Anti-programmed Death-ligand Research Articles

DNA aptamer-conjugated lipid nanoparticle for targeted PTEN mRNA delivery to prostate cancer cells

The use of messenger RNA (mRNA) as a cancer vaccine and gene therapy requires targeted vehicle delivery to the site of disease. Here, we designed a mRNA-encapsulating lipid nanoparticle (LNP) conjugated with anti-programmed death-ligand 1 (PD-L1) DNA aptamer that delivers mRNA encoding a tumor suppressor gene, namely phosphatase and tensin homolog (PTEN), to castration-resistant prostate cancer (CRPC) cells expressing PD-L1 on the cell surface. The DNA aptamer-conjugated LNP-based mRNA delivery system (Apt-LNP[PTEN mRNA]) mediated efficient mRNA delivery and transfection in CRPC cells than LNPs without targeting ligands. Cancer-targeted PTEN mRNA delivery using Apt-LNPs achieved significantly higher PTEN expression via aptamer-mediated endocytosis in target cancer cells compared with non-targeted LNP delivery, resulting in significant downregulation of AKT phosphorylation. This enhanced PI3K/AKT pathway regulation, and in turn reduced cell migration after two days along with a 70 % decrease in cell viability, leading to effective apoptotic cell death. In a CRPC xenograft model, Apt-LNP[PTEN mRNA] led to an approximate 60 % reduction in tumor growth, which was attributable to the effective PTEN restoration and PI3K/AKT signaling pathway regulation. PTEN expression was significantly enhanced in CRPC tumor tissues, which abolished cancer cell tumorigenicity. These findings demonstrated the potential of Apt-LNPs for targeted mRNA delivery to cancer cells, thus providing a promising tool for targeted mRNA delivery to a range of cancers and tissues using a conventional LNP systems.

Cyclin dependent kinase 9 inhibition reduced programmed death-ligand 1 expression and improved treatment efficacy in hepatocellular carcinoma

The anti-programmed death-ligand 1 (PD-L1) antibody is a standard therapy for advanced hepatocellular carcinoma (HCC). Tumor expression of PD-L1 can be induced upon stimulus. Because cyclin-dependent kinase 9 (CDK9) inhibition reduces the expression of inducible proteins, we explored the influence of CDK9 inhibition on PD-L1 expression in HCC cells. We found that PD-L1 expression was low in HCC cells; however, IFN-γ treatment increased this expression. CDK9 inhibitors AZD4573 and atuveciclib reduced the IFN-γ induced PD-L1 expression in a dose-dependent manner. CDK9 knockdown yielded similar results, but CDK9 overexpression reversed the influence of the CDK9 inhibitors. In the orthotopic mouse model, mice treated with a CDK9 inhibitor and an anti-PD-L1 antibody had significantly smaller tumors and exhibited longer survival than mice treated with either agent. In conclusion, CDK9 inhibition could reduce the expression of PD-L1 in HCC cells. Using both CDK9 inhibitors and anti-PD-L1 antibodies is more effective than using either agent alone.

PH/glutathione-responsive theranostic nanoprobes for chemoimmunotherapy and magnetic resonance imaging of ovarian cancer cells

The integration of immunotherapy and standard chemotherapy holds great promise for enhanced anticancer effects. In this study, we prepared a pH- and glutathione (GSH)-sensitive manganese-doped mesoporous silicon (MMSNs) based drug delivery system by integrating paclitaxel (PTX) and anti-programmed cell death-ligand 1 antibody (aPD-L1), and encapsulating with polydopamine (PDA) for chemoimmunosynergic treatment of ovarian cancer cells. The nanosystem was degraded in response to the tumor weakly acidic and reductive microenvironment. The Mn2+ produced by degradation can be used as a contrast agent for magnetic resonance (MR) imaging to provide visual exposure to tumor tissue. The released PTX can not only kill tumor cells directly, but also induce immunogenic death (ICD) of tumor cells, which can play a synergistic therapeutic effect with aPD-L1. Therefore, our study is expected to provide a promising strategy for improving the efficacy of cancer immunotherapy and the detection rate of cancer.

