Improvement of the anticancer efficacy of PD-1/PD-L1 blockade via combination therapy and PD-L1 regulation

Nanomotors activating both cGAS-STING pathway and immune checkpoint blockade for tumor therapy and bioimaging

Cellular innate immune response is closely related to cGAS-STING pathway and PD-1/PD-L1 immune checkpoint blockade. The lack of tissue penetration of STING agonists and nanomedicines in conventional approaches reduces their immunotherapeutic efficacy. At the same time, because the cGAS-STING signaling pathway is silent in many breast cancer cells, it cannot play its role. To address these challenges, here, we developed a silica nanomotor based on bubble propulsion. Its hollow structure was packed with the photosensitizer Ce6 molecule. Under 808 nm laser irradiation, Ce6 produced 1O2, which lead to intracellular DNA damage and further activated the cGAS-STING pathway, stimulating the maturation of DC cells, and enhancing the tumor infiltration of CD8+ T cells. The nanomotor had an asymmetrical structure. One side of the nanomotor was modified with Pt nanoparticle. This asymmetric modification can catalyze H2O2 in the environment, producing an asymmetric concentration of O2, which realized the bubble driving nanomotor movement and enhances penetration into breast cancer cells of nanomotor. The other side of the nanomotor was modified the LXL-1 aptamer, triphenylphosphine and peptide CLP002. Peptide CLP002 specifically bound residues of PD-L1 interaction with PD-1, blocked the mutual binding between PD-1 and PD-L1, and further improved the immune response ability of tumor infiltrating T cells. In this study, we developed a multi-pronged immunotherapy strategy of intelligent target finding, breaking through the physiological barrier through kinetic energy, accurately intervening the target and bioimaging, providing a new idea for breast cancer cells targeted therapy.

Frontiers in pancreatic cancer on biomarkers, microenvironment, and immunotherapy

Pancreatic cancer remains one of the most challenging malignancies to treat due to its late-stage diagnosis, aggressive progression, and high resistance to existing therapies. This review examines the latest advancements in early detection, and therapeutic strategies, with a focus on emerging biomarkers, tumor microenvironment (TME) modulation, and the integration of artificial intelligence (AI) in data analysis. We highlight promising biomarkers, including microRNAs (miRNAs) and circulating tumor DNA (ctDNA), that offer enhanced sensitivity and specificity for early-stage diagnosis when combined with multi-omics panels. A detailed analysis of the TME reveals how components such as cancer-associated fibroblasts (CAFs), immune cells, and the extracellular matrix (ECM) contribute to therapy resistance by creating immunosuppressive barriers. We also discuss therapeutic interventions that target these TME components, aiming to improve drug delivery and overcome immune evasion. Furthermore, AI-driven analyses are explored for their potential to interpret complex multi-omics data, enabling personalized treatment strategies and real-time monitoring of treatment response. We conclude by identifying key areas for future research, including the clinical validation of biomarkers, regulatory frameworks for AI applications, and equitable access to innovative therapies. This comprehensive approach underscores the need for integrated, personalized strategies to improve outcomes in pancreatic cancer.

An ultra-long-acting L-asparaginase synergizes with an immune checkpoint inhibitor in starvation-immunotherapy of metastatic solid tumors

Metastasis stands as the primary contributor to mortality associated with tumors. Chemotherapy and immunotherapy are frequently utilized in the management of metastatic solid tumors. Nevertheless, these therapeutic modalities are linked to serious adverse effects and limited effectiveness in preventing metastasis. Here, we report a novel therapeutic strategy named starvation-immunotherapy, wherein an immune checkpoint inhibitor is combined with an ultra-long-acting L-asparaginase that is a fusion protein comprising L-asparaginase (ASNase) and an elastin-like polypeptide (ELP), termed ASNase-ELP. ASNase-ELP's thermosensitivity enables it to generate an in-situ depot following an intratumoral injection, yielding increased dose tolerance, improved pharmacokinetics, sustained release, optimized biodistribution, and augmented tumor retention compared to free ASNase. As a result, in murine models of oral cancer, melanoma, and cervical cancer, the antitumor efficacy of ASNase-ELP by selectively and sustainably depleting L-asparagine essential for tumor cell survival was substantially superior to that of ASNase or Cisplatin, a first-line anti-solid tumor medicine, without any observable adverse effects. Furthermore, the combination of ASNase-ELP and an immune checkpoint inhibitor was more effective than either therapy alone in impeding melanoma metastasis. Overall, the synergistic strategy of starvation-immunotherapy holds excellent promise in reshaping the therapeutic landscape of refractory metastatic tumors and offering a new alternative for next-generation oncology treatments.

A comprehensive review of immune checkpoint inhibitors for cancer treatment

Immunology-based therapies are emerging as an effective cancer treatment, using the body's immune system to target tumors. Immune checkpoints, which regulate immune responses to prevent tissue damage and autoimmunity, are often exploited by cancer cells to avoid destruction. The discovery of checkpoint proteins like PD-1/PD-L1 and CTLA-4 was pivotal in developing cancer immunotherapy. Immune checkpoint inhibitors (ICIs) have shown great success, with FDA-approved drugs like PD-1 inhibitors (Nivolumab, Pembrolizumab, Cemiplimab), PD-L1 inhibitors (Atezolizumab, Durvalumab, Avelumab), and CTLA-4 inhibitors (Ipilimumab, Tremelimumab), alongside LAG-3 inhibitor Relatlimab. Research continues on new checkpoints like TIM-3, VISTA, B7-H3, BTLA, and TIGIT. Biomarkers like PDL-1 expression, tumor mutation burden, interferon-γ presence, microbiome composition, and extracellular matrix characteristics play a crucial role in predicting responses to immunotherapy with checkpoint inhibitors. Despite their effectiveness, not all patients experience the same level of benefit, and organ-specific immune-related adverse events (irAEs) such as rash or itching, colitis, diarrhea, hyperthyroidism, and hypothyroidism may occur. Given the rapid advancements in this field and the variability in patient outcomes, there is an urgent need for a comprehensive review that consolidates the latest findings on immune checkpoint inhibitors, covering their clinical status, biomarkers, resistance mechanisms, strategies to overcome resistance, and associated adverse effects. This review aims to fill this gap by providing an analysis of the current clinical status of ICIs, emerging biomarkers, mechanisms of resistance, strategies to enhance therapeutic efficacy, and assessment of adverse effects. This review is crucial to furthering our understanding of ICIs and optimizing their application in cancer therapy.

Identification of a novel subtype of SPP1 + macrophages expressing SIRPα: implications for tumor immune evasion and treatment response prediction

BACKGROUND

SPP1 + macrophages are among the major phagocytic cells, yet promoting tumor immune evasion and predicting unfavorable prognosis, in various cancer types. Meanwhile, the predictive value of the abundance of SPP1 + macrophages in patients receiving immunotherapy remains debatable, indicating the potential existence of subtypes of SPP1 + macrophages with diverse biological functions.

METHODS

The single cell RNA sequencing data of myeloid cells integrated from several cancers including esophageal squamous cell carcinoma was analyzed for characterizing the function and cellular interactions of SPP1 + macrophages expressing SIRPα. Multiplexed immunohistochemistry was used to quantify the quantity and spatial distribution of SPP1 + macrophages expressing SIRPα. Kaplan-Meier method was used for survival analysis. In vitro and in vivo studies investigating the function of SPP1 + macrophages were performed.

RESULTS

SPP1 + macrophages possessed a high phagocytic signature and could engulf more tumor cells in vitro and in vivo. SIRPα expression could represent the phagocytic activity of SPP1 + macrophages and delineated subsets of SPP1 + macrophages with different functions. SPP1 + SIRPα + macrophages showed close spatial distance to tumor cells and positively correlated with PD1 + CD8 + T cells. A high abundance of SPP1 + SIRPα + macrophages at baseline corresponded to patients' response to PD-1/PD-L1 inhibitors.

CONCLUSION

A novel subtype of SPP1 + macrophages expressing SIRPα was identified and their abundance predicted patients' response to PD-1/PD-L1 inhibitors.

