PD-L1 Pathway Research Articles

CD39 delineates chimeric antigen receptor regulatory T cell subsets with distinct cytotoxic & regulatory functions against human islets.

Human regulatory T cells (Treg) suppress other immune cells. Their dysfunction contributes to the pathophysiology of autoimmune diseases, including type 1 diabetes (T1D). Infusion of Tregs is being clinically evaluated as a novel way to prevent or treat T1D. Genetic modification of Tregs, most notably through the introduction of a chimeric antigen receptor (CAR) targeting Tregs to pancreatic islets, may improve their efficacy. We evaluated CAR targeting of human Tregs to monocytes, a human β cell line and human islet β cells in vitro. Targeting of HLA-A2-CAR (A2-CAR) bulk Tregs to HLA-A2+ cells resulted in dichotomous cytotoxic killing of human monocytes and islet β cells. In exploring subsets and mechanisms that may explain this pattern, we found that CD39 expression segregated CAR Treg cytotoxicity. CAR Tregs from individuals with more CD39low/- Tregs and from individuals with genetic polymorphism associated with lower CD39 expression (rs10748643) had more cytotoxicity. Isolated CD39- CAR Tregs had elevated granzyme B expression and cytotoxicity compared to the CD39+ CAR Treg subset. Genetic overexpression of CD39 in CD39low CAR Tregs reduced their cytotoxicity. Importantly, β cells upregulated protein surface expression of PD-L1 and PD-L2 in response to A2-CAR Tregs. Blockade of PD-L1/PD-L2 increased β cell death in A2-CAR Treg co-cultures suggesting that the PD-1/PD-L1 pathway is important in protecting islet β cells in the setting of CAR immunotherapy. In summary, introduction of CAR can enhance biological differences in subsets of Tregs. CD39+ Tregs represent a safer choice for CAR Treg therapies targeting tissues for tolerance induction.

Exploring novel immunotherapy biomarker candidates induced by cancer deformation.

Triple-negative breast cancer (TNBC) demands urgent attention for the development of effective treatment strategies due to its aggressiveness and limited therapeutic options [1]. This research is primarily focused on identifying new biomarkers vital for immunotherapy, with the aim of developing tailored treatments specifically for TNBC, such as those targeting the PD-1/PD-L1 pathway. To achieve this, the study places a strong emphasis on investigating Ig genes, a characteristic of immune checkpoint inhibitors, particularly genes expressing Ig-like domains with altered expression levels induced by "cancer deformation," a condition associated with cancer malignancy. Human cells can express approximately 800 Ig family genes, yet only a few Ig genes, including PD-1 and PD-L1, have been developed into immunotherapy drugs thus far. Therefore, we investigated the Ig genes that were either upregulated or downregulated by the artificial metastatic environment in TNBC cell line. As a result, we confirmed the upregulation of approximately 13 Ig genes and validated them using qPCR. In summary, our study proposes an approach for identifying new biomarkers applicable to future immunotherapies aimed at addressing challenging cases of TNBC where conventional treatments fall short.

TCCIA: a comprehensive resource for exploring CircRNA in cancer immunotherapy

BackgroundImmunotherapies targeting immune checkpoints have gained increasing attention in cancer treatment, emphasizing the need for predictive biomarkers. Circular RNAs (circRNAs) have emerged as critical regulators of tumor immunity, particularly in...

Inhibition of α4β1 Integrin Activity by Small Tellurium Compounds Regulates PD-L1 Expression and Enhances Antitumor Effects.

Various cancer treatment approaches that inhibit the activity of the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) axis, a key player in tumor immune evasion, have been developed. We show that the immunomodulatory small tellurium complexes AS101 (ammonium trichloro(dioxoethylene-o,o')tellurate) and SAS (octa-O-bis(R,R)-tartarate ditellurane) suppress PD-L1 expression in a variety of human and mouse malignant cells via the modulation of α4β1 very late antigen-4 (VLA-4) integrin activity. Consequently, the expression of pAkt and its downstream effector pNFκB are inhibited. Additionally, SAS promotes the death of mouse malignant cells by activated syngeneic splenocytes or CD8+ T cells, preventing the development of chemoresistance in malignant cells. Moreover, AS101 and SAS may increase, at least in part, chemosensitivity through inhibition of the VLA-4/IL-10/PD-L1 pathway. Additionally, AS101 or SAS treatment of B16/F10 melanoma-bearing mice decreased tumor cell PD-L1 expression, leading to increased CD8+ T-cell infiltration into the tumors and tumor shrinkage. Combination treatment with an αPD-1 antibody and either tellurium compound significantly increased the antitumor efficacy of immunotherapy. Overall, VLA-4 integrin signaling is critical for tumor immune evasion and is a potential target for cancer treatment. Finally, AS101 or SAS, biologically active tellurium compounds, can effectively enhance the therapeutic efficacy of αPD-1-based cancer immunotherapy.

