Combination strategies with PD-1/PD-L1 blockade: current advances and future directions

A mitochondria-interfering nanocomplex cooperates with photodynamic therapy to boost antitumor immunity

Immunotherapeutics against triple-negative breast cancer (TNBC) hold great promise. In this work, we provide a combination therapy for simultaneous increasing tumor immunogenicity and down-regulating programmed cell death ligand 1 (PD-L1) to boost antitumor immunity in TNBC. We prepare bis (diethyldithiocarbamate)-copper/indocyanine green nanoparticles (CuET/ICG NPs) simply in aqueous with one-pot method. CuET/ICG NPs interfere mitochondria, reduce oxygen consumption, and alleviate tumor hypoxia to potentiate photodynamic therapy (PDT) for amplifying immunogenic cell death (ICD). Meanwhile, mitochondria dysfunction leads to energy stress and activates AMPK pathway. As a result, CuET/ICG NPs downregulates membrane PD-L1 (mPD-L1) on both 4T1 cancer cells and cancer stem cells (CSCs) through AMP-activated protein kinase (AMPK)-mediated pathway in hypoxia. Cooperatively, the combinational therapy activates antitumor immunity and triggers long lasting immune memory response to resist tumor re-challenge. Our study represents an attempt that conquers tumor immunosuppressive microenvironment with simple biomedical materials and multimodality treatments.

Parps in immune response: Potential targets for cancer immunotherapy

Immunotherapy in clinical application faces numerous challenges pertaining to both effectiveness and safety. Poly(ADP-ribose) polymerases (PARPs) exhibit multifunctional characteristics by transferring ADP-ribose units to target proteins or nucleic acids. In recent years, more and more attention has been paid to the biological function of PARPs in immune response. This article reviews the relationship between PARP family members and immune response. PARP1 and PARP2 inhibit anti-tumor immune activity by regulating immune checkpoint expression and the cGAS/STING signaling pathway. PARP7 and PARP11 play an important role in promoting immunosuppressive tumor microenvironment. PARP9 promotes the production of Type I interferon and the infiltration of macrophages. PARP13 is a key tumor suppressor that promotes anti-tumor immune response. PARP14 plays a crucial role in promoting the differentiation of macrophages towards the M2 pro-tumor phenotype. Summarizing the molecular mechanisms of PARP7, PARP9, PARP11, PARP13 and PARP14 in regulating immune response is helpful to deepen our comprehension of the role of PARPs in immune function regulation. This provides a reference and basis for targeted PARP-based cancer treatment strategies and drug development. PARP1, PARP7 inhibitors or other PARP inhibitors in combination with immune checkpoint inhibitors or other immunotherapy strategies may be a more effective cancer therapy.

PD‑1/PD‑L1 immune checkpoint in bone and soft tissue tumors (Review)

Anti-programmed cell death 1 (PD-1)/PD-1 ligand-1 (PD-L1) drugs have been used clinically, including those for skin cancer, with reasonable efficacy. Despite extensive ongoing research on bone and soft tissue sarcomas, there is a paucity of reviews that present a coherent picture. The present article is a comprehensive narrative review on the role of the PD-1/PD-L1 immune checkpoint in bone and soft tissue tumors. The review outlines the biological functions and mechanisms of action of PD-1/PD-L1 and its expression and clinical significance in various tumor types, including osteosarcoma and soft tissue sarcoma. Clinical trial results of immune checkpoint inhibitors, their association with prognosis, mechanisms of resistance to therapy, immune-related adverse events, and their potential in combination therapies, were also discussed.

Comparison of Antitumor Effects of Combinations of Immune Checkpoint Inhibitors With Dendritic Cells Intratumorally Injected into Irradiated Mouse Adenocarcinoma

Dendritic cells (DCs) are specialized immune cells that play a crucial role in presenting antigens and activating cytotoxic T lymphocytes to combat tumors. The immune checkpoint receptor programmed cell death-1 (PD-1) can bind to its ligand programmed cell death-ligand 1 (PD-L1), which is expressed on the surface of cancer cells. This interaction suppresses T-cell activation and promotes immune tolerance. Radiation therapy can increase the expression of PD-L1 on tumor cells, which can lead to a decrease in the effectiveness of the treatment, and detailed studies are needed to understand the mechanisms. As many patients develop resistance to chemotherapy and radiotherapy-either through lack of response or cancer recurrence-there is a critical need to maximize synergistic effects by selecting combination treatments that offer improved therapeutic efficacy with minimal side effects. In the present study, immature DCs (iDCs) were introduced directly into irradiated tumor sites (referred as IR/iDCs), and immune checkpoint blockades (ICBs) were administered intraperitoneally. We confirmed the antitumor effect of combining IR/iDCs and ICBs by examining tumor growth and mouse survival. The proportion of CD4 + and CD8 + T cells in splenocytes increased in the IR/iDCs-treated groups. Combining IR/iDCs with an anti-PD-L1 antibody led to a significant reduction in distant tumor growth and improved mouse survival rates compared with IR/iDCs alone or IR/iDCs + anti-PD-1 antibody. These findings suggest that integrating radiotherapy, DC-based immunotherapy, and ICB, specifically targeting PD-L1, may be an effective cancer treatment strategy.

Diagnosis and treatment of lung cancer: A molecular perspective

This editorial comments on the review by Da Silva et al, published in the World Journal of Clinical Oncology which focuses on the molecular perspectives of lung cancer. With the rapid development of molecular technology, new diagnostic methods are constantly emerging, including liquid biopsy, the identification of gene mutations, and the monitoring biomarkers, thus providing precise information with which to identify the occurrence and development of lung cancer. Biomarkers, such as circulating tumor cells, circulating tumor DNA, and circulating RNA can provide helpful information for clinical application. Common types of genetic mutations and immune checkpoints include epidermal growth factor receptor, anaplastic lymphoma kinase, c-ROS proto-oncogene 1, programmed death-1 and cytotoxic T-lymphocyte-associated protein. According to specific biomarkers, targeted therapy and immunotherapy can improve survival outcomes based on the types of gene mutation and immune checkpoints. The application of molecular approaches can facilitate our ability to control the progression of disease and select appropriate therapeutic strategies for patients with lung cancer.

Research progress in bifunctional small molecules for cancer immunotherapy

Immunotherapy has become one of the most revolutionary modalities for cancer treatment with the approval of many anti-PD-L1 (programmed cell death-ligand 1)/PD-1 (programmed cell death-1) monoclonal antibodies (mAbs). However, anti-PD-L1/PD-1 mAbs suffer from several drawbacks including limited clinical efficacy (∼20 %), poor pharmacokinetics, and the development of immune resistance. Hence, the search for PD-1/PD-L1-based combination therapies and other PD-L1-based bifunctional small molecule modulators [e.g. PD-L1/HDAC (Histone Deacetylase), PD-L1/CXCL12 (C-X-C chemokine ligand 12), PD-L1/Tubulin, PD-L1/IDO1 (Indoleamine 2,3 dioxygenase 1), PD-L1/PARP (Poly(ADP-ribose) polymerase), PD-L1/STING (Stimulator of interferon genes), and PD-L1/NAMPT (Nicotinamide phosphoribosyltransferase)-targeting dual inhibitors] has been intensified with considerable strides achieved in the past couple of years. Herein, we summarize the latest development of bifunctional small molecules as immunotherapy for tumor treatment, including those PD-L1-based, A2AR (Adenosine 2A receptor)-based, IDO1-based, Toll-like receptor (TLR)-based, SHP2 (Src homology 2 domain-containing phosphatase 2)-based, and HPK1 (Hematopoietic progenitor kinase 1)-based dual-acting compounds. In addition, we also summarize the tumorigenesis and synergy mechanism of various targets. Finally, the challenges and future directions for bifunctional small molecules for cancer immunotherapy are also discussed in detail.

A disproportionality analysis of real-world events from the FDA Adverse Event Reporting System (FAERS) for Atezolizumab

BACKGROUND

An increasing number of clinical studies have highlighted the use of atezolizumab in tumor immunotherapy. However, There is still a lack of comprehensive research on its associated adverse events (AEs). To improve our understanding of its toxicological profile and to provide valuable clinical insights regarding into the effectiveness of immunotherapy, this study utilized data from the US Food and Drug Administration Adverse Event Reporting System (FAERS) to conduct a retrospective analysis of AEs linked to atezolizumab.

METHODS

We extracted the reports of AEs related to atezolizumab from the FAERS database from the first quarter of 2004 to the first quarter of 2024. We quantified them using the reporting odds ratio (ROR) and proportional reporting ratio (PRR), along with chi-square value (χ²), and conducted systematic classification of the AE signal mining results through SAS 9.4 software.

RESULTS

A total of 19,563 valid reports were incorporated, involving 20 distinct system organ class categories. The AEs related to atezolizumab, reported at the preferred term level, mainly encompassed anemia [ROR 2.33, 95% confidence interval (CI) lower limit 2.09, PRR 2.31, χ² 255.977], febrile neutropenia (ROR 2.81, 95% CI lower limit 2.50, PRR 2.79, χ² 333.586), neutrophil count decreased (ROR 2.14, 95% CI lower limit 1.89, PRR 2.13, χ² 150.688), white blood cell count decreased (ROR 2.35, 95% CI lower limit 2.03, PRR 2.34, χ² 136.673), sepsis (ROR 2.21, 95% CI lower limit 1.91, PRR 2.20, χ² 117.741), alanine aminotransferase increased (ALT) (ROR 2.86, 95% CI lower limit 2.44, PRR 2.85, χ² 180.031), and aspartate aminotransferase increased (AST) (ROR 2.79, 95% CI lower limit 2.38, PRR 2.78, χ² 170.955).

CONCLUSIONS

Apart from various degrees of hepatotoxicity, such as increased ALT and AST, the immune-related hematological toxicity of atezolizumab should also be noted. In clinical practice, healthcare providers should always be vigilant for the occurrence of such medication-related AEs and take measures to enhance the safety of clinical medication use.