Anti-PD-L1 Antibody Fragment Linked to Tumor-Targeting Lipid Nanoparticle Can Eliminate Cancer and Its Metastasis via Photoimmunotherapy

Effective cancer therapy aims to treat primary tumors and metastatic and recurrent cancer. Immune checkpoint blockade-mediated immunotherapy has shown promising effects against tumors; however, its efficacy in metastatic or recurrent cancer is limited. Here, based on the advantages of nanomedicine, lipid nanoparticles (LNPs) that can target tumors are synthesized for photothermal therapy (PTT) and immunotherapy to treat primary and metastatic recurrent cancer. These LNPs, termed piLNPs, are encapsulated with indocyanine green and incorporated with the antigen (Ag)-binding fragment of the anti-PD-L1 antibody for targeting tumors and immunotherapy. Intravenously injected piLNPs in 4T1 breast tumor-bearing BALB/c mice effectively target the 4T1 tumor and are suitable for performing PTT using a near-infrared laser. Moreover, lung metastatic 4T1 tumor growth is completely prevented in mice previously cured of the 4T1 breast tumor by piLNP treatment and rechallenged with lung 4T1 metastatic cancer. Blockage of the second challenged metastatic 4T1 breast cancer by piLNP is due to the activation of Ag-specific T cells. Cytotoxic T lymphocytes from piLNP-cured mice selectively attack 4T1 breast cancer cells. Therefore, piLNP can be used as a multifunctional breast cancer treatment composition that can target tumors, treat primary tumors, and prevent metastasis and recurrence.

SpliceMutr Enables Pan-Cancer Analysis of Splicing-Derived Neoantigen Burden in Tumors

SIGNIFICANCE

SpliceMutr shows that splicing antigenicity changes in response to ICI therapies and that native modulation of the splicing machinery through mutations increases the contribution of splicing to the neoantigen load of some The Cancer Genome Atlas cancer subtypes. Future studies of the relationship between splicing antigenicity and immune checkpoint inhibitor response pan-cancer are essential to establish the interplay between antigen heterogeneity and immunotherapy regimen on patient response.

Elevated serum magnesium levels prompt favourable outcomes in cancer patients treated with immune checkpoint blockers

BACKGROUND

Magnesium deficiency influences the activation and cytotoxicity of immune cells. Nevertheless, whether serum magnesium levels influence the clinical outcomes of immune checkpoint blockers (ICBs) treatment still remains ambiguous. There is an urgent need for clinical research to elucidate the relationship between serum magnesium levels and the outcomes of ICB therapy. Such insights could offer new perspectives on immunotherapy for cancer.

METHODS

A multi-center retrospective study involving in pan-cancer patients treated with ICBs at three large cancer centers from August 2012 to May 2023 was conducted. The primary objective was to assess the correlation between serum magnesium levels and therapeutic response in patients receiving ICBs, and further evaluate the associations between serum magnesium levels and progression-free survival (PFS) and overall survival (OS).

RESULTS

A total of 1441 patients treated with ICBs, including 1042 with lung cancer, 270 with esophageal cancer, and 129 with Hodgkin lymphoma, were enrolled in this study. We found that patients with elevated serum magnesium levels exhibited a favourable response to ICBs treatment. The optimal cut-off point for serum magnesium level (0.79 mmol/L) was applied for stratifying patients into distinct groups. In the three tumor cohorts, patients in high magnesium level group (Mg2+ ≥ 0.79 mmol/L) had longer PFS and OS than those in low magnesium level group (Mg2+ < 0.79 mmol/L). Univariate and multivariate analyses confirmed that the serum Mg2+ level serves as an independent prognostic factor for cancer patients receiving ICBs therapy.

CONCLUSION

Our multi-center study demonstrated that among patients receiving ICBs therapy, those with elevated serum magnesium levels exhibit significantly better clinical outcomes than those with low serum magnesium levels. Further prospective validation studies are needed to confirm these findings.

The first-in-class bispecific antibody IBI318 (LY3434172) targeting PD-1 and PD-L1 in patients with advanced tumors: a phase Ia/Ib study

BACKGROUND

There is an unmet clinical need to enhance the response rate and safety of anti-PD-1/PD-L1-based cancer immunotherapy (IO). Herein, we presented the clinical study of IBI318 (LY3434172), a first-in-class bispecific antibody (bsAb) targeting PD-1 and PD-L1, in patients with advanced tumors.

METHODS

In this open-label, multicenter Phase Ia/Ib study of IBI318, the Phase Ia involved dose escalation and a safety dose expansion, while the Phase Ib focused on preliminary safety and efficacy evaluation in non-small cell lung cancer (NSCLC) and nasopharyngeal carcinoma (NPC). In Phase Ia, patients with advanced tumors received IBI318 doses ranging from 0.3 to 1200 mg every two weeks (Q2W) to determine the recommended Phase 2 dose (RP2D). In Phase Ib, NSCLC or NPC patients from five cohorts with varying treatment histories received IBI318 at the RP2D. The primary endpoint was safety and the secondary endpoints included efficacy assessed by investigators according to RECIST v1.1, pharmacokinetics, immunogenicity, and pharmacodynamics.

RESULTS

From February 11, 2019, to January 25, 2022, a total of 103 eligible patients were enrolled (Phase Ia, n = 55; Phase Ib, n = 48). The median follow-up was 10.1 months (range 0.7-28.6). The RP2D was determined to be 300 mg Q2W. Treatment-related adverse events (TRAEs) of any grades occurred in 88 patients (85.4%), while 10 patients (9.7%) experienced grade ≥ 3 TRAEs. The objective response rate (ORR) was 15.5% and the disease control rate (DCR) was 49.5% in all patients. In Phase Ib, the confirmed ORR was 45.5% in treatment-naïve NSCLC patients and 30.0% in IO-naïve NPC patients who had failed or were intolerant to platinum-based treatments.

CONCLUSIONS

IBI318 demonstrated a favorable safety profile and preliminary efficacy in treatment-naïve NSCLC and IO-naïve NPC patients. Further clinical studies are needed to assess the full therapeutic potential of PD-1/PD-L1 dual inhibition with bsAbs.

MT1E in AML: a gateway to understanding regulatory cell death and immunotherapeutic responses

Regulated cell death (RCD) plays a crucial role in the initiation and progression of tumors, particularly in acute myeloid leukemia (AML). This study investigates the prognostic importance of RCD-related genes in AML and their correlation with immune infiltration. We combined TCGA and GTEx data, analyzing 1,488 RCD-related genes, to develop a predictive model using LASSO regression and survival analysis. The model's accuracy was validated against multiple databases, examining immune cell infiltration, therapy responses, and drug sensitivity among risk groups. RT-qPCR confirmed MT1E expression in AML patients and healthy bone marrow. CCK8 and Transwell assays measured cell proliferation, adhesion, migration, and invasion, while flow cytometry and Western blotting assessed apoptosis and protein expression. We developed a prognostic model using 10 RCD methods, which demonstrated strong predictive ability, showing an inverse correlation between age and risk scores with survival in AML patients. Functional enrichment analysis of the model is linked to immune modulation pathways. RT-qPCR revealed significantly lower MT1E expression in AML vs healthy bone marrow (P < 0.05). Consequently, experiments were designed to assess the function of MT1E overexpression. Findings indicated that MT1E overexpression showed it significantly reduced THP-1 cell proliferation and adhesion (P < 0.001), decreased migration (P < 0.001), and invasiveness (P < 0.05), and increased apoptosis (P < 0.05), with a notable rise in Caspase3 expression. A novel AML RCD risk model was developed, showing promise as a prognostic marker for evaluating outcomes and immune therapy effectiveness. Insights into MT1E's impact on AML cell proliferation and apoptosis open possibilities for improving patient outcomes and devising personalized treatment strategies.

A surprising complete response to cadonilimab in a primary metastatic cervical cancer: a case report

The outcome of patients with recurrent/metastatic cervical cancer (R/M CC) is poor, with a 5-year survival rate of only 10%-20%. Recent advances in immunotherapy renewed its interest in R/M CC treatment. It has been suggested that cadonilimab, a novel bispecific antibody targeting programmed death 1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4), significantly improved the survival outcomes of the R/M CC. In the present study, we reported a programmed death ligand 1 (PD-L1) and human epidermal growth factor receptor 2 (HER-2) positive CC case at stage IV who was treated with cadonilimab and achieved a surprising radiographic complete response (CR) for 10 months, even in the PD-L1 negative metastatic site. Demographic, clinical, histopathological, laboratory, treatment regime and imaging data were recorded. Unfortunately, the patient progressed rapidly during maintenance therapy when cadonilimab was replaced by sintilimab, the monoclonal antibody against PD-1, indicating the more powerful anti-tumor activity of dual blockade immunotherapy. To conclude, cadonilimab offers a promising and effective therapeutic approach for R/M CC. Notably, HER-2 is also expected to be a new reference target for cadonilimab therapy.

