MCT-1/miR-34a/IL-6/IL-6R signaling axis promotes EMT progression, cancer stemness and M2 macrophage polarization in triple-negative breast cancer

Adipocyte regulation of cancer stem cells

Cancer stem cells (CSCs) are a highly tumorigenic subpopulation of the cancer cells within a tumor that drive tumor initiation, progression, and therapy resistance. In general, stem cell niche provides a specific microenvironment in which stem cells are present in an undifferentiated and self-renewable state. CSC niche is a specialized tumor microenvironment for CSCs which provides cues for their maintenance and propagation. However, molecular mechanisms for the CSC-niche interaction remain to be elucidated. We have revealed that adipsin (complement factor D) and its downstream effector hepatocyte growth factor are secreted from adipocytes and enhance the CSC properties in breast cancers in which tumor initiation and progression are constantly associated with the surrounding adipose tissue. Considering that obesity, characterized by excess adipose tissue, is associated with an increased risk of multiple cancers, it is reasonably speculated that adipocyte-CSC interaction is similarly involved in many types of cancers, such as pancreas, colorectal, and ovarian cancers. In this review, various molecular mechanisms by which adipocytes regulate CSCs, including secretion of adipokines, extracellular matrix production, biosynthesis of estrogen, metabolism, and exosome, are discussed. Uncovering the roles of adipocytes in the CSC niche will propose novel strategies to treat cancers, especially those whose progression is linked to obesity.

Nicotinamide N -methyltransferase promotes M2 macrophage polarization by IL6 and MDSC conversion by GM-CSF in gallbladder carcinoma

BACKGROUND AND AIMS

Nicotinamide N -methyltransferase (NNMT), an enzyme responsible for the methylation of nicotinamide, is involved in many metabolic pathways in adipose tissue and the liver. However, the role of NNMT in editing the tumor immune microenvironment is not well understood.

APPROACH AND RESULTS

Here, we identified that NNMT can promote IL6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression by decreasing the tri-methyl-histone H3 levels on the promoters of IL6 and CSF2 (encoding GM-CSF) and CCAAT/Enhancer Binding Protein, an essential transcription factor for IL6 expression, thus promoting differentiation of macrophages into M2 type tumor-associated macrophages and generation of myeloid-derived suppressor cells from peripheral blood mononuclear cells. Treatment of xenografted tumor models overexpressing NNMT gallbladder carcinoma (GBC) cells with the NNMT inhibitor JBSNF-000088 resulted in compromised tumor development and decreased expression levels of IL6, GM-CSF, tumor-associated macrophage marker CD206, and myeloid-derived suppressor cell marker CD33 but increased expression levels of CD8. In addition, elevated expression of NNMT in tumors of patients with GBC was correlated with increased expression levels of CD206 and CD33 but with decreased levels of CD8 and survival of patients.

CONCLUSIONS

These data highlight the critical role of NNMT in GBC progression. Inhibition of NNMT by JBSNF-000088 is a potential molecular target for GBC immunotherapy.

Histone lactylation regulates cancer progression by reshaping the tumor microenvironment

As a major product of glycolysis and a vital signaling molecule, many studies have reported the key role of lactate in tumor progression and cell fate determination. Lactylation is a newly discovered post-translational modification induced by lactate. On the one hand, lactylation introduced a new era of lactate metabolism in the tumor microenvironment (TME), and on the other hand, it provided a key breakthrough point for elucidation of the interaction between tumor metabolic reprogramming and epigenetic modification. Studies have shown that the lactylation of tumor cells, tumor stem cells and tumor-infiltrating immune cells in TME can participate in the development of cancer through downstream transcriptional regulation, and is a potential and promising tumor treatment target. This review summarized the discovery and effects of lactylation, as well as recent research on histone lactylation regulating cancer progression through reshaping TME. We also focused on new strategies to enhance anti-tumor effects via targeting lactylation. Finally, we discussed the limitations of existing studies and proposed new perspectives for future research in order to further explore lactylation targets. It may provide a new way and direction to improve tumor prognosis.