An updated review of immunotherapy in esophageal cancer: PD-L1 footprint.

Esophageal cancer is considered one of the most significant challenges to public health worldwide. While various therapeutic options exist for esophageal cancer, including chemotherapy, radiotherapy, and surgery, several adverse effects of these medications have been reported. Therefore, a new generation of therapeutic lines should be applied to minimize complications. In this regard, immunotherapy is a novel approach that aims to kill tumor cells directly by targeting them. Specifically, monoclonal antibodies can target specific markers of esophageal cancer tumor cells, keeping other normal cells safe. Multiple monoclonal antibodies optimized for esophageal cancer, such as pembrolizumab, ramucirumab, trastuzumab, nivolumab, and ipilimumab, are available. On the other hand, esophageal cancer tumor cells express a specific inhibitory ligand and its receptor called programmed cell death, which can suppress T cell immune responses. This receptor provides an inhibitory signal, causing the highest expression of the PD-L1 ligand on tumor cells. The outcomes of this interaction lead to the suppression of the activation and function of T lymphocytes. Therefore, immunotherapy for esophageal cancer targeting the PD-1/PD-L1 pathway has shown a remarkable correlation with cancer care. This study presents a comprehensive review of the latest findings related to immunotherapy in esophageal cancer.

An advanced comprehensive muti-cell-type-specific model for predicting anti-PD-1 therapeutic effect in melanoma.

Rationale: Immune checkpoint inhibitors targeting the programmed cell death (PD)-1/PD-L1 pathway have promise in patients with advanced melanoma. However, drug resistance usually results in limited patient benefits. Recent single-cell RNA sequencing studies have elucidated that MM patients display distinctive transcriptional features of tumor cells, immune cells and interstitial cells, including loss of antigen presentation function of tumor cells, exhaustion of CD8+T and extracellular matrix secreted by fibroblasts to prevents immune infiltration, which leads to a poor response to immune checkpoint inhibitors (ICIs). However, cell subgroups beneficial to anti-tumor immunity and the model developed by them remain to be further identified. Methods: In this clinical study of neoadjuvant therapy with anti-PD-1 in advanced melanoma, tumor tissues were collected before and after treatment for single-nucleus sequencing, and the results were verified using multicolor immunofluorescence staining and public datasets. Results: This study describes four cell subgroups which are closely associated with the effectiveness of anti-PD-1 treatment. It also describes a cell-cell communication network, in which the interaction of the four cell subgroups contributes to anti-tumor immunity. Furthermore, we discuss a newly developed predictive model based on these four subgroups that holds significant potential for assessing the efficacy of anti-PD-1 treatment. Conclusions: These findings elucidate the primary mechanism of anti-PD-1 resistance and offer guidance for clinical drug administration for melanoma.

Beyond the Scalpel: Advancing Strategic Approaches and Targeted Therapies in Nonexcisable Melanomas.

Melanoma in challenging anatomical locations such as the face, acral surfaces, and mucosal areas presents unique hurdles for surgical excision. This review examines alternative nonsurgical treatment modalities in the context of these complexities, addressing the gaps in current guidelines and the varied efficacy of existing therapies. A comprehensive literature search was conducted using PubMed, Embase, and Web of Science databases. The review focuses on peer-reviewed articles discussing nonsurgical treatment options for melanoma in complex anatomical locations. Articles were screened by three independent researchers, ensuring a broad analysis of topical agents, immunotherapies, radiotherapies, and targeted therapies. The review highlights significant advancements in localized treatments such as imiquimod and intralesional therapy with talimogene laherparepvec (T-VEC), which show promise in managing nonexcisable melanomas. BRAF and MEK inhibitors, as well as checkpoint inhibitors targeting CTLA-4 and PD-1/PD-L1 pathways, demonstrate improved survival rates but pose challenges with resistance and systemic side effects. Radiotherapy serves as an adjunctive strategy due to melanoma's inherent radioresistant properties. Despite advancements, there is a notable absence of comprehensive, evidence-based protocols to guide the treatment of melanoma in these critical areas. This paper underscores the need for standardized treatment guidelines that account for the efficacy, side effects, and psychosocial impacts of therapies. Future research should focus on refining existing treatments and exploring innovative modalities to enhance patient outcomes in the management of nonexcisable melanomas. Comprehensive guidelines and long-term efficacy studies are essential to optimize care and improve the quality of life for patients afflicted with melanoma in challenging anatomical locations.