Preclinical and first‑in‑human evaluation of [68Ga]Ga-DOTA-PEG2-Asp2-PDL1P PET imaging to assess tumor PD-L1 expression

PURPOSE

PD-L1 PET imaging can provide a non-invasively and real-time assessment of PD-L1 expression status at tumor sites. This study aimed to evaluate the targeting efficacy and biodistribution of a novel peptide-based PD-L1 PET agent, [68Ga]Ga-DOTA-PEG2-Asp2-PDL1P, in preclinical studies and human participants.

METHODS

[68Ga]Ga-DOTA-PEG2-Asp2-PDL1P was synthesized and the probe stability was analyzed in vitro and in vivo. Cellular uptake of the probe was evaluated using tumor cell lines with different PD-L1 expression levels. Small animal PET imaging and semi-quantitative studies were conducted in PC3, H1975 and A549 tumor-bearing mice models, with tumor PD-L1 expression confirmed through immunofluorescence and immunohistochemistry. Furthermore, [68Ga]Ga-DOTA-PEG2-Asp2-PDL1P PET imaging was performed in 1 healthy volunteer and 14 lung cancer patients to assess biodistribution and PD-L1 expression at tumor sites.

RESULTS

[68Ga]Ga-DOTA-PEG2-Asp2-PDL1P exhibited a radiochemical purity of > 99% and had good stability both in vitro and in vivo. In vitro cellular uptake and in vivo small animal PET imaging revealed the probe binding to PD-L1 with high affinity and specificity, consistent with the results of immunofluorescence and immunohistochemistry. In the clinical study involving 15 participants, [68Ga]Ga-DOTA-PEG2-Asp2-PDL1P was proven safe with demonstrating low uptake in normal organs and physiologically excreting via the urinary system. Lung cancer patients with high PD-L1 expression (TPS 70-90%) exhibited higher tumor uptake and tumor-to-background ratios than those with negative or low PD-L1 expression (TPS < 1-10%), with SUVmax of 1.89-2.27 vs. 0.87-1.01, tumor-to-lung ratios of 4.73-7.68 vs. 1.61-2.35, and tumor-to-muscle ratios of 6.73-12.61 vs. 4.35-5.61.

CONCLUSION

[68Ga]Ga-DOTA-PEG2-Asp2-PDL1P showed promising as a PET agent to assess tumor PD-L1 expression in preclinical and first-in-human studies, offering a non-invasive, real-time and accurate tool to address clinical challenges in predicting and assessing the efficacy of immunotherapy.

Peptide-based PET/CT imaging visualizes PD-L1-driven radioresistance in glioblastoma

Radioresistance remains a great challenge for radiotherapy in the treatment of glioblastoma (GBM). PD-L1 expression is a key contributor to radioresistance and immune escape in GBM. The lack of effective methods to monitor the change of PD-L1 during radiotherapy in patients limits timely intervention and management of the resistance. Here, we developed a novel peptide tracer [18F]AlF-NOTA-PCP2 for PET/CT to visualize the changes of PD-L1 expression in response to radiotherapy, revealing PD-L1-driven radioresistance in GBM. The [18F]AlF-NOTA-PCP2 demonstrated high specificity and binding affinity to PD-L1 in vitro. The uptake of [18F]AlF-NOTA-PCP2 on PET/CT showed a strong positive correlation with PD-L1 expression by immunohistochemistry (IHC) (R² = 0.861, P < 0.001) in GBM xenograft tumors. The radiotracer uptake in PD-L1-positive tumors significantly increased post-radiotherapy (21.25 ± 0.91 % vs. 25.12 ± 0.82 %, P = 0.008), aligning with the radioresistance observed in these tumors. In vitro studies revealed that PD-L1-driven radioresistance by enhancing DNA damage repair through upregulation of RAD51 after activation of the PI3K-Akt pathway in cells. Preliminary clinical application in a radiotherapy-treated GBM patient demonstrated the ability to monitor PD-L1 dynamics, supporting its potential for clinical translation. Collectively, this peptide-based small molecule PET/CT radiotracers offer a noninvasive, real-time, and quantitative method to dynamically visualize PD-L1-driven radioresistance in GBM. It could serve as a potential radiotracer for facilitating patient stratification, adjusting radiotherapy regimens, and guiding personalized immunotherapy strategies.

Anti-tumor activity of an αPD-L1-PE38 immunotoxin delivered by engineered Nissle 1917

Although immune checkpoint inhibitors specifically targeting the PD-1/PD-L1 axis have exhibited remarkable clinical success, they are not uniformly effective across all patient cohorts. Immunotoxins, a novel class of cancer therapeutics, offering a promising alternative. PD-L1, which is also present in certain normal tissues, limits its suitability as an ideal target for immunotoxins. The probiotic strain of E. coli Nissle 1917 (EcN) could target and colonize to solid tumors, which positions it as a promising candidate for tumor tissue-specific delivery of anti-tumor proteins. In this study, we constructed a PD-L1-targeted immunotoxin, designated as αPD-L1-PE38, by fusing an anti-PD-L1 nanobody and a clinically validated PE38 toxin. This immunotoxin exhibited potent cytotoxic activity against tumor cells while showed slightly cytotoxic activity against normal cells. To effectively deliver the αPD-L1-PE38 to tumor tissues, we engineered the EcN strain to release the immunotoxin induced by L-arabinose. Upon induction, the immunotoxin was efficiently secreted, and exhibited robust anti-tumor activity mainly by inducing cell apoptosis both in vitro and in vivo. Furthermore, we enhanced the immunotoxin's affinity for PD-L1 by optimizing the linker between the nanobody and PE38 toxin. The engineered EcN expressing the optimized immunotoxin, achieved superior anti-tumor activity. Collectively, our study suggests that the delivery of immunotoxins through live bacteria to improve safety and efficacy is a promising option in cancer therapeutics.

Enhanced effect of radiofrequency ablation on HCC by siRNA-PD-L1-endostatin Co-expression plasmid delivered

Hepatocellular carcinoma (HCC) poses a significant clinical challenge due to high mortality and limited treatment options. Radiofrequency ablation (RFA) is commonly used but can be limited by tumor recurrence. This study explores the potential of combining RFA with an attenuated Salmonella strain carrying siRNA-PD-L1 and endostatin to enhance HCC treatment. In this study, an H22 subcutaneous tumor mouse model was used, with animals divided into five groups for treatment with a blank control, a blank Salmonella plasmid, RFA alone, siRNA-PD-L1-endostatin, or a combination of RFA and siRNA-PD-L1-endostatin. The combination therapy significantly reduced tumor growth, angiogenesis, and PD-L1/VEGF expression in tumor tissues post-RFA. Additionally, it induced tumor cell apoptosis, inhibited proliferation and migration, and increased the infiltration of T lymphocytes, granzyme B+T cells, and CD86+macrophages within tumors. There was also a notable rise in T and NK cell populations in the spleen. In conclusion, combining RFA with siRNA-PD-L1-endostatin delivered by attenuated Salmonella synergistically enhances anti-tumor effects, boosts the anti-tumor immune response, and improves RFA efficacy for HCC.

A Self-Amplifying Photodynamic Biomedicine for Cascade Immune Activation Against Triple-Negative Breast Cancer

The efficacy of immunotherapy in triple-negative breast cancer (TNBC) is significantly hindered by its low immunogenicity and immunosuppressive tumor microenvironment. Non-invasive photodynamic therapy (PDT) is increasingly recognized as a potential immunotherapeutic stimulant in the treatment of TNBC. However, photodynamic immunotherapy is constrained by tumor hypoxia and excessive inflammation suppression during the course of treatment. Herein, a simple and efficacious biomedicine is formulated to overcome adverse influences by amplifying photodynamic immunotherapy, thereby stimulating the systemic immune response. Specifically, the approach targeted tumor delivery by employing specific agents such as the photosensitizer (verteporfin), the hypoxic ameliorator (atovaquone), and the cyclooxygenase-2/prostaglandin E2 (COX-2/PGE2) signaling blocker (celecoxib). More importantly, the biomedicine effectively ameliorated hypoxia and inhibited COX-2/PGE2 signaling, thereby amplifying PDT-induced immunogenic cell death. This, in turn, enhanced the efficacy of photodynamic immunotherapy and triggered a robust immune response cascade. Notably, the self-amplifying photodynamic biomedicine significantly inhibited primary tumors, distal tumors, lung metastases, and post-operative recurrence while maintaining high biocompatibility. To sum up, the work provides a viable cascade stimulation approach and an efficient biomedical nanoplatform, offering a novel strategy for photodynamic immunotherapy of TNBC in the clinic.

Exosome-mediated Crosstalk in the Tumor Immune Microenvironment: Critical Drivers of Hepatocellular Carcinoma Progression

Hepatocellular carcinoma (HCC) is a significant global health issue, ranking as the sixth most prevalent malignancy and the fourth leading cause of cancer-related mortality worldwide. Despite advancements in therapeutic strategies, mortality rates for HCC remain high. The tumor immune microenvironment (TIME) plays a vital role in HCC progression by influencing tumor cell survival and growth. Recent studies highlight the essential role of exosomes in mediating intercellular communication within the TIME, particularly in interactions among tumor cells, immune cells, and fibroblasts. These interactions drive critical aspects of tumor development, including immune escape, angiogenesis, drug resistance, and metastasis. A detailed understanding of the molecular mechanisms by which exosomes modulate the TIME is essential for developing targeted therapies. This review systematically evaluated the roles and regulatory mechanisms of exosomes within the TIME of HCC, examining the impact of both HCC-derived and non-HCC-derived exosomes on various cellular components within the TIME. It emphasized their regulatory effects on cell phenotypes and functions, as well as their roles in HCC progression. The review also explored the potential applications of exosome-based immunotherapies, offering new insights into improving therapeutic strategies for HCC.

Frizzled-7-targeting antibody-derived bifunctional protein retargets NK cells against triple-negative breast cancer cells via MICA-NKG2D axis

BACKGROUND

Hypoxia is associated with the evasion of triple-negative breast cancer (TNBC) from immune surveillance. Hypoxia increases the subpopulation of putative TNBC stem-like cells (TNBCSCs) through activating Wnt/β-Catenin signaling. The shedding of MHC class I-related chain A (MICA) is particularly noteworthy in cancer stem cells (CSCs), promoting the resistance of CSCs to natural killer (NK) cell cytotoxicity. To reestablish MICA/NKG2D-mediated immunosurveillance, we proposed the design of a fusion protein (SHH002-hu1-MICA) which consists of Frizzled-7 (Fzd7)-targeting antibody and MICA, serving as an engager retargeting NK cells against TNBCs, especially TNBCSCs.