Crosstalk between ferroptosis and macrophages: potential value for targeted treatment in diseases

Ferroptosis is a newly identified form of programmed cell death that is connected to iron-dependent lipid peroxidization. It involves a variety of physiological processes involving iron metabolism, lipid metabolism, oxidative stress, and biosynthesis of nicotinamide adenine dinucleotide phosphate, glutathione, and coenzyme Q10. So far, it has been discovered to contribute to the pathological process of many diseases, such as myocardial infarction, acute kidney injury, atherosclerosis, and so on. Macrophages are innate immune system cells that regulate metabolism, phagocytize pathogens and dead cells, mediate inflammatory reactions, promote tissue repair, etc. Emerging evidence shows strong associations between macrophages and ferroptosis, which can provide us with a deeper comprehension of the pathological process of diseases and new targets for the treatments. In this review, we summarized the crosstalk between macrophages and ferroptosis and anatomized the application of this association in disease treatments, both non-neoplastic and neoplastic diseases. In addition, we have also addressed problems that remain to be investigated, in the hope of inspiring novel therapeutic strategies for diseases.

The microRNA-4766/VEGFA axis mediates macrophage M2-type polarization to inhibit colorectal cancer proliferation and migration

OBJECTIVE

To investigate the miR-4766/VEGFA axis in regulating M2-type macrophage polarization under hypoxia and its effect on the proliferation and migration of colorectal cancer (CRC) cells.

METHODS

The differentially expressed genes (DEGs) in macrophages before and after hypoxia treatment in the dataset GSE154427 were analyzed. microRNA (miR)-4766 and VEGFA were selected as the research objects and then detected for mRNA expression and protein level using qRT-PCR and Western blot, respectively. The expression levels of M2 macrophage markers such as CD206, CD163, and ARG1 were detected to determine the M2-type macrophage polarization. The targeted binding of miR-4766 to VEGFA was verified using Dual-luciferase reporter gene assay. CCK-8 and Transwell assays were performed, respectively, to detect the capacity of cells to proliferate and migrate. IL-10 and TGF-β levels in the conditioned medium were detected using ELISA.

RESULTS

miR-4766 was upregulated, and VEGFA was downregulated in hypoxia-treated macrophages. miR-4766 inhibited, while VEGFA promoted the polarization of M2-type macrophages. miR-4766 targeted and negatively regulated VEGFA. miR-4766 inhibited the polarization of M2-type macrophages and then suppressed CRC cell proliferation and migration via targeting VEGFA.

CONCLUSION

Restoring miR-4766 expression to inhibit VEGFA expression promised to be a potential strategy to suppress CRC development.

The Interaction between Macrophages and Triple-negative Breast Cancer Cells Induces ROS-Mediated Interleukin 1α Expression to Enhance Tumorigenesis and Metastasis

Triple-negative breast cancer (TNBC) has higher mortality than non-TNBC because of its stronger metastatic capacity. Increasing studies reported that TNBC tumors had more macrophage infiltration than non-TNBC tumors, which promoted the metastasis of TNBC cells. However, how TNBC cells become more malignant after interacting with macrophages is less reported. In this study, it is observed that when TNBC cells are co-cultured with macrophages, they display higher viability and stronger metastatic ability than non-TNBC cells. Mechanistic studies reveal that TNBC cells acquired these abilities via interactions with macrophages in three phases. First, within 12 h of co-culture with macrophages, some TNBC cells have significantly elevated levels of reactive oxygen species (ROS), which upregulate interleukin 1α (IL1α) expression in ERK1/2-c-Jun- and NF-κB-dependent manners at 24-48 h. Second, the secreted IL1α bound to IL1R1 activates the ERK1/2-ZEB1-VIM pathway which increases metastasis. Third, IL1α/IL1R1 facilitates its own synthesis and induces the expression of IL1β and IL8 at 72-96 h through the MKK4-JNK-c-Jun and NF-κB signaling pathways. Moreover, a higher level of IL1α is positively correlated with more macrophage infiltration and shorter overall survival in breast cancer patients. Thus, reducing ROS elevation or downregulating IL1α expression can serve as new strategies to decrease metastasis of TNBC.

DLGAP5 promotes gallbladder cancer migration and tumor-associated macrophage M2 polarization by activating cAMP

BACKGROUND

Although disc large associated protein family (DLGAP5) has been reported to be involved in a variety of tumor pathologic processes, its expression and mechanism in gallbladder cancer (GBC) are still uncertain. Macrophages were divided into M1 and M2 macrophages. TAM is more closely defined as M2 polarized macrophages, which plays a key role in cancer progression.