A novel oral TLR7 agonist orchestrates immune response and synergizes with PD-L1 blockade via type I IFN pathway in lung cancer

Despite the groundbreaking impact of immune checkpoint blockade (ICB), response rates in non-small cell lung cancer remain modest, particularly in immune-excluded or immune-desert microenvironments. Toll-like receptor 7 (TLR7) emerges as a latent target bridging innate and adaptive immunity, offering a promising avenue for combination therapies to augment ICB efficacy. Here, we explored the anti-tumor activity of the novel oral TLR7 agonist TQ-A3334 and its potential to enhance anti-programmed death ligand 1 (PD-L1) therapy through a combination strategy in a syngeneic murine lung cancer model. Oral administration of TQ-A3334 significantly alleviated tumor burden in C57BL/6J mice, modulated by type I interferon (IFN), and exhibited low toxicity. This therapy elicited activation of both innate and adaptive immune cells in tumor tissue, particularly increasing the abundance of CD8+ TILs through type I IFN pathway and subsequent CXCL10 expression. In vitro examinations validated that IFN-α-stimulated tumor cells exhibited increased secretion of CXCL10, conducive to the promoted trafficking of CD8+ T cells. Furthermore, combining TQ-A3334 with anti-PD-L1 treatment exceeded tumor control, with a further increase in CD8+ TIL frequency compared to monotherapy. These findings suggest that TQ-A3334 can mobilize innate immunity and promote T cell recruitment into the tumor microenvironment; a combination of TQ-A3334 and anti-PD-L1 antibodies can intensify the sensitivity of tumors to anti-PD-L1 therapy, which demonstrates significant potential for treating poorly immune-infiltrated lung cancer.

Antibody nanoparticle conjugate-based targeted immunotherapy for non-small cell lung cancer.

The use of immune checkpoint inhibitors, which activate T cells, is a paradigm shift in the treatment of non-small cell lung cancer. However, the overall response remains low. To address this limitation, here we describe a novel platform, termed antibody-conjugated drug-loaded nanotherapeutics (ADN), which combines immunotherapy and molecularly targeted therapy. An ADN was designed with an anti-CD47 and anti-programmed death ligand 1 (PDL1) antibody pair on the surface of the nanoparticle and a molecularly targeted inhibitor of the PI3K (phosphatidylinositol 3-kinase)/AKT/mTOR (mammalian target of rapamycin) pathway, PI103, entrapped in the nanoparticle. The anti-CD47-PDL1-ADN exhibited greater antitumor efficacy than current treatment options with a PDL1 inhibitor in vivo in an aggressive lung cancer immunocompetent mouse model. Dual antibody-drug-loaded nanotherapeutics can emerge as an attractive platform to improve outcomes with cancer immunotherapy.

Necroptosis-Mediated Synergistic Photodynamic and Glutamine-Metabolic Therapy Enabled by a Biomimetic Targeting Nanosystem for Cholangiocarcinoma.

Targeted delivery of glutamine metabolism inhibitors holds promise for cholangiocarcinoma therapy, yet effective delivery vehicles remain a challenge. This study reports the development of a biomimetic nanosystem, termed R-CM@MSN@BC, integrating mesoporous organosilicon nanoparticles with reactive oxygen species-responsive diselenide bonds for controlled release of the glutamine metabolism inhibitor bis-2-(5-phenylacetamido-1,3,4-thiadiazol-2-yl) ethyl sulfide (BPTES) and the photosensitizer Ce6. Erythrocyte membrane coating, engineered with Arg-Gly-Asp (RGD) peptides, not only enhanced biocompatibility but also improved tumor targeting and tissue penetration. Upon laser irradiation, R-CM@MSN@BC executed both photodynamic and glutamine-metabolic therapies, inducing necroptosis in tumor cells and triggering significant immunogenic cell death. Time-of-flight mass cytometry analysis revealed that R-CM@MSN@BC can remodel the immunosuppressive tumor microenvironment by polarizing M1-type macrophages, reducing infiltration of M2-type and CX3CR1+ macrophages, and decreasing T cell exhaustion, thereby increasing the effectiveness of anti-programmed cell death ligand 1 immunotherapy. This strategy proposed in this study presents a viable and promising approach for the treatment of cholangiocarcinoma.

