Cancer-Associated Fibroblast-Mediated Cellular Crosstalk Supports Hepatocellular Carcinoma Progression

Scutellaria barbata D.Don and Scleromitrion diffusum (Willd.) R.J.Wang inhibits the progression of triple negative breast cancer though the activation inhibition of NF-κB triggered by CAFs-derived IL6

ETHNOPHARMACOLOGICAL RELEVANCE

The treatment options for triple-negative breast cancer (TNBC) are limited. Traditional Chinese Medicine (TCM) plays an important role in the treatment of TNBC. The herb pair Scutellaria barbata D.Don and Scleromitrion diffusum (Willd.) R.J.Wang (SH) is commonly used in clinical practice for its anti-tumor properties. It has been proven to have good therapeutic effects on tumor-related diseases, but the underlying molecular mechanisms are not yet fully explained.

AIM OF STUDY

Through bioinformatics, it was validated that IL6, primarily derived from cancer-associated fibroblasts (CAFs), is associated with poor prognosis. Additionally, cell and animal experiments confirmed that SH inhibits tumor proliferation, migration, and growth in an orthotopic tumor model by suppressing the IL6/NF-κB pathway.

MATERIALS AND METHODS

GEO, TCGA and HPA databases were used to analyze the prognostic value of CAFs and IL6, then IL6 resource was detected. After the bioinformatics, the influence of CAFs and CAFs-derived IL6 on TNBC was verified by experiments both in vitro and in vivo. Cell clone formation assay, wound-Healing assay, and Transwell assay were used to detect the promotion of CAFs and CAFs-derived IL6 and the inhibition of SH in vitro. TNBC model in mice was used to prove the promotion of CAFs and CAFs-derived IL6 and the inhibition of SH in vivo. The biological pathway of NF-κB was explored by western blotting through detecting unique molecules.

RESULTS

Bioinformatics analysis revealed that higher proportion of CAFs and elevated level of IL6 were significantly associated with poor prognosis in TNBC. At the same time, IL6 was proved predominantly derived from CAFs. After the indication of bioinformatics, experiments in vitro demonstrated that both CAFs and IL6 could enhance the clone formation and migration ability of MDA-MD-231 cells (231), furthermore, the promotion of CAFs was related with the level of IL6. Based on these data, mechanism was detected that CAFs-derived IL6 enhancement was closely related to the activation of NF-κB signaling pathway, while the activation can be reduced by SH. In the end, the promotion of CAFs/CAFs-derived IL6/NF-κB and the efficacy of SH inhibition were both confirmed by experiments in vivo.

CONCLUSIONS

Bioinformatics data indicates that higher proportion of CAFs and higher level of CAFs-derived IL6 are significantly related to poorer survival of TNBC. CAFs and CAFs-derived IL6 were proved to promote the progression of TNBC both in vitro and in vivo, and the process of which was significantly related to the activation of NF-κB. SH inhibited the progress of TNBC, which was proved to be closely related to CAFs/CAFs-derived IL6/NF-κB.

Machine-Learning-Based Identification of Key Feature RNA-Signature Linked to Diagnosis of Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is the third prime cause of malignancy-related mortality worldwide. Early and accurate identification of HCC is crucial for good prognosis, efficacy of therapy, and survival rates of the patients. We aimed to develop a machine-learning model incorporating differentially expressed RNA signatures with laboratory parameters to construct an RNA signature-based diagnostic model for HCC.

Methods

We have used five classifiers (KNN, RF, SVM, LGBM, and DNNs) to predict the liver disease (HCC). The classifiers were trained on 187 samples and then tested on 80 samples. The model included 22 features (age, sex, smoking, cirrhosis, non-cirrhosis, albumin, ALT, AST bilirubin (total and direct), INR, AFP, HBV Ag, HCV Abs, RQmiR-1298, RQmiR-1262, RQmiR-106b-3p, RQmRNARAB11A, and RQSTAT1, RQmRNAATG12, RQLnc-WRAP53, RQLncRNA- RP11-513I15.6).

Results

LGBM achieved the highest accuracy of 98.75% in predicting HCC among all models surpassing Random Forest (96.25%), DNN (91.25%), SVC (88.75%), and KNN (87.50%).

Conclusion

Our machine-learning model incorporating the expression data of RAB11A/STAT1/ATG12/miR-1262/miR-1298/miR-106b-3p/lncRNA-RP11-513I15.6/lncRNA-WRAP53 signature and clinical data represents a potential novel diagnostic model for HCC.

The axis of tumor-associated macrophages, extracellular matrix proteins, and cancer-associated fibroblasts in oncogenesis

The extracellular matrix (ECM) is a complex, dynamic network of multiple macromolecules that serve as a crucial structural and physical scaffold for neighboring cells. In the tumor microenvironment (TME), ECM proteins play a significant role in mediating cellular communication between cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs). Revealing the ECM modification of the TME necessitates the intricate signaling cascades that transpire among diverse cell populations and ECM proteins. The advent of single-cell sequencing has enabled the identification and refinement of specific cellular subpopulations, which has substantially enhanced our comprehension of the intricate milieu and given us a high-resolution perspective on the diversity of ECM proteins. However, it is essential to integrate single-cell data and establish a coherent framework. In this regard, we present a comprehensive review of the relationships among ECM, TAMs, and CAFs. This encompasses insights into the ECM proteins released by TAMs and CAFs, signaling integration in the TAM-ECM-CAF axis, and the potential applications and limitations of targeted therapies for CAFs. This review serves as a reliable resource for focused therapeutic strategies while highlighting the crucial role of ECM proteins as intermediates in the TME.

Drug resistance and tumor immune microenvironment: An overview of current understandings (Review)

The use of antitumor drugs represents a reliable strategy for cancer therapy. Unfortunately, drug resistance has become increasingly common and contributes to tumor metastasis and local recurrence. The tumor immune microenvironment (TME) consists of immune cells, cytokines and immunomodulators, and collectively they influence the response to treatment. Epigenetic changes including DNA methylation and histone modification, as well as increased drug exportation have been reported to contribute to the development of drug resistance in cancers. In the past few years, the majority of studies on tumors have only focused on the development and progression of a tumor from a mechanistic standpoint; few studies have examined whether the changes in the TME can also affect tumor growth and drug resistance. Recently, emerging evidence have raised more concerns regarding the role of TME in the development of drug resistance. In the present review, it was discussed how the suppressive TME adapts to drug resistance characterized by the cooperation of immune cells, cytokines, immunomodulators, stromal cells and extracellular matrix. Furthermore, it was reviewed how these immunological or metabolic changes alter immuno‑surveillance and thus facilitate tumor drug resistance. In addition, potential targets present in the TME for developing novel therapeutic strategies to improve individualized therapy for cancer treatment were revealed.

Roles of the tumor microenvironment in the resistance to programmed cell death protein 1 inhibitors in patients with gastric cancer

Despite the continuous developments and advancements in the treatment of gastric cancer (GC), which is one of the most prevalent types of cancer in China, the overall survival is still poor for most patients with advanced GC. In recent years, with the progress in tumor immunology research, attention has shifted toward immunotherapy as a therapeutic approach for GC. Programmed cell death protein 1 (PD-1) inhibitors, as novel immunosuppressive medications, have been widely utilized in the treatment of GC. However, many patients are still resistant to PD-1 inhibitors and experience recurrence in the advanced stages of PD-1 immunotherapy. To reduce the occurrence of drug resistance and recurrence in GC patients receiving PD-1 immunotherapy, to maximize the clinical activity of immunosuppressive drugs, and to elicit a lasting immune response, it is essential to research the tumor microenvironment mechanisms leading to PD-1 inhibitor resistance in GC patients. This article reviews the progress in studying the factors influencing the resistance to PD-1 inhibitors in the GC tumor microenvironment, aiming to provide insights and a basis for reducing resistance to PD-1 inhibitors for GC patients in the future.

Extracellular vesicles in the HCC microenvironment: Implications for therapy and biomarkers

Hepatocellular carcinoma (HCC) stands as the sixth most prevalent cancer and the third leading cause of cancer mortality globally. Despite surgical resection being the preferred approach for early-stage HCC, most patients are diagnosed at intermediate to advanced stages, limiting treatment options to chemotherapy and immunotherapy, which often yield poor outcomes. Extracellular vesicles (EVs), minute lipid-bilayered particles released by diverse cells under various physiological and pathological conditions, are crucial for mediating communication between cells. Mounting evidence indicates that EVs sourced from different cells can profoundly influence the HCC tumor microenvironment (TME), thereby affecting the progression of HCC. Given their immunogenicity and liver-targeting properties, these EVs not only hold promise for HCC treatment but also provide avenues for advancing early diagnostic methods and assessing prognosis. This review not only describes the function of EVs within the HCC tumor microenvironment but also analyzes their therapeutic advantages and explores their significance in various therapeutic approaches for HCC, including chemotherapy, immunotherapy, combination therapy, and their role as innovative drug delivery carriers. Furthermore, it highlights the potential of EVs as biomarkers for the diagnosis and prognosis of HCC.

