Disruption of SLFN11 Deficiency-Induced CCL2 Signaling and Macrophage M2 Polarization Potentiates Anti-PD-1 Therapy Efficacy in Hepatocellular Carcinoma

Fusobacterium nucleatum-derived 3-indolepropionic acid promotes colorectal cancer progression via aryl hydrocarbon receptor activation in macrophages

An increasing body of research indicates that Fusobacterium nucleatum (F. nucleatum) significantly influences the onset and progression of colorectal cancer (CRC). Our previous study has shown that F. nucleatum exerts pro-tumorigenic effects through aryl hydrocarbon receptor (AhR) activation. However, the role of its microbial metabolites in regulating immune responses remains unclear. Here, we report for the first time that F. nucleatum-derived 3-Indolepropionic acid (IPA) activates AhR in macrophages, driving M2 polarization and tumor-promoting immunosuppression. We discovered that culture supernatant of F. nucleatum (CSF) robustly activates AhR in macrophages. In co-culture systems, CSF upregulated the expression of the M2 marker CD206 and elevated mRNA levels of CD163, TGF-β, IL-10, and VEGF. In a subcutaneous allograft model, CSF induced an elevated number of CD206+ macrophages and decreased presence of CD8+ T cells within the tumor microenvironment, thereby promoting tumor growth. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed IPA as a novel major AhR-activating metabolite in CSF. Strikingly, IPA recapitulated CSF's effects in promoting tumor cell migration and immunosuppression, both in vitro and in vivo. Critically, the AhR inhibitor CH223191 abolished both IPA-mediated M2 polarization and tumor growth. Our study revealed a novel mechanism by which F. nucleatum-derived IPA reprograms macrophages through AhR activation to fuel CRC progression, providing potential therapeutic targets for CRC treatment and prognosis improvement.

Tumor-Associated Macrophages: Polarization, Immunoregulation, and Immunotherapy

Tumor-associated macrophages' (TAMs) origin, polarization, and dynamic interaction in the tumor microenvironment (TME) influence cancer development. They are essential for homeostasis, monitoring, and immune protection. Cells from bone marrow or embryonic progenitors dynamically polarize into pro- or anti-tumor M2 or M1 phenotypes based on cytokines and metabolic signals. Recent advances in TAM heterogeneity, polarization, characterization, immunological responses, and therapy are described here. The manuscript details TAM functions and their role in resistance to PD-1/PD-L1 blockade. Similarly, TAM-targeted approaches, such as CSF-1R inhibition or PI3Kγ-driven reprogramming, are discussed to address anti-tumor immunity suppression. Furthermore, innovative biomarkers and combination therapy may enhance TAM-centric cancer therapies. It also stresses the relevance of this distinct immune cell in human health and disease, which could impact future research and therapies.

A spreadable self-gelling hemostatic powder sensitizes CAR-NK cell therapy to prevent hepatocellular carcinoma recurrence postresection

Adoptive natural killer cell therapy (ANKCT) harbors great potential for combating postsurgical hepatocellular carcinoma (HCC) recurrence, but its efficacy is limited by tumor microenvironment (TME)-meditated repression on NK cell function and insufficient NK cell homing to tumor sites. Therefore, herein we develop a nanocomposite sprayable self-gelling powder enabling liver-localized codelivery of three FDA-approved drugs including calcitriol (Cal), gemcitabine (Gem), and tazemetostat (Taz) to address these challenges. This powder can be laparoscopically spread to liver wound sites, where it rapidly absorbs interfacial liquid to form a bulk adhesive pressure-resistant hydrogel in situ, implying its application potential in minimally surgery. Moreover, its application to liver resection bed significantly sensitizes allogenic NK and EpCAM chimeric antigen receptor modified-NK-92 (EpCAM-CAR-NK) cell infusion to prevent HCC recurrence in orthotopic Heap1-6 tumor-bearing and patient-derived tumor xenograft (PDX) HCC murine models. Additionally, this powder can allow for an effective hemostatic effect in rat and porcine models due to its powerful tissue adhesion-seal and erythrocyte-aggregating effects. Altogether, our newly developed hemostatic self-gelling powder can significantly sensitize ANKCT to combat HCC recurrence in a manner compatible with surgical treatment of HCC.

Tumor-associated macrophages remodel the suppressive tumor immune microenvironment and targeted therapy for immunotherapy

Despite the significant advances in the development of immune checkpoint inhibitors (ICI), primary and acquired ICI resistance remains the primary impediment to effective cancer immunotherapy. Residing in the tumor microenvironment (TME), tumor-associated macrophages (TAMs) play a pivotal role in tumor progression by regulating diverse signaling pathways. Notably, accumulating evidence has confirmed that TAMs interplay with various cellular components within the TME directly or indirectly to maintain the dynamic balance of the M1/M2 ratio and shape an immunosuppressive TME, consequently conferring immune evasion and immunotherapy tolerance. Detailed investigation of the communication network around TAMs could provide potential molecular targets and optimize ICI therapies. In this review, we systematically summarize the latest advances in understanding the origin and functional plasticity of TAMs, with a focus on the key signaling pathways driving macrophage polarization and the diverse stimuli that regulate this dynamic process. Moreover, we elaborate on the intricate interplay between TAMs and other cellular constituents within the TME, that is driving tumor initiation, progression and immune evasion, exploring novel targets for cancer immunotherapy. We further discuss current challenges and future research directions, emphasizing the need to decode TAM-TME interactions and translate preclinical findings into clinical breakthroughs. In conclusion, while TAM-targeted therapies hold significant promise for enhancing immunotherapy outcomes, addressing key challenges-such as TAM heterogeneity, context-dependent plasticity, and therapeutic resistance-remains critical to achieving optimal clinical efficacy.

FMO2+ cancer-associated fibroblasts sensitize anti-PD-1 therapy in patients with hepatocellular carcinoma

BACKGROUND

The efficacy of immune checkpoint inhibitors (ICIs) for hepatocellular carcinoma (HCC) is limited by heterogeneity in individual responses to therapy. The heterogeneous phenotypes and crucial roles of cancer-associated fibroblasts (CAFs) in immunotherapy resistance remain largely unclear.

METHODS

A specific CAF subset was identified by integrating comprehensive single-cell RNA sequencing, spatial transcriptomics and transcriptome profiling of patients with HCC with different responses to antiprogrammed cell death protein 1 (anti-PD-1) therapy. Mouse orthotopic HCC models and a coculture system were constructed, and cytometry by time-of-flight analysis was performed to investigate the functions and mechanisms of specific CAFs in the immune context of HCC.

RESULTS

We identified a distinct flavin-containing monooxygenase 2 (FMO2)+ CAF subset associated with a favorable response to anti-PD-1 therapy and better clinical outcomes. FMO2+ CAFs increase anti-PD-1 treatment efficacy by promoting tertiary lymphoid structure formation and increasing the infiltration of CD8+ T cells and M1-like macrophages through the C-C motif chemokine ligand 19 (CCL19)-C-C motif chemokine receptor 7 axis. Mechanistically, FMO2 promotes nuclear factor kappa B/p65-mediated CCL19 expression by competitively binding to glycogen synthase 1 (GYS1) with praja ring finger ubiquitin ligase 1 (PJA1), thereby suppressing the PJA1-mediated proteasomal degradation of GYS1. CCL19 treatment potentiated the therapeutic efficacy of anti-PD-1 therapy in mouse orthotopic HCC models. A favorable immunotherapy response was observed in patients with HCC with high serum levels of CCL19.

CONCLUSIONS

We identified a novel FMO2+ CAF subset that serves as a critical regulator of microenvironmental immune properties and a predictive biomarker of the immunotherapy response in patients with HCC. CCL19 in combination with anti-PD-1 therapy may constitute a novel therapeutic strategy for HCC.

Understanding the Dual Role of Macrophages in Tumor Growth and Therapy: A Mechanistic Review

Macrophages are heterogeneous cells that are the mediators of tissue homeostasis. These immune cells originated from monocytes and are classified into two basic categories, M1 and M2 macrophages. M1 macrophages exhibit anti-tumorous inflammatory reactions due to the behavior of phagocytosis. M2 macrophages or tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME) and have a basic role in tumor progression by interacting with other immune cells in TME. By the expression of various cytokines, chemokines, and growth factors, TAMs lead to strengthening tumor cell proliferation, angiogenesis, and suppression of the immune system which further support invasion and metastasis. This review discusses recent and updated mechanisms regarding tumor progression by M2 macrophages. Moreover, the current therapeutic approaches targeting TAMs, their advantages, and limitations are also summarized, and further treatment approaches are outlined along with an elaboration of the tumor regression role of macrophages. This comprehensive review article possibly helps to understand the mechanisms underlying the tumor progression and regression role of macrophages in a comparative way from a basic level to the advanced one.