MB2033, an anti-PD-L1 × IL-2 variant fusion protein, demonstrates robust anti-tumor efficacy with minimal peripheral toxicity

Interleukin-2 (IL-2), a cytokine with pleiotropic immune effects, was the first approved cancer immunotherapy agent. However, IL-2 is associated with systemic toxicity due to binding with its ligand IL-2Rα, such as vascular leakage syndrome, limiting its clinical applications. Despite efforts to extend the half-life of IL-2 and abolish IL-2Rα interactions, the risk of toxicity remains unresolved. In this study, we developed the bispecific fusion protein MB2033, comprising a novel IL-2 variant (IL-2v) connected to anti-programmed death ligand 1 (PD-L1) via a silenced Fc domain. The IL-2v of MB2033 exhibits attenuated affinity for IL-2Rβγ without binding to IL-2Rα. The binding affinity of MB2033 for PD-L1 is greater than that for IL-2Rβγ, indicating its preferential targeting of PD-L1+ tumor cells to induce tumor-specific immune activation. Accordingly, MB2033 exhibited significantly reduced regulatory T cell activation, while inducing comparable CD8+ T cell activation to recombinant human IL-2 (rhIL-2). MB2033 induced lower immune cell expansion and reduced cytokine levels compared with rhIL-2 in human peripheral blood mononuclear cells, indicating a decreased risk of peripheral toxicity. MB2033 exhibited superior anti-tumor efficacy, including tumor growth inhibition and complete responses, compared with avelumab monotherapy in an MC38 syngeneic mouse model. In normal mice, MB2033 was safer than non-α IL-2v and tolerable up to 30 mg/kg. These preclinical results provide evidence of the dual advantages of MB2033 with an enhanced safety and potent clinical efficacy for cancer treatment.

Power-Doppler-based NH002 microbubble sonoporation with chemotherapy relieves hypoxia and enhances the efficacy of chemotherapy and immunotherapy for pancreatic tumors

Pancreatic ductal adenocarcinoma (PDAC) poses challenges due to late-stage diagnosis and limited treatment response, often attributed to the hypoxic tumor microenvironment (TME). Sonoporation, combining ultrasound and microbubbles, holds promise for enhancing therapy. However, additional preclinical research utilizing commercially available ultrasound equipment for PDAC treatment while delving into the TME's intricacies is necessary. This study investigated the potential of using a clinically available ultrasound system and phase 2-proven microbubbles to relieve tumor hypoxia and enhance the efficacy of chemotherapy and immunotherapy in a murine PDAC model. This approach enables early PDAC detection and blood-flow-sensitive Power-Doppler sonoporation in combination with chemotherapy. It significantly extended treated mice's median survival compared to chemotherapy alone. Mechanistically, this combination therapy enhanced tumor perfusion and substantially reduced tumor hypoxia (77% and 67%, 1- and 3-days post-treatment). Additionally, cluster of differentiation 8 (CD8) T-cell infiltration increased four-fold afterward. The combined treatment demonstrated a strengthening of the anti-programmed death-ligand 1(αPDL1) therapy against PDAC. Our study illustrates the feasibility of using a clinically available ultrasound system with NH-002 microbubbles for early tumor detection, alleviating hypoxic TME, and improving chemotherapy and immunotherapy. It suggests the development of an adjuvant theragnostic protocol incorporating Power-Doppler sonoporation for pancreatic tumor treatment.

A phase II study of anlotinib and an anti-PDL1 antibody in patients with alveolar soft part sarcoma: Results of expansion cohorts.

11515 Background: The combination of the anti-angiogenesis tyrosine kinase inhibitor (TKI), anlotinib, with the anti-programmed death-ligand 1 (PDL1) antibody (TQB2450) demonstrated commendable antitumor efficacy in a phase II clinical trial for pan-sarcoma patients, particularly within the alveolar soft part sarcoma (ASPS) cohorts (Liu et al., 2022, PMID: 35675031). An expansion of the ASPS cohort has been underway since 2019. Herein, we present the observed efficacy within this ASPS-specific expansion cohort. Methods: ASPS patients naïve to TKIs or immunotherapy received TQB2450 (1200mg) intravenously on day 1, in combination with oral administration of anlotinib (12mg) from day 1 to 14, repeated every 3 weeks. The primary endpoint was best objective response rate (ORR, per RECIST v1.1). Secondary endpoints comprised median progression free survival (PFS), median overall survival (OS), duration of response (DOR), and adverse events (AEs). Formalin-fixed paraffin-embedded (FFPE) slides were taken for immunohistochemistry and examined for lymphocyte marker expression. Results: Twenty-nine patients were enrolled in the phase II trial. The median age was 29 years (range: 19-46), with female 48.3%. A subset of patients (20.7%) had undergone prior lines of chemotherapy. Twenty-eight patients were evaluable for efficacy (one withdrew). The ORR for evaluable patients reached 79.3%, characterized by 3 complete responses and 20 partial responses. The median PFS (months) was not reached (95%CI: 20.7, not-reached). The median DOR (months) for responders was not reached (95%CI: 18.0, not-reached). No mortalities occurred during the follow-up. Treatment demonstrated favorable tolerability, with predominant grade 1 and 2 AEs. Thirteen patients (44.83%) experienced grade ≥3 AEs, principally hypertriglyceridemia (13.79%), lipase elevation (6.90%), amylase elevation (3.45%), and hypertension (3.45%). A detailed analysis of the tumor microenvironment in 7 patients, including 3 good responders and 4 poor responders, revealed a significant discrepancy in the presence of tertiary lymphoid structures (TLS) between the two groups (refer to Table). Conclusions: The combination of anlotinib and TQB2450 exhibits promising efficacy in ASPS patients, markedly enhancing ORR and extending PFS with favorable tolerability. Notably, TLS emerges as a potential predictive indicator of immunotherapeutic efficacy in ASPS. Clinical trial information: CTR20190938 . [Table: see text]