Spatial transcriptomics reveals tumor-derived SPP1 induces fibroblast chemotaxis and activation in the hepatocellular carcinoma microenvironment

BACKGROUND

The tumor microenvironment (TME) exerts profound effects on tumor progression and therapeutic efficacy. In hepatocellular carcinoma (HCC), the TME is enriched with cancer-associated fibroblasts (CAFs), which secrete a plethora of cytokines, chemokines, and growth factors that facilitate tumor cell proliferation and invasion. However, the intricate architecture of the TME in HCC, as well as the mechanisms driving interactions between tumor cells and CAFs, remains largely enigmatic.

METHODS

We analyzed 10 spatial transcriptomics and 12 single-cell transcriptomics samples sourced from public databases, complemented by 20 tumor tissue samples from liver cancer patients obtained in a clinical setting.

RESULTS

Our findings reveal that tumor cells exhibiting high levels of SPP1 are preferentially localized adjacent to hepatic stellate cells (HSCs). The SPP1 secreted by these tumor cells interacts with the CD44 receptor on HSCs, thereby activating the PI3K/AKT signaling pathway, which promotes the differentiation of HSCs into CAFs. Notably, blockade of the CD44 receptor effectively abrogates this interaction. Furthermore, in vivo studies demonstrate that silencing SPP1 expression in tumor cells significantly impairs HSC differentiation into CAFs, leading to a reduction in tumor volume and collagen deposition within the tumor stroma.

CONCLUSIONS

This study delineates the SPP1-CD44 signaling axis as a pivotal mechanism underpinning the interaction between tumor cells and CAFs. Targeting this pathway holds potential to mitigate liver fibrosis and offers novel therapeutic perspectives for liver cancer management.

Endosialin-positive CAFs promote hepatocellular carcinoma progression by suppressing CD8+ T cell infiltration

BACKGROUND AND AIMS

Endosialin, also known as tumor endothelial marker1 or CD248, is a transmembrane glycoprotein that is mainly expressed in cancer-associated fibroblasts (CAFs) in hepatocellular carcinoma (HCC). Our previous study has found that endosialin-positive CAFs could recruit and induce the M2 polarization of macrophages in HCC. However, whether they may regulate other types of immune cells to promoting HCC progression is not known.

APPROACH AND RESULTS

The growth of both subcutaneous and orthotopic HCC tumors was significantly inhibited in endosialin knockout (ENKO) mice. Single-cell sequencing and flow cytometry analysis showed that tumor tissues from ENKO mice had increased CD8+ T cell infiltration. Mixed HCC tumor with Hepa1-6 cells and endosialin knockdown fibroblasts also showed inhibited growth and increased CD8+ T cell infiltration. Data from in vitro co-culture assay, chemokine array and antibody blocking assay, RNA-seq and validation experiments showed that endosialin inhibits the phosphorylation and nuclear translocation of STAT1 in CAFs. This inhibition leads to a decrease in CXCL9/10 expression and secretion, resulting in the suppression of CD8+ T cell infiltration. High level of endosialin protein expression was correlated with low CD8+ T infiltration in the tumor tissue of HCC patients. The combination therapy of endosialin antibody and PD-1 antibody showed synergistic antitumor effect compared with either antibody used individually.

CONCLUSIONS

Endosialin could inhibit CD8+ T cell infiltration by inhibiting the expression and secretion of CXCL9/10 in CAFs, thus promote HCC progression. Combination therapy with endosialin antibody could increase the antitumor effect of PD-1 antibody in HCC, which may overcome the resistance to PD-1 blockade.

Cancer associated fibroblasts and metabolic reprogramming: unraveling the intricate crosstalk in tumor evolution

Metabolic reprogramming provides tumors with an energy source and biofuel to support their survival in the malignant microenvironment. Extensive research into the intrinsic oncogenic mechanisms of the tumor microenvironment (TME) has established that cancer-associated fibroblast (CAFs) and metabolic reprogramming regulates tumor progression through numerous biological activities, including tumor immunosuppression, chronic inflammation, and ecological niche remodeling. Specifically, immunosuppressive TME formation is promoted and mediators released via CAFs and multiple immune cells that collectively support chronic inflammation, thereby inducing pre-metastatic ecological niche formation, and ultimately driving a vicious cycle of tumor proliferation and metastasis. This review comprehensively explores the process of CAFs and metabolic regulation of the dynamic evolution of tumor-adapted TME, with particular focus on the mechanisms by which CAFs promote the formation of an immunosuppressive microenvironment and support metastasis. Existing findings confirm that multiple components of the TME act cooperatively to accelerate the progression of tumor events. The potential applications and challenges of targeted therapies based on CAFs in the clinical setting are further discussed in the context of advancing research related to CAFs.

Cell-cell crosstalk between fat cells and immune cells

Obesity is a metabolic disorder with pandemic-like implications, lacking viable pharmaceutical treatments currently. Thermogenic adipose tissues, including brown and beige adipose tissues, play an essential role in regulating systemic energy homeostasis and have emerged as appealing therapeutic targets for the treatment of obesity and obesity-related diseases. The function of adipocytes is subject to complex regulation by a cellular network of immune signaling pathways in response to environmental signals. However, the specific regulatory roles of immune cells in thermogenesis and relevant involving mechanisms are still not well understood. Here, we concentrate on our present knowledge of the interaction between thermogenic adipocytes and immune cells and present an overview of cellular and molecular mechanisms underlying immunometabolism in adipose tissues. We discuss cytokines, especially interleukins, which originate from widely variable sources, and their impacts on the development and function of thermogenic adipocytes. Moreover, we summarize the neuroimmune regulation in heat production and expand a new mode of intercellular communication mediated by mitochondrial transfer. The crosstalk between immune cells and adipocytes achieves adipose tissue homeostasis and systemic energy balance. A deep understanding of this intricate interaction would provide evidence for improving thermogenic efficiency by remodeling the immune microenvironment. Interventions based on these factors show a high potential to prevent adverse metabolic outcomes in patients with obesity.

The CXCR2 chemokine receptor: A new target for gastric cancer therapy

Gastric cancer (GC) is one of the most common malignant tumors in the world, and current treatments are still based on surgery and drug therapy. However, due to the complexity of immunosuppression and drug resistance, the treatment of gastric cancer still faces great challenges. Chemokine receptor 2 (CXCR2) is one of the most common therapeutic targets in targeted therapy. As a G protein-coupled receptor, CXCR2 and its ligands play important roles in tumorigenesis and progression. The abnormal expression of these genes in cancer plays a decisive role in the recruitment and activation of white blood cells, angiogenesis, and cancer cell proliferation, and CXCR2 is involved in various stages of tumor development. Therefore, interfering with the interaction between CXCR2 and its ligands is considered a possible target for the treatment of various tumors, including gastric cancer.

Predicting Survival Signature of Bladder Cancer Related to Cancer-Associated Fibroblast (CAF) Constructed by Intersecting Genes in TCGA and GEO

Bladder cancer was one of the most common carcinomas around the world. However, the mechanism of the disease still remained to be investigated. We expected to establish a prognostic survival model with 9 prognostic genes to predict overall survival (OS) in patients of bladder cancer. The gene expression data of bladder cancer were obtained from TCGA and GEO datasets. TCGA and GEO datasets were used for screening prognostic genes along with developing and validating a 9-gene prognostic survival model by method of weighted gene co-expression network analysis (WGCNA) and LASSO with Cox regression. The relative analysis of evaluate tumor burden mutation (TBM), GO, KEGG, chemotherapy drug and functional pathway were also performed based on CAF-related mRNAs. 151 Overlapping CAF-related genes were distinguished after intersecting differentially expressed genes from 945 genes in TCGA and 491 genes in GEO dataset. 9 Prognostic genes (MSRB2, AGMAT, KLF6, DDAH2, GADD45B, SERPINE2, STMN3, TEAD2, and COMP) were used for construction of prognostic model after LASSO with Cox regression. Receiver operating characteristic (ROC) curves showed a good survival prediction by this model. Functional analysis indicated chemokine, cytokine, ECM interaction, oxidative stress and apoptosis were highly appeared. Potential drugs targeted different CAF-related genes like vemurafenib, irofulven, ghiotepa, and idarubicin were found as well. We constructed a novel 9 CAF-related mRNAs prognostic model and explored the gene expression and potential functional information of related genes, which might be worthy of clinical application. In addition, potential chemotherapy drugs could provide useful insights into the potential clinical treatment of bladder cancer.