OBJECTIVE

To clarify the role of disc large associated protein family (DLGAP5) in gallbladder cancer (GBC) progression and investigate the mechanism.

METHODS

Differential genes in 10 normal paracancer tissues and 10 GBC tissues in GSE139682 from NCBI-GEO were analyzed by R language. Bioinformation analysis and clinical sample analysis were performed to detect DLGAP5 expression in GBC and its correlation with prognosis. CCK-8, EDU, transwell, wound closure, and Immunoblot were performed to detect its effects on the function of GBC cells. GST-pulldown showed the direct interact between DLGAP5 and cAMP. Macrophage polarization assay was further conducted to detect the effects of DLGAP5 on macrophage M2 polarization. The tumor growth assays were further conducted to confirm its role in mice.

RESULTS

Biological analysis and clinical samples confirmed that DLGAP5 was increased in GBC and strongly related to poor prognosis in patients with GBC. After overexpression of DLGAP5 in GBC cell lines, such as GBC-SD and NOZ cells, cell proliferation and migration were enhanced, and macrophages were polarized to M2. However, after DLGAP5 is knocked down, there is opposite effect. Mechanistically, DLGAP5 promotes the growth and migration of GBC-SD and NOZ cells and the M2 polarization of THP-1-derived macrophages by activating cyclic adenosine monophosphate (cAMP) pathway. In vivo, GBC-SD with DLGAP5 knockdown was subcutaneously injected into nude mice. It was found that after DLGAP5 knockdown, both tumor volume and tumor were reduced, and indicators related to proliferation and M2 polarization decreased.

CONCLUSION

Our study shows that DLGAP5 is significantly elevated in GBC and is strongly related to poor prognosis in patients with GBC. DLGAP5 promotes GBC proliferation, migration, and M2 polarization of macrophages through cAMP pathway, which provides a theoretical basis for the treatment of GBC and may become a promising therapeutic target.

Long non-coding RNA and the tumor microenvironment: Prospects for clinical applications in breast cancer

Breast cancer has surpassed lung cancer as the number one cancer worldwide, and invasion and metastasis are still the main causes of death in breast cancer patients. The tumor microenvironment (TME) is an important site for the growth of tumor cells nourished by vascular networks, and various components of the TME interact strongly with cancer cells and are one of the important mechanisms of tumor progression and metastasis. In recent years, many studies have reported that long non-coding RNAs (LncRNAs) are involved in the formation of TME and influence the process of tumorigenesis and metastasis. This paper reviews the basic characteristics and functional roles of LncRNA in breast cancer TME and introduces the various mechanisms of LncRNA in breast cancer microenvironment that induce breast cancer development and metastasis in three directions: immune cells, non-immune cells, and extracellular matrix in TME, providing potential biomarkers or therapeutic targets for clinical practice.

Therapeutic potential of single-nucleotide polymorphism-mediated interleukin-6 receptor blockade in cancer treatment: A Mendelian randomization study

Background

Interleukin-6 (IL-6) is a crucial member of the cytokine network and plays a pivotal role in the pathogenesis of various diseases, including cancer. IL-6 receptor (IL-6R) blockade is widely employed as a therapeutic strategy; however, its efficacy in anticancer therapy remains ambiguous.

Methods

An inverse variance-weighted Mendelian randomization (MR) analysis was conducted to assess the causal effects exerted by IL-6R blockade in remediating cancer. Drug-targeted single-nucleotide polymorphisms (SNPs) were introduced within 300 kb of the IL-6R gene. An instrumental variable comprising 26 SNPs represented IL-6 signaling downregulation and C-reactive protein level reduction. Datasets pertaining to the 33 types of cancer investigated in this study were acquired from the FinnGen genome-wide association study.

Results

The selected instrumental variable lowered fibrinogen levels, confirming its ability to mimic IL-6R blockade. IL-6R blockade exhibited therapeutic effects on five different cancer types documented in the FinnGen database (N = 334,364, including 76,781 cancer patients): bladder (odds ratios (OR) = 0.563), laryngeal (OR = 0.293), eye (OR = 0.098), gallbladder (OR = 0.059), and myeloid leukemia (OR = 0.442); however, it simultaneously elevated the risk of developing basal cell carcinoma (OR = 1.312) and melanoma (OR = 1.311). Sensitivity analyses did not alter the primary results.

Conclusion

Therefore, this study aimed to evaluate the potential and efficacy of SNP-based IL-6R blockade in treating cancer.