BGB-A317-212: A multicenter, open-label, phase II study to evaluate the efficacy and safety of tislelizumab in combination with lenvatinib in patients with selected solid tumors.

2610 Background: Tislelizumab, an anti-programmed cell death protein 1 (PD-1) monoclonal antibody, has demonstrated promising efficacy in several advanced solid tumors. However, some patients (pts) do not respond or develop resistance to tislelizumab monotherapy. Lenvatinib, a receptor tyrosine kinase inhibitor targeting VEGFR 1-3, FGFR 1-4, PDGFR alpha, KIT, and RET, has shown a potential synergistic effect with anti-PD-1 therapy. Here, we report the primary results of a phase II study evaluating the combination of tislelizumab plus lenvatinib in pts with solid tumors (NCT05014828). Methods: Pts with histologically/cytologically confirmed selected solid tumors, naïve to lenvatinib and anti-programmed death-ligand 1 (PD-L1)/PD-1 therapies were enrolled. Part 1 (safety run-in) determined the recommended phase II dose (RP2D) of lenvatinib in combination with tislelizumab 400 mg IV every 6 weeks. In Part 2 (expansion), pts received lenvatinib at the RP2D from Part 1 (20 mg orally/day) plus tislelizumab per the Part 1 regimen until disease progression, withdrawal, or death. The primary endpoints were safety and RP2D determination (Part 1) and overall response rate (ORR; Part 2). Results: At data cutoff (Oct 20, 2023; median follow-up 12.1 months [mo; renal cell carcinoma, RCC]; 10.8 mo [head and neck squamous cell carcinoma, HNSCC]; 14.8 mo [gastric cancer, GC], and 22.0 mo [non-small cell lung cancer, NSCLC]), 58 pts were treated in Part 2 (RCC, n=23; HNSCC, n=27; GC, n=3; NSCLC, n=5), 6 of whom were also included in Part 1. The ORR was 66.7% in pts with RCC, 33.3% (HNSCC), 33.3% (GC), and 20.0% (NSCLC). Median duration of response (mDoR) was 18.5 mo and 9.6 mo in pts with NSCLC and HNSCC, respectively; not estimable (NE) for RCC and GC (Table). No new safety signals were identified; grade ≥3 treatment-related adverse events were reported in 78.3%, 59.3%, 33.3% and 60.0%, of pts with RCC, HNSCC, GC, and NSCLC, respectively (Table). Conclusions: Tislelizumab plus lenvatinib had a manageable safety profile and showed preliminary antitumor activity in pts with selected tumor types. Longer follow-up is needed to further investigate the potential of this combination to benefit pts with advanced solid tumors. Clinical trial information: NCT05014828 .[Table: see text]

Efficacy and safety of arterial FOLFOX chemotherapy plus anti-PD-(L)1 immunotherapy as first-line treatment for unresectable intrahepatic cholangiocarcinoma: A propensity score matched analysis.