Characterization of the tumor microenvironment in breast cancer brain metastasis

Objective

The difference in the tumor microenvironment (TME) between primary breast cancer (PBC) and breast cancer brain metastasis (BCBM) is still unknown. Herein, we present the landscape of the TME in PBC and BCBM to better understand the process of BCBM.

Methods

The Gene Expression Omnibus (GEO) database was used to obtain suitable PBC and BCBM data. Hub genes that were differentially expressed between the two groups were searched. Gene Ontology (GO) and KEGG were used to define the gene's function. Single-cell data were also analyzed to determine the difference between PBC and BCBM.

Results

Two datasets (GSE100534 and GSE125989) were used to search for hub genes, and 79 genes were either upregulated or downregulated between the two groups. Four hub genes (COL1A1, PDGFR, MMP3 and FZD7) were related to prognosis. GO and KEGG analyses showed that extracellular matrix and focal adhesion play major roles in the metastasis process. Another two datasets (GSE176078 and GSE186344) were enrolled for single-cell analysis. Single-cell analysis demonstrated that immune cells (66.6 %) form the main part of PBC, while cancer-associated fibroblasts (CAFs) (21.7 %) are the main component of BCBM. Immune cell proportion analysis showed that CD4+/CD8+ T cells (28.9 % and 14.3 %, respectively) and macrophages(M2) accounted for the majority of cells in PBC and BCBM, respectively. Further analysis of the classification of CAFs showed that apCAFs were significantly higher in PBC.

Conclusions

This study presents the landscape of BCBM with hub gene searching and single-cell analysis. Showing the difference in the tumor/immune microenvironment of PBC and BCBM, would be beneficial to explore immunotherapy and targeted therapy for BCBM.

Spatial multiomics reveals a subpopulation of fibroblasts associated with cancer stemness in human hepatocellular carcinoma

BACKGROUND

Cancer-associated fibroblasts (CAFs) are the prominent cell type in the tumor microenvironment (TME), and CAF subsets have been identified in various tumors. However, how CAFs spatially coordinate other cell populations within the liver TME to promote cancer progression remains unclear.

METHODS

We combined multi-region proteomics (6 patients, 24 samples), 10X Genomics Visium spatial transcriptomics (11 patients, 25 samples), and multiplexed imaging (92 patients, 264 samples) technologies to decipher the expression heterogeneity, functional diversity, spatial distribution, colocalization, and interaction of fibroblasts. The newly identified CAF subpopulation was validated by cells isolated from 5 liver cancer patients and in vitro functional assays.

RESULTS

We identified a liver CAF subpopulation, marked by the expression of COL1A2, COL4A1, COL4A2, CTGF, and FSTL1, and named F5-CAF. F5-CAF is preferentially located within and around tumor nests and colocalizes with cancer cells with higher stemness in hepatocellular carcinoma (HCC). Multiplexed staining of 92 patients and the bulk transcriptome of 371 patients demonstrated that the abundance of F5-CAFs in HCC was associated with a worse prognosis. Further in vitro experiments showed that F5-CAFs isolated from liver cancer patients can promote the proliferation and stemness of HCC cells.

CONCLUSIONS

We identified a CAF subpopulation F5-CAF in liver cancer, which is associated with cancer stemness and unfavorable prognosis. Our results provide potential mechanisms by which the CAF subset in the TME promotes the development of liver cancer by supporting the survival of cancer stem cells.

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

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

Unraveling the metastatic niche in breast cancer bone metastasis through single-cell RNA sequencing

PURPOSE

Breast cancer (BRCA) is characterized by a unique metastatic pattern, often presenting with bone metastasis (BoM), posing significant clinical challenges. Through the study of the immune microenvironment in BRCA BoM offer perspectives for therapeutic interventions targeting this specific metastatic manifestation of BRCA.

METHODS

This study employs single-cell RNA sequencing and TCGA data analysis to comprehensively compare primary tumors (PT), lymph node metastasis (LN), and BoM.

RESULTS AND CONCLUSIONS

Our investigation identifies a metastatic niche in BoM marked by an increased abundance of cancer-associated fibroblasts (CAFs) and reduced immune cell presence. A distinct subtype (State 1) of BRCA BoM cells associated with adverse prognosis is identified. State 1, displaying heightened stemness traits, may represent an initiation phase for BoM in BRCA. Complex cell communications involving tumor, stromal, and immune cells are revealed. Interactions of FN1, SPP1, and MDK correlate with elevated immune cells in BoM. CD46, MDK, and PTN interactions drive myofibroblast activation and proliferation, contributing to tissue remodeling. Additionally, MDK, PTN, and FN1 interactions influence FAP+ CAF activation, impacting cell adhesion and migration in BoM. These insights deepen our understanding of the metastatic niche in breast cancer BoM.

Cancer-associated fibroblasts-secreted exosomal miR-92a-3p promotes tumor growth and stemness in hepatocellular carcinoma through activation of Wnt/β-catenin signaling pathway by suppressing AXIN1

Cancer-associated fibroblasts (CAFs) are a major cellular component in the tumor microenvironment and have been shown to exhibit protumorigenic effects in hepatocellular carcinoma (HCC). This study aimed to delve into the mechanisms underlying the tumor-promoting effects of CAFs in HCC. Small RNA sequencing was conducted to screen differential expressed microRNAs in exosomes derived from CAFs and normal fibroblasts (NFs). The miR-92a-3p expression was then measured using reverse transcriptase quantitative real-time PCR in CAFs, NFs, CAFs-derived exosomes (CAFs-Exo), and NF-derived exosomes (NFs-Exo). Compared to NFs or NF-Exo, CAFs and CAFs-Exo significantly promoted HCC cell proliferation, migration, and stemness. Additionally, compared to NFs or NF-Exo, miR-92a-3p level was notably higher in CAFs and CAFs-Exo, respectively. Exosomal miR-92a-3p was found to enhance HCC cell proliferation, migration, and stemness. Meanwhile, AXIN1 was targeted by miR-92a-3p. Exosomal miR-92a-3p could activate β-catenin/CD44 signaling in HCC cells by inhibiting AXIN1 messenger RNA. Furthermore, in vivo studies verified that exosomal miR-92a-3p notably promoted tumor growth and stemness through targeting AXIN1/β-catenin axis. Collectively, CAFs secreted exosomal miR-92a-3p was capable of promoting growth and stemness in HCC through activation of Wnt/β-catenin signaling pathway by suppressing AXIN1. Therefore, targeting CAFs-derived miR-92a-3p may be a potential strategy for treating HCC.

Exposure of benzo[a]pyrene induces HCC exosome-circular RNA to activate lung fibroblasts and trigger organotropic metastasis

BACKGROUND

Benzo[a]pyrene (B[a]P), a carcinogen pollutant produced by combustion processes, is present in the western diet with grilled meats. Chronic exposure of B[a]P in hepatocellular carcinoma (HCC) cells promotes metastasis rather than primary proliferation, implying an unknown mechanism of B[a]P-induced malignancy. Given that exosomes carry bioactive molecules to distant sites, we investigated whether and how exosomes mediate cancer-stroma communications for a toxicologically associated microenvironment.

METHOD

Exosomes were isolated from B[a]P stimulated BEL7404 HCC cells (7404-100Bap Exo) at an environmental relevant dose (100 nmol/L). Lung pre-education animal model was prepared via injection of exosomes and cytokines. The inflammatory genes of educated lungs were evaluated using quantitative reverse transcription PCR array. HCC LM3 cells transfected with firefly luciferase were next injected to monitor tumor burdens and organotropic metastasis. Profile of B[a]P-exposed exosomes were determined by ceRNA microarray. Interactions between circular RNA (circRNA) and microRNAs (miRNAs) were detected using RNA pull-down in target lung fibroblasts. Fluorescence in situ hybridization and RNA immunoprecipitation assay was used to evaluate the "on-off" interaction of circRNA-miRNA pairs. We further developed an adeno-associated virus inhalation model to examine mRNA expression specific in lung, thereby exploring the mRNA targets of B[a]P induced circRNA-miRNA cascade.