METHODS

Opal multicolor immunohistochemistry staining was used to validate the expression of membrane MICA (mMICA) and existence of NK cells in TNBC tumors; flow cytometry (FCM) assay was used to detect the expression of Fzd7/mMICA on TNBCs. Biolayer interferometry (BLI) and surface plasmon resonance (SPR) assays were executed to assess the affinity of SHH002-hu1-MICA towards rhFzd7/rhNKG2D; near-infrared imaging assay was used to evaluate the targeting capability. A cytotoxicity assay was conducted to assess the effects of SHH002-hu1-MICA on NK cell-mediated killing of TNBCs, and FCM assay to analyze the effects of SHH002-hu1-MICA on the degranulation of NK cells. Finally, TNBC cell-line-derived xenografts were established to evaluate the anti-tumor activities of SHH002-hu1-MICA in vivo.

RESULTS

The expression of mMICA is significantly downregulated in hypoxic TNBCs and TNBCSCs, leading to the evasion of immune surveillance exerted by NK cells. The expression of Fzd7 is significantly upregulated in TNBCSCs and exhibits a negative correlation with the expression of mMICA and infiltration level of NK cells. On accurate assembly, SHH002-hu1-MICA shows a strong affinity for rhFzd7/rhNKG2D, specifically targets TNBC tumor tissues, and disrupts Wnt/β-Catenin signaling. SHH002-hu1-MICA significantly enhances the cytotoxicity of NK cells against hypoxic TNBCs and TNBCSCs by inducing the degranulation of NK cells and promotes the infiltration of NK cells in CD44high regions within TNBC xenograft tumors, exhibiting superior anti-tumor activities than SHH002-hu1.

CONCLUSIONS

SHH002-hu1-MICA maintains the targeting property of SHH002-hu1, successfully activates and retargets NK cells against TNBCs, especially TNBCSCs, exhibiting superior antitumor activities than SHH002-hu1. SHH002-hu1-MICA represents a promising new engager for NK cell-based immunotherapy for TNBC.

Targeting novel regulated cell death: disulfidptosis in cancer immunotherapy with immune checkpoint inhibitors

The battle against cancer has evolved over centuries, from the early stages of surgical resection to contemporary treatments including chemotherapy, radiation, targeted therapies, and immunotherapies. Despite significant advances in cancer treatment over recent decades, these therapies remain limited by various challenges. Immune checkpoint inhibitors (ICIs), a cornerstone of tumor immunotherapy, have emerged as one of the most promising advancements in cancer treatment. Although ICIs, such as CTLA-4 and PD-1/PD-L1 inhibitors, have demonstrated clinical efficacy, their therapeutic impact remains suboptimal due to patient-specific variability and tumor immune resistance. Cell death is a fundamental process for maintaining tissue homeostasis and function. Recent research highlights that the combination of induced regulatory cell death (RCD) and ICIs can substantially enhance anti-tumor responses across multiple cancer types. In cells exhibiting high levels of recombinant solute carrier family 7 member 11 (SLC7A11) protein, glucose deprivation triggers a programmed cell death (PCD) pathway characterized by disulfide bond formation and REDOX (reduction-oxidation) reactions, termed "disulfidptosis." Studies suggest that disulfidptosis plays a critical role in the therapeutic efficacy of SLC7A11high cancers. Therefore, to investigate the potential synergy between disulfidptosis and ICIs, this study will explore the mechanisms of both processes in tumor progression, with the goal of enhancing the anti-tumor immune response of ICIs by targeting the intracellular disulfidptosis pathway.

Cancer stem cells and niches: challenges in immunotherapy resistance

Cancer stem cells (CSCs) are central to tumor progression, metastasis, immune evasion, and therapeutic resistance. Characterized by remarkable self-renewal and adaptability, CSCs can transition dynamically between stem-like and differentiated states in response to external stimuli, a process termed "CSC plasticity." This adaptability underpins their resilience to therapies, including immune checkpoint inhibitors and adoptive cell therapies (ACT). Beyond intrinsic properties, CSCs reside in a specialized microenvironment-the CSC niche-which provides immune-privileged protection, sustains their stemness, and fosters immune suppression. This review highlights the critical role of CSCs and their niche in driving immunotherapy resistance, emphasizing the need for integrative approaches to overcome these challenges.

Overview of splicing variation in ovarian cancer

Ovarian cancer remains one of the deadliest gynecological malignancies, with a persistently high mortality rate despite promising advancements in immunotherapy. Aberrant splicing events play a crucial role in cancer heterogeneity and treatment resistance. Many splicing variants, especially those involving key molecular markers such as BRCA1/2, are closely linked to disease progression and treatment outcomes. These variants and related splicing factors hold significant clinical value as diagnostic and prognostic biomarkers and therapeutic targets. This review provides a comprehensive overview of splicing variants in ovarian cancer, emphasizing their role in metastasis and resistance, and offers insights to advance biomarker development and treatment strategies.

ENTPD8 overexpression enhances anti-PD-L1 therapy in hepatocellular carcinoma via miR-214-5p inhibition

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths globally, with poor prognosis due to late diagnosis and limited treatment options. In this study, we evaluated the expression of ectonucleoside triphosphate diphosphohydrolase 8 (ENTPD8) in HCC tissues and its clinical significance. Immunohistochemistry, The Cancer Genome Atlas (TCGA) data, and single-cell expression analysis revealed reduced ENTPD8 levels in liver cancer compared to adjacent tissues, with ENTPD8 primarily expressed in tumor cells within the tumor tissue. In vitro assays demonstrated that ENTPD8 inhibits HCC cell proliferation, invasion, and migration. Mechanistically, ENTPD8 regulates programmed death-ligand 1 (PD-L1) expression through miR-214-5p modulation. In vivo, ENTPD8 overexpression combined with anti-PD-L1 treatment enhanced therapeutic efficacy in HCC mouse models. These findings suggest that ENTPD8 may serve as a prognostic marker and therapeutic target for HCC, offering potential strategies for improving treatment outcomes.

Mendelian randomization analysis revealed a gut microbiota-eye axis in acute anterior uveitis

BACKGROUND

Observational studies suggest that gut microbiome (GM) may contribute to acute anterior uveitis (AAU) development, but causality remains unclear. This study was conducted to test whether specific GM taxa were causally associated with AAU.

METHODS

The GM data were obtained from the DMP, which included 7738 individuals' faecal samples and an analysis of host genotype-taxa abundance associations. The AAU data were derived from the FinnGen Consortium (8624 cases and 473,095 controls). We primarily employed the inverse-variance weighted method, complemented by supplementary sensitivity analyses.

RESULTS

Higher abundance of Lachnospiraceae noname (OR = 0.86, 95% CI 0.81-0.91, P = 5.7 × 10-8), Alistipes finegoldii (OR = 0.87, 95% CI 0.78-0.96, P = 0.008), Erysipelotrichaceae (OR = 0.90, 95% CI 0.81-0.99, P = 0.037), Erysipelotrichia (OR = 0.90, 95% CI 0.81-0.99, P = 0.037), Erysipelotrichales (OR = 0.90, 95% CI 0.81-0.99, P = 0.037), and Bacteroides ovatus (OR = 0.93, 95% CI 0.87-1.00, P = 0.039) predicted a lower AAU risk. Conversely, higher abundance of Bifidobacterium catenulatum (OR = 1.06, 95% CI: 1.02-1.10, P = 0.005), Bacteroides coprocola (OR = 1.11, 95% CI: 1.02-1.21, P = 0.014), Parabacteroides unclassified (OR = 1.12, 95% CI 1.03-1.22, P = 0.010), and Prevotella (OR = 1.15, 95% CI: 1.01-1.29, P = 0.029) predicted a higher AAU risk. The results also showed a reverse causation from AAU to Bifidobacterium catenulatum (OR = 1.39, 95% CI: 1.03-1.86, P = 0.005).

CONCLUSION

This study suggests that specific GM is causally associated with AAU risk, warranting more mechanistic validation and clinical trials.

Discovery of Novel and Highly Potent Dual PD-L1/Histone Deacetylase 6 Inhibitors with Favorable Pharmacokinetics for Cancer Immunotherapy

A series of novel PD-L1/HDAC6 dual inhibitors were designed and synthesized, and compound HP29 was identified as the most potent candidate, which demonstrated excellent and selective HDAC6 inhibitory activity (IC50 = 78 nM, SI > 1282), and high anti-PD-1/PD-L1 activity (IC50 = 26.8 nM). Further studies showed that HP29 could bind with high affinity to PD-L1 and HDAC6 protein. Furthermore, HP29 possessed favorable in vivo pharmacokinetic properties, such as decent oral bioavailability (F = 15.3%). Moreover, HP29 exhibited significant in vivo antitumor efficacy in a melanoma tumor model with a greater tumor growth inhibition (TGI) (65.5%) than that of NP19 (43.2%), ACY-1215 (45.6%), and the combination group (53.9%). Mechanistically, the percentages of tumor-infiltrating lymphocytes (TILs) in the HP29-treated tumor tissues were significantly higher than the combination group or PD-L1 inhibitor monotherapy group, suggesting potential synergistic antitumor immune effects. Collectively, HP29 represents a novel PD-L1/HDAC6 dual inhibitor deserving further investigation as a potential cancer immunomodulating agent.