Monocarboxylate Transporter-1 (MCT1)-Mediated Lactate Uptake Protects Pancreatic Adenocarcinoma Cells from Oxidative Stress during Glutamine Scarcity Thereby Promoting Resistance against Inhibitors of Glutamine Metabolism

Metabolic compartmentalization of stroma-rich tumors, like pancreatic ductal adenocarcinoma (PDAC), greatly contributes to malignancy. This involves cancer cells importing lactate from the microenvironment (reverse Warburg cells) through monocarboxylate transporter-1 (MCT1) along with substantial phenotype alterations. Here, we report that the reverse Warburg phenotype of PDAC cells compensated for the shortage of glutamine as an essential metabolite for redox homeostasis. Thus, oxidative stress caused by glutamine depletion led to an Nrf2-dependent induction of MCT1 expression in pancreatic T3M4 and A818-6 cells. Moreover, greater MCT1 expression was detected in glutamine-scarce regions within tumor tissues from PDAC patients. MCT1-driven lactate uptake supported the neutralization of reactive oxygen species excessively produced under glutamine shortage and the resulting drop in glutathione levels that were restored by the imported lactate. Consequently, PDAC cells showed greater survival and growth under glutamine depletion when utilizing lactate through MCT1. Likewise, the glutamine uptake inhibitor V9302 and glutaminase-1 inhibitor CB839 induced oxidative stress in PDAC cells, along with cell death and cell cycle arrest that were again compensated by MCT1 upregulation and forced lactate uptake. Our findings show a novel mechanism by which PDAC cells adapt their metabolism to glutamine scarcity and by which they develop resistance against anticancer treatments based on glutamine uptake/metabolism inhibition.

A comprehensive analysis of the role of QPRT in breast cancer

To explore the clinical role of QPRT in breast cancer. The gene expression, methylation levels and prognostic value of QPRT in breast cancer was analyzed using TCGA data. Validation was performed using the data from GEO dataset and TNMPLOT database. Meta analysis method was used to pool the survival data for QPRT. The predictive values of QPRT for different drugs were retrieved from the ROC plot. The expression differences of QPRT in acquired drug-resistant and sensitive cell lines were analyzed using GEO datasets. GO and KEGG enrichment analysis were conducted for those genes which were highly co-expressed with QPRT in tissue based on TCGA data and which changed after QPRT knockdown. Timer2.0 was utilized to explore the correlation between QPRT and immune cells infiltration, and the Human Protein Atlas was used to analyse QPRT's single-cell sequencing data across different human tissues. The expression of QPRT in different types of macrophages, and the expression of QPRT were analysed after coculturing HER2+ breast cancer cells with macrophages. Additionally, TargetScan, Comparative Toxicogenomics and the connectivity map were used to research miRNAs and drugs that could regulate QPRT expression. Cytoscape was used to map the interaction networks between QPRT and other proteins. QPRT was highly expressed in breast cancer tissue and highly expressed in HER2+ breast cancer patients (P < 0.01). High QPRT expression levels were associated with worse OS, DMFS, and RFS (P < 0.01). Two sites (cg02640602 and cg06453916) were found to be potential regulators of breast cancer (P < 0.01). QPRT might predict survival benefits in breast cancer patients who received taxane or anthracycline. QPRT was associated with tumour immunity, especially in macrophages. QPRT may influence the occurrence and progression of breast cancer through the PI3K-AKT signalling pathway, Wnt signalling pathway, and cell cycle-related molecules.

Exosomes derived from LPS-preconditioned bone marrow-derived MSC modulate macrophage plasticity to promote allograft survival via the NF-κB/NLRP3 signaling pathway

OBJECTIVES

This study investigated whether exosomes from LPS pretreated bone marrow mesenchymal stem cells (LPS pre-MSCs) could prolong skin graft survival.

METHODS

The exosomes were isolated from the supernatant of MSCs pretreated with LPS. LPS pre-Exo and rapamycin were injected via the tail vein into C57BL/6 mice allografted with BALB/c skin; graft survival was observed and evaluated. The accumulation and polarization of macrophages were examined by immunohistochemistry. The differentiation of macrophages in the spleen was analyzed by flow cytometry. For in vitro, an inflammatory model was established. Specifically, bone marrow-derived macrophages (BMDMs) were isolated and cultured with LPS (100 ng/ml) for 3 h, and were further treated with LPS pre-Exo for 24 h or 48 h. The molecular signaling pathway responsible for modulating inflammation was examined by Western blotting. The expressions of downstream inflammatory cytokines were determined by Elisa, and the polarization of macrophages was analyzed by flow cytometry.