Sequentially Activated Smart DNA Nanospheres for Photoimmunotherapy and Immune Checkpoint Blockade

Due to the inherent immunosuppression and immune evasion of cancer cells, combining photoimmunotherapy with immune checkpoint blockade leverages phototherapy and immune enhancement, overcoming mutual limitations and demonstrating significant anticancer potential. The main challenges include nonspecific accumulation of agents, uncontrolled activation, and drug carrier safety. Smart DNA nanospheres (NS) is developed with targeted delivery and controllable release of photosensitizers and immune agents to achieve effective synergistic therapy and minimize side effects. The multifunctional NS incorporate a targeting module for programming aptamers, a response module for programming i-motif and DNA/RNA hybrid sequences, and a therapeutic module for packaging photosensitizers and PD-L1 siRNA. NS navigate to the tumor site and are sequentially activated by intracellular acid and enzymes to release photosensitizers and programmed death ligand 1 (PD-L1) small interfering RNA (siRNA) programmed death protein 1 (PD-1) and programmed cell death ligands. Besides tumor killing and immune promotion, activated NS downregulate PD-L1 expression, alleviating immune tolerance and evasion, thus enhancing the immune response. These results indicate that NS significantly enhance antitumor immune responses, synergistically improve antitumor efficacy, and reduce systemic toxicity. This study broadens the application of DNA nanomaterials in precision drug delivery and tumor therapy.

Bacterial membrane vesicles combined with nanoparticles for bacterial vaccines and cancer immunotherapy

Similar to mammalian cells, most bacteria can release nano-sized membrane vesicles (MVs) into the extracellular environment. MVs contain lipids, bioactive proteins, nucleic acids, and metabolites, and play important roles in microbial physiology. MVs have great potential for immunotherapeutic applications, such as bacterial vaccines and cancer immunotherapy. However, because of the diversity in content and heterogeneity in size of MVs, the clinical application of MVs has been limited. Recently, the use of MVs combined with nanoparticles (NPs) has been shown to be effective in improving the homogeneity, stability and function of MVs. In this review, we focus on studies of MVs combined with NPs (MV-NPs) and describe the use of these MV-NPs in biotechnology, especially in bacterial vaccine and cancer immunotherapy.

The Rational Engineered Bacteria Based Biohybrid Living System for Tumor Therapy

Living therapy based on bacterial cells has gained increasing attention for their applications in tumor treatments. Bacterial cells can naturally target to tumor sites and active the innate immunological responses. The intrinsic advantages of bacteria attribute to the development of biohybrid living carriers for targeting delivery toward hypoxic environments. The rationally engineered bacterial cells integrate various functions to enhance the tumor therapy and reduce toxic side effects. In this review, the antitumor effects of bacteria and their application are discussed as living therapeutic agents across multiple antitumor platforms. The various kinds of bacteria used for cancer therapy are first introduced and demonstrated the mechanism of antitumor effects as well as the immunological effects. Additionally, this study focused on the genetically modified bacteria for the production of antitumor agents as living delivery system to treat cancer. The combination of living bacterial cells with functional nanomaterials is then discussed in the cancer treatments. In brief, the rational design of living therapy based on bacterial cells highlighted a rapid development in tumor therapy and pointed out the potentials in clinical applications.

Ginsenoside Rg3 activates the immune function of CD8+ T cells via circFOXP1-miR-4477a-PD-L1 axis to induce ferroptosis in gallbladder cancer

Gallbladder cancer (GBC) is the most common and leading cause of cancer-associated mortality among biliary tract carcinomas worldwide and there is no specific drug for treatment. Activation of CD8+ T cell immune activity is one of the strategies to improve GBC treatment. This study is aimed to investigate the role of Ginsenoside Rg3 on CD8+ T cell activation and pathogenesis of GBC. In GBC cells, Rg3 administration led to the significant reduction of circFOXP1 and PD-L1 as measured by Quantitative real-time polymerase chain reaction (RT-qPCR) and Western blotting. Mechanistically, circFOXP1 acted as the sponge of miR-4477a to regulate PD-L1 expression as demonstrated by RNA pull-down assay and dual luciferase reporter assay. Rg3 treatment enhanced the activity of CD8+ T cells by inhibiting the circFOXP1/miR-4477a/PD-L1 signaling axis. Besides, Rg3 administration induced lipid oxidation and ROS reduction as detected by Flow cytometry, resulting in ferroptosis via the inactivation of circFOXP1/miR-4477a/PD-L1 axis. Ferroptosis inhibitor Fer-1 administration could reverse the beneficial effects caused by Rg3 treatment while ferroptosis inducer Erastin treatment enhanced the effects. Moreover, Rg3 gavage alleviated tumor growth and elevated ferroptosis and apoptosis in tumor tissues, which were prevented by PD-L1 overexpression. Furthermore, Rg3 was demonstrated to activate the function of CD8+ T cells via regulating the circFOXP1-miR-4477a-PD-L1 signaling axis in vivo. Rg3 inactivated the circFOXP1-miR-4477a-PD-L1 signaling axis to activate the immune function of CD8+ T cells, thereby inducing ferroptosis and apoptosis in GBC cells. This research recognizes the mechanism of Rg3-mediated anti-cancer effect and offers evidence for the potentiality of Rg3 in clinical application for GBC therapy.

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

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

Programmed death receptor-1/programmed death-ligand 1 inhibitors: Clinical progress and biomarker exploration in gastric cancer

Gastric cancer is one of the most common malignant tumours, with limited treatment options and poor prognosis in its advanced stages. In recent years, breakthroughs in tumour immunotherapy have led to immune checkpoint inhibitors becoming a new class of clinical oncology drugs. Programmed death receptor-1 (PD-1) and programmed death-ligand 1 (PD-L1) play significant roles in inhibiting T cell responses and tumour immune escape. PD-1/PD-L1 inhibitors can significantly improve the prognosis of patients with advanced gastric cancer. Moreover, the combination of administering PD-1/PD-L1 inhibitors along with chemotherapy, radiotherapy, targeted therapy, and other immunotherapies may further enhance therapeutic efficacy. However, some scientific issues need to be urgently resolved in the immunotherapy of gastric cancer, including the suboptimal efficacy of PD-1/PD-L1 inhibitor monotherapy, high incidence of immune-related adverse events, and the absence of definitive biomarkers for effectively screening treatment-sensitive populations. This article reviews the mechanism of action, therapeutic advances, adverse effects, and putative predictive biomarkers of PD-1/PD-L1 inhibitors in the treatment of advanced gastric cancer.

O-GlcNAcylation of enolase 1 serves as a dual regulator of aerobic glycolysis and immune evasion in colorectal cancer

Aerobic glycolysis and immune evasion are two key hallmarks of cancer. However, how these two features are mechanistically linked to promote tumor growth is not well understood. Here, we show that the glycolytic enzyme enolase-1 (ENO1) is dynamically modified with an O-linked β-N-acetylglucosamine (O-GlcNAcylation), and simultaneously regulates aerobic glycolysis and immune evasion via differential glycosylation. Glycosylation of threonine 19 (T19) on ENO1 promotes its glycolytic activity via the formation of active dimers. On the other hand, glycosylation of serine 249 (S249) on ENO1 inhibits its interaction with PD-L1, decreases association of PD-L1 with the E3 ligase STUB1, resulting in stabilization of PD-L1. Consequently, blockade of T19 glycosylation on ENO1 inhibits glycolysis, and decreases cell proliferation and tumor growth. Blockade of S249 glycosylation on ENO1 reduces PD-L1 expression and enhances T cell-mediated immunity against tumor cells. Notably, elimination of glycosylation at both sites synergizes with PD-L1 monoclonal antibody therapy to promote antitumor immune response. Clinically, ENO1 glycosylation levels are up-regulated and show a positive correlation with PD-L1 levels in human colorectal cancers. Thus, our findings provide a mechanistic understanding of how O-GlcNAcylation bridges aerobic glycolysis and immune evasion to promote tumor growth, suggesting effective therapeutic opportunities.