Harnessing immunotherapy for hepatocellular carcinoma: Principles and emerging promises

HCC is considered as one of the leadin causes of death worldwide, with the ability of resistance towards therapeutics. Immunotherapy, particularly ICIs, have provided siginficant insights towards harnessing the immune system. The present review introduces the concepts and possibilities of immunotherapy for HCC treatment, emphasizing its underlying mechanisms and capacity to enhance patient results, focusing on both pre-clinical and clinical insights. The functions of TME and immune evasion mechanisms typical of HCC would be evaluated along with how contemporary immunotherapeutic approaches are designed to address these challenges. Furthermore, the clinical application of immunotherapy in HCC is discussed, emphasizing recent trial findings demonstrating the effectiveness and safety of drugs. In addition, the problems caused by immune evasion and resistance would be discussed to increase potential of immunotherapy along with combination therapy.

Suprabasin promotes gastric cancer liver metastasis via hepatic stellate cells-mediated EGF/CCL2/JAK2 intercellular signaling pathways

Gastric cancer is among the most prevalent gastrointestinal tumors, with liver metastasis significantly worsening patient outcomes. While hepatic stellate cell activation is crucial in hepatocellular carcinoma progression and liver metastasis, its role in gastric cancer liver metastasis is not well understood. In this study, we identified Suprabasin (SBSN) as a key oncogene driving gastric cancer liver metastasis. SBSN was upregulated in gastric cancer tissues and further elevated in liver metastasis, correlating with poor prognosis. Mechanistically, SBSN promoted proliferation, migration, and invasion of gastric cancer cells by activating the STAT3 signaling pathway, as shown in vitro and in vivo. Using a co-culture model of gastric cancer cells and hepatic stellate cell line LX-2, we found that increased SBSN expression in gastric cancer cells triggered EGF secretion, activating LX-2 cells through the EGF/EGFR axis. Activated LX-2 cells then secreted CCL2, initiating the CCL2/CCR2/JAK2 signaling pathway in gastric cancer cells, facilitating their migration to the liver and promoting colonization and growth. Our findings highlight the prognostic significance of SBSN in gastric cancer and liver metastasis, suggesting it as a potential biomarker for disease progression. The SBSN-mediated EGF/EGFR and CCL2/CCR2/JAK2 signaling axes are critical for LX-2 activation and gastric cancer cell migration, offering a rationale for targeting SBSN in treating gastric cancer liver metastasis.

Clusterin-mediated polarization of M2 macrophages: a mechanism of temozolomide resistance in glioblastoma stem cells

Glioblastoma remains one of the most lethal malignancies, largely due to its resistance to standard chemotherapy such as temozolomide. This study investigates a novel resistance mechanism involving glioblastoma stem cells (GSCs) and the polarization of M2-type macrophages, mediated by the extracellular vesicle (EV)-based transfer of Clusterin. Using 6-week-old male CD34+ humanized huHSC-(M-NSG) mice (NM-NSG-017) and glioblastoma cell lines (T98G and U251), we demonstrated that GSC-derived EVs enriched with Clusterin induce M2 macrophage polarization, thereby enhancing temozolomide resistance in glioblastoma cells. Single-cell and transcriptome sequencing revealed close interactions between GSCs and M2 macrophages, highlighting Clusterin as a key mediator. Our findings indicate that Clusterin-rich EVs from GSCs drive glioblastoma cell proliferation and resistance to temozolomide by modulating macrophage phenotypes. Targeting this pathway could potentially reverse resistance mechanisms, offering a promising therapeutic approach for glioblastoma. This study not only sheds light on a critical pathway underpinning glioblastoma resistance but also lays the groundwork for developing therapies targeting the tumor microenvironment. Our results suggest a paradigm shift in understanding glioblastoma resistance, emphasizing the therapeutic potential of disrupting EV-mediated communication in the tumor microenvironment.

LTA4H improves the tumor microenvironment and prevents HCC progression via targeting the HNRNPA1/LTBP1/TGF-β axis

Leukotriene A4 hydrolase (LTA4H), an inflammatory mediator, has garnered attention for its role in the development of chronic lung diseases and various cancers. Our study highlights the protective role of LTA4H in hepatocellular carcinoma (HCC) occurrence and progression. LTA4H is downregulated in clinical and mouse HCC tumors. LTA4H deficiency exacerbates hepatocyte damage by restraining JNK activation and promotes CD206+ macrophage polarization through the upregulation of LTBP1 expression and downstream transforming growth factor β (TGF-β) secretion and activation. Mechanistically, LTA4H induces heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) phosphorylation, enhancing their interaction and leading to the functional inhibition of HNRNPA1 in regulating Ltbp1 mRNA maturation and processing in the nucleus. LTA4H-deficient patients exhibit poor prognosis and immunotherapy resistance. Combination therapy targeting TGF-β and PD-1 significantly improves the immunotherapy resistance of LTA4H-knockout Hepa1-6 tumors. Our findings reveal the previously unreported role of LTA4H in regulating the tumor microenvironment and provide insights into potential diagnostic and therapeutic strategies for patients with LTA4H-deficient HCC.

MMR deficiency is frequent in colorectal carcinomas with diffuse SLFN11 immunostaining: clinicopathologic and molecular study of 31 cases identified among 3,300 tumors

Schlafen 11 (SLFN11), a regulator of cell fate following DNA injury, sensitizes tumor cells to DNA-damaging agents. Patients with SLFN11-positive tumors may benefit from DNA-damaging chemotherapies. SLFN11 has been studied in different types of cancer including colorectal carcinomas. However, colorectal carcinomas with diffuse positivity (expression in ≥80% of tumor cells) have not been meticulously characterized. SLFN11 immunostaining of tumor microarrays (TMAs) with 3,300 primary CRCs identified 65 (~2.0%) tumors with focal staining (<10% of tumor nuclei positive), 83 (~2.5%) with patchy (≥10% and <80%) and 51 (~1.5%) with diffuse (≥80%) SLFN11 positivity. The latter was confirmed on full sections from donor blocks in 31 (~1%) cases, which were further studied including evaluation of additional immunohistochemical markers, genotyping with targeted DNA sequencing, and assessment of microsatellite instability. SLFN11-positive carcinomas were mostly (21/31, 68%) right-sided tumors with a female predominance (21/31, 68%) and median age of 67 years. Eighteen of 31 (58%) contained areas of mucinous differentiation. Deficiency of mismatch repair proteins was detected in 65% (20/31) of SLFN11-positive carcinomas. Moreover, MLH1 (n = 2), MSH2, MSH6, and PMS2 germline mutations were identified in 25% (5/20) of patients with mismatch repair deficient tumors. BRAF p.V600E mutation was found in 45% (9/20) of mismatch repair deficient, but only 1 of 11 proficient tumors. Colorectal carcinomas with diffuse SLFN11 positivity were often mismatch repair deficient tumors with their typical clinical, morphological, and molecular characteristics.

CCR2 Regulates Referred Somatic Hyperalgesia by Mediating T-Type Ca2+ Channel Currents of Small-Diameter DRG Neurons in Gastric Ulcer Mice

Background: Referred pain frequently co-exists with visceral pain. However, the exact mechanism governing referred somatic hyperalgesia remains elusive. Methods: By injecting 20% acetic acid into the stomach, we established a mouse model of gastric ulcer (GU). Hematoxylin and eosin (H&E) staining was used as the evaluation criterion for the gastric ulcer model. Evan's blue (EB) and von Frey tests detected the somatic sensitized area. The DRG neurons distributed among the spinal segments of the sensitized area were prepared for biochemical and electrophysiological experiments. The CCR2 antagonist was intraperitoneally (i.p.) injected into GU mice to test the effect of blocking CCR2 on somatic neurogenic inflammation. Results: GU not only instigated neurogenic plasma extravasation and referred somatic allodynia in the upper back regions spanning the T9 to T11 segments but also augmented the co-expression of T-type Ca2+ channels and CCR2 and led to the gating properties of T-type Ca2+ channel alteration in T9-T11 small-diameter DRG neurons. Moreover, the administration of the CCR2 antagonist inhibited the T-type Ca2+ channel activation, consequently mitigating neurogenic inflammation and referred somatic hyperalgesia. The application of the CCR2 agonist to normal T9-T11 small-diameter DRG neurons simulates the changes in the gating properties of T-type Ca2+ channel that occur in the GU group. Conclusions: Therefore, these findings indicate that CCR2 may function as a critical regulator in the generation of neurogenic inflammation and mechanical allodynia by modulating the gating properties of the T-type Ca2+ channels.

