR), and neutrophil-to-hemoglobin ratio (NHR)—as potential prognostic biomarkers for the early identification of hypothyroidism in patients receiving PD-1 or PD-1/CTLA-4 immune checkpoint inhibitors. Materials and Methods: A prospective observational study was conducted on 44 patients with stage III-IV solid tumors treated with immune checkpoint (PD-1 or PD-1/CTLA-4) inhibitors. Thyroid function tests and CBC-derived biomarkers were collected at baseline, before immunotherapy. In the immunotherapy cohort, 15 of the 44 patients developed immune-related hypothyroidism, defined as overt autoimmune thyroiditis (TSH > 4.0, FT4 < 12, and anti-TPO antibodies > 30 IU/mL and/or anti-TG antibodies > 95 IU/mL) (Group 1). In comparison, 29 patients maintained normal thyroid function (Group 2). The control group comprised 14 age- and sex-matched healthy volunteers (Group 3). Statistical analyses were performed using analysis of variance (ANOVA) to compare blood parameters among the three groups (Group 1, Group 2, and Group 3) before treatment, with statistical significance set at a p-value < 0.05. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the diagnostic power of the potential prognostic biomarkers areas. The area under the curve (AUC), sensitivity, and specificity were calculated for the 44 immunotherapy patients. Results: The PLR was significantly higher (262.25 ± 162.95), while WBCs-neutrophils, the WHR, the NRR, the NHR, WBCs, neutrophils, and lymphocytes were lower (2.07 ± 0.66, 0.54 ± 0.19, 0.96 ± 0.28, 0.36 ± 0.14, 6.36 ± 2.07, 4.29 ± 1.55, and 1.23 ± 0.41, respectively) at baseline in Group 1 in comparison to Group 2. ROC curve analysis revealed that the areas under the curve (AUC) for WBCs, neutrophils, lymphocytes, WBCs-neutrophils, the PLR, the WHR, the NRR, and the NHR were 0.9, 0.87, 0.83, 0.85, 0.84, 0.92, 0.89, and 0.87, respectively. These values exceeded the threshold, indicating the high prognostic potential of each marker. Conclusions: Lower baseline levels of WBCs-neutrophils, the WHR, the NRR, the NHR, WBCs, neutrophils, and lymphocytes, along with a higher PLR, were associated with an increased risk of hypothyroidism in patients receiving PD-1 or PD-1/CTLA-4 inhibitors. These CBC-derived biomarkers represent simple, accessible, and potentially useful tools for predicting hypothyroidism in cancer patients undergoing immunotherapy. Further studies in bigger cohorts are needed to validate our findings. Full article

Triple-negative breast cancer (TNBC) is a highly aggressive form of breast cancer. Common treatments following surgical resection include PD-1-targeting checkpoint inhibitors (pembrolizumab), as 20% of tumors are PD-L1 positive with or without systemic chemotherapy. Over the last several years, our laboratory has developed nano-immune conjugates (NIC) in which hydrophobic chemotherapy drugs like paclitaxel (PTX) and SN38, the active metabolite of irinotecan, are made water soluble by formulating them into albumin-based nanoparticles (nab) that are hydrophobically linked to various IgG1 monoclonal antibodies, creating an antigen-targetable nano-immune conjugate. To date, we have successfully tested PTX containing NICs linked to either VEGF- or CD20-targeted antibodies in two phase I clinical trials against multiple relapsed ovarian/uterine cancer or non-Hodgkin’s lymphoma, respectively. Herein, we describe a novel NIC created with either PTX or SN38 that is coated with anti-PD-L1-targeting antibodies for the treatment of a preclinical model of TNBC. In vitro testing suggests that the chemotherapy drug and antibody retain their toxicity and ligand binding capability in the context of the NIC. Furthermore, both the PTX and SN-38 NIC demonstrate superior anti-tumor efficacy relative to antibody and chemotherapy drugs alone in a PD-L1 + MDA-MB-231 human TNBC xenograft model, which could translate clinically to patients with TNBC. Full article