Co-inhibition of PGF and VEGFA enhances the effectiveness of immunotherapy in bladder cancer

Background: Anti-angiogenic inhibitors and immune checkpoint blockade combination therapy offers a novel approach to circumvent the challenges associated with limited responsiveness to checkpoint inhibitors in bladder cancer. However, the effective strategies for inhibiting angiogenesis in bladder cancer need further elucidation. Objective: This work aims to identify key targets for the effective inhibition of angiogenesis in bladder cancer and to explore the potential benefits of combining anti-angiogenic therapies with immune checkpoint blockade strategies in the treatment of this disease. Methods: Cell-cell interaction analysis was performed using bladder cancer single-cell transcriptome datasets downloaded from the Gene Expression Omnibus (GEO) database to determine the regulatory network driving angiogenesis in bladder cancer. The bladder cancer cell line MBT2 was orthotopically transplanted into mice to investigate the impact of pro-angiogenic molecules on angiogenesis and tumor growth, and to evaluate the synergistic therapeutic potential of a combination therapy targeting angiogenesis and Programmed Cell Death Protein 1 (PD-1). Proliferation and tube formation assays with Human Umbilical Vein Endothelial Cells (HUVECs) were used to explore the regulatory functions of pro-angiogenic molecules in angiogenesis. Results: Placental growth factor (PGF) is a pro-angiogenic factor in bladder cancer, in addition to vascular endothelial growth factor A (VEGFA). Suppression of PGF reduced the tumor size and angiogenesis in bladder cancer. The expression level of vascular endothelial growth factor receptor 1 (VEGFR1) is higher than that of vascular endothelial growth factor receptor2 (VEGFR2) in the endothelial cells of bladder cancer. The pro-angiogenic activity of PGF is dependent on the expression level of VEGFR1 in endothelial cells. The combined inhibition of PGF and VEGFA exerts a synergistic effect on suppressing tumor growth and angiogenesis. The concurrent inhibition of PGF and VEGFA stands out as the only intervention capable of significantly enhancing the infiltration of CD8+ cytotoxic T cells within the bladder cancer microenvironment. In the bladder cancer mouse model, the introduction of an anti- programmed cell death protein 1 (PD-1) therapeutic regimen combined with the targeted inhibition of PGF and VEGFA, led to a significantly elevated survival rate compared to the outcome observed with anti-PD-1 monotherapy. Conclusion: PGF is a pro-angiogenic molecule in bladder cancer that requires significant expression levels of VEGFR1 in endothelial cells. Notably, the concurrent inhibition of PGF and VEGFA amplifies the therapeutic impact of anti-PD-1 treatment in bladder cancer. These findings provide further insights into the role of PGF in angiogenesis regulation and have conceptual implications for combining anti-angiogenic therapy with immune therapy in bladder cancer treatment.

Tumour Immunotherapy and Applications of Immunological Products: A Review of Literature

Malignant tumors, characterized by uncontrolled cell proliferation, are a leading global health challenge, responsible for over 9.7 million deaths in 2022, with new cases expected to rise to 35 million annually by 2050. Immunotherapy is preferred to other cancer therapies, offering precise targeting of malignant cells while simultaneously strengthening the immune system's complex responses. Advances in this novel field of science have been closely linked to a deeper knowledge of tumor biology, particularly the intricate interplay between tumor cells, the immune system, and the tumor microenvironment (TME), which are central to cancer progression and immune evasion. This review offers a comprehensive analysis of the molecular mechanisms that govern these interactions, emphasizing their critical role in the development of effective immunotherapeutic products. We critically evaluate the current immunotherapy approaches, including cancer vaccines, adoptive T cell therapies, and cytokine-based treatments, highlighting their efficacy and safety. We also explore the latest advancements in combination therapies, which synergistically integrate multiple immunotherapeutic strategies to overcome resistance and enhance therapeutic outcomes. This review offers key insights into the future of cancer immunotherapy with a focus on advancing more effective and personalized treatment strategies.

SPI1+CD68+ macrophages as a biomarker for gastric cancer metastasis: a rationale for combined antiangiogenic and immunotherapy strategies

BACKGROUND

Tumor-associated macrophages (TAMs) have been demonstrated to be associated with tumor progression. However, the different subpopulations of TAMs and their roles in gastric cancer (GC) remain poorly understood. This study aims to assess the effects of Spi-1 proto-oncogene (SPI1)+CD68+ TAMs in GC.

METHODS

The distribution of SPI1+CD68+ TAMs in GC tissue was estimated by immunohistochemistry, immunofluorescence, and flow cytometry. Single-cell transcriptome analysis and multiplex fluorescence immunohistochemistry were applied to explore the role of SPI1+CD68+ TAMs in an immune contexture. SPI1 overexpression or knockdown cells were constructed to evaluate its role in macrophage polarization and angiogenesis in vitro and in vivo. Chromatin immunoprecipitation was used to verify the mechanism of SPI1 transcriptional function. The effect of combined antiangiogenic and immunotherapy was further validated using mouse peritoneal metastasis models.

RESULTS

Single-cell transcriptome analysis and immunohistochemistry demonstrated that SPI1 was expressed in macrophages, with a higher enrichment in metastatic lesions than in primary tumors. Higher SPI1+CD68+ TAMs infiltration was associated with poor overall survival. Mechanically, SPI1 promoted the M2-type macrophage polarization. SPI1 could bind to the promoter of vascular endothelial growth factor A and facilitate angiogenesis. Moreover, the level of SPI1+CD68+ TAMs infiltration was closely related to the efficacy of immunotherapy, especially when combined with antiangiogenic therapy.

CONCLUSIONS

The present study showed that SPI1+CD68+ TAMs are a promising biomarker for predicting prognosis, antiangiogenic drug sensitivity, and combination target of immunotherapy in patients with GC.

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

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

Advances in targeting tumor microenvironment for immunotherapy

The tumor microenvironment (TME) provides essential conditions for the occurrence, invasion, and spread of cancer cells. Initial research has uncovered immunosuppressive properties of the TME, which include low oxygen levels (hypoxia), acidic conditions (low pH), increased interstitial pressure, heightened permeability of tumor vasculature, and an inflammatory microenvironment. The presence of various immunosuppressive components leads to immune evasion and affects immunotherapy efficacy. This indicates the potential value of targeting the TME in cancer immunotherapy. Therefore, TME remodeling has become an effective method for enhancing host immune responses against tumors. In this study, we elaborate on the characteristics and composition of the TME and how it weakens immune surveillance and summarize targeted therapeutic strategies for regulating the TME.

Specific targeting of cancer vaccines to antigen-presenting cells via an endogenous TLR2/6 ligand derived from cysteinyl-tRNA synthetase 1

Cancer vaccines have been developed as a promising way to boost cancer immunity. However, their clinical potency is often limited due to the imprecise delivery of tumor antigens. To overcome this problem, we conjugated an endogenous Toll-like receptor (TLR)2/6 ligand, UNE-C1, to human papilloma virus type 16 (HPV-16)-derived peptide antigen, E7, and found that the UNE-C1-conjugated cancer vaccine (UCV) showed significantly enhanced antitumor activity in vivo compared with the noncovalent combination of UNE-C1 and E7. The combination of UCV with PD-1 blockades further augmented its therapeutic efficacy. Specifically, the conjugation of UNE-C1 to E7 enhanced its retention in inguinal draining lymph nodes, the specific delivery to dendritic cells and E7 antigen-specific T cell responses, and antitumor efficacy in vivo compared with the noncovalent combination of the two peptides. These findings suggest the potential of UNE-C1 derived from human cysteinyl-tRNA synthetase 1 as a unique vehicle for the specific delivery of cancer antigens to antigen-presenting cells via TLR2/6 for the improvement of cancer vaccines.

Recent updates in the therapeutic uses of Pembrolizumab: a brief narrative review

INTRODUCTION

Treatment of cancer has been improved with the discovery of biological drugs that act as immune checkpoint inhibitors. In 2017, FDA designated pembrolizumab, an immune checkpoint inhibitor employed in immunotherapy, as the first tissue-agnostic cancer treatment.

OBJECTIVES

To review pembrolizumab's use in oncology, gather and examine the latest discoveries regarding the effectiveness of pembrolizumab in cancer treatment.

METHODOLOGY

A literature review was conducted through PubMed(Medline) from January 2015 to December 2023 using "pembrolizumab", "cancer" and "treatment" as search terms.

RESULTS

Pembrolizumab demonstrated effectiveness as primary treatment for metastatic nonsmall cell lung cancer, unresectable esophageal cancer, head and neck squamous cell carcinoma and alternative treatment for notable triple-negative breast cancer, biliary, colorectal, endometrial, renal cell, cervical carcinoma, and high microsatellite instability or mismatch repair deficiencies tumors. Pediatric applications include treatment for refractory Hodgkin lymphoma.

CONCLUSION

Evolving research on pembrolizumab allows a deeper clinical understanding, despite challenges as variable patient responses. Pembrolizumab has emerged as a pivotal breakthrough in cancer treatment, improving patient outcomes and safety.