A Comparative Molecular Dynamics Study of Food-Derived Compounds as PD-L1 Inhibitors: Insights Across Six Flavonoid Subgroups

In this study, we investigated the inhibitory potential of 60 flavonoids from six distinct subgroups on the programmed cell death ligand 1 (PD-L1) dimer through molecular docking and dynamics simulations. Using AutoDock Vina for docking, the binding poses and affinities were evaluated, revealing an average binding affinity of -8.5 kcal/mol for the flavonoids. Among them, ginkgetin exhibited the highest binding free energy of -46.73 kcal/mol, indicating a strong interaction with PD-L1, while diosmin followed closely, with -44.96 kcal/mol. Molecular dynamics simulations were used to further elucidate the dynamic interactions and stability of the flavonoid-PD-L1 complexes, with the analyses showing minimal root mean square deviation (RMSD) and favorable root mean square fluctuation (RMSF) profiles for several compounds, particularly formononetin, idaein, and neohesperidin. Additionally, contact number and hydrogen bond analyses were performed, which highlighted ginkgetin and diosmin as key flavonoids with significant binding interactions, evidenced by their stable conformations and robust molecular interactions throughout the simulations. Ultimately, a cell-based assay confirmed their ability to inhibit the proliferation of cancer cells. These results, validated through cell-based assays, indicate that the strategy of identifying natural compounds with anticancer activity using computational modeling is highly effective.

Spatial interaction mapping of PD-1/PD-L1 in head and neck cancer reveals the role of macrophage-tumour barriers associated with immunotherapy response

BACKGROUND

Mucosal head and neck squamous cell carcinoma (HNSCC) is often diagnosed at an advanced stage, where the prognosis is poor due to the high rates of recurrence and metastasis. With approximately one million new cases projected in 2024, worldwide mortality of HNSCC is estimated to reach 50% of detected cases the same year. Patients with early-stage tumours showed a 50-60% five-year survival rate in the US. Immune checkpoint inhibitors (ICIs) have shown promising results in prolonging survival in a subset of patients with recurrent or metastatic disease. However, challenges remain, particularly the limited efficacy of PD-1/PD-L1 blockade therapies. PD-L1 protein expression has been shown to be limited in its predictive power for ICI therapies. Emerging evidence shows that intricate characterisation of the tumour microenvironment (TME) is fundamental to understand interacting cells. This study aims to bridge the gap in understanding the tumor microenvironment by identifying distinct spatial patterns of PD-1/PD-L1 interactions and their association with immunotherapy responses in head and neck squamous cell carcinoma (HNSCC).

METHODS

In this study, we sought to apply a more nuanced approach to understanding cellular interactions by mapping PD-1/PD-L1 interactions across whole-slide HNSCC tissue samples collected prior to ICI therapy. We used a combination of spatial proteomics (Akoya Biosciences) and an in situ proximity ligation assay (isPLA, Navinci Diagnostics) to visualise PD-1/PD-L1 interactions across cell types and cellular neighbourhoods within the tumour TME.

RESULTS

Our findings indicate the existence of isPLA+ PD-1/PD-L1 interactions between macrophages/CD3 T cell-enriched neighbourhoods and tumour cells at the tumour-stroma boundaries in ICI-resistant tumours. The presence of these dense macrophage-tumour layers, which are either absent or dispersed in responders, indicates a barrier that may restrict immune cell infiltration and promote immune escape mechanisms. In contrast, responders had abundant B and T cell aggregates, predominantly around the tumour edges linked to enhanced immune responses to ICI therapy and better clinical outcomes.

CONCLUSION

This study highlights the utility of isPLA in detecting distinct tumour-immune interactions within the TME, offering new cellular interaction metrics for stratifying and optimising immunotherapy strategies.

Enzyme-Activated Orthogonal Proteolysis Chimeras for Tumor Microenvironment-Responsive Immunomodulation

Precise modulation of dynamic and complex tumor microenvironment (TME) to disrupt tumorigenesis and reshape intratumoral immune infiltration has emerged as promising approaches for enhanced cancer therapy. Among recent innovations, proteolysis-targeting chimeras (PROTACs) represent a burgeoning chemical knockdown technology capable of degrading oncogenic protein homeostasis and inducing dynamic alternations within carcinoma settings, offering potential for antitumor manipulation. However, achieving selectivity in PROTACs that respond to disease environmental stimulation and precisely perturb on-target proteins remains challenging. The multi-step synthesis and limited permeability, attributed to high-molecular-weight and heterobifunctional structures, further hinder their in vivo efficacy. Herein, we present a unique TME-responsive enzyme-activated clickable PROTACs, which features a short peptide-tagged pomalidomide derivative to undergo tumor-specific cleavage by cathepsin protease to induce orthogonal crosslinking of the exposed cysteine with 2-cyanobenzothiazole-labeled epigenetic protein-ligand JQ1, facilitating in situ degrader formation within tumor regions only. Systematic protein profiling and proteomic analysis revealed that such TME-specific clickable-PROTACs not only selectively eliminate epigenetic proteins without tedious pre-synthesis to bridge disparate small-molecule bi-warhead fragments, but also demonstrated superior tumor penetration compared to conventional high-molecular-weight PROTACs. Importantly, these clickable-PROTACs efficiently downregulated immune checkpoint programmed death-ligand 1 (PD-L1) both in vitro and in vivo, remodeling TME for enhanced therapeutics, especially in anti-tumoral immunomodulation.

Profile of STING agonist and inhibitor research: a bibliometric analysis

Background

STING is a core signaling hub molecule in the innate immune system, involved in various diseases, including infectious diseases, autoimmune diseases, tumors, aging, organ fibrosis, and neurodegenerative diseases. Its activation has shown great potential in anti-tumor and anti-infective therapies, with STING agonists emerging as a promising approach in cancer immunotherapy in recent years. This study identifies research trends and potential directions in the field by collecting and analyzing relevant literature.

Methods

A total of 527 publications regarding STING agonists and 107 about inhibitors were retrieved from the WOS Core Collection database. Bibliometric information was extracted with CiteSpace and VOSviewer software for visualization.

Results

It shows that research on both STING agonists and inhibitors is burgeoning rapidly. The United States and China are leading contributors in this field. Application of STING agonists primarily focuses on cancer immunotherapy, while STING inhibitors target inflammation, particularly neuroinflammation and acute lung injury.

Conclusion

Current research emphasizes optimizing STING agonists for permeability, efficacy, and safety, with nanotechnology and lipid nanoparticles being prominent delivery techniques. Future research is expected to focus on drug development and clinical applications. This comprehensive bibliometric analysis provides clinical insights and a guide for further investigation to STING agonist/inhibitor.

Extracellular Vesicle-Based Antitumor Nanomedicines

Extracellular vesicles (EVs) have emerged as promising bioactive carriers for delivering therapeutic agents, including nucleic acids, proteins, and small-molecule drugs, owing to their excellent physicochemical stability and biocompatibility. However, comprehensive reviews on the various types of EV-based nanomedicines for cancer therapy remain scarce. This review explores the potential of EVs as antitumor nanomedicines. Methods for EV extraction, drug loading, and engineering modifications are systematically examined, and the strengths and limitations of these technical approaches are critically assessed. Additionally, key strategies for developing EV-based antitumor therapies are highlighted. Finally, the opportunities and challenges associated with advancing EVs toward clinical translation are discussed. With the integration of multiple disciplines, robust EV-based therapeutic platforms are expected to be manufactured to provide more personalized and effective solutions for oncology patients.

Advancements in the application of ablative therapy and its combination with immunotherapy in anti-cancer therapy

Cancer is a significant health issue impacting humans. Currently, systemic therapies such as chemotherapy have significantly increased the life expectancy of cancer patients. However, some patients are unable to endure systemic treatment due to its significant adverse effects, leading to an increased focus on local therapies including radiation and ablation therapy. Ablation therapy is a precise, low-toxicity, and minimally invasive localized therapy that is increasingly acknowledged by clinicians and cancer patients. Many cancer patients have benefited from it, with some achieving full recovery. Currently, numerous studies have shown that ablation therapy is effective due to its ability to kill cancer cells efficiently and activate the body's anti-cancer immunity. It can also convert "cold cancers" into "hot cancers" and enhance the effectiveness of immunotherapy when used in combination. In this article, we categorize ablation therapy into thermal ablation, cryoablation, photodynamic therapy (PDT), irreversible electroporation (IRE), etc. Thermal ablation is further divided into Radiofrequency ablation (RFA), microwave ablation (WMA), high-frequency focused ultrasound (HIFU), photothermal therapy (PTT), magnetic heat therapy (MHT), etc. We systematically review the most recent advancements in these ablation therapies that are either currently used in clinic or are anticipated to be used in clinic. Then, we also review the latest development of various ablative therapies combined with immunotherapy, and its future development. CLINICAL RELEVANCE STATEMENT: Ablation therapy, an invasive localized treatment, offers an alternative to systemic therapies for cancer patients who cannot tolerate their adverse effects. Its ability to kill cancer cells efficiently and activate anti-cancer immunity. This article reviews recent advancements in ablation therapies, including thermal, cryoablation, PDT, and IRE, and their potential clinical applications, both standalone and in combination with immunotherapy.

Ultrasound nanobubble-based combinational strategies of loaded miR-107-3p and CD133 Ab for anti-PD-L1 and anti-hepatocellular cancer stem cells

BACKGROUND

CD133 is regarded as a marker and target for cancer stem cells (CSCs) in various types of tumors, including hepatocellular carcinoma (HCC). The expressions of CD133 and programmed cell death ligand 1 (PD-L1) in CSCs exhibit a positive feedback regulatory effect. This effect promotes CSC proliferation and immune escape, ultimately leading to tumor progression and poor prognosis.

METHODS

CD133-specific antibodies and miR-107-3p loaded nanobubbles (miR-107-3p/CD133 Ab-NBs) were assembled using various techniques, such as the biotin-avidin system and cationic lipid nanobubbles. The relationship between miR-107-3p and PD-L1 was established via a miR-107-3p mimic/inhibitor using RT-qPCR and Western blot methods. The miR-107-3p/CD133 Ab-NBs were characterized, and their pharmacokinetic attributes were studied in combination with ultrasound-targeted microbubble destruction (UTMD). Subsequently, the anti-tumor efficacy and mechanism were scrutinized both in vitro and in vivo.