Promoter methylation and increased expression of PD-L1 in patients with active tuberculosis.

The PD-1/PD-L1 pathway plays a pivotal role in T cell activity and is involved in the pathophysiology of Mycobacterium tuberculosis (MTB) infection. DNA methylation is a mechanism that modulates PD-L1 expression in cancer cells. However, its effect on PD-L1 expression in macrophages after MTB infection remains unknown. We prospectively enrolled patients with active tuberculosis (TB) and non-TB subjects. The expression of PD-L1 and methylation-related genes in peripheral blood mononuclear cells (PBMCs) were investigated and their correlation with disease severity and treatment outcomes were examined. PD-L1 promoter methylation status was evaluated using bisulfite sequencing. Immunohistochemistry (IHC) and immunofluorescence (IF) staining were used to visualize PD-L1- and TET-1-expressing cells in lung tissues from patients with TB and in macrophage cell lines with MTB-related stimulation. In total, 80 patients with active TB and 40 non-TB subjects were enrolled in the analysis. Patients with active TB had significantly higher expression of PD-L1, DNMT3b, TET1, TET2, and lower expression of DNMT1, compared to that in the non-TB subjects. The expression of PD-L1 and TET-1 was significantly associated with 1-month smear and culture non-conversion. IHC and IF staining demonstrated the co-localization of PD-L1- and TET-1-expressing macrophages in patients with pulmonary TB and in human macrophage cell lines after MTB-related stimulation. DNMT inhibition and TET-1 knockdown in human macrophages increased and decreased PD-L1 expression, respectively. Overall, PD-L1 expression is increased in patients with active TB and is correlated with treatment outcomes. DNA methylation is involved in modulating PD-L1 expression in human macrophages.

Role Of PD-1 Immune Checkpoint Inhibition in Lung Cancer Treatment

Non-small cell lung cancer (NSCLC) can be distinguished by histopathology and tumor markers. The treatment methods of NSCLC mainly include radiotherapy, chemotherapy, surgical treatment and TCM therapy. PD-1/PD-L1 immunotherapy has an advantage in combination therapy, producing a low-toxic, long-acting antitumor immune response in cancer therapy. This thesis describes the main methods of NSCLC therapy, details the PD-1/PD-L1 pathway and immunotherapy, and studies applications of three monoclonal antibodies in monotherapy and combination therapy. We conclude that the combination therapy has the outstanding advantage of safety, mild effect and prediction, but the problem of drug resistance to PD-1/PD-L1 needs to be solved urgently.

The multiple arrays of a PD1-derived peptide on chromatin specifically bind to PD-L1 and induce doxorubicin resistance in cancer cell lines

Programmed cell death-1 (PD-1) and its ligand 1 (PD-L1) have been extensively studied to block the activation of the PD-1 axis immune checkpoint pathway on T cells. However, recent evidence suggests that PD-1-independent PD-L1 pathways in cancer cells and macrophages are important in cellular proliferation and survival of those cell types but the underlying mechanism is little understood. To recapitulate the binding of multiple PD-1 to the high levels of PD-L1 expression on cancer cell membranes, recombinant histones carrying a PD-1 receptor-derived peptide (PDR) were prepared and used to assemble a PDR-displayed nucleosome array. PDR-displayed chromatin showed physiologically spaced nucleosomes, unaffected by N-terminal histone tails and biotinylated DNA modifications. PDR-displayed chromatin exhibited selective binding to the breast cancer cell line with high PD-L1 expression, MDA-MB-231, where saturated binding occurred within 3 h, comparable to well-known antigen-antibody reactions. Notably, PDR-displayed chromatin enhanced resistance to doxorubicin in PD-L1-overexpressed cancer cells, revealing a PD-L1 level-dependent effect on cell survival upon chemotherapy. Our study sheds light on the potential of PDR-displayed chromatin as a tool to induce chemoresistance in cancer cells without employing anti-PD-L1 antibodies or soluble PD-1 receptors. Further investigation into the underlying signaling pathways and therapeutic applications is warranted, positioning PDR-displayed chromatin as a valuable tool for understanding PD-L1-mediated intracellular signaling pathways in cancer cells with high PD-L1 expression.