Anti-PD-L1 checkpoint inhibitor combined with nanocarrier-mediated cisplatin codelivery system for effective treatment of pancreatic cancer

Immune checkpoint inhibitor-based cancer immunotherapy has shown promise as a potential treatment in the clinic. It has been reported that anti-PD-L1 combined with cisplatin treatment can improve the antitumor effect. However, the therapeutic outcome is limited due to the abundance of tumor stroma in pancreatic cancer (PC), which prevented the penetration of cisplatin and anti-PD-L1 into tumor regions, thus impeding the effectiveness in the treatment of PC. In this study, a nanocarrier-mediated codelivery system of hyaluronidase and cisplatin was constructed, which can degrade the stroma and promote cisplatin and anti-PD-L1 to penetrate the tumor stroma into the deep tumor, so as to suppress PC effectively. When combined the cisplatin nanocarrier system BPEI-SS-Pt/HAase@CaP (BSP/H@CaP) with an immune checkpoint inhibitor to overcome the poor therapeutic outcome of PC, the results indicated that the therapeutic effect of BSP/H@CaP combined with anti-PD-L1 was better than that of BSP/H@CaP and single anti-PD-L1 group. Because the stroma is degrading, a higher amount of BPEI-SS-Pt and anti-PD-L1 can enter the tumor stroma and reach the inner depths of the tumor for immune stimulation, leading to a synergistically augmented chemotherapy and immunotherapy for PC. The above combination therapy is useful for clinical translation to overcome the treatment resistance of matrix-rich PC.

Comprehensive review of drug-mediated ICD inhibition of breast cancer: mechanism, status, and prospects

The escalating incidence of breast cancer (BC) in women underscores its grave health threat. Current molecular insights into BC's post-adjuvant therapy cure remain elusive, necessitating active treatment explorations. Immunotherapy, notably chemotherapy-induced immunogenic cell death (ICD), has emerged as a promising BC therapy. ICD harnesses chemotherapeutics to activate anti-tumor immunity via DAMPs, fostering long-term T-cell memory and primary BC cure. Besides chemotherapy drugs, Nanodrugs, traditional Chinese medicine (TCM) and ICIs also induce ICD, boosting immune response. ICIs, like PD-1/PD-L1 inhibitors, revolutionize cancer treatment but face limited success in cold tumors. Thus, ICD induction combined with ICIs is studied extensively for BC immunotherapy. This article reviews the mechanism of ICD related drugs in BC and provides reference for the research and development of BC treatment, in order to explore more effective clinical treatment of BC, we hope to explore more ICD inducers and make ICIs more effective vaccines.

Colorectal cancer: Recent advances in management and treatment

Colorectal cancer (CRC) is the third most common cancer worldwide, and the second most common cause of cancer-related death. In 2020, the estimated number of deaths due to CRC was approximately 930000, accounting for 10% of all cancer deaths worldwide. Accordingly, there is a vast amount of ongoing research aiming to find new and improved treatment modalities for CRC that can potentially increase survival and decrease overall morbidity and mortality. Current management strategies for CRC include surgical procedures for resectable cases, and radiotherapy, chemotherapy, and immunotherapy, in addition to their combination, for non-resectable tumors. Despite these options, CRC remains incurable in 50% of cases. Nonetheless, significant improvements in research techniques have allowed for treatment approaches for CRC to be frequently updated, leading to the availability of new drugs and therapeutic strategies. This review summarizes the most recent therapeutic approaches for CRC, with special emphasis on new strategies that are currently being studied and have great potential to improve the prognosis and lifespan of patients with CRC.

USP18 Is Associated with PD-L1 Antitumor Immunity and Improved Prognosis in Colorectal Cancer

BACKGROUND

Compared with conventional chemotherapy and targeted therapy, immunotherapy has improved the treatment outlook for a variety of solid tumors, including lung cancer, colorectal cancer (CRC), and melanoma. However, it is effective only in certain patients, necessitating the search for alternative strategies to targeted immunotherapy. The deubiquitinating enzyme USP18 is known to play an important role in various aspects of the immune response, but its role in tumor immunity in CRC remains unclear.

METHODS

In this study, multiple online datasets were used to systematically analyze the expression, prognosis, and immunomodulatory role of USP18 in CRC. The effect of USP18 on CRC was assessed via shRNA-mediated knockdown of USP18 expression in combination with CCK-8 and colony formation assays. Finally, molecular docking analysis of USP18/ISG15 and programmed death-ligand 1 (PD-L1) was performed via HDOCK, and an ELISA was used to verify the potential of USP18 to regulate PD-L1.

RESULTS

Our study revealed that USP18 expression was significantly elevated in CRC patients and closely related to clinicopathological characteristics. The experimental data indicated that silencing USP18 significantly promoted the proliferation and population-dependent growth of CRC cells. In addition, high USP18 expression was positively correlated with the CRC survival rate and closely associated with tumor-infiltrating CD8+ T cells and natural killer (NK) cells. Interestingly, USP18 was correlated with the expression of various chemokines and immune checkpoint genes. The results of molecular docking simulations suggest that USP18 may act as a novel regulator of PD-L1 and that its deficiency may potentiate the antitumor immune response to PD-L1 blockade immunotherapy in CRC.

CONCLUSIONS

In summary, USP18 shows great promise for research and clinical application as a potential target for CRC immunotherapy.

Nanotechnology in Advancing Chimeric Antigen Receptor T Cell Therapy for Cancer Treatment

Chimeric antigen receptor (CAR) T cell therapy has emerged as a groundbreaking treatment for hematological cancers, yet it faces significant hurdles, particularly regarding its efficacy in solid tumors and concerning associated adverse effects. This review provides a comprehensive analysis of the advancements and ongoing challenges in CAR-T therapy. We highlight the transformative potential of nanotechnology in enhancing CAR-T therapy by improving targeting precision, modulating the immune-suppressive tumor microenvironment, and overcoming physical barriers. Nanotechnology facilitates efficient CAR gene delivery into T cells, boosting transfection efficiency and potentially reducing therapy costs. Moreover, nanotechnology offers innovative solutions to mitigate cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Cutting-edge nanotechnology platforms for real-time monitoring of CAR-T cell activity and cytokine release are also discussed. By integrating these advancements, we aim to provide valuable insights and pave the way for the next generation of CAR-T cell therapies to overcome current limitations and enhance therapeutic outcomes.

Novel insights into the regulation of exosomal PD-L1 in cancer: From generation to clinical application

Programmed cell death ligand 1 (PD-L1) interacts with programmed cell death 1 (PD-1), leading to T cell exhaustion and promoting tumor cell survival, ultimately mediating immunosuppression. While FDA-approved monoclonal antibodies targeting the PD-1/PD-L1 interaction have shown success in cancer treatment, some patients experience limited and short-lived therapeutic outcomes. Recent studies have identified PD-L1 expression not only on tumor cell surfaces but also on exosomes, with secretion pathways including both conventional and unconventional endocytosis routes, presenting a unique therapeutic opportunity. Emerging evidence suggests that exosomal PD-L1 contributes to systemic immunosuppression, potentially counteracting the effects of anti-PD-1 checkpoint therapies. However, the significance of exosomal PD-L1 in clinical cancer patients unresponsive to anti-PD-1/PD-L1 immunotherapy, as well as the factors regulating its generation, remain unclear. Moreover, the mechanisms underlying PD-L1 expression on exosomes and its regulation in cancer are yet to be fully elucidated. This review primarily focuses on the mechanisms modulating exosomal PD-L1 generation in cancer, while also outlining its involvement in immunosuppression, tumor proliferation, and response to cancer immunotherapy. Additionally, we explore the potential of exosomal PD-L1 as a cancer biomarker and therapeutic target, aiming to provide a comprehensive overview of this emerging field and its implications for cancer treatment and diagnosis.

What is the Reason That the Pharmacological Future of Chemotherapeutics in the Treatment of Lung Cancer Could Be Most Closely Related to Nanostructures? Platinum Drugs in Therapy of Non-Small and Small Cell Lung Cancer and Their Unexpected, Possible Interactions. The Review

Over the course of several decades, anticancer treatment with chemotherapy drugs for lung cancer has not changed significantly. Unfortunately, this treatment prolongs the patient's life only by a few months, causing many side effects in the human body. It has also been proven that drugs such as Cisplatin, Carboplatin, Oxaliplatin and others can react with other substances containing an aromatic ring in which the nitrogen atom has a free electron group in its structure. Thus, such structures may have a competitive effect on the nucleobases of DNA. Therefore, scientists are looking not only for new drugs, but also for new alternative ways of delivering the drug to the cancer site. Nanotechnology seems to be a great hope in this matter. Creating a new nanomedicine would reduce the dose of the drug to an absolute minimum, and thus limit the toxic effect of the drug; it would allow for the exclusion of interactions with competitive compounds with a structure similar to nucleobases; it would also permit using the so-called targeted treatment and bypassing healthy cells; it would allow for the introduction of other treatment options, such as radiotherapy directly to the cancer site; and it would provide diagnostic possibilities. This article is a review that aims to systematize the knowledge regarding the anticancer treatment of lung cancer, but not only. It shows the clear possibility of interactions of chemotherapeutics with compounds competitive to the nitrogenous bases of DNA. It also shows the possibilities of using nanostructures as potential Platinum drug carriers, and proves that nanomedicine can easily become a new medicinal product in personalized medicine.