RESULTS

LPS pre-Exo could better ablate inflammation compared to untreated MSC-derived exosomes (BM-Exo). These loaded factors inhibited the expressions of inflammatory factors via a negative feedback mechanism. In vivo, LPS pre-Exo significantly attenuated inflammatory infiltration, thus improving the survival of allogeneic skin graft. Flow cytometric analysis of BMDMs showed that LPS pre-Exo were involved in the regulation of macrophage polarization and immune homeostasis during inflammation. Further investigation revealed that the NF-κB/NLRP3/procaspase-1/IL-1β signaling pathway played a key role in LPS pre-Exo-mediated regulation of macrophage polarization. Inhibiting NF-κB in BMDMs could abolish the LPS-induced activation of inflammatory pathways and the polarization of M1 macrophages while increasing the proportion of M2 cells.

CONCLUSION

LPS pre-Exo are able to switch the polarization of macrophages and enhance the resolution of inflammation. This type of exosomes provides an improved immunotherapeutic potential in prolonging graft survival.

Tumor suppressor p53 mediates interleukin-6 expression to enable cancer cell evasion of genotoxic stress

The tumor suppressor p53 primarily functions as a mediator of DNA damage-induced cell death, thereby contributing to the efficacy of genotoxic anticancer therapeutics. Here, we show, on the contrary, that cancer cells can employ genotoxic stress-induced p53 to acquire treatment resistance through the production of the pleiotropic cytokine interleukin (IL)-6. Mechanistically, DNA damage, either repairable or irreparable, activates p53 and stimulates Caspase-2-mediated cleavage of its negative regulator mouse double minute 2 (MDM2) creating a positive feedback loop that leads to elevated p53 protein accumulation. p53 transcriptionally controls the major adenosine triphosphate (ATP) release channel pannexin 1 (Panx1), which directs IL-6 induction via a mechanism dependent on the extracellular ATP-activated purinergic P2 receptors as well as their downstream intracellular calcium (iCa2+)/PI3K/Akt/NF-ĸB signaling pathway. Thus, p53 silencing impairs Panx1 and IL-6 expression and renders cancer cells sensitive to genotoxic stress. Moreover, we confirm that IL-6 hampers the effectiveness of genotoxic anticancer agents by mitigating DNA damage, driving the expression of anti-apoptotic Bcl-2 family genes, and maintaining the migratory and invasive properties of cancer cells. Analysis of patient survival and relevant factors in lung cancer and pan-cancer cohorts supports the prognostic and clinical values of Panx1 and IL-6. Notably, IL-6 secreted by cancer cells during genotoxic treatments promotes the polarization of monocytic THP-1-derived macrophages into an alternative (M2-like) phenotype that exhibits impaired anti-survival activities but enhanced pro-metastatic effects on cancer cells as compared to nonpolarized macrophages. Our study reveals the precise mechanism for genotoxic-induced IL-6 and suggests that targeting p53-mediated IL-6 may improve the responsiveness of cancer cells to genotoxic anticancer therapy.

Interaction between Macrophages and Adipose Stromal Cells Increases the Angiogenic and Proliferative Potential of Pregnancy-Associated Breast Cancers

Pregnancy associated breast cancers (PABCs) exhibit increased aggressiveness and overall poorer survival. During lactation, changes take place in the breast tissue microenvironment that lead to increased macrophage recruitment and alterations in adipose stromal cells (ASC-Ls). The interaction of these cells in PABCs could play a role in the increased aggressiveness of these cancers. We utilized an in vitro co-culture model to recreate the interactions of ASC-Ls and macrophages in vivo. We performed qRT-PCR to observe changes in gene expression and cytokine arrays to identify transcriptional changes that result in an altered microenvironment. Additionally, functional assays were performed to further elicit how these changes affect tumorigenesis. The co-culture of ASC-Ls and macrophages altered both mRNA expression and cytokine secretion in a tumor promoting manner. Tumorigenic cytokines, such as IL-6, CXCL1, CXCL5, and MMP-9 secretion levels, were enhanced in the co-culture. Additionally, conditioned media from the co-culture elevated the tumor cell proliferation and angiogenic potential of endothelial cells. These finds indicate that the changes seen in the microenvironment of PABC, specifically the secretion of cytokines, play a role in the increased tumorigenesis of PABCs by altering the microenvironment to become more favorable to tumor progression.