RESULTS

miR-107-3p/CD133Ab NBs were successfully prepared through CD133Ab conjugation and miR-107-3p loading, yielding an average particle size of 342.0 ± 26.3 nm, and presenting as spherical particles with uniform size and distribution. By using a mouse subcutaneous transplanted tumor model, paired with UTMD, we found that miR-107-3p/CD133Ab-NBs could significantly accumulate at the tumor site, as observed through the IVIS Spectrum system. These nanoparticles showed considerable anti-tumor activity against HCC, both in vitro and in the xenograft mouse model. Further findings indicated that miR-107-3p/CD133Ab-NBs promoted lymphocyte proliferation enhanced the cytotoxic T lymphocyte (CTL) killing activity, and increased cytokine gene expression. This suggests that the combination of miR-107-3p/CD133Ab-NBs with UTMD could enhance anti-cancer immune responses by inhibiting PD-L1 with miR-107-3p and targeting CD133 on the CSCs of HCC.

CONCLUSIONS

Our study introduces a novel strategy for ultrasound-targeted microbubbles containing miR-107-3p and CD133Ab. This strategy demonstrated substantial anti-tumor activity against HCC by blocking the positive feedback of CD133 and PD-L1 expression in CSCs. Thus, it reveals a potential advantage of combined miR-107-3p/CD133 Ab-NBs therapy for HCC.

A novel therapeutic approach targeting PD-L1 in HNSCC and bone marrow-derived mesenchymal stem cells hampers pro-metastatic features in vitro: perspectives for blocking tumor-stroma communication and signaling

BACKGROUND

Current conventional treatment regimens for head and neck squamous cell carcinoma (HNSCC), are poorly effective because of the emergence of resistance mechanisms. Many studies have reported how the tumor microenvironment influences tumor response to immune checkpoint inhibitors targeting PD-1/PD-L1. It has been reported that overexpression of PD-L1 correlates with and is involved in cancer progression by promoting epithelial-to-mesenchymal-transition (EMT) program, stemness and tumor cell invasiveness through AKT and MAPK pathways. In this study, we investigated how bone marrow mesenchymal stem cells (BM-MSCs) recruited and educated by HNSCC cells are able to promote tumor cell invasion and EMT program. In addition, we analyzed how the crosstalk between stromal cells and tumor cells can affect PD-L1 expression levels. In this context, we developed and characterized a novel anti-PD-L1 recombinant Fab (rFab') and tested its ability to potentiate the effect of cisplatin.

METHODS

BM-MSCs and HNSCC cells co-cultures, cell migration and invasion were performed using Boyden chambers. The effect of treatments on cell viability and growth were analyzed by MTT and clonogenic assay, respectively. The anti-PD-L1 rFab' was prepared in E. Coli and tested for its binding on HNSCC cells and BM-MSCs by FACS analysis and fluorescence microscopy. PD-L1, p-AKT, p-ERK, N-cadherin and β-catenin expression levels were analyzed by western blotting.

RESULTS

BM-MSCs were induced by tumor cells to migrate, invade and to trans-differentiate in cancer associated fibroblasts (CAFs) as demonstrated by increased expression levels of α-SMA and FAP-α. BM-MSCs contributed to HNSCC invasiveness by increasing p-AKT, p-ERK, N-cadherin and β-catenin expression levels. When BM-MSCs and HNSCC cells were co-cultured the level of PD-L1 expression was enhanced in both cells indicating a reciprocal support in favoring tumor aggressiveness. Tumor cell treatment with rFab' anti-PD-L1 reduced their viability, growth, migration and invasion and blunted the underlying signaling pathways. In addition, rFab' anti-PD-L1 was able to potentiate the antitumor effect of cisplatin on HNSCC cells.

CONCLUSIONS

BM-MSCs recruited and educated by HNSCC cells support tumor cell aggressiveness via PD-L1. A novel rFab' anti-PD-L1 reduces HNSCC proliferation, migration and invasion and potentiates the cisplatin effect suggesting its potential to be conjugated with drugs for immuno-cytotoxic therapy.

Gp350-targeted CAR-T therapy in EBV-positive Burkitt lymphoma: pre-clinical development of gp350 CAR-T

BACKGROUND

Epstein-Barr virus (EBV) is an oncovirus belonging to the herpesvirus family, associated with the pathogenesis of multiple malignancies, particularly Burkitt lymphoma (BL). The virus remains latent in host cells and plays a critical role in tumor progression through various mechanisms. A key glycoprotein, gp350, expressed during the lytic phase of EBV, is instrumental in viral entry into B cells and presents a unique antigenic target, making it a promising candidate for immunotherapeutic approaches, such as chimeric antigen receptor T-cell (CAR-T) therapy.

METHODS

In this study, we engineered CAR-T cells targeted against the gp350 glycoprotein and assessed their therapeutic potential through a series of in vitro and in vivo experiments. The efficacy of the gp350-CAR-T cells was evaluated by comparing their cytotoxic effects against both EBV-positive and -negative tumor cell lines. We utilized a xenograft model of Burkitt lymphoma to monitor the impact of gp350-CAR-T cell administration on tumor progression and overall survival.

RESULTS

The engineered gp350-CAR-T cells demonstrated potent cytotoxicity specifically against EBV-positive tumor cell lines. In our in vivo xenograft model, administration of gp350-CAR-T cells resulted in significant inhibition of tumor growth, highlighting their capability to effectively target and eliminate EBV-positive lymphomas. This selectivity underscores the potential of utilizing gp350 as a specific target for immunotherapy.

CONCLUSION

Our findings advocate for the clinical application of gp350-directed CAR-T therapy as a prospective treatment strategy for patients with relapsed or refractory EBV-positive tumors. Given the encouraging preclinical results, further research is warranted to optimize CAR-T cell production processes and extend the potential of this therapy to other EBV-associated malignancies, paving the way for improved outcomes in affected patient populations.

Escherichia coli combination with PD-1 blockade synergistically enhances immunotherapy in glioblastoma multiforme by regulating the immune cells

BACKGROUND

Glioblastoma multiforme (GBM) is the most common and aggressive primary intracranial malignancy. It is characterized by insufficient infiltration of anti-tumor T lymphocytes within the tumor microenvironment (TME), rendering it an "immune cold" disease. This immune deficiency results in poor responses to immune checkpoint blockade (ICB) therapies. Recent studies have demonstrated that bacteria can proliferate within tumors and activate immune responses. Therefore, in this study, we employed Escherichia coli (E. coli) in combination with anti-PD-1 antibodies to treat GBM, with the aim of exploring the immune-activating potential of E. coli in GBM and its synergistic effect on anti-PD-1 therapy.

METHODS

The E. coli and anti-PD-1 antibody therapy were administered intravenously and intraperitoneally, respectively. Complete blood cell count, blood biochemical analysis, hematoxylin and eosin (H&E) staining, and agar plate culture were employed to evaluate the biosafety and tumor-targeting capability of E. coli. ELISA kits were used to detect innate immune cytokines. Flow cytometry and immunofluorescence staining were used to investigate T cells. Tumor volume of tumor-bearing mice was recorded to evaluate the combined treatment efficacy. H&E staining and immunofluorescence staining were used to observe the tumor inhibition markers.

RESULTS

E.coli can specifically target into the tumor region, and activate the innate immune response in mice. Immunofluorescence staining and flow cytometry results demonstrated that the combination treatment group exhibited a significant upregulation of cytotoxic CD8+ T cells and a marked suppression of regulatory T cells compared to the control group. The expression of Ki67 was significantly downregulated, and TUNEL staining revealed an increased number of apoptotic cells in the combination treatment group. Furthermore, the tumor growth rate in the combination treatment group was significantly slower than that in the control group.

CONCLUSIONS

E. coli exhibits potential anti-tumor activity and can activate the innate immune response and further regulate immune cells in the tumor tissues to synergize the effect of anti-PD-1 therapy on GBM, providing new insights to enhance the efficacy of GBM immunotherapy.

Phase Ib study of anti-PD-L1 monoclonal antibody socazolimab in combination with nab-paclitaxel as first-line therapy for advanced urothelial carcinoma

BACKGROUND

PD-1/PD-L1 immune checkpoint inhibitors (ICIs) have demonstrated activity in the post-platinum and platinum-ineligible settings for advanced urothelial carcinoma (aUC). As only around 50% of patients with aUC can tolerate platinum-containing treatment, treatments combining first-line ICIs with non-platinum drugs are urgently needed. Therefore, we assessed the safety and efficacy of the anti-PD-L1 monoclonal antibody Socazolimab in combination with nab-paclitaxel as first-line therapy in aUC (NCT04603846).

METHODS

This was a multi-center, single-arm, phase Ib study that enrolled patients with treatment-naive aUC. Patients received Socazolimab (5 mg/kg) and nab-paclitaxel (260 mg/m2) Q3w. The primary endpoint was safety and tolerability of the combination regimen. Second endpoints were the objective response rate (ORR) and progression-free survival.

RESULTS

Between September, 2020 and September, 2021, 20 patients with urothelial carcinoma were enrolled, arising from renal pelvis (5), bladder (8), and ureter (7). After a median follow-up of 17 months, the median number of treatment cycles was 12. No patients had dose limiting toxicity. All patients had treatment-related adverse events (TRAEs), most of which were grade 1 or 2. The common TRAEs (≥20%) were peripheral neurotoxicity, alopecia, rash, increased ALT, weight loss, weakness, pruritus, increased AST, increased γGT, increased ALP, neutropenia, emesis, and anorexia. Nine patients (45%) developed grade 3 TRAEs including peripheral neurotoxicity (30.0%), increased ALT (10.0%), and increased γGT (5.0%). Two patients (10%) discontinued treatment because of grade 3 mouth ulcer (n = 1) and grade 2 lung fibrosis (n = 1). No grade 4-5 TRAEs were observed. Among the 17 patients who had received at least one tumor assessment, ORR was 58.8% (95% CI, 32.9%-81.6%) and the median progression-free survival was 8.3 months (95% CI, 5.2-19.5). The median duration of response was 13.3 months (95% CI, 2.0-20.1), and the overall survival was 19.5 months (95% CI, 11.2-not reached).

CONCLUSION

Socazolimab combined with nab-paclitaxel has shown good safety and promising antitumor activity as first-line therapy in patients with advanced urothelial carcinoma.