Model-informed drug development of envafolimab, a subcutaneously injectable PD-L1 antibody, in patients with advanced solid tumors

BACKGROUND AND OBJECTIVES

Envafolimab is the first and only globally approved subcutaneously injectable PD-L1 antibody for the treatment of instability-high (MSI-H) or DNA mismatch repair deficient (dMMR) advanced solid tumors in adults, including those with advanced colorectal cancer that has progressed after treatment with a fluoropyrimidine, oxaliplatin, and irinotecan. The aim of this investigation was to examine the pharmacokinetic and exposure-response (E-R) profile of envafolimab in patients with solid tumors to support the approval of fixed and alternative dose regimens.

METHODS

In this study, a population pharmacokinetic (PopPK) modeling approach will be employed to quantitatively evaluate intrinsic and extrinsic covariates. Additionally, PopPK-estimated exposure parameters were used to evaluate E-R relationship for safety and efficacy to provide a theoretical basis for recommending optimal treatment regimens. Simulations were performed on the dosing regimens of body weight-based regimen of 2.50 mg/kg QW, fixed dose 150 mg QW, and 300 mg Q2W for the selection of alternative dosing regimens. Data from 4 clinical studies (NCT02827968, NCT03101488, NCT03248843, and NCT03667170) were utilized.

RESULTS

The PopPK dataset comprised 182 patients with 1810 evaluable envafolimab concentration records. Finally, a one-compartment model incorporating first-order absorption, first-order linear elimination, and time-dependent elimination according to an Emax function was found to accurately describe the concentration-time data of envafolimab in patients with advanced solid tumors. Creatinine clearance and country were identified as statistically significant factors affecting clearance, but had limited clinical significance. A relative flat exposure-response relationship was observed between early measures of safety and efficacy to verify that no dose adjustment is required. Simulation results indicated that 2.50 mg/kg QW, 150 mg QW, and 300 mg Q2W regimen yield similar steady-state exposure.

CONCLUSIONS

No statistically significant difference was observed between weight-based and fixed dose regimens. Model-based simulation supports the adoption of a 150 mg weekly or 300 mg biweekly dosing regimen of envafolimab in the solid tumor population, as these schedules effectively balance survival benefits and safety risks.

Programmed death receptor (PD-)1/PD-ligand (L)1 in urological cancers : the "all-around warrior" in immunotherapy

Programmed death receptor-1 (PD-1) and its ligand, programmed death ligand-1 (PD-L1) are essential molecules that are key in modulating immune responses. PD-L1 is constitutively expressed on various immune cells, epithelial cells, and cancer cells, where it functions as a co-stimulatory molecule capable of impairing T-cell mediated immune responses. Upon binding to PD-1 on activated T-cells, the PD-1/PD-L1 interaction triggers signaling pathways that can induce T-cell apoptosis or anergy, thereby facilitating the immune escape of tumors. In urological cancers, including bladder cancer (BCa), renal cell carcinoma (RCC), and prostate cancer (PCa), the upregulation of PD-L1 has been demonstrated. It is linked to poor prognosis and enhanced tumor immune evasion. Recent studies have highlighted the significant role of the PD-1/PD-L1 axis in the immune escape mechanisms of urological cancers. The interaction between PD-L1 and PD-1 on T-cells further contributes to immunosuppression by inhibiting T-cell activation and proliferation. Clinical applications of PD-1/PD-L1 checkpoint inhibitors have shown promising efficacy in treating advanced urological cancers, significantly improving patient outcomes. However, resistance to these therapies, either intrinsic or acquired, remains a significant challenge. This review aims to provide a comprehensive overview of the role of the PD-1/PD-L1 signaling pathway in urological cancers. We summarize the regulatory mechanism underlying PD-1 and PD-L1 expression and activity, including genetic, epigenetic, post-transcriptional, and post-translational modifications. Additionally, we discuss current clinical research on PD-1/PD-L1 inhibitors, their therapeutic potential, and the challenges associated with resistance. Understanding these mechanisms is crucial for developing new strategies to overcome therapeutic limitations and enhance the efficacy of cancer immunotherapy.

LAMTOR1 decreased exosomal PD-L1 to enhance immunotherapy efficacy in non-small cell lung cancer

Great progress has been made in utilizing immune checkpoint blockade (ICB) for the treatment of non-small-cell lung cancer (NSCLC). Therapies targeting programmed cell death protein 1 (PD-1) and its ligand PD-L1, expressed on tumor cells, have demonstrated potential in improving patient survival rates. An unresolved issue involves immune suppression induced by exosomal PD-L1 within the tumor microenvironment (TME), particularly regarding CD8+ T cells. Our study unveiled the crucial involvement of LAMTOR1 in suppressing the exosomes of PD-L1 and promoting CD8+ T cell infiltration in NSCLC. Through its interaction with HRS, LAMTOR1 facilitates PD-L1 lysosomal degradation, thereby reducing exosomal PD-L1 release. Notably, the ability of LAMTOR1 to promote PD-L1 lysosomal degradation relies on a specific ubiquitination site and an HRS binding sequence. The findings suggest that employing LAMTOR1 to construct peptides could serve as a promising strategy for bolstering the efficacy of immunotherapy in NSCLC. The discovery and comprehension of how LAMTOR1 inhibits the release of exosomal PD-L1 offer insights into potential therapeutic strategies for improving immunotherapy. It is imperative to conduct further research and clinical trials to investigate the feasibility and efficacy of targeting LAMTOR1 in NSCLC treatment.

Immune checkpoint reprogramming via sequential nucleic acid delivery strategy optimizes systemic immune responses for gastrointestinal cancer immunotherapy

Monoclonal antibodies targeting immune checkpoints have been widely applied in gastrointestinal cancer immunotherapy. However, systemic administration of various monoclonal antibodies does not often result in sustained effects in reversing the immunosuppressive tumor microenvironment (TME), which may be due to the spatiotemporal dynamic changes of immune checkpoints. Herein, we reported a novel immune checkpoint reprogramming strategy for gastrointestinal cancer immunotherapy. It was achieved by the sequential delivery of siPD-L1 (siRNA for programmed cell death ligand 1) and pOX40L (plasmid for OX40 ligand), which were complexed with two cationic polymer brush-grafted carbon nanotubes (dense short (DS) and dense long (DL)) designed based on the structural characteristics of nucleic acids and brush architectures. Upon administrating DL/pOX40L for the first three dosages, then followed by DS/siPD-L1 for the next three dosages to the TME, it upregulated the stimulatory checkpoint OX40L on dendritic cells (DCs) and downregulated inhibitory checkpoint PD-L1 on tumor cells and DCs in a sequential reprogramming manner. Compared with other combination treatments, this sequential strategy drastically boosted the DCs maturation, and CD8+ cytotoxic T lymphocytes infiltration in tumor site. Furthermore, it could augment the local antitumor response and improve the T cell infiltration in tumor-draining lymph nodes to reverse the peripheral immunosuppression. Our study demonstrated that sequential nucleic acid delivery strategy via personalized nanoplatforms effectively reversed the immunosuppression status in both tumor microenvironment and peripheral immune landscape, which significantly enhanced the systemic antitumor immune responses and established an optimal immunotherapy strategy against gastrointestinal cancer.

Immunostimulatory CKb11 gene combined with immune checkpoint PD-1/PD-L1 blockade activates immune response and simultaneously overcomes the immunosuppression of cancer

Immunosuppression tumor microenvironment (TME) seriously impedes anti-tumor immune response, resulting in poor immunotherapy effect of cancer. This study develops a folate-modified delivery system to transport the plasmids encoding immune stimulatory chemokine CKb11 and PD-L1 inhibitors to tumor cells, resulting in high CKb11 secretion from tumor cells, successfully activating immune cells and increasing cytokine secretion to reshape the TME, and ultimately delaying tumor progression. The chemokine CKb11 enhances the effectiveness of tumor immunotherapy by increasing the infiltration of immune cells in TME. It can cause high expression of IFN-γ, which is a double-edged sword that inhibits tumor growth while causing an increase in the expression of PD-L1 on tumor cells. Therefore, combining CKb11 with PD-L1 inhibitors can counterbalance the suppressive impact of PD-L1 on anti-cancer defense, leading to a collaborative anti-tumor outcome. Thus, utilizing nanotechnology to achieve targeted delivery of immune stimulatory chemokines and immune checkpoint inhibitors to tumor sites, thereby reshaping immunosuppressive TME for cancer treatment, has great potential as an immunogene therapy in clinical applications.