ACE2 Enhances Sensitivity to PD-L1 Blockade by Inhibiting Macrophage-Induced Immunosuppression and Angiogenesis

Anti-PD-L1-based combination immunotherapy has become the first-line treatment for unresectable hepatocellular carcinoma (HCC). However, the objective response rate is lower than 40%, highlighting the need to identify mechanisms of tolerance to immune checkpoint inhibitors and accurate biomarkers of response. In this study, we used next-generation sequencing to analyze HCC samples from 10 patients receiving anti-PD-L1 therapy. Activation of the renin-angiotensin system was elevated in nonresponders compared with responders, and angiotensin-converting enzyme 2 (ACE2) expression was significantly downregulated in nonresponders. ACE2 deficiency promoted HCC development and anti-PD-L1 resistance, whereas ACE2 overexpression inhibited HCC progression in immune-competent mice. Mass cytometry by time of flight revealed that ACE2-deficient murine orthotopic tumor tissues featured elevated M2-like tumor-associated macrophages, displayed a CCR5+PD-L1+ immunosuppressive phenotype, and exhibited high VEGFα expression. ACE2 downregulated tumor-intrinsic chemokine (C-C motif) ligand 5 expression by suppressing NF-κB signaling through the ACE2/angiotensin-(1-7)/Mas receptor axis. The lower chemokine (C-C motif) ligand 5 levels led to reduced activation of the JAK-STAT3 pathway and suppressed PD-L1 and VEGFα expression in macrophages, blocking macrophage infiltration and M2-like polarization. Pharmacologic targeting of CCR5 using maraviroc enhanced the tumor-suppressive effect of anti-PD-L1 therapy. Together, these findings suggest that activation of the ACE2 axis overcomes the immunosuppressive microenvironment of HCC and may serve as an immunotherapeutic target and predictive biomarker of response to PD-L1 blockade. Significance: ACE2 regulates the immune landscape of hepatocellular carcinoma by abrogating M2-like macrophage polarization and sensitizes tumors to anti-PD-L1, suggesting that harnessing the ACE2 axis could be a promising strategy to improve immunotherapy efficacy.

Spatial heterogeneity of the hepatocellular carcinoma microenvironment determines the efficacy of immunotherapy

Hepatocellular carcinoma (HCC) remains a global health challenge owing to its widespread incidence and high mortality. HCC has a specific immune tolerance function because of its unique physiological structure, which limits the efficacy of chemotherapy, radiotherapy, and molecular targeting. In recent years, new immune approaches, including adoptive cell therapy, tumor vaccines, and oncolytic virus therapy, have shown great potential. As the efficacy of immunotherapy mainly depends on the spatial heterogeneity of the tumor immune microenvironment, it is necessary to elucidate the crosstalk between the composition of the liver cancer immune environment, from which potential therapeutic targets can be selected to provide more appropriate individualized treatment programs. The role of spatial heterogeneity of immune cells in the microenvironment of HCC in the progression and influence of immunotherapy on improving the treatment and prognosis of HCC were comprehensively analyzed, providing new inspiration for the subsequent clinical treatment of liver cancer.

Disruption of tumor-intrinsic PGAM5 increases anti-PD-1 efficacy through the CCL2 signaling pathway

BACKGROUND

Immunosuppressive phenotype compromised immunotherapy efficacy of hepatocellular carcinoma. Tumor cells intrinsic mitochondria dynamics could pass effects on the extracellular microenvironment through mtDNA stress. PGAM5 anchors at mitochondria and regulates mitochondria functions. We aim to explore whether the regulation of tumor-intrinsic PGAM5 on mitochondria affects tumor-infiltrating immune cells in the microenvironment and whether tumor-intrinsic PGAM5 can be a therapeutic target to enhance the immunotherapy efficacy of hepatocellular carcinoma (HCC).

METHODS

We analyzed the correlation of PGAM5 expression and immune cells infiltration using Gene Expression Omnibus (GEO) and The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA-LIHC) data sets based on cibersort algorithm and tumor-tissue arrays from two independent cohorts. To further validate our findings, we established subcutaneous and orthotopic mouse HCC models with tumor-intrinsic Pgam5 deficiency and analyzed tumor-infiltrating immune cells by flow cytometry and single-cell RNA sequencing. Mechanistically, we established an in vitro co-culture system and analyzed proteomics data to find out the bridge between tumor cell PGAM5 and tumor-associated macrophages (TAMs) in the microenvironment. Immunofluorescence, chromatin-immunoprecipitation, ELISA, mass spectrometry were conducted to explore the molecular pathway. Macrophages were depleted to investigate whether the effects of tumor-intrinsic PGAM5 on TAMs could affect immunotherapy efficacy in HCC orthotopic and subcutaneous mouse models.

RESULTS

PGAM5 expression in tumor was positively correlated with M2-phenotype TAM infiltration in patients with both HCC and mouse HCC tumor models. High tumor-intrinsic PGAM5 expression promoting M2 TAMs infiltration correlated with poor clinical-pathological characteristics and prognosis in patients with HCC. Disruption of tumor-intrinsic Pgam5 reduced TAM M2 polarization and inhibited HCC tumor growth in tumor-bearing mice. Mechanistically, in HCC cells PGAM5 deficiency inhibited mitochondria fission by promoting TRIM28 binding with DRP1, which increased ubiquitination and degradation of DRP1. Tumor-intrinsic PGAM5 deficiency mediated mitochondria fusion and reduced cytosolic mtDNA stress which attenuated TLR9 activation and downstream NF-κB-regulated CCL2 secretion. Furthermore, disruption of tumor-intrinsic Pgam5 significantly facilitated CD8+ T cells activation and improved anti-programmed cell death protein-1 therapeutic efficacy with macrophages depletion compromising synergistic antitumor immune response.

CONCLUSION

Our results shed light on the effect of tumor mitochondria dynamics on TAMs in tumor microenvironment. Tumor-intrinsic PGAM5 can be a therapeutic target to improve immunotherapy efficacy in patients with HCC.

Ginsenoside RK3 inhibits glioblastoma by modulating macrophage M2 polarization via the PPARG/CCL2 axis

BACKGROUND

Glioblastoma is recognized as the most aggressive form of intracranial tumor, presenting significant challenges in treatment. Recent emphasis has been placed on the potential of traditional Chinese medicine (TCM) as an adjuvant treatment for cancer.

METHODS

We employed a series of assays-including CCK8, EdU, Transwell, and neurosphere formation-to evaluate the impact of ginsenoside RK3 on the phenotype of GBM. The modulation of macrophage M2 polarization by ginsenoside RK3 was assessed through flow cytometry, immunohistochemistry, and Western blot analysis. Furthermore, we utilized sequencing analysis and network pharmacology to identify potential therapeutic targets.

RESULTS

Our findings reveal that ginsenoside RK3 not only inhibits the phenotype of glioblastoma cells but also suppresses tumor progression in vivo while attenuating macrophage M2 polarization within the tumor immune microenvironment. Notably, ginsenoside RK3 down-regulates PPARG expression in tumor cells, leading to decreased secretion of CCL2, which subsequently diminishes macrophage M2 polarization. Additionally, we demonstrated that combining ginsenoside RK3 with temozolomide significantly enhances the inhibition of glioblastoma's malignant characteristics and progression.

CONCLUSIONS

This study innovatively highlights the dual mechanism of ginsenoside RK3 in glioblastoma treatment: it impedes tumor progression by modulating the PPARG/CCL2 pathway and enhances the efficacy of temozolomide. Our research underscores the promising role of herbal medicine in the management of glioblastoma, paving the way for novel therapeutic strategies that integrate traditional approaches with conventional treatments.

Engineering mesoporous polydopamine-based potentiate STING pathway activation for advanced anti-biofilm therapy

The biofilm-induced "relatively immune-compromised zone" creates an immunosuppressive microenvironment that is a significant contributor to refractory infections in orthopedic endophytes. Consequently, the manipulation of immune cells to co-inhibit or co-activate signaling represents a crucial strategy for the management of biofilm. This study reports the incorporation of Mn2+ into mesoporous dopamine nanoparticles (Mnp) containing the stimulator of interferon genes (STING) pathway activator cGAMP (Mncp), and outer wrapping by M1-like macrophage cell membrane (m-Mncp). The cell membrane enhances the material's targeting ability for biofilm, allowing it to accumulate locally at the infectious focus. Furthermore, m-Mncp mechanically disrupts the biofilm through photothermal therapy and induces antigen exposure through photodynamic therapy-generated reactive oxygen species (ROS). Importantly, the modulation of immunosuppression and immune activation results in the augmentation of antigen-presenting cells (APCs) and the commencement of antigen presentation, thereby inducing biofilm-specific humoral immunity and memory responses. Additionally, this approach effectively suppresses the activation of myeloid-derived suppressor cells (MDSCs) while simultaneously boosting the activity of T cells. Our study showcases the efficacy of utilizing m-Mncp immunotherapy in conjunction with photothermal and photodynamic therapy to effectively mitigate residual and recurrent infections following the extraction of infected implants. As such, this research presents a viable alternative to traditional antibiotic treatments for biofilm that are challenging to manage.

Schlafen 11 Expression in Patients With Small Cell Lung Cancer and Its Association With Clinical Outcomes

BACKGROUND

Schlafen 11 (SLFN-11) has been identified as a sensitizer of tumor cells to DNA-damaging agents. However, the relationship between SLFN-11 expression and clinical outcomes in patients with small cell lung cancer (SCLC) remains unexplored. Thus, we aimed to evaluate the impact of SLFN-11 expression on survival in patients with limited-stage (LS) SCLC.

METHODS

We conducted a retrospective review of data from patients pathologically diagnosed with LS-SCLC post-surgery between January 2008 and December 2018. SLFN-11 expression was assessed using immunohistochemistry in tissue microarrays and scored using a histology (H)-score (range: 0-300).