RESULTS

Lung fibroblasts exert activation phenotypes, including focal adhesion and motility were altered by 7404-100Bap Exo. In the exosome-educated in vivo model, fibrosis factors and pro-inflammatory molecules of are up-regulated when injected with exosomes. Compared to non-exposed 7404 cells, circ_0011496 was up-regulated following B[a]P treatment and was mainly packaged into 7404-100Bap Exo. Exosomal circ_0011496 were delivered and competitively bound to miR-486-5p in recipient fibroblasts. The down-regulation of miR-486-5p converted fibroblast to cancer-associated fibroblast via regulating the downstream of Twinfilin-1 (TWF1) and matrix metalloproteinase-9 (MMP9) cascade. Additionally, increased TWF1, specifically in exosomal circ_0011496 educated lungs, could promote cancer-stroma crosstalk via activating vascular endothelial growth factor (VEGF). These modulated fibroblasts promoted endothelial cells angiogenesis and recruited primary HCC cells invasion, as a consequence of a pre-metastatic niche formation.

CONCLUSION

We demonstrated that B[a]P-induced tumor exosomes can deliver circ_0011496 to activate miR-486-5p/TWF1/MMP9 cascade in the lung fibroblasts, generating a feedback loop that promoted HCC metastasis.

A Review of CAR-T Combination Therapies for Treatment of Gynecological Cancers

CAR-T cell therapy offers a promising way for prolonged cancer remission, specifically in the case of blood cancers. However, its application in the treatment of solid tumors still faces many limitations. This review paper provides a comprehensive overview of the challenges and strategies associated with CAR-T cell therapy for solid tumors, with a focus on gynecological cancer. This study discusses the limitations of CAR-T therapy for solid tumor treatment, such as T cell exhaustion, stromal barrier, and antigen shedding. Additionally, it addresses possible approaches to increase CAR-T efficacy in solid tumors, including combination therapies with checkpoint inhibitors and chemotherapy, as well as the novel approach of combining CAR-T with oncolytic virotherapy. Given the lack of comprehensive research on CAR-T combination therapies for treating gynecological cancers, this review aims to provide insights into the current landscape of combination therapies for solid tumors and highlight the potential of such an approach in gynecology.

Burning down the house: Pyroptosis in the tumor microenvironment of hepatocellular carcinoma

A high mortality rate makes hepatocellular carcinoma (HCC) a difficult cancer to treat. When surgery is not possible, liver cancer patients are treated with chemotherapy. However, HCC management and treatment are difficult. Sorafenib, which is a first-line treatment for hepatocellular carcinoma, initially slows disease progression. However, sorafenib resistance limits patient survival. Recent studies have linked HCC to programmed cell death, which has increased researcher interest in therapies targeting cell death. Pyroptosis, which is an inflammatory mode of programmed cell death, may be targeted to treat HCC. Pyroptosis pathways, executors, and effects are examined in this paper. This review summarizes how pyroptosis affects the tumor microenvironment (TME) in HCC, including the role of cytokines such as IL-1β and IL-18 in regulating immune responses. The use of chemotherapies and their ability to induce cancer cell pyroptosis as alternative treatments and combining them with other drugs to reduce side effects is also discussed. In conclusion, we highlight the potential of inducing pyroptosis to treat HCC and suggest ways to improve patient outcomes. Studies on cancer cell pyroptosis may lead to new HCC treatments.

A study on combination of non-ablative local RFA with PD-1 and angiogenesis blocking to prolong survival through improvement of immune microenvironment in advanced Hepatocellular Carcinoma

Radiofrequency ablation (RFA), an effective local treatment method for early-stage Hepatocellular Carcinoma (HCC), combined with PD-1 blocking and anti-angiogenic therapy is being extensively explored in advanced HCC, however, the definite results and underlying mechanisms still remain to be elucidated. Therefore, whether non-ablative RFA-based combined therapy can play a synergistic anti-tumor effect through improving tumor immune microenvironment was investigated by us in HCC mouse models. Our results showed that non-ablative RFA could regulate multilayered immunity, such as inducing immunogenic death of tumor cells, upregulating the secretion of inflammatory cytokines, mainly IFN-γ, TNF-α, and IL-10, and subsequently promoting the infiltration of CD8 + T cells. As a result, a significant synergistic anti-tumor effect was demonstrated in the combination therapy group. Similarly, in the real-world setting, non-curative RFA combined with PD-1 blocking and Lenvatinib for 12 patients with Barcelona Clinic Liver Cancer (BCLC) stage C achieve promising results, with 6.9 months (95 % CI: 3.23-15.73) median progression-free survival (mPFS) and 12.7 months (95 % CI: 7.40-19.73) median overall survival (mOS). The common treatment-related adverse reactions were pneumonia and thyroiditis with low prevalence, both less than grade 3 and manageable by symptomatic treatment. Summarily, local non-ablative RFA should be a clinically preferred strategy in combination with PD-1 blocking and anti-angiogenic therapy, because this more flexible scheme abandons its historical concept of tumor eradication, but fully utilizes the immune regulatory function by inducing immunogenic tumor death and has higher-level of safety. Therefore, this is a two-pronged and highly balanced approach to achieved favorable treatment outcomes, while conclusive evidence is still pending, it can be attempted in the real world anyway.

Spatiotemporal heterogeneity of LMOD1 expression summarizes two modes of cell communication in colorectal cancer

Cellular communication (CC) influences tumor development by mediating intercellular junctions between cells. However, the role and underlying mechanisms of CC in malignant transformation remain unknown. Here, we investigated the spatiotemporal heterogeneity of CC molecular expression during malignant transformation. It was found that although both tight junctions (TJs) and gap junctions (GJs) were involved in maintaining the tumor microenvironment (TME), they exhibited opposite characteristics. Mechanistically, for epithelial cells (parenchymal component), the expression of TJ molecules consistently decreased during normal-cancer transformation and is a potential oncogenic factor. For fibroblasts (mesenchymal component), the expression of GJs consistently increased during normal-cancer transformation and is a potential oncogenic factor. In addition, the molecular profiles of TJs and GJs were used to stratify colorectal cancer (CRC) patients, where subtypes characterized by high GJ levels and low TJ levels exhibited enhanced mesenchymal signals. Importantly, we propose that leiomodin 1 (LMOD1) is biphasic, with features of both TJs and GJs. LMOD1 not only promotes the activation of cancer-associated fibroblasts (CAFs) but also inhibits the Epithelial-mesenchymal transition (EMT) program in cancer cells. In conclusion, these findings demonstrate the molecular heterogeneity of CC and provide new insights into further understanding of TME heterogeneity.

Cancer stem cell-immune cell crosstalk in the tumor microenvironment for liver cancer progression

Crosstalk between cancer cells and the immune microenvironment is determinant for liver cancer progression. A tumor subpopulation called liver cancer stem cells (CSCs) significantly accounts for the initiation, metastasis, therapeutic resistance, and recurrence of liver cancer. Emerging evidence demonstrates that the interaction between liver CSCs and immune cells plays a crucial role in shaping an immunosuppressive microenvironment and determining immunotherapy responses. This review sheds light on the bidirectional crosstalk between liver CSCs and immune cells for liver cancer progression, as well as the underlying molecular mechanisms after presenting an overview of liver CSCs characteristic and their microenvironment. Finally, we discuss the potential application of liver CSCs-targeted immunotherapy for liver cancer treatment.

Impact of STAT-signaling pathway on cancer-associated fibroblasts in colorectal cancer and its role in immunosuppression

Colorectal cancer (CRC) remains one of the most commonly diagnosed and deadliest types of cancer worldwide. CRC displays a desmoplastic reaction (DR) that has been inversely associated with poor prognosis; less DR is associated with a better prognosis. This reaction generates excessive connective tissue, in which cancer-associated fibroblasts (CAFs) are critical cells that form a part of the tumor microenvironment. CAFs are directly involved in tumorigenesis through different mechanisms. However, their role in immunosuppression in CRC is not well understood, and the precise role of signal transducers and activators of transcription (STATs) in mediating CAF activity in CRC remains unclear. Among the myriad chemical and biological factors that affect CAFs, different cytokines mediate their function by activating STAT signaling pathways. Thus, the harmful effects of CAFs in favoring tumor growth and invasion may be modulated using STAT inhibitors. Here, we analyze the impact of different STATs on CAF activity and their immunoregulatory role.