PAK4 Is Involved in the Stabilization of PD-L1 and the Resistance to Doxorubicin in Osteosarcoma and Predicts the Survival of Diagnosed Patients

PAK4 and PD-L1 have been suggested as novel therapeutic targets in human cancers. Moreover, PAK4 has been suggested to be a molecule closely related to the immune evasion of cancers. Therefore, this study evaluated the roles of PAK4 and PD-L1 in the progression of osteosarcomas in 32 osteosarcomas and osteosarcoma cells. In human osteosarcomas, immunohistochemical positivity for the expression of PAK4 (overall survival, p = 0.028) and PD-L1 (relapse-free survival, p = 0.002) were independent indicators for the survival of patients in a multivariate analysis. In osteosarcoma cells, the overexpression of PAK4 increased proliferation and invasiveness, while the knockdown of PAK4 suppressed proliferation and invasiveness. The expression of PAK4 was associated with the expression of the molecules related to cell cycle regulation, invasion, and apoptosis. PAK4 was involved in resistance to apoptosis under a treatment regime with doxorubicin for osteosarcoma. In U2OS cells, PAK4 was involved in the stabilization of PD-L1 from ubiquitin-mediated proteasomal degradation and the in vivo infiltration of immune cells such as regulatory T cells and PD1-, CD4-, and CD8-positive cells in mice tumors. In conclusion, this study suggests that PAK4 is involved in the progression of osteosarcoma by promoting proliferation, invasion, and resistance to doxorubicin and stabilized PD-L1 from proteasomal degradation.

Overcoming Resistance to Checkpoint Inhibitors with Combination Strategies in the Treatment of Non-Small Cell Lung Cancer

Lung cancer continues to contribute to the highest percentage of cancer-related deaths worldwide. Advancements in the treatment of non-small cell lung cancer like immune checkpoint inhibitors have dramatically improved survival and long-term disease response, even in curative and perioperative settings. Unfortunately, resistance develops either as an initial response to treatment or more commonly as a progression after the initial response. Several modalities have been utilized to combat this. This review will focus on the various combination treatments with immune checkpoint inhibitors including the addition of chemotherapy, various immunotherapies, radiation, antibody-drug conjugates, bispecific antibodies, neoantigen vaccines, and tumor-infiltrating lymphocytes. We discuss the status of these agents when used in combination with immune checkpoint inhibitors with an emphasis on lung cancer. The early toxicity signals, tolerability, and feasibility of implementation are also reviewed. We conclude with a discussion of the next steps in treatment.

Combined strategies with PARP inhibitors for the treatment of BRCA wide type cancer

Genomic instability stands out as a pivotal hallmark of cancer, and PARP inhibitors (PARPi) emerging as a groundbreaking class of targeted therapy drugs meticulously crafted to inhibit the repair of DNA single-strand breaks(SSB) in tumor cells. Currently, PARPi have been approved for the treatment of ovarian cancer, pancreatic cancer, breast cancer, and prostate cancer characterized by homologous recombination(HR) repair deficiencies due to mutations in BRCA1/2 or other DNA repair associated genes and acquiring the designation of breakthrough therapy. Nonetheless, PARPi exhibit limited efficacy in the majority of HR-proficient BRCA1/2 wild-type cancers. At present, the synergistic approach of combining PARPi with agents that induce HR defects, or with chemotherapy and radiotherapy to induce substantial DNA damage, significantly enhances the efficacy of PARPi in BRCA wild-type or HR-proficient patients, supporting extension the use of PARPi in HR proficient patients. Therefore, we have summarized the effects and mechanisms of the combined use of drugs with PARPi, including the combination of PARPi with HR defect-inducing drugs such as ATRi, CHKi, HR indirectly inducing drugs like VEGFRi, CDKi, immune checkpoint inhibitors and drugs instigating DNA damage such as chemotherapy or radiotherapy. In addition, this review discusses several ongoing clinical trials aimed at analyzing the clinical application potential of these combined treatment strategies.

A viable remedy for overcoming resistance to anti-PD-1 immunotherapy: Fecal microbiota transplantation

Anti-PD-1 immunotherapy is a cancer therapy that focuses explicitly on the PD-1 receptor found on the surface of immune cells. This targeted therapeutic strategy is specifically designed to amplify the immune system's innate capacity to detect and subsequently eliminate cells that have become cancerous. Nevertheless, it should be noted that not all patients exhibit a favourable response to this particular therapeutic modality, necessitating the exploration of novel strategies to augment the effectiveness of immunotherapy. Previous studies have shown that fecal microbiota transplantation (FMT) can enhance the efficacy of anti-PD-1 immunotherapy in advanced melanoma patients. To investigate this intriguing possibility further, we turned to PubMed and conducted a comprehensive search for studies that analyzed the interplay between FMT and anti-PD-1 therapy in the context of tumor treatment. Our search criteria were centred around two key phrases: "fecal microbiota transplantation" and "anti-PD-1 therapy." The studies we uncovered all echo a similar sentiment. They pointed towards the potential of FMT to improve the effectiveness of immunotherapy. FMT may enhance the effectiveness of immunotherapy by altering the gut microbiota and boosting the patient's immunological response. Although promising, additional investigation is needed to improve the efficacy of FMT in the context of cancer therapy and attain a comprehensive understanding of the possible advantages and drawbacks associated with this therapeutic strategy.

Immunosuppressive tumor microenvironment in the progression, metastasis, and therapy of hepatocellular carcinoma: from bench to bedside

Hepatocellular carcinoma (HCC) is a highly heterogeneous malignancy with high incidence, recurrence, and metastasis rates. The emergence of immunotherapy has improved the treatment of advanced HCC, but problems such as drug resistance and immune-related adverse events still exist in clinical practice. The immunosuppressive tumor microenvironment (TME) of HCC restricts the efficacy of immunotherapy and is essential for HCC progression and metastasis. Therefore, it is necessary to elucidate the mechanisms behind immunosuppressive TME to develop and apply immunotherapy. This review systematically summarizes the pathogenesis of HCC, the formation of the highly heterogeneous TME, and the mechanisms by which the immunosuppressive TME accelerates HCC progression and metastasis. We also review the status of HCC immunotherapy and further discuss the existing challenges and potential therapeutic strategies targeting immunosuppressive TME. We hope to inspire optimizing and innovating immunotherapeutic strategies by comprehensively understanding the structure and function of immunosuppressive TME in HCC.

The recruitment of CD8+ T cells through YBX1 stabilization abrogates tumor intrinsic oncogenic role of MIR155HG in lung adenocarcinoma

Previous studies revealed that MIR155HG possessed an oncogenic role in many types of tumors including lung adenocarcinoma (LUAD), along with higher expression in tumors. However, in our study, we observed a positive correlation between MIR155HG expression and overall survival across different cohorts. The transferred PBMC on the NCG mouse model abrogated the tumor intrinsic oncogenic role of MIR155HG in LUAD. Upregulation of MIR155HG positively correlated with CD8+ T cell infiltration both in vitro and in vivo, as well as LUAD tissues. Mechanistically, we revealed that MIR155HG increased the cytokine CCL5 expression at the transcriptional level, which depended on the interaction between MIR155HG and YBX1 protein, a novel transcription factor of CCL5, resulting in the more protein stability of YBX1 through dampening ubiquitination. Additionally, we also observed that MIR155 could increase PD-L1 expression to hamper the activity of recruited CD8+ T cells, which could be rescued through PD-L1 mAb addition. Finally, we uncovered that patients with high MIR155HG expression had a higher response rate to immunotherapy, and the combination of MIR155HG overexpression and PD-L1 mAb increased the efficacy of PD-L1 mAb. Together, our study provides a novel biomarker and potential combination treatment strategy for patients who received immunotherapy.

Dual-Responsive Epigenetic Inhibitor Nanoprodrug Combined with Oncolytic Virus Synergistically Boost Cancer Immunotherapy by Igniting Gasdermin E-Mediated Pyroptosis

Cancer immunotherapy has emerged as a promising approach for the treatment of various cancers. However, the immunosuppressive tumor microenvironment (TME) limits the efficacy of current immunotherapies. In this study, we designed a dual-responsive DNA methyltransferase inhibitor nanoprodrug ACNPs for combination therapy with oncolytic herpes simplex virus (oHSV). We found that the epigenetic inhibitor 5-Azacytidine (5-Aza) upregulated gasdermin E (GSDME) expression at the gene level, whereas the oHSV decreased the ubiquitination and degradation of GSDME to elevate its levels. Based on these observations, we further discovered that ACNPs and oHSV synergistically enhanced GSDME-mediated pyroptosis. Additionally, the combination therapy of ACNPs and oHSV effectively inhibited tumor growth, remodeled the immunosuppressive TME, and improved the efficacy of immune checkpoint blockade (ICB) therapy. These results demonstrate the potential to overcome immunosuppression through synergistic combinations, offering a promising approach for cancer immunotherapy.