e16189 Background: This study aimed to evaluate the efficacy and safety of hepatic arterial infusion chemotherapy (HAIC) plus anti-programmed death (ligand)-1 [PD-(L)1] immunotherapy compared to systemic chemotherapy (SCT) plus anti-PD-(L)1 immunotherapy as first-line treatment for patients with unresectable intrahepatic cholangiocarcinoma (uICC). Methods: In this retrospective study, unresectable treatment-naive ICC patients who were treated with HAIC plus anti-PD-(L)1 immunotherapy [HAIC+αPD-(L)1] or SCT plus anti-PD-(L)1 immunotherapy [SCT+αPD-(L)1] were included. The clinical characteristics, therapeutic outcomes and adverse events (AEs) of patients between the two groups were compared. The propensity score matching (PSM) was performed to minimize biases between groups. Results: From January 2019 to January 2023, a total of 182 patients were enrolled, including 147 patients in HAIC+αPD-(L)1 group and 35 patients in SCT+αPD-(L)1 group. After PSM, 61 and 26 patients were included in the HAIC+αPD-(L)1 and SCT+αPD-(L)1 groups, respectively. The HAIC+αPD-(L)1 group showed longer median overall survival (OS) and progression free survival (PFS) than the SCT+αPD-(L)1 group (OS: 14.5 vs 10.5 months, P = 0.019; PFS: 6.4 vs 10.1 months, P = 0.020). The disease control rate of HAIC+αPD-(L)1 group were higher than those of SCT+αPD-(L)1 group (91.8% vs 69.2%, P = 0.007). The overall incidence of adverse events (AEs) was comparable between the two groups, but the HAIC+αPD-(L)1 group showed a lower incidence of grade 3~4 AEs related to anemia, weight loss and fatigue. Conclusions: HAIC plus anti-PD-(L)1 immunotherapy had acceptable toxic effects and might improve outcomes compared to SCT plus anti-PD-(L)1 immunotherapy as first-line treatment for patients with uICC.

Adverse Event Profile of Atezolizumab, Bevacizumab, Carboplatin, and Paclitaxel Combination Therapy Based on JADER.

There have been advances in the development of immune checkpoint inhibitors for monotherapy and combination therapy with other anticancer agents in recent years. The combination of bevacizumab, carboplatin, and paclitaxel with atezolizumab, an anti-programmed death ligand 1 antibody (ABCP therapy), has been reported to be effective for treating non-small cell lung cancer. However, reports on its adverse events are limited. In this study, a survey and disproportionality analysis based on the Japanese Adverse Drug Event Report (JADER) database was conducted to elucidate the adverse event profile of ABCP therapy. The reporting odds ratio (ROR) and information component were used as indicators for the disproportionality analysis. The ROR was also used to assess the changes in the reporting intensity with combination therapy, and the mutual exclusivity of the 95% confidence interval between the compared groups was considered. The reported adverse events of ABCP therapy mirrored those of the individual drugs that constituted it. ABCP therapy enhanced the reporting intensity of adverse events related to leukocytes and the skin, while decreased those related to interstitial lung disease and hepatic function abnormality as immune-related adverse events caused by atezolizumab, and gastrointestinal perforation caused by bevacizumab. Our analysis of data from the JADER database has revealed the adverse event profile of ABCP therapy. Our findings emphasize the importance of effectively managing febrile neutropenia and skin-related adverse events in ABCP therapy.

Treatment rationale and protocol design: an investigator-initiated phase II study of combination treatment of nivolumab and TM5614, a PAI-1 inhibitor for previously treated patients with non-small cell lung cancer.

There is no established standard 3rd line treatment for patients with advanced non-small cell lung cancer (NSCLC). Although cytotoxic chemotherapeutic agents that are not used as 1st or 2nd line treatment are administrated as 3rd line treatment, their anti-tumor efficacy is insufficient. Anti-programmed death ligand-1 (PD-L1)/programmed death-1 (PD1) treatment is more effective and less toxic than chemotherapy in anti-PD-L1/PD-1 treatment-naïve patients with NSCLC. Therefore, anti-PD-L1/PD-1 therapy is considered an appropriate 3rd line treatment. However, the anti-tumor efficacy is limited in patients previously treated with anti-PD-L1/PD-1 antibody. Today, new drugs are needed to increase the efficacy of anti-PD-L1/PD-1 antibodies. This open-label, single-arm, investigator-initiated phase II study is designed to evaluate combination treatment of nivolumab and TM5614, a plasminogen activator inhibitor (PAI-1) inhibitor as 3rd or more line treatment in NSCLC patients who underwent standard treatment. The primary endpoint is the objective response rate and the secondary endpoints are progression-free survival (PFS), overall survival (OS), duration of response (DOR) and safety. Recruitment began in September 2023 and is expected to continue for approximately three years. Currently, there is no standard 3rd line treatment for advanced NSCLC, and we hope that the findings of this study will facilitate more effective treatments in this setting. Ethics and dissemination: the study protocol conformed to the ethical principles outlined in the Declaration of Helsinki. All patients will provide written informed consent prior to enrollment. Results will be published in a peer-reviewed publication. This study is registered to Japan Registry of Clinical Trials with number: jRCT2061230039 (19/July/2023).