The implication of targeting PD-1:PD-L1 pathway in treating sepsis through immunostimulatory and anti-inflammatory pathways.

Sepsis currently remains a major contributor to mortality in the intensive care unit (ICU), with 48.9 million cases reported globally and a mortality rate of 22.5% in 2017, accounting for almost 20% of all-cause mortality worldwide. This highlights the urgent need to improve the understanding and treatment of this condition. Sepsis is now recognized as a dysregulation of the host immune response to infection, characterized by an excessive inflammatory response and immune paralysis. This dysregulation leads to secondary infections, multiple organ dysfunction syndrome (MODS), and ultimately death. PD-L1, a co-inhibitory molecule expressed in immune cells, has emerged as a critical factor in sepsis. Numerous studies have found a significant association between the expression of PD-1/PD-L1 and sepsis, with a particular focus on PD-L1 expressed on neutrophils recently. This review explores the role of PD-1/PD-L1 in immunostimulatory and anti-inflammatory pathways, illustrates the intricate link between PD-1/PD-L1 and sepsis, and summarizes current therapeutic approaches against PD-1/PD-L1 in the treatment and prognosis of sepsis in preclinical and clinical studies.

Membrane (CD8⁺PD-1⁺ and CD4+PD-1⁺) and soluble (sPD-1 and sPD-L1) forms of immune checkpoints in melanoma, breast cancer, and oral mucosal cancer patients: A observational study

Background. The PD-1/PD-L1 pathway plays an important role in tumor evasion from immunological surveillance. In addition to the membrane forms of PD-1 and PD-L1, there are soluble variants: sPD-1 and sPD-L1. Both membrane and soluble forms have immunoregulatory properties and can affect the function and number of different immune cell populations.
 Aim. To study the relationship between the initial level of CD8⁺PD-1⁺ and CD4+PD-1⁺ lymphocytes and soluble forms of sPD-1 and sPD-L1 with the percentage of the main effector and regulatory populations of peripheral blood (PB) lymphocytes and tumor-infiltrating lymphocytes.
 Materials and methods. The study included melanoma, breast cancer and the oral mucosa cancer patients. The percentage of cell populations of PB lymphocytes and tumor-infiltrating lymphocytes was determined by flow cytometry before treatment. The concentrations of sPD-1 and sPD-L1 proteins were studied in blood serum using enzyme immunoassay.
 Results. The relationship of the level of CD8⁺PD-1⁺ cells with certain populations of CD8-lymphocytes in PB and tumor tissue was found. In the PB of melanoma patients with CD8⁺CD11b⁺CD28⁺ and CD8⁺CD11b⁻CD28⁻ T cells, in breast cancer patients with a population of CD8⁺CD11b⁺CD28⁺ lymphocytes. In the tumor tissue of all patients there was a positive correlation with a population of regulatory CD8⁺CD11b⁻CD28⁻ T cells. The immunoregulatory properties of sPD-1 and sPD-L1 were confirmed. Both sPD-1 and sPD-L1 levels were positively correlated with the number of suppressor CD8⁺CD11b⁻CD28⁻ T cells and negatively with the level of CD8 lymphocytes, CD8⁺CD11b⁺CD28⁺ cytotoxic/memory T cells, B cells and activated CD25 lymphocytes.
 Conclusion. The results of the study can make a certain contribution to the study of the prognostic significance of membrane and soluble forms of PD-1 and PD-L1, taking into account the peculiarities of their relationship with suppressor and effector populations of lymphocytes of systemic and local immunity.

Bispecific antibodies revolutionizing breast cancer treatment: a comprehensive overview.