DNA of Neutrophil Extracellular Traps Binds TMCO6 to Impair CD8+ T-cell Immunity in Hepatocellular Carcinoma

Neutrophil extracellular traps (NET), formed by the extracellular release of decondensed chromatin and granules, have been shown to promote tumor progression and metastasis. Tumor-associated neutrophils in hepatocellular carcinoma (HCC) are prone to NET formation, highlighting the need for a more comprehensive understanding of the mechanisms of action of NETs in liver cancer. Here, we showed that DNA of NETs (NET-DNA) binds transmembrane and coiled-coil domains 6 (TMCO6) on CD8+ T cells to impair antitumor immunity and thereby promote HCC progression. TGFβ1 induced NET formation, which recruited CD8+ T cells. Binding to NET-DNA inhibited CD8+ T cells function while increasing apoptosis and TGFβ1 secretion, forming a positive feedback loop to further stimulate NET formation and immunosuppression. Mechanistically, the N-terminus of TMCO6 interacted with NET-DNA and suppressed T-cell receptor signaling and NFκB p65 nuclear translocation. Blocking NET formation by inhibiting PAD4 induced potent antitumor effects in wild-type mice but not TMCO6-/- mice. In clinical samples, CD8+ T cells expressing TMCO6 had an exhausted phenotype. TGFβ1 signaling inhibition or TMCO6 deficiency combined with anti-PD-1 abolished NET-driven HCC progression in vivo. Collectively, this study unveils the role of NET-DNA in impairing CD8+ T-cell immunity by binding TMCO6 and identifies targeting this axis as an immunotherapeutic strategy for blocking HCC progression.

SIGNIFICANCE

TMCO6 is a receptor for DNA of NETs that mediates CD8+ T-cell dysfunction in HCC, indicating that the NET-TMCO6 axis is a promising target for overcoming immunosuppression in liver cancer.

Hepatocellular Carcinoma and the Multifaceted Relationship with Its Microenvironment: Attacking the Hepatocellular Carcinoma Defensive Fortress

Hepatocellular carcinoma is a malignant tumor that originates from hepatocytes in an inflammatory substrate due to different degrees of liver fibrosis up to cirrhosis. In recent years, there has been growing interest in the role played by the complex interrelationship between hepatocellular carcinoma and its microenvironment, capable of influencing tumourigenesis, neoplastic growth, and its progression or even inhibition. The microenvironment is made up of an intricate network of mesenchymal cells, immune system cells, extracellular matrix, and growth factors, as well as proinflammatory cytokines and translocated bacterial products coming from the intestinal microenvironment via the enterohepatic circulation. The aim of this paper is to review the role of the HCC microenvironment and describe the possible implications in the choice of the most appropriate therapeutic scheme in the prediction of tumor response or resistance to currently applied treatments and in the possible development of future therapeutic perspectives, in order to circumvent resistance and break down the tumor's defensive fort.

CXCL9 Overexpression Predicts Better HCC Response to Anti-PD-1 Therapy and Promotes N1 Polarization of Neutrophils

Background

Anti-programmed death-1 (PD1) antibodies have changed the treatment landscape for hepatocellular carcinoma (HCC) and exhibit promising treatment efficacy. However, the majority of HCCs still do not respond to anti-PD-1 therapy.

Methods

We analyzed the expression of CXCL9 in blood samples from patients who received anti-PD-1 therapy and evaluated its correlation with clinicopathological characteristics and treatment outcomes. Based on the results of Cox regression analysis, a nomogram was established for predicting HCC response to anti-PD-1 therapy. qRT‒PCR and multiple immunofluorescence assays were utilized to analyze the proportions of N1-type neutrophils in vitro and in tumor samples, respectively.

Results

The nomogram showed good predictive efficacy in the training and validation cohorts and may be useful for guiding clinical treatment of HCC patients. We also found that HCC cell-derived CXCL9 promoted N1 polarization of neutrophils in vitro and that AMG487, a specific CXCR3 inhibitor, significantly blocked this process. Moreover, multiple immunofluorescence (mIF) showed that patients with higher serum CXCL9 levels had greater infiltration of the N1 phenotype of tumor-associated neutrophils (TANs).

Conclusion

Our study highlights the critical role of CXCL9 as an effective biomarker of immunotherapy efficacy and in promoting the polarization of N1-type neutrophils; thus, targeting the CXCL9-CXCR3 axis could represent a novel pharmaceutical strategy to enhance immunotherapy for HCC.

Hallmarks of cancer stemness

Cancer stemness is recognized as a key component of tumor development. Previously coined "cancer stem cells" (CSCs) and believed to be a rare population with rigid hierarchical organization, there is good evidence to suggest that these cells exhibit a plastic cellular state influenced by dynamic CSC-niche interplay. This revelation underscores the need to reevaluate the hallmarks of cancer stemness. Herein, we summarize the techniques used to identify and characterize the state of these cells and discuss their defining and emerging hallmarks, along with their enabling and associated features. We also highlight potential future directions in this field of research.

Immunosuppressive tumor microenvironment and immunotherapy of hepatocellular carcinoma: current status and prospectives

Hepatocellular carcinoma (HCC) is a major health concern worldwide, with limited therapeutic options and poor prognosis. In recent years, immunotherapies such as immune checkpoint inhibitors (ICIs) have made great progress in the systemic treatment of HCC. The combination treatments based on ICIs have been the major trend in this area. Recently, dual immune checkpoint blockade with durvalumab plus tremelimumab has also emerged as an effective treatment for advanced HCC. However, the majority of HCC patients obtain limited benefits. Understanding the immunological rationale and exploring novel ways to improve the efficacy of immunotherapy has drawn much attention. In this review, we summarize the latest progress in this area, the ongoing clinical trials of immune-based combination therapies, as well as novel immunotherapy strategies such as chimeric antigen receptor T cells, personalized neoantigen vaccines, oncolytic viruses, and bispecific antibodies.

Cancer-associated fibroblasts promote gastric cancer cell proliferation by paracrine FGF2-driven ribosome biogenesis

The cancer-associated fibroblast (CAF)-derived secretome plays critical roles in tumor progression by remodelling tumor microenvironment. Tumorigenesis is accompanied by the transformation of normal fibroblasts (NF) into CAF, leading to significant changes in their secretome. This work aims to identify the differential components of secretome between NFs and CAFs and reveal their functions in gastric cancer (GC). Firstly, our molecular typing studies and immune infiltration analysis showed that CAF infiltration level was increased and showed a significant association with clinical characteristics and poor prognosis of GC patients. Secondly, RNA-seq analysis revealed that a total of 1531 genes showed significant expression changes between NF and CAF. According to the annotation of the Human Protein Atlas (HPA) database, 147 genes encode secreted proteins, including FGF2. Particularly, the cell co-culture and RNA sequencing studies confirmed that exogenous recombinant FGF2 protein treatment promoted GC cell proliferation by enhancing ribosome biogenesis. The rescue assay showed that CAF-secreted FGF2 protein promotes GC cell growth and proliferation in a FGFR1-dependent manner. Our finding provides evidence that targeting blockade of CAF-derived FGF2 protein might be a promising treatment for GC.

Predictive value of a stemness-based classifier for prognosis and immunotherapy response of hepatocellular carcinoma based on bioinformatics and machine-learning strategies

Objective

Significant advancements have been made in hepatocellular carcinoma (HCC) therapeutics, such as immunotherapy for treating patients with HCC. However, there is a lack of reliable biomarkers for predicting the response of patients to therapy, which continues to be challenging. Cancer stem cells (CSCs) are involved in the oncogenesis, drug resistance, and invasion, as well as metastasis of HCC cells. Therefore, in this study, we aimed to create an mRNA expression-based stemness index (mRNAsi) model to predict the response of patients with HCC to immunotherapy.

Methods

We retrieved gene expression and clinical data of patients with HCC from the GSE14520 dataset and the Cancer Genome Atlas (TCGA) database. Next, we used the "one-class logistic regression (OCLR)" algorithm to obtain the mRNAsi of patients with HCC. We performed "unsupervised consensus clustering" to classify patients with HCC based on the mRNAsi scores and stemness subtypes. The relationships between the mRNAsi model, clinicopathological features, and genetic profiles of patients were compared using various bioinformatic methods. We screened for differentially expressed genes to establish a stemness-based classifier for predicting the patient's prognosis. Next, we determined the effect of risk scores on the tumor immune microenvironment (TIME) and the response of patients to immune checkpoint blockade (ICB). Finally, we used qRT-PCR to investigate gene expression in patients with HCC.