RPN1: a pan-cancer biomarker and disulfidptosis regulator.

Elevated expression of SLC7A11, in conjunction with glucose deprivation, has revealed disulfidptosis as an emerging cell death modality. However, the prevalence of disulfidptosis across tumor cell lines, irrespective of SLC7A11 levels, remains uncertain. Additionally, deletion of the ribophorin I (RPN1) gene imparts resistance to disulfidptosis, yet the precise mechanism linking RPN1 to disulfidptosis remains elusive. The aim of this study is to determine the mechanism of RPN1-induced disulfidptosis and to determine the possibility of RPN1 as a pan-cancer marker. We hypothesized the widespread occurrence of disulfidptosis in various tumor cells, and proposed that RPN1-mediated disulfidptosis may be executed through cell skeleton breakdown. Experimental validation was conducted via flow cytometry, immunofluorescence, and western blot techniques. Furthermore, given RPN1's status as an emerging cell death marker, we utilized bioinformatics to analyze its expression in tumor tissues, clinical relevance, mechanisms within the tumor microenvironment, and potential for immunotherapy. Conducting experiments on breast cancer (MDA-MB-231) and lung cancer (A549) cell lines under glucose-starved conditions, we found that RPN1 primarily induces cell skeleton breakdown to facilitate disulfidptosis. RPN1 demonstrated robust messenger RNA (mRNA) expression across 16 solid tumors, validated by data from 12 tumor types in the Gene Expression Omnibus (GEO). Across 12 cancer types, RPN1 exhibited significant diagnostic potential, particularly excelling in accuracy for glioblastoma (GBM). Elevated RPN1 expression in tumor tissues was found to correlate with improved overall survival (OS) in certain cancers [diffuse large B-cell lymphoma (DLBC) and thymoma (THYM)] but poorer prognosis in others [adrenocortical carcinoma (ACC), kidney chromophobe (KICH), brain lower grade glioma (LGG), liver hepatocellular carcinoma (LIHC), and pancreatic adenocarcinoma (PAAD)]. RPN1 is enriched in immune-related pathways and correlates with immune scores in tumor tissues. In urothelial carcinoma (UCC), RPN1 demonstrates potential in predicting the efficacy of anti-programmed cell death ligand 1 (PD-L1) immune therapy. This study underscores RPN1's role in facilitating disulfidptosis, its broad relevance as a pan-cancer biomarker, and its association with the efficacy of anti-PD-L1 immune therapy.

YTHDF3 phase separation regulates HSPA13-dependent clear cell renal cell carcinoma development and immune evasion.

Insufficient understanding about the immune evasion mechanism leads to the inability in predicting current immunotherapy effects in clear cell renal cell carcinoma (ccRCC) and sensitizing ccRCC to immunotherapy. RNA binding proteins (RBPs) can promote tumor progression and immune evasion. However, research on RBPs, particularly m6A reader YTHDF3, in ccRCC development and immune evasion is limited. In this study, we found that YTHDF3 level was downregulated in ccRCC and was an independent prognostic biomarker for ccRCC. Decreased YTHDF3 expression was correlated with the malignancy, immune evasion, and poor response to anti-programmed death ligand 1 (PD-L1)/CTLA-4 in ccRCC. YTHDF3 overexpression restrained ccRCC cell malignancy, PD-L1 expression, CD8+ T cell infiltration and activities invivo, indicating its inhibitory role in ccRCC development and immune evasion. Mechanistically, YTHDF3 WT was found to have phase separation characteristics and suppress ccRCC malignancy and immune evasion. Whereas YTHDF3 mutant, which disrupted phase separation, abolished its function. YTHDF3 enhanced the degradation of its target mRNA HSPA13 by phase separation and recruiting DDX6, resulting in the downregulation of the downstream immune checkpoint PD-L1. HSPA13 overexpression restored ccRCC malignancy and immune evasion suppressed by YTHDF3 overexpression. In all, our results identify a new model of YTHDF3 in regulating ccRCC progression and immune evasion through phase separation.

Immune checkpoint inhibitors: breakthroughs in cancer treatment.