Breast cancer (BCa) is known as a complex and prevalent disease requiring the development of novel anticancer therapeutic approaches. Bispecific antibodies (BsAbs) have emerged as a favorable strategy for BCa treatment due to their unique ability to target two different antigens simultaneously. By targeting tumor-associated antigens (TAAs) on cancer cells, engaging immune effector cells, or blocking critical signaling pathways, BsAbs offer enhanced tumor specificity and immune system involvement, improving anti-cancer activity. Preclinical and clinical studies have demonstrated the potential of BsAbs in BCa. For example, BsAbs targeting human epidermal growth factor receptor 2 (HER2) have shown the ability to redirect immune cells to HER2-positive BCa cells, resulting in effective tumor cell killing. Moreover, targeting the PD-1/PD-L1 pathway by BsAbs has demonstrated promising outcomes in overcoming immunosuppression and enhancing immune-mediated tumor clearance. Combining BsAbs with existing therapeutic approaches, such as chemotherapy, targeted therapies, or immune checkpoint inhibitors (ICIs), has also revealed synergistic effects in preclinical models and early clinical trials, emphasizing the usefulness and potential of BsAbs in BCa treatment. This review summarizes the latest evidence about BsAbs in treating BCa and the challenges and opportunities of their use in BCa.

Advances in tumor immunomodulation based on nanodrug delivery systems.

Immunotherapy is a therapeutic approach that employs immunological principles and techniques to enhance and amplify the body's immune response, thereby eradicating tumor cells. Immunotherapy has demonstrated effective antitumor effects on a variety of malignant tumors. However, when applied to humans, many immunotherapy drugs fail to target lesions with precision, leading to an array of adverse immune-related reactions that profoundly limit the clinical application of immunotherapy. Nanodrug delivery systems enable the precise delivery of immunotherapeutic drugs to targeted tissues or specific immune cells, enhancing the immune antitumor effect while reducing the number of adverse reactions. A nanodrug delivery system provides a feasible strategy for activating the antitumor immune response by the following mechanisms: 1) increased targeting and uptake of vaccines by DCs, which enhances the efficacy of the immune response; 2) increased tumor cell immunogenicity; 3) regulation of TAMs and other cells by, for example, regulating the polarization of TAMs and interfering with TAN formation, and ECM remodeling by CAFs; and 4) interference with tumor immune escape signaling pathways, namely, the PD-1/PD-L1, FGL1/LAG-3 and IDO signaling pathways. This paper reviews the progress of nanodrug delivery system research with respect to tumor immunotherapy based on tumor immunomodulation over the last few years, discussing the promising future of these delivery systems under this domain.

Anti-PD-1/PD-L1 therapy for colorectal cancer: Clinical implications and future considerations

Colorectal cancer (CRC) is the third most prevalent cancer in the world. The PD-1/PD-L1 pathway plays a crucial role in modulating immune response to cancer, and PD-L1 expression has been observed in tumor and immune cells within the tumor microenvironment of CRC. Thus, immunotherapy drugs, specifically checkpoint inhibitors, have been developed to target the PD-1/PD-L1 signaling pathway, thereby inhibiting the interaction between PD-1 and PD-L1 and restoring T-cell function in cancer cells. However, the emergence of resistance mechanisms can reduce the efficacy of these treatments. To counter this, monoclonal antibodies (mAbs) have been used to improve the efficacy of CRC treatments. mAbs such as nivolumab and pembrolizumab are currently approved for CRC treatment. These antibodies impede immune checkpoint receptors, including PD-1/PD-L1, and their combination therapy shows promise in the treatment of advanced CRC. This review presents a concise overview of the use of the PD-1/PD-L1 blockade as a therapeutic strategy for CRC using monoclonal antibodies and combination therapies. Additionally, this article outlines the function of PD-1/PD-L1 as an immune response suppressor in the CRC microenvironment as well as the potential advantages of administering inflammatory agents for CRC treatment. Finally, this review analyzes the outcomes of clinical trials to examine the challenges of anti-PD-1/PD-L1 therapeutic resistance.