RESULTS

Overall, 86 patients were included in the analysis with a median H-score of 43 for SLFN-11 expression. Among the patients, 44 had high SLFN-11 expression (provisionally defined as H-score ≥ 43). No significant differences in clinical profiles were observed between the two groups (high and low SLFN expression). The median survival durations were not reached (NR; 95% confidence interval [CI]: 65.1 months to NR) and 33.5 months (95% CI: 24.2 months to NR) for patients with high and low SLFN-11 expression, respectively (hazard ratio [HR]: 0.40, 95% CI: 0.19-0.81; p = 0.012). Among patients who relapsed post-surgery (n = 21), the median survival durations were 22.0 (95% CI: 7.6-44.9 months) and 8.1 (95% CI: 1.8-24.6 months) months in patients with high and low SLFN-11 expression, respectively (HR: 0.22, 95% CI: 0.06-0.84; p = 0.026).

CONCLUSIONS

High SLFN-11 expression is associated with relatively longer survival in patients with LS-SCLC in both those undergoing surgery and those who have relapsed.

The heterogeneity of cellular metabolism in the tumour microenvironment of hepatocellular carcinoma with portal vein tumour thrombus

Given the growing interest in the metabolic heterogeneity of hepatocellular carcinoma (HCC) and portal vein tumour thrombus (PVTT). This study comprehensively analysed the metabolic heterogeneity of HCC, PVTT, and normal liver samples using multi-omics combinations. A single-cell RNA sequencing dataset encompassing six major cell types was obtained for integrated analysis. The optimal subtypes were identified using cluster stratification and validated using spatial transcriptomics and fluorescent multiplex immunohistochemistry. Then, a combined index based meta-cluster was calculated to verify its prognostic significance using multi-omics data from public cohorts. Our study first depicted the metabolic heterogeneity landscape of non-malignant cells in HCC and PVTT at multiomics levels. The optimal subtypes interpret the metabolic characteristics of PVTT formation and development. The combined index provided effective predictions of prognosis and immunotherapy responses. Patients with a higher combined index had a relatively poor prognosis (p <0.001). We also found metabolism of polyamines was a key metabolic pathway involved in conversion of metabolic heterogeneity in HCC and PVTT, and identified ODC1 was significantly higher expressed in PVTT compared to normal tissue (p =0.03). Our findings revealed both consistency and heterogeneity in the metabolism of non-malignant cells in HCC and PVTT. The risk stratification based on cancer-associated fibroblasts and myeloid cells conduce to predict prognosis and guide treatment. This offers new directions for understanding disease development and immunotherapy responses.

Notch signaling in digestive system cancers: Roles and therapeutic prospects

Digestive system cancers rank among the most prevalent malignant tumors, maintaining persistently high incidence and mortality rates. Notch signaling activity, often aberrant in esophageal, gastric, hepatic, pancreatic, and colorectal cancers, plays a pivotal role in the initiation, progression, and therapy resistance of these malignancies. As a highly conserved pathway, Notch signaling is integral to cell differentiation, survival, proliferation, stem cell renewal, development, and morphogenesis. Its dysregulation has been increasingly linked to various diseases, particularly digestive system cancers. In these malignancies, altered Notch signaling influences multiple biological processes, including cell proliferation, invasion, cell cycle progression, immune evasion, drug resistance, and stemness maintenance. Understanding the mechanisms of Notch signaling in digestive system cancers is essential for the development of novel targeted therapies. Numerous Notch pathway-targeting drugs are currently in preclinical studies, demonstrating promising efficacy both as monotherapies and in combination with conventional anti-cancer treatments. This review summarizes recent high-quality findings on the involvement of Notch signaling in digestive system cancers, focusing on the expression changes and pathological mechanisms of its dysregulated components. Special emphasis is placed on the potential of translating Notch-targeted approaches into therapeutic strategies, which hold promise for overcoming the limitations of existing treatments and improving the poor prognosis associated with these cancers.

Identification of ETV5 as a prognostic marker related to epigenetic modification in pan-cancer and facilitates tumor progression in hepatocellular carcinoma

ETS variant transcription factor 5 (ETV5), a master transcription factor during development, exerts vital function on the occurrence and progression of various cancers. In order to systematically analyze and explore ETV5 potential specific regulatory mechanisms in pan-cancer, RNA sequencing data and clinicopathological features of patients with various tumors were obtained through the Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases, and an integrated data mining analysis was carried out, including the association of ETV5 expression with patient prognosis, drug sensitivity and epigenetic modification. The results revealed that abnormally highly expressed ETV5 resulted in unfavorable prognosis and differential drug sensitivity in multiple malignancies, and its expression was associated with epigenetic modification modulators including EZH2. ETV5 related genes were enriched in tumorigenesis biological processes and signaling pathways. In hepatocellular carcinoma, ETV5 expression was correlated with patients' tumor pathological stage and resulted in adverse outcome of patients. Our further experiments evidences indicated that ETV5 facilitated cell proliferation and reduced sensitivity to GSK126 via regulating EZH2. Collectively, this study comprehensively elucidates the carcinogenic effects and molecular mechanisms of ETV5 in tumorigenesis and development, and provides theoretical basis and guidance for tumor diagnosis, targeted therapy for ETV5 and clinical epigenetic drug research.

GPER1 signaling restricts macrophage proliferation and accumulation in human hepatocellular carcinoma

Background

Sex hormones and their related receptors have been reported to impact the development and progression of tumors. However, their influence on the composition and function of the tumor microenvironment is not well understood. We aimed to investigate the influence of sex disparities on the proliferation and accumulation of macrophages, one of the major components of the tumor microenvironment, in hepatocellular carcinoma (HCC).

Methods

Immunohistochemistry was applied to assess the density of immune cells in HCC tissues. The role of sex hormone related signaling in macrophage proliferation was determined by immunofluorescence and flow cytometry. The underlying regulatory mechanisms were examined with both in vitro experiments and murine HCC models.

Results

We found higher levels of macrophage proliferation and density in tumor tissues from male patients compared to females. The expression of G protein-coupled estrogen receptor 1 (GPER1), a non-classical estrogen receptor, was significantly decreased in proliferating macrophages, and was inversely correlated with macrophage proliferation in HCC tumors. Activation of GPER1 signaling with a selective agonist G-1 suppressed macrophage proliferation by downregulating the MEK/ERK pathway. Additionally, G-1 treatment reduced PD-L1 expression on macrophages and delayed tumor growth in mice. Moreover, patients with a higher percentage of GPER1+ macrophages exhibited longer overall survival and recurrence-free survival compared to those with a lower level.

Conclusions

These findings reveal a novel role of GPER1 signaling in regulating macrophage proliferation and function in HCC tumors and may offer a potential strategy for designing therapies based on understanding sex-related disparities of patients.

WWOX tuning of oleic acid signaling orchestrates immunosuppressive macrophage polarization and sensitizes hepatocellular carcinoma to immunotherapy

BACKGROUND

Immune checkpoint inhibitors (ICIs) are therapeutically effective for hepatocellular carcinoma (HCC) but are individually selective. This study examined the role of specific common fragile sites (CFSs) related gene in HCC immunotherapy.

METHODS

We analyzed HCC tissues using next-generation sequencing and flow cytometry via time-of-flight technology. A humanized orthotopic HCC mouse model, an in vitro co-culture system, untargeted metabolomics and a DNA pulldown assay were used to examine the function and mechanism of WWOX in the tumor immune response.

RESULTS

WWOX was the most upregulated CFS-related gene in HCC patients responsive to ICIs. WWOX deficiency renders HCC resistant to PD-1 treatment in humanized orthotopic HCC mouse model. Macrophage infiltration is increased and CD8 T-cell subset infiltration is decreased in WWOX-deficient HCC patients. HCC-derived oleic acid (OA) promotes macrophage conversion to an immunosuppressive phenotype. Mechanistically, WWOX deficiency promoted OA synthesis primarily via competitive binding of NME2 with KAT1, which promoted acetylation of NME2 at site 31 and inhibited NME2 binding to the SCD5 promoter region. Pharmacological blockade of SCD5 enhanced the antitumor effects of anti-PD-1 therapy.

CONCLUSIONS

WWOX is a key factor for immune escape in HCC patients, which suggests its use as a biomarker for stratified treatment with ICIs in clinical HCC patients.

Research progress of the SLFN family in malignant tumors

The Schlafen (SLFN) gene family has emerged as a critical subject of study in recent years, given its involvement in an array of cellular functions such as proliferation, differentiation, immune responses, viral infection inhibition, and DNA replication. Additionally, SLFN genes are linked to chemosensitivity, playing a pivotal role in treating malignant tumors. Human SLFNs comprise three domains: the N-terminal, middle (M), and C-terminal. The N- and C-terminal domains demonstrate nuclease and helicase/ATPase activities, respectively. Meanwhile, the M-domain likely functions as a linker that connects the enzymatic domains of the N- and C-terminals and may engage in interactions with other proteins. This paper aims to present a comprehensive overview of the SLFN family's structure and sequence, examine its significance in various tumors, and explore its connection with immune infiltrating cells and immune checkpoints. The objective is to assess the potential of SLFNs as vital targets in cancer therapy and propose novel strategies for combined treatment approaches.