Over the past two decades, immunotherapies have increasingly been considered as first-line treatments for most cancers. One such treatment is immune checkpoint blockade (ICB), which has demonstrated promising results against various solid tumors in clinical trials. Monoclonal antibodies (mAbs) are currently available as immune checkpoint inhibitors (ICIs). These ICIs target specific immune checkpoints, including cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death protein 1 (PD-1). Clinical trial results strongly support the feasibility of this immunotherapeutic approach. However, a substantial proportion of patients with cancer develop resistance or tolerance to treatment, owing to tumor immune evasion mechanisms that counteract the host immune response. Consequently, substantial research focus has been aimed at identifying additional ICIs or synergistic inhibitory receptors to enhance the effectiveness of anti-PD-1, anti-programmed cell death ligand 1 (anti-PD-L1), and anti-CTLA-4 treatments. Recently, several immune checkpoint molecular targets have been identified, such as T cell immunoreceptor with Ig and ITIM domains (TIGIT), mucin domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), V-domain immunoglobulin suppressor of T cell activation (VISTA), B and T lymphocyte attenuator (BTLA), and signal-regulatory protein α (SIRPα). Functional mAbs targeting these molecules are under development. CTLA-4, PD-1/PD-L1, and other recently discovered immune checkpoint proteins with distinct structures are at the forefront of research. This review discusses these structures, as well as clinical progress in mAbs targeting these immune checkpoint molecules and their potential applications.

Immune checkpoint inhibitors for POLE or POLD1 proofreading-deficient metastatic colorectal cancer

POLE and POLD1 proofreading deficiency (POLE/D1pd) define a rare subtype of ultramutated metastatic colorectal cancer (mCRC; over 100 mut/Mb). Disease-specific data about the activity and efficacy of immune checkpoint inhibitors (ICIs) in POLE/D1pd mCRC are lacking and it is unknown whether outcomes may be different from mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) mCRCs treated with ICIs. In this global study, we collected 27 patients with mCRC harboring POLE/D1 mutations leading to proofreading deficiency and treated with anti-programmed cell death-ligand 1 alone+/- anti-cytotoxic T-lymphocyte antigen-4 agents. We collected clinicopathological and genomic characteristics, response, and survival outcomes after ICIs of POLE/D1pd mCRC and compared them with a cohort of 610 dMMR/MSI-H mCRC patients treated with ICIs. Further genomic analyses were carried out in an independent cohort of 7241 CRCs to define POLE and POLD1pd molecular profiles and mutational signatures. POLE/D1pd was associated with younger age, male sex, fewer RAS/BRAF driver mutations, and predominance of right-sided colon cancers. Patients with POLE/D1pd mCRC showed a significantly higher overall response rate (ORR) compared to dMMR/MSI-H mCRC (89% versus 54%; P= 0.01). After a median follow-up of 24.9 months (interquartile range: 11.3-43.0 months), patients with POLE/D1pd showed a significantly superior progression-free survival (PFS) compared to dMMR/MSI-H mCRC [hazard ratio (HR)= 0.24, 95% confidence interval (CI) 0.08-0.74, P= 0.01] and superior overall survival (OS) (HR= 0.38, 95% CI 0.12-1.18, P= 0.09). In multivariable analyses including the type of DNA repair defect, POLE/D1pd was associated with significantly improved PFS (HR= 0.17, 95% CI 0.04-0.69, P=0.013) and OS (HR= 0.24, 95% CI 0.06-0.98, P= 0.047). Molecular profiling showed that POLE/D1pd tumors have higher tumor mutational burden (TMB). Responses were observed in both subtypes and were associated with the intensity of POLE/D1pd signature. Patients with POLE/D1pd mCRC showed more favorable outcomes compared to dMMR/MSI-H mCRC to treatment with ICIs in terms of tumor response and survival.

Optimization of immune checkpoint inhibitor treatment planning for relapsed or refractory extranodal NK/T cell lymphoma.