Resetting the Hsc70-mediated lysosomal degradation of PD-L1 via a supramolecular meso peptide for the restoration of acquired anti-tumor T cell immunity

The reduction of cellular PD-L1 abundance through lysosomal degradation is recognized as essential for effective and sustained targeting of PD-L1-dependent immune evasion in cancer. While Hsc70 can interact with PD-L1 to promote its lysosomal degradation, the overexpression of CMTM6 competitively inhibits this interaction, leading to the blockade of PD-L1 lysosomal degradation. To overcome this issue, a meso chimeric peptide PEPPDL1 was designed to specifically bind the PD-1 binding domain of PD-L1 instead of the Hsc70/CMTM6 binding domain, while also binding to Hsc70 to facilitate the dragging of PD-L1 into Hsc70-mediated chaperone-mediated autophagy (CMA), thereby achieving lysosomal degradation. In order to enable internalization into tumor cells, supramolecular engineering techniques were employed through terminal modification involving sulfydryl and monovalent gold ion (Au(I)), both facilitating self-assembly of modified PEPPDL1 into supramolecular nanospheres termed CTAC-PDL1 driven by aurophilic interaction. Furthermore, based on bioinformatics analysis of mRNA expression data from 30 types of tumors obtained from TCGA database, malignant melanoma was identified as the most suitable indication for CTAC-PDL1 due to its specific characteristics of tumor immune. As expected, CTAC-PDL1 effectively reactivated Hsc70-mediated lysosomal degradation of PD-L1 and consequently restored anti-tumor T cell immunity in a B16F10-derived mouse model of malignant melanoma while maintaining a favorable safety profile. Overall, this work not only presents an alternative approach for targeting PD-L1-dependent cancer immune evasion, but also provides a modularized strategy for discovering specific regulators for target proteins in various diseases.

Efficacy and safety of pembrolizumab in patients with advanced endometrial cancer: a systematic review and meta-analysis

Objective

This meta-analysis evaluated pembrolizumab monotherapy and combination therapy's efficacy and safety in recurrent or advanced endometrial cancer (EC).

Methods

We utilized PubMed, Embase, Cochrane Library, and Web of Science databases to identify clinical trials that were used to search literature from July 2013 to July 2023 to evaluate the efficacy and safety of pembrolizumab in patients with advanced EC. Eight studies with 2,742 patients were included. Outcomes were progression-free survival (PFS), overall survival (OS), objective response rate (ORR), complete remission (CR), and adverse events (AEs); a subgroup analysis was carried out based on combination treatment regimens. Quality assessment of the included studies was conducted using the Cochrane Risk of Bias Tool, the Newcastle-Ottawa Scale (NOS), and the Joanna Briggs Institute (JBI) critical appraisal checklist.

Results

Pembrolizumab reduced progression risk [hazard ratio (HR): 0.53; 95% confidence interval (CI): 0.44, 0.63; p < 0.00001] and death risk when combined with lenvatinib (HR: 0.67; 95% CI: 0.59, 0.76; p < 0.00001). Pembrolizumab monotherapy and lenvatinib combination achieved higher ORR (OR: 3.61; 95% CI: 2.12, 6.13; p < 0.00001) and CR rates (OR: 2.7; 95% CI: 1.59, 4.57; p < 0.05) than controls. Single-arm studies: 8% CR and 4% PR in pembrolizumab-treated patients. Pooled AE incidence: 86%, with 43% grade 3/4. Two randomized controlled trials (RCTs) found that the pembrolizumab group had a higher incidence of grade 3 or 4 AEs compared to the control group (OR: 2.23; 95% CI: 1.23, 4.04; p = 0.008).

Conclusion

Pembrolizumab monotherapy or combination significantly improves survival in recurrent or advanced EC and has manageable toxicity albeit with a relatively high incidence of treatment-related AEs.

A subset of neutrophils activates anti-tumor immunity and inhibits non-small-cell lung cancer progression

Neutrophils in the tumor microenvironment (TME) are heterogeneous populations associated with cancer prognosis and immunotherapy. However, the plasticity and function of heterogeneous neutrophils in the TME of non-small-cell lung cancer (NSCLC) remain unclear. Here, we show that neutrophils produce high levels of interleukin (IL)-8, which induce the differentiation of CD74highSiglecFlow neutrophils and suppress the generation of CD74lowSiglecFhigh neutrophils in the TME of IL-8-humanized NSCLC mice. The CD74highSiglecFlow neutrophils boost anti-tumor T cell responses via antigen cross-presentation. Deleting CD74 in IL-8-humanized neutrophils impairs T cell activation and exacerbates NSCLC progression, whereas a CD74 agonist enhances T cell activation and the efficacy of anti-programmed cell death 1 (PD-1) or osimertinib therapies. Additionally, the CD74highCD63low neutrophils in the TME and peripheral blood of advanced NSCLC patients phenocopy the CD74highSiglecFlow neutrophils in the TME of NSCLC mice and correlate well with the responsiveness to anti-PD-1 plus chemotherapies. These findings demonstrate an IL-8-CD74high neutrophil axis that promotes anti-tumor immunity in NSCLC.

Advances in Ultrasound-Targeted Microbubble Destruction (UTMD) for Breast Cancer Therapy

Breast cancer is one of the most common types of cancer in women worldwide and is a leading cause of cancer deaths among women. As a result, various treatments have been developed to combat this disease. Breast cancer treatment varies based on its stage and type of pathology. Among the therapeutic options, ultrasound has been employed to assist in the treatment of breast cancer, including radiation therapy, chemotherapy, targeted immunotherapy, hormonal therapy, and, more recently, radiofrequency ablation for early-stage and inoperable patients. One notable advancement is ultrasound-targeted microbubble destruction (UTMD), which is gradually becoming a highly effective and non-invasive anti-tumor modality. This technique can enhance chemical, genetic, immune, and anti-vascular therapies through its physical and biological effects. Specifically, UTMD improves drug transfer efficiency and destroys tumor neovascularization while reducing toxic side effects on the body during tumor treatment. Given these developments, the application of ultrasound-assisted therapy to breast cancer has gained significant attention from research scholars. In this review, we will discuss the development of various therapeutic modalities for breast cancer and, importantly, highlight the application of ultrasound microbubble-targeted disruption techniques in breast cancer treatment.

Responsive and traceless assembly of iron nanoparticles and 131I labeled radiopharmaceuticals for ferroptosis enhanced radio-immunotherapy

Ferroptosis is an iron-dependent form of programmed cell death with the potential to reverse traditional cancer therapy resistance. The combination of ferroptosis with chemotherapy, photodynamic therapy and X-ray therapy has demonstrated remarkably improved therapeutic efficiency. Radiopharmaceutical therapy (RPT) is an emerging approach that achieves precise radiation to diseased tissues via radionuclide delivery. However, insufficient accumulation and retention of therapeutic radiopharmaceuticals in tumor region as well as cancer radioresistance impact treatment efficacy. Here, a nanoassembly of renal clearable ultrasmall iron nanoparticles (USINPs) and 131I-aPD-L1 is prepared via the affinity of fluorophenylboronic acid modified on the USINPs with 131I-aPD-L1. The 150 nm USINAs(131I-aPD-L1) nanoassembly is stable in blood circulation, effectively targets to the tumor and disassembles in the presence of ATP in the tumor microenvironment. Both in vitro and in vivo experiments prove that USINPs-induced ferroptosis boosted the tumor radiosensitization to 131I while 131I-mediated RPT further enhanced ferroptosis. Meanwhile, the immunogenic cell death caused by RPT and ferroptosis combined with PD-L1 immune checkpoint blockade therapy exhibits a strong antitumor immunity. This study provides a novel way to improve the tumor accumulation of ferroptosis inducer and radiopharmaceuticals, insights into the interaction between RPT and ferroptosis and an effective SPECT-guided ferroptosis-enhanced radio-immunotherapy.

Arming AAV9 with a Single-Chain Fragment Variable Antibody Against PD-1 for Systemic Glioblastoma Therapy

Glioblastoma (GBM) is a highly aggressive brain cancer with a low survival rate, prompting the exploration of novel therapeutic strategies. Immune checkpoint inhibitors have shown promise in cancer treatment but are associated with immune-related toxicities and brain penetration. Here, we present a targeted approach using an adeno-associated virus serotype 9 (AAV9) to systemically deliver a single-chain fragment variable antibody against PD-1 (scFv-PD-1) into the tumor microenvironment (TME). Single-cell RNA sequencing analysis revealed robust PD-1 expression in GBM TME, predominantly on T cells. AAV9-scFv-PD-1 expressed and secreted scFv-PD-1, which effectively binds to PD-1. Systemic administration of AAV9-scFv-PD-1 in an immunocompetent GBM mouse model resulted in a robust cytolytic T-cell activation at the tumor site, marked by accumulation of IFN-γ and Granzyme B, leading to a significant reduction in tumor growth. Importantly, AAV9-scFv-PD-1 treatment conferred a survival benefit, highlighting its therapeutic potential. This study demonstrates the feasibility of systemically delivered AAV9-mediated local expression of scFv-PD-1 for targeted immunotherapy in GBM and warrants further investigation for clinical translation.

PD-1 Inhibitor Aggravate Irradiation-Induced Myocardial Fibrosis by Regulating TGF-β1/Smads Signaling Pathway via GSDMD-Mediated Pyroptosis

Cancer therapy has entered a new era with the use of programmed cell death protein 1 (PD-1) immune checkpoint inhibitors. When combined with thoracic radiotherapy, it demonstrates synergistic anti-tumor effects and potentially worsens radiation-induced myocardial fibrosis (RIMF). RIMF is the final stage of radiation-induced heart disease (RIHD) and a potentially fatal clinical complication of chest radiotherapy. It is characterized by decreased ventricular elasticity and distensibility, which can result in decreased ejection fraction, heart failure, and even sudden cardiac death. Pyroptosis, a type of programmed cell death, is mediated by members of the gasdermin (GSDM) family and has been associated with numerous cardiac disorders. The effect of pyroptosis on myocardial fibrosis caused by a combination of radiotherapy and PD-1 inhibitors remains uncertain. In this study, a 6MV X-ray of 20 Gy for local heart irradiation was used in the RIHD mouse model. We noticed that PD-1 inhibitors aggravated radiation-induced cardiac dysfunction and RIMF, concurrently enhancing the presence of CD8+ T lymphocytes in the cardiac tissue. Additionally, our findings indicated that the combination of PD-1 inhibitor and thoracic radiation can stimulate caspase-1 to cleave GSDMD, thereby regulating pyroptosis and liberating interleukin-8 (IL-18). In the myocardium of mice, the manifestation of pyroptosis mediated by GSDMD is accompanied by the buildup of proteins associated with fibrosis, such as collagen I, transforming growth factor β1 (TGF-β1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and tumor necrosis factor α (TNF-α). Moreover, it was discovered that TFG-β1 induced the phosphorylation of Smad2/Smad3 when the cardiac underwent PD-1 inhibitor in conjunction with thoracic irradiation (IR). The findings of this research indicate that PD-1 inhibitor worsen RIMF in mice by triggering GSDMD-induced pyroptosis and influencing the TGF-β1/Smads pathway. While using the caspase-1 inhibitor Z-YVAD-FMK, RIMF can be alleviated. Blocking GSDMD may be a viable strategy for managing myocardial fibrosis caused by the combination of PD-1 inhibitors and radiotherapy.