IDO1 inhibitors are synergistic with CXCL10 agonists in inhibiting colon cancer growth

Indoleamine 2,3-dioxygenase 1 (IDO1) is an immune checkpoint that degrades L-tryptophan to kynurenine (Kyn) and enhance immunosuppression, which can be an attractive target for treating colon cancer. IDO1 inhibitors have limited efficacy when used as monotherapies, and their combination approach has been shown to provide synergistic benefits. Many studies have shown that targeting chemokines can promote the efficacy of immune checkpoint inhibitors. Therefore, this study explored the use of IDO1 inhibitors with multiple chemokines to develop a new combination regimen for IDO1 inhibitors. We found that IDO1 inhibitors reduce the secretion of C-X-C motif ligand 10(CXCL10) in cancer cells, and CXCL10 supplementation significantly improved the anticancer effect of IDO1 inhibitors. The combination of the IDO1 inhibitor with CXCL10 or its agonist axitinib had a synergistic inhibitory effect on the growth of colon cancer cells and transplanted CT26 tumors. This synergistic effect may be achieved by inhibiting cancer cell proliferation, promoting cancer cell apoptosis, promoting CD8+T cell differentiation and decreasing Tregs. Two downstream pathways of IDO1 affect CXCL10 secretion. One being the Kyn-aryl hydrocarbon receptor (AHR) pathway, the other is the general control nonderepressible 2(GCN2). Our study provides a new reference for combination regimens of IDO1 inhibitors.

Spatial analysis reveals targetable macrophage-mediated mechanisms of immune evasion in hepatocellular carcinoma minimal residual disease

Hepatocellular carcinoma (HCC) frequently recurs from minimal residual disease (MRD), which persists after therapy. Here, we identified mechanisms of persistence of residual tumor cells using post-chemoembolization human HCC (n = 108 patients, 1.07 million cells) and a transgenic mouse model of MRD. Through single-cell high-plex cytometric imaging, we identified a spatial neighborhood within which PD-L1 + M2-like macrophages interact with stem-like tumor cells, correlating with CD8+ T cell exhaustion and poor survival. Further, through spatial transcriptomics of residual HCC, we showed that macrophage-derived TGFβ1 mediates the persistence of stem-like tumor cells. Last, we demonstrate that combined blockade of Pdl1 and Tgfβ excluded immunosuppressive macrophages, recruited activated CD8+ T cells and eliminated residual stem-like tumor cells in two mouse models: a transgenic model of MRD and a syngeneic orthotopic model of doxorubicin-resistant HCC. Thus, our spatial analyses reveal that PD-L1+ macrophages sustain MRD by activating the TGFβ pathway in stem-like cancer cells and targeting this interaction may prevent HCC recurrence from MRD.

Polarization of Macrophages in Tumor Microenvironment Using High-Throughput Single-Cell Metabolomics

Macrophages consist of a heterogeneous population of functionally distinct cells that participate in many physiological and pathological processes. They exhibit prominent plasticity by changing their different functional phenotypes represented by proinflammatory (M1) and anti-inflammatory (M2) in response to different environmental stimuli. Emerging evidence illustrates the importance of intracellular metabolic pathways in macrophage polarizations and functions. In the tumor microenvironment (TME), macrophages tend to M2 polarization, which promotes tumor growth and leads to adverse physiological effects. Due to the lack of highly specific antigens in M1 and M2 macrophages, significant challenges present in isolating these subtypes from clinical samples or in vitro coculture models of tumor-immune cells. In reverse, the single-cell technique provides the possibility to investigate the factors influencing macrophage polarization in the TME. In this research, we employed inertial microfluidic chip-mass spectrometry (IMC-MS) to conduct single-cell metabolomics analysis of macrophages polarized into the two major phenotypes, respectively, and 213 metabolites were identified in total. Subsequently, differential metabolites between macrophage phenotypes were analyzed using volcano plots and binary logistic regression models. Glutamine was pinpointed as a key metabolite for the M1 and M2 phenotypes. Experimental results from both monoculture and coculture cell models demonstrated that M1 polarization is more reliant on the presence of glutamine in the culture environment than M2 polarization. Glutamine deficiency resulted in failed M1 polarization, while its absence had a less pronounced effect on M2 polarization. Replenishing an appropriate amount of glutamine during the intermediate stages of coculture models significantly enhanced the proportion of M1 polarization and suppressed the growth of tumor cells. This research elucidated glutamine as a key factor influencing macrophage polarization in the TME via single-cell metabolomics based on IMC-MS, offering promising insights and targets for tumor therapies.

Immunotherapy in liver cancer: overcoming the tolerogenic liver microenvironment

Liver cancer is a major global health concern, ranking among the top causes of cancer-related deaths worldwide. Despite advances in medical research, the prognosis for liver cancer remains poor, largely due to the inherent limitations of current therapies. Traditional treatments like surgery, radiation, and chemotherapy often fail to provide long-term remission and are associated with significant side effects. Immunotherapy has emerged as a promising avenue for cancer treatment, leveraging the body's immune system to target and destroy cancer cells. However, its application in liver cancer has been limited. One of the primary challenges is the liver's unique immune microenvironment, which can inhibit the effectiveness of immunotherapeutic agents. This immune microenvironment creates a barrier, leading to drug resistance and reducing the overall efficacy of treatment. Recent studies have focused on understanding the immunological landscape of liver cancer to develop strategies that can overcome these obstacles. By identifying the specific factors within the liver that contribute to immune suppression and drug resistance, researchers aim to enhance the effectiveness of immunotherapy. Prospective strategies include combining immunotherapy with other treatments, using targeted therapies to modulate the immune microenvironment, and developing new agents that can bypass or counteract the inhibitory mechanisms in the liver. These advancements hold promise for improving outcomes in liver cancer treatment.

Identification of novel M2 macrophage-related molecule ATP6V1E1 and its biological role in hepatocellular carcinoma based on machine learning algorithms

Hepatocellular carcinoma (HCC) remains the most prevalent form of primary liver cancer, characterized by late detection and suboptimal response to current therapies. The tumour microenvironment, especially the role of M2 macrophages, is pivotal in the progression and prognosis of HCC. We applied the machine learning algorithm-CIBERSORT, to quantify cellular compositions within the HCC TME, focusing on M2 macrophages. Gene expression profiles were analysed to identify key molecules, with ATP6V1E1 as a primary focus. We employed Gene Set Enrichment Analysis (GSEA) and Kaplan-Meier survival analysis to investigate the molecular pathways and prognostic significance of ATP6V1E1. A prognostic model was developed using multivariate Cox regression analysis based on ATP6V1E1-related molecules, and functional impacts were assessed through cell proliferation assays. M2 macrophages were the dominant cell type in the HCC TME, significantly correlating with adverse survival outcomes. ATP6V1E1 was robustly associated with advanced disease stages and poor prognostic features such as vascular invasion and elevated alpha-fetoprotein levels. GSEA linked high ATP6V1E1 expression to critical oncogenic pathways, including immunosuppression and angiogenesis, and reduced activity in metabolic processes like bile acid and fatty acid metabolism. The prognostic model stratified HCC patients into distinct risk categories, showing high predictive accuracy (1-year AUC = 0.775, 3-year AUC = 0.709 and 5-year AUC = 0.791). In vitro assays demonstrated that ATP6V1E1 knockdown markedly inhibited the proliferation of HCC cells. The study underscores the significance of M2 macrophages and ATP6V1E1 in HCC, highlighting their potential as therapeutic and prognostic targets.

Immunohistochemical Evaluation of Schlafen 11 (SLFN11) Expression in Cancer in the Search of Biomarker-Informed Treatment Targets: A Study of 127 Entities Represented by 6658 Tumors

Schlafen 11 (SLFN11), a DNA/RNA helicase, acts as a regulator of cellular response to replicative stress and irreversibly triggers replication block and cell death. Several preclinical in vitro studies and clinical trials established that SLFN11 expression predicts outcomes in patients with advanced cancer treated with DNA-damaging chemotherapeutics and more recently with poly(ADP-ribose) polymerase inhibitors. SLFN11 expression status remains unknown in many cancer types, especially in mesenchymal tumors. This study evaluated a cohort of well characterized 3808 epithelial and 2850 mesenchymal and neuroectodermal tumors for SLFN11 expression using immunohistochemistry. Nuclear SLFN11 expression was rare in some of the most common carcinomas, for example, hepatocellular (1%), prostatic (2%), colorectal (5%), or breast (16%) cancers. In contrast, other epithelial tumors including mesotheliomas (92%), clear cell renal cell carcinomas (79%), small cell lung cancers (76%), squamous cell carcinomas of the tonsil (89%) and larynx (71%), or ovarian serous carcinomas (69%) were mostly SLFN11-positive. Compared with epithelial malignancies, SLFN11 expression was overall higher in neuroectodermal and mesenchymal tumors. Most positive entities included desmoplastic small round cell tumor (100%), Ewing sarcoma (92%), undifferentiated sarcoma (92%), solitary fibrous tumor (91%), dedifferentiated liposarcoma (89%), synovial sarcoma (86%), and malignant peripheral nerve sheath tumor (85%). Also, this study identifies tumors with potentially worse response to DNA-damaging drugs including antibody drug conjugates due to the absence of SLFN11 expression. Such entities may benefit from alternative treatments or strategies to overcome SLFN11 deficiency-related drug resistance. Our approach and results should serve as a foundation for future biomarker-associated clinical trials.