Results

We screened CSC-related genes using various bioinformatics tools in patients from the TCGA-LIHC cohort. We constructed a stemness classifier based on a nine-gene (PPARGC1A, FTCD, CFHR3, MAGEA6, CXCL8, CABYR, EPO, HMMR, and UCK2) signature for predicting the patient's prognosis and response to ICBs. Further, the model was validated in an independent GSE14520 dataset and performed well. Our model could predict the status of TIME, immunogenomic expressions, congenic pathway, and response to chemotherapy drugs. Furthermore, a significant increase in the proportion of infiltrating macrophages, Treg cells, and immune checkpoints was observed in patients in the high-risk group. In addition, tumor cells in patients with high mRNAsi scores could escape immune surveillance. Finally, we observed that the constructed model had a good expression in the clinical samples. The HCC tumor size and UCK2 genes expression were significantly alleviated and decreased, respectively, by treatments of anti-PD1 antibody. We also found knockdown UCK2 changed expressions of immune genes in HCC cell lines.

Conclusion

The novel stemness-related model could predict the prognosis of patients and aid in creating personalized immuno- and targeted therapy for patients in HCC.

PDGFRα+ITGA11+ fibroblasts foster early-stage cancer lymphovascular invasion and lymphatic metastasis via ITGA11-SELE interplay

Cancer-associated fibroblasts (CAFs) exhibit considerable heterogeneity in advanced cancers; however, the functional annotation and mechanism of CAFs in early-stage cancers remain elusive. Utilizing single-cell RNA sequencing and spatial transcriptomic, we identify a previously unknown PDGFRα+ITGA11+ CAF subset in early-stage bladder cancer (BCa). Multicenter clinical analysis of a 910-case cohort confirms that PDGFRα+ITGA11+ CAFs are associated with lymphovascular invasion (LVI) and poor prognosis in early-stage BCa. These CAFs facilitate LVI and lymph node (LN) metastasis in early-stage BCa, as evidenced in a PDGFRα+ITGA11+ CAFs-specific deficient mouse model. Mechanistically, PDGFRα+ITGA11+ CAFs promote lymphangiogenesis via recognizing ITGA11 surface receptor SELE on lymphatic endothelial cells to activate SRC-p-VEGFR3-MAPK pathway. Further, CHI3L1 from PDGFRα+ITGA11+ CAFs aligns the surrounding matrix to assist cancer cell intravasation, fostering early-stage BCa LVI and LN metastasis. Collectively, our study reveals the crucial role of PDGFRα+ITGA11+ CAFs in shaping metastatic landscape, informing the treatment of early-stage BCa LVI.

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.

Exosomal ncRNAs: Multifunctional contributors to the immunosuppressive tumor microenvironment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a malignant liver cancer characterized by aggressive progression, unfavorable prognosis, and an increasing global health burden. Therapies that precisely target immunological checkpoints and immune cells have gained significant attention as possible therapeutics in recent years. In truth, the efficacy of immunotherapy is heavily contingent upon the tumor microenvironment (TME). Recent studies have indicated that exosomes serve as a sophisticated means of communication among biomolecules, executing an essential part in the TME of immune suppression. Exosomal non-coding RNAs (ncRNAs) can induce the activation of tumor cells and immunosuppressive immune cells that suppress the immune system, such as cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), tumor-associated neutrophils (TANs), CD+8 T cells, regulatory T cells (Tregs), and regulatory B cells (Bregs). This cell-cell crosstalk triggered by exosomal ncRNAs promotes tumor proliferation and metastasis, angiogenesis, malignant phenotype transformation, and drug resistance. Hence, it is imperative to comprehend how exosomal ncRNAs regulate tumor cells or immune cells within the TME to devise more comprehensive and productive immunotherapy programs. This study discusses the features of exosomal ncRNAs in HCC and how the activation of the exosomes redefines the tumor's immunosuppressive microenvironment, hence facilitating the advancement of HCC. Furthermore, we also explored the potential of exosomal ncRNAs as a viable biological target or natural vehicle for HCC therapy.

The CLCF1-CNTFR axis drives an immunosuppressive tumor microenvironment and blockade enhances the effects of established cancer therapies

Tumors comprise a complex ecosystem consisting of many cell types that communicate through secreted factors. Targeting these intercellular signaling networks remains an important challenge in cancer research. Cardiotrophin-like cytokine factor 1 (CLCF1) is an interleukin-6 (IL-6) family member secreted by cancer-associated fibroblasts (CAFs) that binds to ciliary neurotrophic factor receptor (CNTFR), promoting tumor growth in lung and liver cancer1,2. A high-affinity soluble receptor (eCNTFR-Fc) that sequesters CLCF1 has anti-oncogenic effects3. However, the role of CLCF1 in mediating cell-cell interactions in cancer has remained unclear. We demonstrate that eCNTFR-Fc has widespread effects on both tumor cells and the tumor microenvironment and can sensitize cancer cells to KRAS inhibitors or immune checkpoint blockade. After three weeks of treatment with eCNTFR-Fc, there is a shift from an immunosuppressive to an immunostimulatory macrophage phenotype as well as an increase in activated T, NKT, and NK cells. Combination of eCNTFR-Fc and αPD1 was significantly more effective than single-agent therapy in a syngeneic allograft model, and eCNTFR-Fc sensitizes tumor cells to αPD1 in a non-responsive GEM model of lung adenocarcinoma. These data suggest that combining eCNTFR-Fc with KRAS inhibition or with αPD1 is a novel therapeutic strategy for lung cancer and potentially other cancers in which these therapies have been used but to date with only modest effect. Overall, we demonstrate the potential of cancer therapies that target cytokines to alter the immune microenvironment.

Nano-Drug Delivery Systems Targeting CAFs: A Promising Treatment for Pancreatic Cancer

Currently, pancreatic cancer (PC) is one of the most lethal malignant tumors. PC is typically diagnosed at a late stage, exhibits a poor response to conventional treatment, and has a bleak prognosis. Unfortunately, PC's survival rate has not significantly improved since the 1960s. Cancer-associated fibroblasts (CAFs) are a key component of the pancreatic tumor microenvironment (TME). They play a vital role in maintaining the extracellular matrix and facilitating the intricate communication between cancer cells and infiltrated immune cells. Exploring therapeutic approaches targeting CAFs may reverse the current landscape of PC therapy. In recent years, nano-drug delivery systems have evolved rapidly and have been able to accurately target and precisely release drugs with little or no toxicity to the whole body. In this review, we will comprehensively discuss the origin, heterogeneity, potential targets, and recent advances in the nano-drug delivery system of CAFs in PC. We will also propose a novel integrated treatment regimen that utilizes a nano-drug delivery system to target CAFs in PC, combined with radiotherapy and immunotherapy. Additionally, we will address the challenges that this regimen currently faces.

SERPINE2 promotes liver cancer metastasis by inhibiting c-Cbl-mediated EGFR ubiquitination and degradation

BACKGROUND

Liver cancer is a malignancy with high morbidity and mortality rates. Serpin family E member 2 (SERPINE2) has been reported to play a key role in the metastasis of many tumors. In this study, we aimed to investigate the potential mechanism of SERPINE2 in liver cancer metastasis.

METHODS

The Cancer Genome Atlas database (TCGA), including DNA methylation and transcriptome sequencing data, was utilized to identify the crucial oncogene associated with DNA methylation and cancer progression in liver cancer. Data from the TCGA and RNA sequencing for 94 pairs of liver cancer tissues were used to explore the correlation between SERPINE2 expression and clinical parameters of patients. DNA methylation sequencing was used to detect the DNA methylation levels in liver cancer tissues and cells. RNA sequencing, cytokine assays, immunoprecipitation (IP) and mass spectrometry (MS) assays, protein stability assays, and ubiquitination assays were performed to explore the regulatory mechanism of SERPINE2 in liver cancer metastasis. Patient-derived xenografts and tumor organoid models were established to determine the role of SERPINE2 in the treatment of liver cancer using sorafenib.