Evaluation of Multispecific Drugs Based on Patient-Derived Immunocompetent Tumor Organoids

The evolution of antitumor drug development has transitioned from single-agent chemotherapy to targeted therapy, immunotherapy, and more recently, multispecific drugs. These innovative drugs target multiple cellular or molecular pathways simultaneously, offering a more comprehensive anticancer approach and addressing some of the limitations inherent in traditional monotherapies. However, preclinical assessment of multispecific drugs remains challenging, as conventional tumor models often lack the necessary complexity to accurately reflect the interactions between various cell types and targets. Patient-derived immunocompetent tumor organoids (PDITOs), which incorporate both tumor cells and immune cells, present a promising platform for the evaluation of these drugs. Beyond their use in drug evaluation, PDITOs can also be utilized in personalized drug screening and predicting patient-specific treatment outcomes, thus advancing both multispecific drug development and precision medicine. This perspective discusses the current landscape of multispecific drug development and the methodologies for constructing PDITOs. It also addresses the associated challenges and introduces the concept of employing these organoids to optimize the evaluation and rational design of multispecific drug therapies.

Influence of lactate in resistance to anti‑PD‑1/PD‑L1 therapy: Mechanisms and clinical applications (Review)

Metabolic reprogramming is a prominent characteristic of tumor cells, evidenced by heightened secretion of lactate, which is linked to tumor progression. Furthermore, the accumulation of lactate in the tumor microenvironment (TME) influences immune cell activity, including the activity of macrophages, dendritic cells and T cells, fostering an immunosuppressive milieu. Anti‑programmed cell death protein 1 (PD‑1)/programmed death‑ligand 1 (PD‑L1) therapy is associated with a prolonged survival time of patients with non‑small cell lung cancer. However, some patients still develop resistance to anti‑PD‑1/PD‑L1 therapy. Lactate is associated with resistance to anti‑PD‑1/PD‑L1 therapy. The present review summarizes what is known about lactate metabolism in tumor cells and how it affects immune cell function. In addition, the present review emphasizes the relationship between lactate secretion and immunotherapy resistance. The present review also explores the potential for targeting lactate within the TME to enhance the efficacy of immunotherapy.

Berberine Derivative B68 Promotes Tumor Immune Clearance by Dual-Targeting BMI1 for Senescence Induction and CSN5 for PD-L1 Degradation

Promoting tumor cell senescence arrests the cell cycle of tumor cells and activates the immune system to eliminate these senescent cells, thereby suppressing tumor growth. Nevertheless, PD-L1 positive senescent tumor cells resist immune clearance and possess the ability to secret various cytokines and inflammatory factors that stimulate the growth of tumor cells. Consequently, drugs capable of both triggering senescence in tumor cells and concurrently diminishing the expression of PD-L1 to counteract immune evasion are urgently needed. Here, a berberine derivative B68 is developed, which specifically induces tumor cell senescence by targeting BMI1. B68 also involves the degradation of PD-L1 by targeting CSN5, thereby disrupting the immunosuppressive PD-1/PD-L1 interaction and enabling rapid clearance of senescent tumor cells. This approach simultaneously inhibits tumor progression and activates T cell immunity, as evidenced by the robust antitumor response following B68-induced immunization of senescent cancer cells. Moreover, the synergistic effect of B68 with anti-CTLA4 therapy further enhances antitumor immunity, and its ability to induce senescence in cancer cells triggers a strong protective response by dendritic and CD8+ T cells. These findings provide a scientific basis for developing a new tumor treatment strategy based on senescence induction and lay the foundation for further preclinical research.

AIEgen-self-assembled nanoparticles with anti-PD-L1 antibody functionalization realize enhanced synergistic photodynamic therapy and immunotherapy against malignant melanoma

Immune checkpoint inhibitors (ICIs) become integral in clinical practice, yet their application in cancer therapy is constrained by low overall response rates and the primary resistance of cancers to ICIs. Herein, this study proposes aggregation-induced emission (AIE)-based nanoparticles (NPs) for a more effective and synergistic approach combining immunotherapy and photodynamic therapy (PDT) to achieve higher responses than anti-PD-L1 monotherapy. The TBP@aPD-L1 NPs are constructed by functionalizing azide group-modified TBP-2 (TBP-N3) with anti-PD-L1 antibodies via the DBCO-S-S-PEG2000-COOH linker. The anti-PD-L1 target the tumor cells and promote the TBP-N3 accumulation in tumors for enhanced PDT. Notably, the TBP-N3, featuring aggregation-induced emission, boosts reactive oxygen species (ROS) generation through both type I and type II processes for enhanced PDT. The TBP@aPD-L1-mediated PDT induces more powerful effects of direct tumor cell-killing and further elicits effective immunogenic cell death (ICD), which exerts anti-tumor immunity by activating T cells for ICI treatment and reshapes the tumor immune microenvironment (TIME), thereby enhancing the efficacy of PD-L1 blockade of anti-PD-L1. Consequently, TBP@aPD-L1 NPs demonstrated significantly enhanced inhibition of tumor growth in the mouse model of malignant melanoma (MM). Our NPs act as a facile and effective drug delivery platform for enhanced immunotherapy combined with enhanced PDT in treating MM.

Chimeric Antigen Receptor Cell Therapy: Empowering Treatment Strategies for Solid Tumors

Chimeric antigen receptor-T (CAR-T) cell therapy has demonstrated impressive efficacy in the treatment of blood cancers; however, its effectiveness against solid tumors has been significantly limited. The differences arise from a range of difficulties linked to solid tumors, including an unfriendly tumor microenvironment, variability within the tumors, and barriers to CAR-T cell infiltration and longevity at the tumor location. Research shows that the reasons for the decreased effectiveness of CAR-T cells in treating solid tumors are not well understood, highlighting the ongoing need for strategies to address these challenges. Current strategies frequently incorporate combinatorial therapies designed to boost CAR-T cell functionality and enhance their capacity to effectively target solid tumors. However, these strategies remain in the testing phase and necessitate additional validation to assess their potential benefits. CAR-NK (natural killer), CAR-iNKT (invariant natural killer T), and CAR-M (macrophage) cell therapies are emerging as promising strategies for the treatment of solid tumors. Recent studies highlight the construction and optimization of CAR-NK cells, emphasizing their potential to overcome the unique challenges posed by the solid tumor microenvironment, such as hypoxia and metabolic barriers. This review focuses on CAR cell therapy in the treatment of solid tumors.

Caerin 1.1/1.9-mediated antitumor immunity depends on IFNAR-Stat1 signalling of tumour infiltrating macrophage by autocrine IFNα and is enhanced by CD47 blockade

Previously, we demonstrated that natural host-defence peptide caerin 1.1/caerin 1.9 (F1/F3) increases the efficacy of anti-PD-1 and therapeutic vaccine, in a HPV16 + TC-1 tumour model, but the anti-tumor mechanism of F1/F3 is still unclear. In this study, we explored the impact of F1/F3 on the tumor microenvironment in a transplanted B16 melanoma model, and further investigated the mechanism of action of F1/F3 using monoclonal antibodies to deplete relevant cells, gene knockout mice and flow cytometry. We show that F1/F3 is able to inhibit the growth of melanoma B16 tumour cells both in vitro and in vivo. Depletion of macrophages, blockade of IFNα receptor, and Stat1 inhibition each abolishes F1/F3-mediated antitumor responses. Subsequent analysis reveals that F1/F3 increases the tumour infiltration of inflammatory macrophages, upregulates the level of IFNα receptor, and promotes the secretion of IFNα by macrophages. Interestingly, F1/F3 upregulates CD47 level on tumour cells; and blocking CD47 increases F1/F3-mediated antitumor responses. Furthermore, F1/F3 intratumor injection, CD47 blockade, and therapeutic vaccination significantly increases the survival time of B16 tumour-bearing mice. These results indicate that F1/F3 may be effective to improve the efficacy of ICB and therapeutic vaccine-based immunotherapy for human epithelial cancers and warrants consideration for clinical trials.

Membrane palmitoylated protein MPP1 inhibits immune escape by regulating the USP12/ CCL5 axis in urothelial carcinoma

BACKGROUND

The response rate to immunotherapy in patients with urothelial carcinoma remains limited. Studies have shown that membrane palmitoylated proteins (MPPs) play key roles in tumor progression. However, the mechanisms by which MPP1 regulates immune escape in urothelial carcinoma are not well understood.

METHODS

The TCGA and BEST databases were used to analyze the associations between the expression of members of the MPP family and the prognosis or immunotherapy sensitivity of urothelial carcinoma patients. MPP1 was identified due to its significant association with survival and immunotherapy sensitivity. MPP1 expression in urothelial carcinoma tissues and cell lines was examined. An MPP1 overexpression vector was used to transfect urothelial carcinoma cells. The functional assays included proliferation, migration, urothelial carcinoma cell-CD8+ T-cell coculture, CD8+ T-cell chemotaxis, and tumorigenesis in human immune reconstitution NOG mice (HuNOG). Bioinformatics, coimmunoprecipitation (CO-IP), mass spectrometry, quantitative real-time polymerase chain reaction (RT-qPCR), and western blotting were used to validate the activity of the MPP1/USP12/CCL5 cascade.