CCL2 mediated IKZF1 expression promotes M2 polarization of glioma-associated macrophages through CD84-SHP2 pathway

The proneural-mesenchymal (PN-MES) transformation of glioma stem cells (GSCs) can significantly increase proliferation, invasion, chemotherapy tolerance, and recurrence. M2-like polarization of tumor-associated macrophages (TAMs) has a strong immunosuppressive effect, promoting tumor malignancy and angiogenesis. There is limited understanding on the interactions between GSCs and TAMs as well as their associated molecular mechanisms. In the present study, bioinformatics analysis, GSC and TAM co-culture, determination of TAM polarization phenotypes, and other in vitro experiments confirmed that CCL2 secreted by MES-GSCs promotes TAM-M2 polarization via the IKZF1-CD84-SHP2 pathway and PN-MES transformation of GSCs via the IKZF1-LRG1 pathway in TAMs. IKZF1 inhibitors could significantly reduce tumor volumes in animal glioma models and improve survival, as well as suppress TAM-M2 polarization and the GSC malignant phenotype. The results of this study indicate the important interaction between TAMs and GSCs in the glioma microenvironment as well as its role in tumor progression. The findings also suggest a novel target for follow-up clinical transformation research on the regulation of TAM function and GSCs malignant phenotype.

A New Nanoplatform Under NIR Released ROS Enhanced Photodynamic Therapy and Low Temperature Photothermal Therapy for Antibacterial and Wound Repair

Purpose

Skin injury, often caused by physical or medical mishaps, presents a significant challenge as wound healing is critical to restore skin integrity and tissue function. However, external factors such as infection and inflammation can hinder wound healing, highlighting the importance of developing biomaterials with antibiotic and wound healing properties to treat infections and inflammation. In this study, a novel photothermal nanomaterial (MMPI) was synthesized for infected wound healing by loading indocyanine green (ICG) on magnesium-incorporated mesoporous bioactive glass (Mg-MBG) and coating its surface with polydopamine (PDA).

Results

In this study, Mg-MBG and MMPI was synthesized via the sol-gel method and characterized it using various techniques such as scanning electron microscopy (SEM), the energy dispersive X-ray spectrometry (EDS) system and X-ray diffraction (XRD). The cytocompatibility of MMPI was evaluated by confocal laser scanning microscopy (CLSM), CCK8 assay, live/dead staining and F-actin staining of the cytoskeleton. The antibacterial efficiency was assessed using bacterial dead-acting staining, spread plate method (SPM) and TEM. The impact of MMPI on macrophage polarization was initially evaluated through flow cytometry, qPCR and ELISA. Additionally, an in vivo experiment was performed on a mouse model with skin excision infected. Histological analysis and RNA-seq analysis were utilized to analyze the in vivo wound healing and immunomodulation effect.

Conclusion

Collectively, the new photothermal and photodynamic nanomaterial (MMPI) can achieve low-temperature antibacterial activity while accelerating wound healing, holds broad application prospects.

Targeting cytokine and chemokine signaling pathways for cancer therapy

Cytokines are critical in regulating immune responses and cellular behavior, playing dual roles in both normal physiology and the pathology of diseases such as cancer. These molecules, including interleukins, interferons, tumor necrosis factors, chemokines, and growth factors like TGF-β, VEGF, and EGF, can promote or inhibit tumor growth, influence the tumor microenvironment, and impact the efficacy of cancer treatments. Recent advances in targeting these pathways have shown promising therapeutic potential, offering new strategies to modulate the immune system, inhibit tumor progression, and overcome resistance to conventional therapies. In this review, we summarized the current understanding and therapeutic implications of targeting cytokine and chemokine signaling pathways in cancer. By exploring the roles of these molecules in tumor biology and the immune response, we highlighted the development of novel therapeutic agents aimed at modulating these pathways to combat cancer. The review elaborated on the dual nature of cytokines as both promoters and suppressors of tumorigenesis, depending on the context, and discussed the challenges and opportunities this presents for therapeutic intervention. We also examined the latest advancements in targeted therapies, including monoclonal antibodies, bispecific antibodies, receptor inhibitors, fusion proteins, engineered cytokine variants, and their impact on tumor growth, metastasis, and the tumor microenvironment. Additionally, we evaluated the potential of combining these targeted therapies with other treatment modalities to overcome resistance and improve patient outcomes. Besides, we also focused on the ongoing research and clinical trials that are pivotal in advancing our understanding and application of cytokine- and chemokine-targeted therapies for cancer patients.

Hypoxia inhibits the iMo/cDC2/CD8+ TRMs immune axis in the tumor microenvironment of human esophageal cancer

BACKGROUND

Esophageal cancer (ESCA) is a form of malignant tumor associated with chronic inflammation and immune dysregulation. However, the specific immune status and key mechanisms of immune regulation in this disease require further exploration.

METHODS

To investigate the features of the human ESCA tumor immune microenvironment and its possible regulation, we performed mass cytometry by time of flight, single-cell RNA sequencing, multicolor fluorescence staining of tissue, and flow cytometry analyses on tumor and paracancerous tissue from treatment-naïve patients.

RESULTS

We depicted the immune landscape of the ESCA and revealed that CD8+ (tissue-resident memory CD8+ T cells (CD8+ TRMs) were closely related to disease progression. We also revealed the heterogeneity of CD8+ TRMs in the ESCA tumor microenvironment (TME), which was associated with their differentiation and function. Moreover, the subset of CD8+ TRMs in tumor (called tTRMs) that expressed high levels of granzyme B and immune checkpoints was markedly decreased in the TME of advanced ESCA. We showed that tTRMs are tumor effector cells preactivated in the TME. We then demonstrated that conventional dendritic cells (cDC2s) derived from intermediate monocytes (iMos) are essential for maintaining the proliferation of CD8+ TRMs in the TME. Our preliminary study showed that hypoxia can promote the apoptosis of iMos and impede the maturation of cDC2s, which in turn reduces the proliferative capacity of CD8+ TRMs, thereby contributing to the progression of cancer.

CONCLUSIONS

Our study revealed the essential antitumor roles of CD8+ TRMs and preliminarily explored the regulation of the iMo/cDC2/CD8+ TRM immune axis in the human ESCA TME.

The emerging role of Schlafen-11 (SLFN11) in predicting response to anticancer treatments: Focus on small cell lung cancer

Small cell lung cancer (SCLC) is characterized by a dismal prognosis. Many efforts have been made so far for identifying novel biomarkers for a personalized treatment for SCLC patients. Schlafen 11 (SLFN11) is a protein differently expressed in many cancers and recently emerged as a new potential biomarker. Lower expression of SLFN11 correlates with a worse prognosis in SCLC and other tumors. SLFN11 has a role in tumorigenesis, inducing replication arrest in the presence of DNA damage through the block of the replication fork. SLFN11 interacts also with chromatin accessibility, proteotoxic stress and mammalian target of rapamycin signalling pathway. The expression of SLFN11 is regulated by epigenetic mechanisms, including promoter methylation, histone deacetylation, and the histone methylation. The downregulation of SLFN11 correlates with a worse response to topoisomerase I and II inhibitors, alkylating agents, and poly ADP-ribose polymerase inhibitors in different cancer types. Some studies exploring strategies for overcoming drug resistance in tumors with low levels of SLFN11 showed promising results. One of these strategies includes the interaction with the Ataxia Telangiectasia and Rad3-related pathway, constitutively activated and leading to cell survival and tumor growth in the presence of low levels of SLFN11. Furthermore, the expression of SLFN11 is dynamic through time and different anticancer therapy and liquid biopsy seems to be an attractive tool for catching SLFN11 different expressions. Despite this, further investigations exploring SLFN11 as a predictive biomarker, its longitudinal changes, and new strategies to overcome drug resistances are needed.