Safety and Preliminary Efficacy of Sabestomig (AZD7789), an Anti-PD-1 and Anti-TIM-3 Bispecific Antibody, in Patients with Relapsed or Refractory Classical Hodgkin Lymphoma Previously Treated with Anti-PD-(L)1 Therapy

Background Immunotherapies targeting the PD-1/PD-L1 pathway have been shown to induce high response rates in patients with relapsed/refractory (r/r) classical Hodgkin lymphoma (cHL). However, most responses are partial and not durable. T cell immunoglobulin and mucin domain-containing protein-3 (TIM-3) is implicated as a resistance mechanism following anti-PD-1 therapy, and increased TIM-3 expression has been observed on T cells of patients with cHL post anti-PD-1 therapy. Therefore, we hypothesized that dual targeting of PD-1 and TIM-3 may reinvigorate immune responses and lead to more durable antitumor activity. Sabestomig is a monovalent, bispecific, humanized IgG1 monoclonal antibody that binds PD-1 and a unique epitope in the TIM-3 IgV domain without blocking phosphatidylserine binding, eliciting differential functionality. In preclinical mouse models, sabestomig was more effective at inhibiting growth of solid tumors than treatment targeting only PD-1, and sequential sabestomig after anti-PD-1 therapy increased antitumor responses. Here we report preliminary data from the ongoing dose escalation portion of a Phase I/II, open-label, multicenter study to assess the safety and preliminary efficacy of sabestomig in patients with r/r cHL (NCT05216835). Methods Eligible patients are aged ≥16 years with r/r cHL, an Eastern Cooperative Oncology Group performance status 0-1, at least one positron emission tomography-avid measurable lesion according to modified Lugano Criteria, and exposure to at least 2 prior lines of systemic therapy including a minimum of 3 cycles of an anti-PD-(L)1-based therapy. Sabestomig is intravenously infused over 1 hour following pretreatment with diphenhydramine and acetaminophen every 3 weeks, with planned doses ranging from 2 to 2000 mg across 8 cohorts (A1-A8); cohorts A1 to A4 (2, 7, 22.5 or 75 mg) follow an accelerated titration design with a single patient treated at each dose level, while cohorts A5 to A8 (225-2000 mg) follow a modified toxicity probability interval-2 algorithm. The primary endpoint of the dose escalation part of the study is safety, including dose-limiting toxicities (DLTs). Secondary endpoints include efficacy, pharmacokinetics, and immunogenicity. Data cutoffs were May 17, 2023 for safety and June 20, 2023 for efficacy. Results As of May 17, 2023, 14 patients were treated across the first 6 cohorts (A1-A6; 2-750 mg). They were predominantly male (64.3%) with Stage IV disease (85.7%) and a median age of 41.5 years (range, 25-77). Patients received a median of 6 prior lines of therapy (range, 3-13). Baseline disease characteristics are summarized in Table 1. Four patients received sabestomig 2-75 mg in cohorts A1-A4 (n=1 each), 5 patients received 225 mg in cohort A5, and 5 patients received 750 mg in cohort A6. Median duration of exposure to sabestomig was 8.9 weeks (range, 3.0-34.3) with a median of 3 cycles received (range 1-12). Sabestomig was well tolerated with no Grade ≥3 treatment-related adverse events (AEs) (Table 2). One Grade ≥3 AE occurred, which was fatal (sepsis secondary to gastric ulcer rupture, not related to sabestomig but deemed a DLT by the safety review committee). No immune-mediated AEs were reported, and no AEs led to treatment discontinuation. At the safety data cutoff, treatment was ongoing for 6 patients (42.9%). As of June 20, 2023, 11 patients had their first disease assessment and 4/11 had an objective response based on modified Lugano Criteria: 1 patient in cohort A3 (22.5 mg, a partial response [PR]) and all 3 patients who had their first disease assessment in cohort A6 (750 mg, 2 CRs and 1 PR). Two of these 4 responders (both in cohort A6) had experienced a best overall response of progressive disease during prior anti-PD-1 therapy; the other two initially had a response (1 CR [cohort A6] and 1 PR [cohort A3]) but subsequently progressed on anti-PD-1 therapy. Sustained PD-1 receptor occupancy (≥90%) was observed in peripheral blood at doses ≥225 mg. Conclusions Sabestomig was well tolerated with a manageable safety profile. Early efficacy data at 750 mg is encouraging with objective responses in 3/3 patients who had their first disease assessment, including those who were anti-PD-1 refractory or who relapsed on treatment. Updated data will be presented from ongoing and subsequent patients treated during dose escalation with doses of up to 2000 mg.