RESULTS

Based on the public database screening, SERPINE2 was identified as a tumor promoter regulated by DNA methylation. SERPINE2 expression was significantly higher in liver cancer tissues and was associated with the dismal prognosis in patients with liver cancer. SERPINE2 promoted liver cancer metastasis by enhancing cell pseudopodia formation, cell adhesion, cancer-associated fibroblast activation, extracellular matrix remodeling, and angiogenesis. IP/MS assays confirmed that SERPINE2 activated epidermal growth factor receptor (EGFR) and its downstream signaling pathways by interacting with EGFR. Mechanistically, SERPINE2 inhibited EGFR ubiquitination and maintained its protein stability by competing with the E3 ubiquitin ligase, c-Cbl. Additionally, EGFR was activated in liver cancer cells after sorafenib treatment, and SERPINE2 knockdown-induced EGFR downregulation significantly enhanced the therapeutic efficacy of sorafenib against liver cancer. Furthermore, we found that SERPINE2 knockdown also had a sensitizing effect on lenvatinib treatment.

CONCLUSIONS

SERPINE2 promoted liver cancer metastasis by preventing EGFR degradation via c-Cbl-mediated ubiquitination, suggesting that inhibition of the SERPINE2-EGFR axis may be a potential target for liver cancer treatment.

Targeting neutrophils: Mechanism and advances in cancer therapy

BACKGROUND

Cancer is a thorny problem which cannot be conquered by mankind at present and recent researchers have put their focus on tumor microenviroment. Neutrophils, the prominent leukocytes in peripheral blood that accumulate in tumours, serves as frontline cells in response to tumour progression owing to the rapid development of micro biotechnology. Hence, targeted therapy with these neutrophils has made targeting treatment a promising field in cancer therapy.

MAIN BODY

We broadly summarise some studies on the phenotypes and functions of tumour-associated neutrophils as well as the unique web-like products of neutrophils that play a role in cancer progression-neutrophil extracellular traps-and the interactions between neutrophils and the tumour microenvironment. Moreover, several targeted neutrophils therapeutic studies have made some progress and provided potential strategies for the treatment of cancer.

CONCLUSION

This review aims to offer a holistic perspective on therapeutic interventions targeting neutrophils to further inspire more researches on cancer therapies.

Tumor cell stemness in gastrointestinal cancer: regulation and targeted therapy

The cancer stem cells are a rare group of self-renewable cancer cells capable of the initiation, progression, metastasis and recurrence of tumors, and also a key contributor to the therapeutic resistance. Thus, understanding the molecular mechanism of tumor stemness regulation, especially in the gastrointestinal (GI) cancers, is of great importance for targeting CSC and designing novel therapeutic strategies. This review aims to elucidate current advancements in the understanding of CSC regulation, including CSC biomarkers, signaling pathways, and non-coding RNAs. We will also provide a comprehensive view on how the tumor microenvironment (TME) display an overall tumor-promoting effect, including the recruitment and impact of cancer-associated fibroblasts (CAFs), the establishment of an immunosuppressive milieu, and the induction of angiogenesis and hypoxia. Lastly, this review consolidates mainstream novel therapeutic interventions targeting CSC stemness regulation.

Mapping the core senescence phenotype of primary human colon fibroblasts

Advanced age is the largest risk factor for many diseases and several types of cancer, including colorectal cancer (CRC). Senescent cells are known to accumulate with age in various tissues, where they can modulate the surrounding tissue microenvironment through their senescence associated secretory phenotype (SASP). Recently, we showed that there is an increased number of senescent cells in the colons of CRC patients and demonstrated that senescent fibroblasts and their SASP create microniches in the colon that are conducive to CRC onset and progression. However, the composition of the SASP is heterogenous and cell-specific, and the precise senescence profile of colon fibroblasts has not been well-defined. To generate a SASP atlas of human colon fibroblasts, we induced senescence in primary human colon fibroblasts using various in vitro methods and assessed the resulting transcriptome. Using RNASequencing and further validation by quantitative RT-PCR and Luminex assays, we define and validate a 'core senescent profile' that might play a significant role in shaping the colon microenvironment. We also performed KEGG analysis and GO analyses to identify key pathways and biological processes that are differentially regulated in colon fibroblast senescence. These studies provide insights into potential driver proteins involved in senescence-associated diseases, like CRC, which may lead to therapies to improve overall health in the elderly and to prevent CRC.

Intrahepatic IgA complex induces polarization of cancer-associated fibroblasts to matrix phenotypes in the tumor microenvironment of HCC

BACKGROUND AND AIMS

Cancer-associated fibroblasts (CAFs) play key roles in the tumor microenvironment. IgA contributes to inflammation and dismantling antitumor immunity in the human liver. In this study, we aimed to elucidate the effects of the IgA complex on CAFs in Pil Soo Sung the tumor microenvironment of HCC.

APPROACH AND RESULTS

CAF dynamics in HCC tumor microenvironment were analyzed through single-cell RNA sequencing of HCC samples. CAFs isolated from 50 HCC samples were treated with mock or serum-derived IgA dimers in vitro. Progression-free survival of patients with advanced HCC treated with atezolizumab and bevacizumab was significantly longer in those with low serum IgA levels ( p <0.05). Single-cell analysis showed that subcluster proportions in the CAF-fibroblast activation protein-α matrix were significantly increased in patients with high serum IgA levels. Flow cytometry revealed a significant increase in the mean fluorescence intensity of fibroblast activation protein in the CD68 + cells from patients with high serum IgA levels ( p <0.001). We confirmed CD71 (IgA receptor) expression in CAFs, and IgA-treated CAFs exhibited higher programmed death-ligand 1 expression levels than those in mock-treated CAFs ( p <0.05). Coculture with CAFs attenuated the cytotoxic function of activated CD8 + T cells. Interestingly, activated CD8 + T cells cocultured with IgA-treated CAFs exhibited increased programmed death-1 expression levels than those cocultured with mock-treated CAFs ( p <0.05).

CONCLUSIONS

Intrahepatic IgA induced polarization of HCC-CAFs into more malignant matrix phenotypes and attenuates cytotoxic T-cell function. Our study highlighted their potential roles in tumor progression and immune suppression.

Lipopolysaccharide-Educated Cancer-Associated Fibroblasts Facilitate Malignant Progression of Ovarian Cancer Cells via the NF-kB/IL-6/JAK2 Signal Transduction

Gram-negative bacteria increase in ovarian cancer (OC) tissues, but its association with OC progression remains largely unknown. The present study aimed to investigate whether and how cancer-associated fibroblasts (CAFs) pretreated by the main components of bacterial outer membrane lipopolysaccharide (LPS) influence the malignancy of OC cells. Specifically, the culture medium of LPS-preconditioned CAFs (LPS-CM) further accelerated cell proliferation, colony formation and tumorigenesis of OC cells SKOV3 and HEY A8, compared with culture medium of CAFs. Next, we found that LPS pretreatment activated the nuclear factor-kappa B (NF-kB) pathway in CAFs to secret cytokines, including interleukin 1β (IL-1β), interleukin 6 (IL-6), vascular endothelial growth factor (VEGF), etc. Neutralization of IL-6 in LPS-CM abolished the promoting effect of LPS-CM on cell proliferation, survival and epithelial-mesenchymal transition (EMT) in SKOV3 and HEY A8 cells. Mechanistically, LPS-CM activated the Janus kinases 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway, while application with JAK2 inhibitor also reversed the promoting effect of LPS-CM on malignancy of OC cells. In summary, LPS-pretreated CAFs IL-6-dependently accelerate OC progression via activating the JAK2/STAT3 signal pathway, which enriches our understanding of the molecular mechanisms underlying ovaries-colonized gram-negative bacteria in OC progression.

Reprogramming of lipid metabolism in the tumor microenvironment: a strategy for tumor immunotherapy

Lipid metabolism in cancer cells has garnered increasing attention in recent decades. Cancer cells thrive in hypoxic conditions, nutrient deficiency, and oxidative stress and cannot be separated from alterations in lipid metabolism. Therefore, cancer cells exhibit increased lipid metabolism, lipid uptake, lipogenesis and storage to adapt to a progressively challenging environment, which contribute to their rapid growth. Lipids aid cancer cell activation. Cancer cells absorb lipids with the help of transporter and translocase proteins to obtain energy. Abnormal levels of a series of lipid synthases contribute to the over-accumulation of lipids in the tumor microenvironment (TME). Lipid reprogramming plays an essential role in the TME. Lipids are closely linked to several immune cells and their phenotypic transformation. The reprogramming of tumor lipid metabolism further promotes immunosuppression, which leads to immune escape. This event significantly affects the progression, treatment, recurrence, and metastasis of cancer. Therefore, the present review describes alterations in the lipid metabolism of immune cells in the TME and examines the connection between lipid metabolism and immunotherapy.