LRP1 induces anti-PD-1 resistance by modulating the DLL4-NOTCH2-CCL2 axis and redirecting M2-like macrophage polarisation in bladder cancer

The tumour microenvironment (TME) drives bladder cancer (BLCA) progression. Targeting the TME has emerged as a promising strategy for BLCA treatment in recent years. Furthermore, checkpoint blockade therapies are only beneficial for a minority of patients with BLCA, and drug resistance is a barrier to achieving significant clinical effects of anti-programmed cell death protein-1 (PD-1)/programmed death protein ligand-1 (PD-L1) therapy. In this study, higher low-density lipoprotein receptor-related protein 1 (LRP1) levels were related to a poorer prognosis for patients with various cancers, including those with higher grades and later stages of BLCA. Enrichment analysis demonstrated that LRP1 plays a role in the epithelial-mesenchymal transition (EMT), NOTCH signalling pathway, and ubiquitination. LRP1 knockdown in BLCA cells delayed BLCA progression both in vivo and in vitro. Furthermore, LRP1 knockdown suppressed EMT, reduced DLL4-NOTCH2 signalling activity, and downregulated M2-like macrophage polarisation. Patients with BLCA and higher LRP1 levels responded weakly to anti-PD-1 therapy in the IMvigor210 cohort. Moreover, LRP1 knockdown enhanced the therapeutic effects of anti-PD-1 in mice. Taken together, our findings suggest that LRP1 is a potential target for improving the efficacy of anti-PD-1/PD-L1 therapy by preventing EMT and M2-like macrophage polarisation by blocking the DLL4-NOTCH2 axis.

Repolarization of Immunosuppressive Macrophages by Targeting SLAMF7-Regulated CCL2 Signaling Sensitizes Hepatocellular Carcinoma to Immunotherapy

Immune checkpoint inhibitors have limited efficacy in hepatocellular carcinoma (HCC). Macrophages are the most abundant immune cells in HCC, suggesting that a better understanding of the intrinsic processes by which tumor cells regulate macrophages could help identify strategies to improve response to immunotherapy. As signaling lymphocytic activation molecule (SLAM) family members regulate various immune functions, we investigated the role of specific SLAM receptors in the immunobiology of HCC. Comparison of the transcriptomic landscapes of immunotherapy-responsive and nonresponsive patients with advanced HCC identified SLAMF7 upregulation in immunotherapy-responsive HCC, and patients with HCC who responded to immunotherapy also displayed higher serum levels of SLAMF7. Loss of Slamf7 in liver-specific knockout mice led to increased hepatocarcinogenesis and metastasis, elevated immunosuppressive macrophage infiltration, and upregulated PD-1 expression in CD8+ T cells. HCC cell-intrinsic SLAMF7 suppressed MAPK/ATF2-mediated CCL2 expression to regulate macrophage migration and polarization in vitro. Mechanistically, SLAMF7 associated with SH2 domain-containing adaptor protein B (SHB) through its cytoplasmic 304 tyrosine site to facilitate the recruitment of SHIP1 to SLAMF7 and inhibit the ubiquitination of TRAF6, thereby attenuating MAPK pathway activation and CCL2 transcription. Pharmacological antagonism of the CCL2/CCR2 axis potentiated the therapeutic effect of anti-PD-1 antibody in orthotopic HCC mouse models with low SLAMF7 expression. In conclusion, this study highlights SLAMF7 as a regulator of macrophage function and a potential predictive biomarker of immunotherapy response in HCC. Strategies targeting CCL2 signaling to induce macrophage repolarization in HCC with low SLAMF7 might enhance the efficacy of immunotherapy.

SIGNIFICANCE

CCL2 upregulation caused by SLAMF7 deficiency in hepatocellular carcinoma cells induces immunosuppressive macrophage polarization and confers resistance to immune checkpoint blockade, providing potential biomarkers and targets to improve immunotherapy response in patients.

STC1 competitively binding βPIX enhances melanoma progression via YAP nuclear translocation and M2 macrophage recruitment through the YAP/CCL2/VEGFA/AKT feedback loop

This study investigates the role of Stanniocalcin-1 (STC1) in melanoma progression, with a focus on its impact on metastasis, angiogenesis, and immune evasion. Systematic bioinformatics analysis revealed the potential influence of STC1 dysregulation on prognosis, immune cell infiltration, response to immune therapy, and cellular functions. In vitro assays were conducted to assess the proliferation, invasion, migration, and angiogenesis capabilities of A375 cells. In vivo experiments utilizing C57BL/6 J mice established a lung metastasis model using B16-F10 cells to evaluate macrophage infiltration and M2 polarization. A Transwell co-culture system was employed to explore the crosstalk between melanoma and macrophages. Molecular interactions among STC1, YAP, βPIX, and CCL2 are investigated using mass spectrometry, Co-Immunoprecipitation, Dual-Luciferase Reporter Assay, and Chromatin Immunoprecipitation experiments. STC1 was found to enhance lung metastasis by promoting the recruitment and polarization of M2 macrophages, thereby fostering an immunosuppressive microenvironment. Mechanistically, STC1 competes with YAP for binding to βPIX within the KER domain in melanoma cells, leading to YAP activation and subsequent CCL2 upregulation. CCL2-induced M2 macrophages secrete VEGFA, which enhances tumor vascularization and increases STC1 expression via the AKT signaling pathway in melanoma cells, establishing a pro-metastatic feedback loop. Notably, STC1-induced YAP activation increases PD-L1 expression, promoting immune evasion. Silencing STC1 enhances the efficacy of PD-1 immune checkpoint therapy in mice. This research elucidates STC1's role in melanoma metastasis and its complex interactions with tumor-associated macrophages, proposing STC1 as a potential therapeutic target for countering melanoma metastasis and augmenting the efficacy of PD-1 immunotherapy.

Fibroblast activation protein promotes progression of hepatocellular carcinoma via regulating the immunity

Fibroblast activation protein (FAP) has been indicated to express in cancer-associated fibroblasts (CAFs) in most cancers. This work was dedicated to exploring FAP's effects on hepatocellular carcinoma (HCC). The data were extracted from The Cancer Genome Atlas, Gene Expression Omnibus, ImmPort, and Reactome databases. The correlation between FAP and HCC patients' prognosis was explored via survival analysis. The qRT-PCR and western blot analysis were used to analyze the FAP mRNA and protein expression levels, respectively. The cell proliferation and apoptosis were determined using the cell counting kit-8 assay kit and Annexin V-FITC/PI apoptosis kit, respectively. The HCC patients with FAP overexpression displayed a worse prognosis. The FAP expression was positively associated with the infiltration levels of tumor purity, B cell, CD8 + T cell, CD4 + T cell, macrophage, neutrophil, and dendritic cell. The optimal nine immune related genes were screened between two groups (FAP high vs. low). Moreover, we identified 24 energy metabolism related genes (FAP high vs. low) and these 24 genes were highly expressed in the high FAP expression group. The FAP expression had a significant positive correlation with the expression of PD-1, CTLA4, PDL-1, and PDL-2. The FAP overexpression promoted proliferation and migration while inhibiting the apoptosis of HCC cells. The FAP overexpression promoted the progression of HCC by regulating the immunity to affect the prognosis of HCC patients, thereby serving as a poor prognostic marker for HCC patients.

Exploiting the immune system in hepatic tumor targeting: Unleashing the potential of drugs, natural products, and nanoparticles

Hepatic tumors present a formidable challenge in cancer therapeutics, necessitating the exploration of novel treatment strategies. In recent years, targeting the immune system has attracted interest to augment existing therapeutic efficacy. The immune system in hepatic tumors includes numerous cells with diverse actions. CD8+ T lymphocytes, T helper 1 (Th1) CD4+ T lymphocytes, alternative M1 macrophages, and natural killer (NK) cells provide the antitumor immunity. However, Foxp3+ regulatory CD4+ T cells (Tregs), M2-like tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs) are the key immune inhibitor cells. Tumor stroma can also affect these interactions. Targeting these cells and their secreted molecules is intriguing for eliminating malignant cells. The current review provides a synopsis of the immune system components involved in hepatic tumor expansion and highlights the molecular and cellular pathways that can be targeted for therapeutic intervention. It also overviews the diverse range of drugs, natural products, immunotherapy drugs, and nanoparticles that have been investigated to manipulate immune responses and bolster antitumor immunity. The review also addresses the potential advantages and challenges associated with these approaches.

RNA processing modification mediated subtypes illustrate the distinctive features of tumor microenvironment in hepatocellular carcinoma

Multiple transcript isoforms of genes can be formed by processing and modifying the 5' and 3' ends of RNA. Herein, the aim of this study is to uncover the characteristics of RNA processing modification (RPM) in hepatocellular carcinoma (HCC), and to identify novel biomarkers and potential targets for treatment. Firstly, integrated bioinformatics analysis was carried out to identify risk prognostic RPM regulators (RPMRs). Then, we used these RPMRs to identify subtypes of HCC and explore differences in immune microenvironment and cellular function improvement pathways between the sub-types. Finally, we used the principal component analysis algorithms to estimate RPMscore, which were applied to 5 cohorts. Lower RPMscore among patients correlated with a declined survival rate, increased immune infiltration, and raised expression of immune checkpoints, aligning with the "immunity tidal model theory". The RPMscore exhibited robust, which was validated in multiple datasets. Mechanistically, low RPMscore can create an immunosuppressive microenvironment in HCC by manipulating tumor-associated macrophages. Preclinically, patients with high RPMscore might benefit from immunotherapy. The RPMscore is helpful in clustering HCC patients with distinct prognosis and immunotherapy. Our RPMscore model can help clinicians to select personalized therapy for HCC patients, and RPMscore may act a part in the development of HCC.