Anti-PD-1 Antibody Sintilimab in Combination with Anlotinib and Pegaspargase As a Highly Effective Salvage Regimen for the Treatment of Relapsed or Refractory Natural Killer /T-Cell Lymphoma

Natural killer/T-cell lymphoma (NKTCL) is a rare and aggressive neoplasm associated with Epstein-Barr virus (EBV) infection. When patients experience relapse or disease progression after initial treatment, options for salvage therapy are limited. Targeting the PD-1/PD-L1 pathway has emerged as a highly potent treatment approach for NKTCL. However, the overall response rate (ORR) and complete response (CR) rate were limited with a short median progression-free survival (PFS) of 2.7 months. Therefore, improving the efficacy of immune checkpoint inhibitors is a critical clinical concern. In this study, we reported the efficacy and safety of a novel triplet regimen called LEAP, which combines PD-1 blockade (sintilimab 200mg on day 1), pegaspargase (2500U/m2 capped at 3750U on day 1), and angiogenesis inhibitor anlotinib (8mg on day 1-14), as a salvage treatment for relapsed/refractory (R/R) NKTCL. From March 2019 to May 2020, a total of 33 patients with R/R NKTCL were included in this study. The median age of patients was 48 years (range: 18-76), with 75.8% being male. At study entry, 88% of patients had stage IV disease, while 4 patients had stage II disease, with a history of primary refractory response to radiotherapy and L-asparaginase-based combination therapy. Moreover, 69.7% of patients had refractory disease, including those who were progressive or non-responsive to L-asparaginase-based regimens. Additionally, 10 patients experienced relapse or disease progression within 6 months after prior L-asparaginase-based therapy, and 10 patients had a history of PD-1/PD-L1 blockade monotherapy. A total of 221 cycles of the LEAP regimen were administered to these patients. The median number of cycles was 8 (range: 2-8). All patients reported at least one or more adverse events (AE). Hematological toxicities were mild, with no grade 3/4 neutropenia, anemia, or thrombocytopenia observed. Non-hematological AEs were common, and the most frequent (>20%) included hypofibrinogenemia (66.7%), hyperbilirubinemia (57.5%), APTT prolongation (54.5%), ALT elevation (54.5%), AST elevation (51.5%), hypoalbuminemia (48.5%), appetite loss (60.6%), nausea (57.5%), fatigue (57.5%), weight loss (42.4%), and edema (27.3%). These adverse events were typically attributed to pegaspargase. Other adverse events such as hyponatremia (24.2%), hypertriglyceridemia (21.2%), hyperglycemia (21.2%), hypothyroidism (30.3%), hypertension (24.2%), fever (39.4%), and dysphonia (21.2%) were most likely due to sintilimab or anlotinib. Most adverse events were manageable with supportive care. Among the 33 patients, the ORR was 81.8%, and CR was 45.5. The progression-free survival (PFS) rate at 1-year was 54.6% (95% CI, 36.3% to 70.0%), and at 2 years, it was 44.2% (95% CI, 26.6% to 60.4%). The median PFS time was 21.7 months. The overall survival (OS) rate at 1-year was 66.7% (95% CI, 47.9% to 80.0%), and at 2 years, it was 51.5% (95% CI, 33.5% to 66.9%). The median OS time was not reached during the study period. In conclusion, our study demonstrates that the LEAP regimen has a favorable safety profile, and is highly effective as a salvage treatment for patients with relapsed and refractory NKTCL.

Overcoming Immune Checkpoint Therapy Resistance with SHP2 Inhibition in Cancer and Immune Cells: A Review of the Literature and Novel Combinatorial Approaches.

SHP2 (Src Homology 2 Domain-Containing Phosphatase 2) is a protein tyrosine phosphatase widely expressed in various cell types. SHP2 plays a crucial role in different cellular processes, such as cell proliferation, differentiation, and survival. Aberrant activation of SHP2 has been implicated in multiple human cancers and is considered a promising therapeutic target for treating these malignancies. The PTPN11 gene and functions encode SHP2 as a critical signal transduction regulator that interacts with key signaling molecules in both the RAS/ERK and PD-1/PD-L1 pathways; SHP2 is also implicated in T-cell signaling. SHP2 may be inhibited by molecules that cause allosteric (bind to sites other than the active site and attenuate activation) or orthosteric (bind to the active site and stop activation) inhibition or via potent SHP2 degraders. These inhibitors have anti-proliferative effects in cancer cells and suppress tumor growth in preclinical models. In addition, several SHP2 inhibitors are currently in clinical trials for cancer treatment. This review aims to provide an overview of the current research on SHP2 inhibitors, including their mechanism of action, structure-activity relationships, and clinical development, focusing on immune modulation effects and novel therapeutic strategies in the immune-oncology field.