RESULTS

Analysis of the BEST data revealed that, compared with other MPP family genes, MPP1 was more strongly associated with urothelial carcinoma prognosis and immunotherapy response. Low MPP1 expression was observed in urothelial carcinoma patients and was positively associated with better survival. MPP1 inhibited the proliferation and migration of urothelial carcinoma cells. Bioinformatics, in vitro coculture assays, and in vivo tumorigenesis experiments demonstrated that MPP1 promotes CCL5 production and CD8+ T-cell chemotaxis in the urothelial carcinoma tumor microenvironment (TME). Mechanistically, bioinformatics, mass spectrometry, co-IP, RT-qPCR, and western blot analyses indicated that MPP1 increases CCL5 expression by binding to and promoting USP12.

CONCLUSIONS

MPP1 significantly inhibits urothelial carcinoma cell proliferation and immune escape via the MPP1/USP12/CCL5 cascade. MPP1 has the potential to serve as a biomarker for guiding immunotherapy in patients with urothelial carcinoma.

Immune checkpoints in B-cell Lymphoma: Still an Unmet challenge from Basic research to clinical practice

In the last decade, advancements in immunotherapy knowledge have highlighted CTLA-4, PD-1, LAG-3, TIM-3, and TIGIT, decisive immune checkpoints exhibiting within the tumor microenvironment (TME), as fundamental objects for cancer immunotherapy. The widespread clinical use of immune checkpoint inhibitors (ICls), employing PD-1/PD-L1 or CTLA-4 antibodies to obstruct crucial checkpoint regulators, is noted in treating B-cell lymphoma patients. Nevertheless, the prolonged advantages of the currently employed treatments against CTLA-4, PD-1, and PD-L1 are uncommon among patients. Thus, recent focus has been progressively moved to additional immune checkpoints on T cells, like LAG-3, TIM-3, and TIGIT, which are now seen as reassuring targets for treatment and broadly acknowledged. There are several types of immunecheckpoint molecules expressed by T cells, and inhibitors targeting immune checkpoints can revive and amplify the immune response of T lymphocytes against tumors, a crucial aspect in lymphoma therapy. However, there is little knowledge about their regulation. Herein, we discuss the anti-tumor effects and functions of ICIs in controlling T-cell activity, as well as the progress in combined application with other immunotherapies.

LBP-CD155 Liposome Nanovaccine Efficiently Resist Colorectal Cancer and Enhance ICB Therapy

Background

Colorectal cancer (CRC) is a highly malignant and aggressive gastrointestinal tumor. Due to its weak immunogenicity and limited immune, cell infiltration lead to ineffective clinical outcomes. Therefore, to improve the current prophylaxis and treatment scheme, offering a favorable strategy efficient against CRC is urgently needed.

Methods

Here, we developed a nanovaccine (LBP-CD155L NVs) loaded with CD155 gene in liposome, which was modified by Lycium barbarum polysaccharides (LBP) through electrostatic interaction. The nanovaccine was characterized by transmission electron microscopy and Zetasizer. It was evaluated in vitro, where NVs facilitated the endocytosis and maturation of DCs, and in vivo, where NVs improved the efficacy of prophylaxis and therapy. In addition, further confirmed the mechanisms by how TLR4 and MGL synergistic pathway endow the nanovaccines towards dendritic cells (DCs). Finally, the safety and tumor immunosuppressive microenvironment were evaluated in the CRC tumor-bearing mouse model.

Results

We successfully developed a nanovaccine that facilitates the endocytosis and maturation of DCs via a synergistic pathway involving TLR4 and MGL, which endow the nanovaccines towards dendritic cells (DCs) and promote the differentiation, thereby enhancing the cytotoxicity of CD8+T cells. Consequently, LBP-CD155L NVs can potentiate the efficacy of prophylactic and therapeutic administration in a mouse CRC model, as evidenced by decreased infiltration of myeloid-derived suppressor cells (MDSCs) and Tregs, reprogrammed the macrophage phenotypes, which promoted polarization from M2-like macrophages to M1-like macrophages, increased infiltration of effector T cells. Prophylactic and therapeutic combination regimens with anti-PD-1 treatment demonstrate synergism that stimulates T-cell infiltration into tumors and counteracts immunosuppression, leading to remarkable tumor remission and enhancing the efficacy of immune checkpoint therapy in solid tumors.

Conclusion

Our work provided that LBP-CD155L NVs may serve as a promising tool for reversing tumor immunosuppressive microenvironment and enhancing ICB therapy in CRC.

NKAP: A new m6A RNA binding protein predicts prognosis and immunotherapy response in head and neck squamous cell carcinoma

OBJECTIVE

This study aimed to investigate whether NKAP (nuclear factor κB activating protein) serves as a prognostic marker and predictive biomarker for immunotherapy response in head and neck squamous cell carcinoma (HNSCC).

METHODS

A retrospective cohort study combined with in vitro analyses was conducted. NKAP mRNA expression levels were assessed in 520 HNSCC tumor tissues and 44 normal tissues from the TCGA dataset and validated in a clinical cohort (n = 32). Clinical correlations with overall survival and immunotherapy outcomes were analyzed. The key pathological variables included tumor stage, grade, HPV status, and TP53 mutation. Appropriate statistics were calculated at a significant level (P<0.05).

RESULTS

In this study, we have collected tissue samples from HNSCC patients (mean age: 52.65 ± 7.76; males 66%, females 34%). NKAP was upregulated in HNSCC tissues compared to adjacent normal tissues (P < 0.001). The high expression of NKAP correlated with advanced tumor stage, grade, and reduced survival (P < 0.05). High expression levels of NKAP were also associated with anti-PD-L1 therapy response (P < 0.05). Functional enrichment analysis revealed NKAP involvement in cell cycle regulation, mRNA processing, and chromatin remodeling pathways critical for cancer progression.

CONCLUSION

NKAP represents a promising prognostic marker and therapeutic target for immunotherapy in HNSCC. Prospective studies are warranted to confirm these findings.

Cellular senescence in tumor immune escape: Mechanisms, implications, and therapeutic potential

Cellular senescence, a hallmark of aging, has emerged as a captivating area of research in tumor immunology with profound implications for cancer prevention and treatment. In the tumor microenvironment, senescent cells exhibit a dual role, simultaneously hindering tumor development through collaboration with immune cells and evading immune cell attacks by upregulating immunoinhibitory proteins. However, the intricate immune escape mechanism of cellular senescence in the tumor microenvironment remains a subject of intense investigation. Chronic inflammation is exacerbated by cellular senescence through the upregulation of pro-inflammatory factors such as interleukin-1β, thereby augmenting the risk of tumorigenesis. Additionally, the interplay between autophagy and cellular senescence adds another layer of complexity. Autophagy, known to slow down the aging process by reducing p53/p21 levels, may be downregulated by cellular senescence. To harness the therapeutic potential of cellular senescence, targeting its immunological aspects has gained significant attention. Strategies such as immune checkpoint inhibitors and T-cell senescence inhibition are being explored in the context of cellular senescence immunotherapy. In this comprehensive review, we provide a compelling overview of the regulation of cellular senescence and delve into the influencing factors, including chronic inflammation, autophagy, and circadian rhythms, associated with senescence in the tumor microenvironment. We specifically focus on unraveling the enigmatic dual role of cellular senescence in tumor immune escape. By deciphering the intricate nature of cellular senescence in the tumor microenvironment, this review aims to advance our understanding and pave the way for leveraging senescence as a promising target for tumor immunotherapy applications.

Comprehensive Analysis Reveals Midnolin as a Potential Prognostic, Therapeutic, and Immunological Cancer Biomarker

Background/Objectives: MIDN (midnolin) is newly discovered method for critically regulating a ubiquitin-independent proteasomal degradation pathway. This study aims to examine the expression, prognostic value, genomic changes, interacting proteins, methylation status, and correlations with the tumor immune microenvironment of MIDN in various cancers. Methods: The GTEx, Depmap, GEPIA2, and Kaplan-Meier Plotter databases are applied to evaluate the MIDN level in tumor and normal tissues and the MIDN prognostic value in cancers. The genetic alterations of MIDN in cancers are investigated using the cBioPortal database. The STRING, GeneMANIA, DAVID, and Human Protein Atlas are harnessed to identify and analyze MIDN-interacted proteins. The Sangerbox 3.0 platform (a pan-cancer analysis module) is used to measure the correlations between the MIDN level and the tumor immune microenvironment, stemness, immune cell infiltration, tumor mutational burden, immune checkpoint genes, and RNA modification genes. Immunofluorescence, qRT-PCR, and Western blotting assays were used to evaluate the biological roles of MIDN in breast and gastric cancer cells. Results: MIDN expression was dysregulated in many cancers and associated with prognosis in several cancers, such as esophageal cancer. MIDN was mutated in 1.7% of cancers, and deep deletion was the dominant mutation type. NR4A1, PSMC1, and EGR1 were selected as MIDN-interacted proteins, and these four molecules were co-expressed in pancreatic cancer, liver cancer, urothelial cancer, melanoma, and breast cancer. MIDN expression was significantly correlated with the infiltration of CD8+ T cell, CD4+ T cell, B cell, macrophage, neutrophil, and DC both in prostate adenocarcinoma and liver hepatocellular carcinoma. The MIDN level was correlated with several immune checkpoint genes, such as VEGFA, and RNA modification genes such as YTHDF1, YTHDF2, YTHDF3, and YTHDC1 in cancers. Furthermore, in breast cancer cells, the downregulation of MIDN suppressed the colony formation abilities and lessened cell-cycle-associated and stemness-associated genes; in gastric cancer, the knockdown of MIDN diminished the mRNA levels of Nanog and LDHA. Strikingly, silence of MIDN upregulated FTO protein expression in both breast and gastric cancer cells. Conclusions: Our findings demonstrate the expression, prognostic value, mutation status, interacting proteins, methylation status, and correlations with the tumor immune microenvironment of MIDN. MIDN will be developed as a potential therapeutic target and a prognosis biomarker.