Recent Advances in Nanoimmunotherapy by Modulating Tumor-Associated Macrophages for Cancer Therapy

Cancer immunotherapy has yielded remarkable results across a variety of tumor types. Nevertheless, the complex and immunosuppressive microenvironment within solid tumors poses significant challenges to established therapies such as immune checkpoint blockade (ICB) and chimeric antigen receptor T-cell (CAR-T) therapy. Within the milieu, tumor-associated macrophages (TAMs) play a significant role by directly suppressing T-cell functionality and fostering an immunosuppressive environment. Effective regulation of TAMs is, therefore, crucial to enhancing the efficacy of immunotherapies. Various therapeutic strategies targeting TAM modulation have emerged, including blocking TAM recruitment, direct elimination, promoting repolarization toward the M1 phenotype, and enhancing phagocytic capacity against tumor cells. The recently introduced CAR macrophage (CAR-M) therapy opens new possibilities for macrophage-based immunotherapy. Compared with CAR-T, CAR-M may demonstrate superior targeting and infiltration capabilities toward solid tumors. This review predominantly delves into the origin and development process of TAMs, their role in promoting tumor growth, and provides a comprehensive overview of immunotherapies targeting TAMs. It underscores the significance of regulating TAMs in bolstering antitumor therapies while discussing the potential and challenges of developing TAMs as targets for immunotherapy.

Engineered small extracellular vesicle-mediated ferroptosis: A new frontier in cancer immunotherapy

Ferroptosis is a novel iron-dependent form of cell death discovered in recent years, characterized by the accumulation of ferrous iron, the production of reactive oxygen species (ROS) through the Fenton reaction, and lipid peroxidation, ultimately leading to the disruption of the antioxidant system and cell membrane damage. Extensive research has found that ferroptosis plays a significant role in regulating tumor cell immune evasion, tumor development, and remodeling the tumor microenvironment. Small Extracellular vesicles (sEVs), carrying various bioactive molecules (ncRNA, DNA, proteins), are key nanoscale mediators of intercellular communication. Increasing evidence confirms that EVs can regulate the ferroptosis pathway in tumors, promoting tumor cell immune evasion and reshaping the tumor microenvironment. This article aims to comprehensively review the key mechanisms by which sEVs mediate ferroptosis in cancer and provide new insights into targeting tumor immunotherapy.

Targeting CD73 limits tumor progression and enhances anti-tumor activity of anti-PD-1 therapy in intrahepatic cholangiocarcinoma

BACKGROUND & AIMS

Patients with intrahepatic cholangiocarcinoma (iCCA) respond poorly to immune checkpoint blockades (ICBs). In this study, we aimed to dissect the potential mechanisms underlying poor response to ICBs and explore a rational ICB-based combination therapy in iCCA.

METHODS

scRNA-seq dataset GSE151530 was analyzed to investigate the differentially expressed genes in malignant cells following ICBs therapy. RNA-seq analysis and western blot assays were performed to examine the upstream and downstream signaling pathways of CD73. Subcutaneous tumor xenograft models were utilized to investigate the impact of CD73 on iCCA growth. Plasmid AKT/NICD-induced spontaneous murine iCCAs were used to explore the therapeutic efficacy of CD73 enzymatic inhibitor AB680 combined with PD-1 blockade. Time-of-flight mass cytometry (CyTOF) was conducted to identify the tumor-infiltrating immune cell populations and their functional changes in murine iCCAs treated with AB680 in combination with PD-1 antibody.

RESULTS

scRNA-seq analysis identified elevated CD73 expression in malignant cells in response to ICBs therapy. Mechanistically, ICBs therapy upregulated CD73 expression in malignant cells via TNF-α/NF-κB signaling pathway. In vivo studies revealed that CD73 inhibition suppressed the growth of subcutaneous tumors, and achieved synergistic depression effects with gemcitabine and cisplatin (GC). Adenosine produced by CD73 activates AKT/GSK3β/β-catenin signaling axis in iCCA cells. CD73 inhibitor AB680 potentiates anti-tumor efficacy of PD-1 antibody in murine iCCAs. CyTOF analysis showed that AB680 combined with anti-PD-1 therapy promoted the infiltration of CD8+ T, CD4+ T cells, and NK cells in murine iCCAs, while simultaneously decreased the proportions of macrophages and neutrophils. Moreover, AB680 combined with anti-PD-1 significantly upregulated the expression of Granzyme B, Tbet and co-stimulatory molecule ICOS in infiltrating CD8+ T cells.

CONCLUSIONS

CD73 inhibitor AB680 limits tumor progression and potentiates therapeutic efficacy of GC chemotherapy or anti-PD-1 treatment in iCCA. AB680 combined with anti-PD-1 therapy effectively elicits anti-tumor immune response.

Immunotherapy and radiotherapy for older patients with invasive bladder cancer unfit for surgery or chemotherapy: practical proposal by the international geriatric radiotherapy group

The standard of care for non-metastatic muscle invasive bladder cancer is either radical cystectomy or bladder preservation therapy, which consists of maximal transurethral bladder resection of the tumor followed by concurrent chemoradiation with a cisplatin-based regimen. However, for older cancer patients who are too frail for surgical resection or have decreased renal function, radiotherapy alone may offer palliation. Recently, immunotherapy with immune checkpoint inhibitors (ICI) has emerged as a promising treatment when combined with radiotherapy due to the synergy of those two modalities. Transitional carcinoma of the bladder is traditionally a model for immunotherapy with an excellent response to Bacille Calmette-Guerin (BCG) in early disease stages, and with avelumab and atezolizumab for metastatic disease. Thus, we propose an algorithm combining immunotherapy and radiotherapy for older patients with locally advanced muscle-invasive bladder cancer who are not candidates for cisplatin-based chemotherapy and surgery.

"Find Me" and "Eat Me" signals: tools to drive phagocytic processes for modulating antitumor immunity

Phagocytosis, a vital defense mechanism, involves the recognition and elimination of foreign substances by cells. Phagocytes, such as neutrophils and macrophages, rapidly respond to invaders; macrophages are especially important in later stages of the immune response. They detect "find me" signals to locate apoptotic cells and migrate toward them. Apoptotic cells then send "eat me" signals that are recognized by phagocytes via specific receptors. "Find me" and "eat me" signals can be strategically harnessed to modulate antitumor immunity in support of cancer therapy. These signals, such as calreticulin and phosphatidylserine, mediate potent pro-phagocytic effects, thereby promoting the engulfment of dying cells or their remnants by macrophages, neutrophils, and dendritic cells and inducing tumor cell death. This review summarizes the phagocytic "find me" and "eat me" signals, including their concepts, signaling mechanisms, involved ligands, and functions. Furthermore, we delineate the relationships between "find me" and "eat me" signaling molecules and tumors, especially the roles of these molecules in tumor initiation, progression, diagnosis, and patient prognosis. The interplay of these signals with tumor biology is elucidated, and specific approaches to modulate "find me" and "eat me" signals and enhance antitumor immunity are explored. Additionally, novel therapeutic strategies that combine "find me" and "eat me" signals to better bridge innate and adaptive immunity in the treatment of cancer patients are discussed.

The opportunities and challenges of using PD-1/PD-L1 inhibitors for leukemia treatment

Leukemia poses a significant clinical challenge due to its swift onset, rapid progression, and treatment-related complications. Tumor immune evasion, facilitated by immune checkpoints like programmed death receptor 1/programmed death receptor ligand 1 (PD-1/PD-L1), plays a critical role in leukemia pathogenesis and progression. In this review, we summarized the research progress and therapeutic potential of PD-L1 in leukemia, focusing on targeted therapy and immunotherapy. Recent clinical trials have demonstrated promising outcomes with PD-L1 inhibitors, highlighting their role in enhancing treatment efficacy. This review discusses the implications of PD-L1 expression levels on treatment response and long-term survival rates in leukemia patients. Furthermore, we address the challenges and opportunities in immunotherapy, emphasizing the need for personalized approaches and combination therapies to optimize PD-L1 inhibition in leukemia management. Future research prospects include exploring novel treatment strategies and addressing immune-related adverse events to improve clinical outcomes in leukemia. Overall, this review provides valuable insights into the role of PD-L1 in leukemia and its potential as a therapeutic target in the evolving landscape of leukemia treatment.