New insights into the role of macrophages in cancer immunotherapy

Macrophages are the main component of the tumor microenvironment, which are differentiated from monocytes in the blood and play an important role in cancer development. Tumor-associated macrophages (TAMs) can promote tumor growth, invasion, metastasis, and resistance to anti-programmed death receptor 1 therapy by regulating programmed cell death ligand 1 expression and interacting with other immune cells in the tumor microenvironment. However, when activated properly, macrophages can also play an anti-tumor role by enhancing the phagocytosis and cytotoxicity of tumor cells. TAM is associated with poor prognosis and drug resistance in patients treated with immunotherapy, indicating that macrophages are attractive targets for combined therapy in cancer treatment. Combination of targeting TAMs and immunotherapy overcomes the drug resistance and achieved excellent results in some cancers, which may be a promising strategy for cancer treatment in the future. Herein, we review the recent findings on the role of macrophages in tumor development, metastasis, and immunotherapy. We focus mainly on macrophage≥centered therapy, including strategies to deplete and reprogram TAMs, which represent the potential targets for improving tumor immunotherapy efficacy.

Macrophages in acne vulgaris: mediating phagocytosis, inflammation, scar formation, and therapeutic implications

Macrophages serve as a pivotal nexus in the pathogenesis of acne vulgaris, orchestrating both the elimination of Cutibacterium acnes (C. acnes) and lipid metabolic regulation while also possessing the capacity to exacerbate inflammation and induce cutaneous scarring. Additionally, recent investigations underscore the therapeutic potential inherent in macrophage modulation and challenge current anti-inflammatory strategies for acne vulgaris. This review distills contemporary advances, specifically examining the dual roles of macrophages, underlying regulatory frameworks, and emergent therapeutic avenues. Such nuanced insights hold the promise of guiding future explorations into the molecular etiology of acne and the development of more efficacious treatment modalities.

Chemokine CCL21 determines immunotherapy response in hepatocellular carcinoma by affecting neutrophil polarization

BACKGROUND

The efficacy of immune checkpoint inhibitors (ICIs) in hepatocellular carcinoma (HCC) is poor and great heterogeneity among individuals. Chemokines are highly correlated with tumor immune response. Here, we aimed to identify an effective chemokine for predicting the efficacy of immunotherapy in HCC.

METHODS

Chemokine C-C motif ligand 21 (CCL21) was screened by transcriptomic analysis in tumor tissues from HCC patients with different responses to ICIs. The least absolute shrinkage and selection operator (LASSO) regression analysis was conducted to construct a predictive nomogram. Neutrophils in vitro and HCC subcutaneous tumor model in vivo were applied to explore the role of CCL21 on the tumor microenvironment (TME) of HCC.

RESULTS

Transcriptome analysis showed that CCL21 level was much higher in HCC patients with response to immunotherapy. The predictive nomogram was constructed and validated as a classifier. CCL21 could inhibit N2 neutrophil polarization by suppressing the activation of nuclear factor kappa B (NF-κB) pathway. In addition, CCL21 enhanced the therapeutic efficacy of ICIs.

CONCLUSION

CCL21 may serve as a predictive biomarker for immunotherapy response in HCC patients. High levels of CCL21 in TME inhibit immunosuppressive polarization of neutrophils. CCL21 in combination with ICIs may offer a novel therapeutic strategy for HCC.

Copper-Zinc-Doped Bilayer Bioactive Glasses Loaded Hydrogel with Spatiotemporal Immunomodulation Supports MRSA-Infected Wound Healing

Developing biomaterials with antimicrobial and wound-healing activities for the treatment of wound infections remains challenging. Macrophages play non-negligible roles in healing infection-related wounds. In this study, a new sequential immunomodulatory approach is proposed to promote effective and rapid wound healing using a novel hybrid hydrogel dressing based on the immune characteristics of bacteria-associated wounds. The hydrogel dressing substrate is derived from a porcine dermal extracellular matrix (PADM) and loaded with a new class of bioactive glass nanoparticles (BGns) doped with copper (Cu) and zinc (Zn) ions (Cu-Zn BGns). This hybrid hydrogel demonstrates a controlled release of Cu2+ and Zn2+ and sequentially regulates the phenotypic transition of macrophages from M1 to M2 by alternately activating nucleotide-binding oligomerization domain (NOD) and inhibiting mitogen-activated protein kinases (MAPK) signaling pathways. Additionally, its dual-temporal bidirectional immunomodulatory function facilitates enhanced antibacterial activity and wound healing. Hence, this novel hydrogel is capable of safely and efficiently accelerating wound healing during infections. As such, the design strategy provides a new direction for exploring novel immunomodulatory biomaterials to address current clinical challenges related to the treatment of wound infections.

Macrophage-related therapeutic strategies: Regulation of phenotypic switching and construction of drug delivery systems

Macrophages, as highly phenotypic plastic immune cells, play diverse roles in different pathological conditions. Changing and controlling the phenotypes of macrophages is considered a novel potential therapeutic intervention. Meanwhile, specific transmembrane proteins anchoring on the surface of the macrophage membrane are relatively conserved, supporting its functional properties, such as inflammatory chemotaxis and tumor targeting. Thus, a series of drug delivery systems related to specific macrophage membrane proteins are commonly used to treat chronic inflammatory diseases. This review summarizes macrophages-based strategies for chronic diseases, discusses the regulation of macrophage phenotypes and their polarization processes, and presents how to design and apply the site-specific targeted drug delivery systems in vivo based on the macrophages and their derived membrane receptors. It aims to provide a better understanding of macrophages in immunoregulation and proposes macrophages-based targeted therapeutic approaches for chronic diseases.

Biomarkers predicting the efficacy of immune checkpoint inhibitors in hepatocellular carcinoma

In recent years, immune checkpoint inhibitors (ICIs) have emerged as a transformative approach in treating advanced hepatocellular carcinoma (HCC). Despite their success, challenges persist, including concerns about their effectiveness, treatment costs, frequent occurrence of treatment-related adverse events, and tumor hyperprogression. Therefore, it is imperative to identify indicators capable of predicting the efficacy of ICIs treatment, enabling optimal patient selection to maximize clinical benefits while minimizing unnecessary toxic side effects and economic losses. This review paper categorizes prognostic biomarkers of ICIs treatment into the following categories: biochemical and cytological indicators, tumor-related markers, imaging and personal features, etiology, gut microbiome, and immune-related adverse events (irAEs). By organizing these indicators systematically, we aim to guide biomarker exploration and inform clinical treatment decisions.

The current status and future of PD-L1 in liver cancer

The application of immunotherapy in tumor, especially immune checkpoint inhibitors (ICIs), has played an important role in the treatment of advanced unresectable liver cancer. However, the efficacy of ICIs varies greatly among different patients, which has aroused people's attention to the regulatory mechanism of programmed death ligand-1 (PD-L1) in the immune escape of liver cancer. PD-L1 is regulated by multiple levels and signaling pathways in hepatocellular carcinoma (HCC), including gene variation, epigenetic inheritance, transcriptional regulation, post-transcriptional regulation, and post-translational modification. More studies have also found that the high expression of PD-L1 may be the main factor affecting the immunotherapy of liver cancer. However, what is the difference of PD-L1 expressed by different types of cells in the microenvironment of HCC, and which type of cells expressed PD-L1 determines the effect of tumor immunotherapy remains unclear. Therefore, clarifying the regulatory mechanism of PD-L1 in liver cancer can provide more basis for liver cancer immunotherapy and combined immune treatment strategy. In addition to its well-known role in immune regulation, PD-L1 also plays a role in regulating cancer cell proliferation and promoting drug resistance of tumor cells, which will be reviewed in this paper. In addition, we also summarized the natural products and drugs that regulated the expression of PD-L1 in HCC.

ETV4 facilitates angiogenesis in hepatocellular carcinoma by upregulating MMP14 expression

Abnormal vascularization plays a crucial role in cell proliferation, tumor invasion and metastasis of hepatocellular carcinoma (HCC). It has been reported that ETV4 functions as an oncogenic gene in driving the carcinogenesis and progression, and promoting invasion and metastasis of HCC. However, the function of ETV4 on angiogenesis in HCC remains unclear. In the current study, immunohistochemistry showed that knockdown of ETV4 reduced angiogenesis in HCC xenograft tumor tissues. In vitro, tube formation assay verified that ETV4 expression promoted angiogenesis through simulating the angiogenic environment in HCC cells. Transcriptome sequencing indicated that MMP14 was one of the differentially expressed genes enriched in angiogenesis process. Subsequently, it was confirmed that MMP14 was regulated by ETV4 at the transcription level in HCC cells, clinical tissue samples and online databases. Further, we demonstrated that MMP14 induced angiogenesis in ETV4-mediated HCC microenvironment. Collectively, this research further reveals the biological mechanism of ETV4 in promoting the migration and invasion of HCC, and provides novel mechanistic insights and strategic guidance for anti-angiogenic therapy in HCC.