MyD88 in myofibroblasts enhances nonalcoholic fatty liver disease-related hepatocarcinogenesis via promoting macrophage M2 polarization

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver diseases and has emerged as the leading factor in the pathogenesis of hepatocellular carcinoma (HCC). MyD88 contributes to the development of HCC. However, the underlying mechanism by which MyD88 in myofibroblasts regulates NAFLD-associated liver cancer development remains unknown.

RESULTS

Myofibroblast MyD88-deficient (SMAMyD88-/-) mice were protected from diet-induced obesity and developed fewer and smaller liver tumors. MyD88 deficiency in myofibroblasts attenuated macrophage M2 polarization and fat accumulation in HCC tissues. Mechanistically, MyD88 signaling in myofibroblasts enhanced CCL9 secretion, thereby promoting macrophage M2 polarization. This process may depend on the CCR1 receptor and STAT6/ PPARβ pathway. Furthermore, liver tumor growth was attenuated in mice treated with a CCR1 inhibitor. CCLl5 (homologous protein CCL9 in humans) expression was increased in myofibroblasts of HCC and was associated with shorter survival of patients with HCC. Thus, our results indicate that MyD88 in myofibroblasts promotes NAFLD-related HCC progression and may be a promising therapeutic target for HCC treatment.

CONCLUSION

This study demonstrates that MyD88 in myofibroblasts can promote nonalcoholic fatty liver disease-related hepatocarcinogenesis by enhancing macrophage M2 polarization, which might provide a potential molecular therapeutic target for HCC.

The role of stromal cells in epithelial-mesenchymal plasticity and its therapeutic potential

The epithelial-mesenchymal transition (EMT) is a critical tumor invasion and metastasis process. EMT enables tumor cells to migrate, detach from their original location, enter the circulation, circulate within it, and eventually exit from blood arteries to colonize in foreign sites, leading to the development of overt metastases, ultimately resulting in death. EMT is intimately tied to stromal cells around the tumor and is controlled by a range of cytokines secreted by stromal cells. This review summarizes recent research on stromal cell-mediated EMT in tumor invasion and metastasis. We also discuss the effects of various stromal cells on EMT induction and focus on the molecular mechanisms by which several significant stromal cells convert from foes to friends of cancer cells to fuel EMT processes via their secretions in the tumor microenvironment (TME). As a result, a better knowledge of the role of stromal cells in cancer cells' EMT may pave the path to cancer eradication.

CLCF1 inhibits energy expenditure via suppressing brown fat thermogenesis

Brown adipose tissue (BAT) is the main site of nonshivering thermogenesis which plays an important role in thermogenesis and energy metabolism. However, the regulatory factors that inhibit BAT activity remain largely unknown. Here, cardiotrophin-like cytokine factor 1 (CLCF1) is identified as a negative regulator of thermogenesis in BAT. Adenovirus-mediated overexpression of CLCF1 in BAT greatly impairs the thermogenic capacity of BAT and reduces the metabolic rate. Consistently, BAT-specific ablation of CLCF1 enhances the BAT function and energy expenditure under both thermoneutral and cold conditions. Mechanistically, adenylate cyclase 3 (ADCY3) is identified as a downstream target of CLCF1 to mediate its role in regulating thermogenesis. Furthermore, CLCF1 is identified to negatively regulate the PERK-ATF4 signaling axis to modulate the transcriptional activity of ADCY3, which activates the PKA substrate phosphorylation. Moreover, CLCF1 deletion in BAT protects the mice against diet-induced obesity by promoting BAT activation and further attenuating impaired glucose and lipid metabolism. Therefore, our results reveal the essential role of CLCF1 in regulating BAT thermogenesis and suggest that inhibiting CLCF1 signaling might be a potential therapeutic strategy for improving obesity-related metabolic disorders.

Immune Escape Strategies in Head and Neck Cancer: Evade, Resist, Inhibit, Recruit

Head and neck cancers (HNCs) arise from the mucosal lining of the aerodigestive tract and are often associated with alcohol use, tobacco use, and/or human papillomavirus (HPV) infection. Over 600,000 new cases of HNC are diagnosed each year, making it the sixth most common cancer worldwide. Historically, treatments have included surgery, radiation, and chemotherapy, and while these treatments are still the backbone of current therapy, several immunotherapies have recently been approved by the Food and Drug Administration (FDA) for use in HNC. The role of the immune system in tumorigenesis and cancer progression has been explored since the early 20th century, eventually coalescing into the current three-phase model of cancer immunoediting. During each of the three phases-elimination, equilibrium, and escape-cancer cells develop and utilize multiple strategies to either reach or remain in the final phase, escape, at which point the tumor is able to grow and metastasize with little to no detrimental interference from the immune system. In this review, we summarize the many strategies used by HNC to escape the immune system, which include ways to evade immune detection, resist immune cell attacks, inhibit immune cell functions, and recruit pro-tumor immune cells.

Endothelial DGKG promotes tumor angiogenesis and immune evasion in hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is among the most prevalent and lethal cancers worldwide. The tumor microenvironment (TME) contributes to the poor response of patients with HCC to current therapies, while tumor vascular endothelial cells (ECs) are fundamental TME components that significantly contribute to tumor progression. However, the specific functions and mechanisms of tumor vascular ECs in HCC remain unclear.

METHODS

We screened and validated diacylglycerol kinase gamma (DGKG) hyper-expression specifically in HCC tumor vascular ECs. Single-cell RNA-sequencing, cytometry by time-of-flight, and in vitro and in vivo studies were performed to investigate the functions of endothelial DGKG. Multiplexed immunohistochemistry staining and flow cytometry were used to evaluate changes in the TME.

RESULTS

Functionally, endothelial DGKG promotes tumor angiogenesis and immunosuppressive regulatory T-cell differentiation in HCC. Of significance, we found that HIF-1α activates DGKG transcription by directly binding to its promoter region under hypoxia. Upregulated DGKG promotes HCC progression by recruiting ubiquitin specific peptidase 16 to facilitate ZEB2 deubiquitination, which increases TGF-β1 secretion, thus inducing tumor angiogenesis and regulatory T-cell differentiation. Importantly, targeting endothelial DGKG potentiated the efficiency of dual blockade of PD-1 and VEGFR-2.

CONCLUSION

Hypoxia-induced EC-specific DGKG hyper-expression promotes tumor angiogenesis and immune evasion via the ZEB2/TGF-β1 axis, suggesting EC-specific DGKG as a potential therapeutic target for HCC.

IMPACT AND IMPLICATIONS

Here, we reported that hypoxia-induced endothelial cell-specific DGKG hyper-expression promotes angiogenesis and immune evasion in HCC by recruiting USP16 for K48-linked deubiquitination and inducing the subsequent stabilization of ZEB2, leading to increased TGF-β1 secretion. Most importantly, endothelial DGKG inhibition greatly improved the efficacy of the dual combination of anti-VEGFR2 and anti-PD-1 treatment in a mouse HCC model, significantly inhibiting the malignant progression of HCC and improving survival. This preclinical study supports the targeting of endothelial DGKG as a potential strategy for precision HCC treatment.

Glucocorticoid treatment influences prostate cancer cell growth and the tumor microenvironment via altered glucocorticoid receptor signaling in prostate fibroblasts

Despite significant therapeutic advances in recent years, treatment of metastatic prostate cancer (PCa) remains palliative, owing to the inevitable occurrence of drug resistance. There is increasing evidence that epithelial glucocorticoid receptor (GR) signaling and changes in the tumor-microenvironment (TME) play important roles in this process. Since glucocorticoids (GCs) are used as concomitant medications in the course of PCa treatment, it is essential to investigate the impact of GCs on stromal GR signaling in the TME. Therefore, general GR mRNA and protein expression was assessed in radical prostatectomy specimens and metastatic lesions. Elevated stromal GR signaling after GC treatment resulted in altered GR-target gene, soluble protein expression, and in a morphology change of immortalized and primary isolated cancer-associated fibroblasts (CAFs). Subsequently, these changes affected proliferation, colony formation, and 3D-spheroid growth of multiple epithelial PCa cell models. Altered expression of extra-cellular matrix (ECM) and adhesion-related proteins led to an ECM remodeling. Notably, androgen receptor pathway inhibitor treatments did not affect CAF viability. Our findings demonstrate that GC-mediated elevated GR signaling has a major impact on the CAF secretome and the ECM architecture. GC-treated fibroblasts significantly influence epithelial tumor cell growth and must be considered in future therapeutic strategies.