A phase I study of the combination of atezolizumab, tiragolumab, and stereotactic body radiation therapy in patients with metastatic multiorgan cancer

BackgroundImmunotherapy targeting the PD-1/PD-L1 pathway is a standard of care in a number of metastatic malignancies, but less than a fifth of patients are expected to respond to ICIs (Immune Checkpoint Inhibitors). In a clinical trial, combining the anti-TIGIT (T cell immunoreceptor with Ig and ITIM domains) Mab (monoclonal antibody) tiragolumab with atezolizumab improved outcomes in non-small cell lung cancer. In preclinical models, SBRT (Stereotactic Body Radiation Therapy) could increase expression levels of the inhibitory co-receptors TIGIT and PD-L1. We aim to assess the combination of tiragolumab with atezolizumab and SBRT in metastatic, previously treated by ICIs, non-small cell lung cancer, head and neck cancer, bladder cancer, and renal cell cancer.MethodsThis phase I study (ClinicalTrials.gov NCT05259319) will assess the efficacy and safety of the combination of atezolizumab with tiragolumab and stereotactic body radiation therapy in patients with histologically proven metastatic non-small cell lung cancer, renal cell cancer, bladder cancer, and head and neck cancer previously treated. First part: 2 different schedules of SBRT in association with a fixed dose of atezolizumab and tiragolumab will be investigated only with metastatic non-small cell lung cancer patients (cohort 1). The expansion cohorts phase will be a multicentric, open-label study at the recommended scheme of administration and enroll additional patients with metastatic bladder cancer, renal cell cancer, and head and neck cancer (cohort 2, 3 and 4). Patients will be treated until disease progression, unacceptable toxicity, intercurrent conditions that preclude continuation of treatment, or patient refusal in the absence of progression or intolerance. The primary endpoint of the first phase is the safety of the combination in a sequential or concomitant scheme and to determine the expansion cohorts phase recommended scheme of administration. The primary endpoint of phase II is to evaluate the efficacy of tiragolumab + atezolizumab + SBRT in terms of 6-month PFS (Progression-Free Survival). Ancillary analyses will be performed with peripheral and intratumoral immune biomarker assessments.Trial registrationThis study is registered on ClinicalTrials.gov: NCT05259319, since February 28th, 2022.

Efficacy, safety, and correlative biomarkers of bintrafusp alfa in recurrent or metastatic nasopharyngeal cancer patients: a phase II clinical trial.

The strategy of dual blockade of TGF-β and PD-L1 pathways has not been previously tested in platinum-refractory recurrent or metastatic nasopharyngeal cancer (R/M NPC) patients. This study aimed to evaluate the safety and efficacy of bintrafusp alfa in refractory R/M NPC patients. In this single-arm, single-centre phase II clinical trial, 38 histologically confirmed R/M NPC patients were enrolled and administered with bintrafusp alfa every 2 weeks. Primary endpoint was objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). Secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response (DOR), and safety. Thirty-eight patients were accrued (33 men; median age, 54 years). ORR was 23.7% (complete response, n=2; partial response, n=7). The median DOR was 19.2 months, median PFS was 2.3 months, median OS was 17.0 months, and 1-year OS rate was 63.2%. Unfortunately, 25 patients (65.7%) progressed within 8 weeks of treatment, 15 patients (39.5%) and 8 patients (21.1%) developed hyper-progressive disease (HPD) per RECIST v1.1 and tumor growth rate (TGR) ratio respectively. Sixteen patients (42.4%) experienced≥grade 3 treatment-related adverse events (TRAEs), most commonly anemia (n=9, 23.7%) and secondary malignancies (n=4, 10.5%). TRAEs led to permanent treatment discontinuation in 7 patients. Patients with strong suppression of plasma TGFβ1 level at week 8 were unexpectedly associated with worse ORR (9.1% vs 44.4%, P=0.046) and development of HPD. There was no correlation between PD-L1 expression and ORR. Bintrafusp alfa demonstrated modest activity in R/M NPC but high rates of HPD and treatment discontinuation secondary to TRAEs are concerning. The project was supported by Alice Ho Miu Ling Nethersole Charity Foundation Professorship Endowed Fund and Merck KGaA.