Pembrolizumab (anti-programmed cell death-ligand 1 inhibitor) is a promising salvage therapeutic option for relapsed/refractory extranodal NK/T-cell lymphoma (R/R ENKTL). However, the appropriate duration of pembrolizumab use in R/R ENKTL patients and the optimal timing for administering pembrolizumab remain undetermined. We collected and analyzed clinical information on R/R ENKTL 58 patients who received pembrolizumab to evaluate the optimal treatment durations and clinical information for considering treatment interruption. Treatment outcomes were assessed by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) and Epstein Barr virus DNA (EBV DNA) every 3months. Nineteen (32.8%) patients had been treated with more than three chemotherapies before pembrolizumab administration. The best response rate towards the first try of pembrolizumab was 38.9% (31.5% complete response rate (CR), 7.4% partial response (PR)). During the 41.8-month median follow-up duration, the median progression-free survival (PFS) was 3.1months, and the median overall survival (OS) was 7.1months. The failure group, which was characterized by Deaville score (DS) 3-4 and circulating EBV detection, or DS 5 with/without EBV detection, had the worst PFS (p < 0.001) and OS (p < 0.001), followed by the high (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected) and low-risk groups (DS 1-2 and EBV not detected). Among the 21 patients who achieved the best response at the first pembolizumab try, the patients who received planned 24 cycles presented better PFS than those who received incomplete cycles (57.6 months vs 20.9 months, P-value = 0.012). Among 13 patients who received avelumab or pembrolizumab in advance, a few who responded to the second trial of pembrolizumab administration had over one year of chemotherapy vacation. Determining the discontinuation or continuation of pembrolizumab would be considered in selected cases assessed by PET-CT and EBV monitoring. Disruption of pembrolizumab treatment may be advisable for the low-risk group(DS 1-2 and EBV not detected), whereas continuation could be warranted for the high-risk group (DS 1-2 and EBV detection, or DS 3-4 and EBV not detected). Moreover, it might be critical to maintain over 24 cycles to improve the survival outcome of R/R ENKTL.

Natural history of SCLC patients treated in third-line and beyond: A retrospective real world study

ObjectivesTo describe treatment patterns and estimate outcomes among real-world small cell lung cancer (SCLC) patients in the US who received three or more lines of therapy. Materials and methodsWe conducted a retrospective analysis of adult patients with SCLC who received a front-line platinum-based regimen and two additional lines of therapy (ie., a cohort of at least three lines of therapy). De-identified patients were selected from a United States Flatiron Health oncology database of electronic health records. Treatment patterns were captured by line of therapy. Outcomes evaluated by line of therapy included real-world overall survival (rwOS), real-world progression free survival (rwPFS), real-world response rate (rwRR) and real-world duration of response (rwDOR). ResultsThe analysis included 326 3L SCLC patients, of which 103 (32 %) received 4L treatment, and 38 % (39/103) of 4L treated received 5L of therapy. Among the 3L cohort, the average age was 67 years, 49 % were male, and nearly all had a history of smoking (96 %). In the 3L setting, the median rwOS was 5.3 months (95 % Confidence Interval (CI): 4.5, 6.0), median rwPFS was 2.5 months (95 % CI: 2.1, 2.7), rwRR was 19.3 % (95 % CI: 15.2, 24.0) and median DOR was 3.4 months (95 % CI: 2.8, 4.4). No differences were seen in outcomes between the overall cohort and a subgroup of patients treated with front-line platinum-based regimen with an anti-programmed cell death ligand 1 (PD-L1) agent (atezolizumab or durvalumab), in each respective line of therapy. ConclusionResults from this large, real-world study of US patients with SCLC in the 3L setting and beyond highlight the poor treatment outcomes in advanced SCLC patients with existing therapies and underscore the dire need for new therapies for SCLC patients.

Evaluating the Therapeutic Potential of Durvalumab in Adults with Locally Advanced or Metastatic Biliary Tract Cancer: Evidence to Date.

Advanced biliary tract cancers (BTCs) have historically been managed with chemotherapy but, in recent years, this treatment paradigm has begun to shift with the introduction of immune checkpoint inhibitors in addition to standard of care chemotherapy. The tumor microenvironment of BTC may be enriched with regulatory T lymphocytes and immune checkpoint expression in some patients. Durvalumab, an anti-programmed death ligand-1 (PD-L1) antibody, in combination with gemcitabine and cisplatin, has now received United States Food and Drug Administration approval for treatment of advanced BTC. Regulatory approval was based on the Phase III, randomized TOPAZ-1 trial that demonstrated survival benefit with addition of durvalumab to gemcitabine plus cisplatin compared to chemotherapy alone. The combination of chemotherapy and immunotherapy was well tolerated, and a subset of patients were able to achieve a durable response, with a 2-year overall survival rate of 23.6%. However, limitations remain in identifying which patients are most likely to benefit from immune checkpoint inhibition. Future study should aim to identify biomarkers predictive of substantial benefit, as well as the role of immune checkpoint inhibition in combination with targeted therapies and radiotherapy in the management of advanced BTC.