MiR-662 is associated with metastatic relapse in early-stage breast cancer and promotes metastasis by stimulating cancer cell stemness

BACKGROUND

Breast cancer (BC) metastasis, which often occurs in bone, contributes substantially to mortality. MicroRNAs play a fundamental role in BC metastasis, although microRNA-regulated mechanisms driving metastasis progression remain poorly understood.

METHODS

MiRome analysis in serum from BC patients was performed by TaqMan™ low-density array. MiR-662 was overexpressed following MIMIC-transfection or lentivirus transduction. Animal models were used to investigate the role of miR-662 in BC (bone) metastasis. The effect of miR-662-overexpressing BC cell conditioned medium on osteoclastogenesis was investigated. ALDEFLUOR assays were performed to study BC stemness. RNA-sequencing transcriptomic analysis of miR-662-overexpressing BC cells was performed to evaluate gene expression changes.

RESULTS

High levels of hsa-miR-662 (miR-662) in serum from BC patients, at baseline (time of surgery), were associated with future recurrence in bone. At an early-stage of the metastatic disease, miR-662 could mask the presence of BC metastases in bone by inhibiting the differentiation of bone-resorbing osteoclasts. Nonetheless, metastatic miR-662-overexpressing BC cells then progressed as overt osteolytic metastases thanks to increased stem cell-like traits.

CONCLUSIONS

MiR-662 is involved in BC metastasis progression, suggesting it may be used as a prognostic marker to identify BC patients at high risk of metastasis.

Tumor cell-derived exosomes regulate macrophage polarization: Emerging directions in the study of tumor genesis and development

As an extracellular vesicle, exosomes play an important role in intercellular information transmission, delivering cargos of the parent cell, such as RNA, DNA, proteins, and lipids, activating different signaling pathways in the target cell and regulating inflammation, angiogenesis, and tumor progression. In particular, exosomes secreted by tumor cells can change the function of surrounding cells, creating a microenvironment conducive to tumor growth and metastasis. For example, after macrophages phagocytose exosomes and accept their cargos, they activate macrophage polarization-related signaling pathways and polarize macrophages into M1 or M2 types to exert antitumor or protumor functions. Currently, the study of exosomes affecting the polarization of macrophages has attracted increasing attention. Therefore, this paper reviews relevant studies in this field to better understand the mechanism of exosome-induced macrophage polarization and provide evidence for exploring novel targets for tumor therapy and new diagnostic markers in the future.

Possible Role of IL-6R/STAT3/MiRNA-34a Feedback Loop in Osteosarcoma

OBJECTIVE

Osteosarcoma is considered the most common primary malignant tumor that develops from the primary osteoblasts. MiRNAs are small non-coding RNAs that play a key role in tumorigenesis. The aim of this study was to detect the possible relationship between expression levels of miRNA-34a and levels of Signal transducer and activator of transcription 3 (STAT3) and interleukin-6 receptor (IL-6R) in osteosarcoma and the possible role of this relationship in development of metastases in these patients.

METHODS

A total of thirty-six (36) bone samples were included in the study. They were divided into 3 groups: Group (I): Twelve normal bone samples as control group. Group (II): Twelve patients with non-metastatic osteosarcoma. Group (III): Twelve patients with metastatic osteosarcoma. MiRNA-34a expression levels were estimated using qRT-PCR. STAT3 and IL-6R levels were measured by ELISA.

RESULTS

Expression level of miRNA-34a was downregulated in osteosarcoma groups compared to control group. STAT3 and IL-6R levels were upregulated in osteosarcoma groups compared to control group. This difference in expression levels was found to be more significant in the metastatic group than the non-metastatic one (P<0.001 each). There was a significant positive correlation between STAT3 and IL-6R (r=0.868, P<0.001), and a significant inverse correlation between IL6 and miRNA-34a (r=-0.993, P<0.001).

CONCLUSION

miRNA-34a, STAT3 and IL-6R feedback loop could be a potential target for treatment of osteosarcoma and can be used as prognostic indicator for this disease.

High glucose dialysate-induced peritoneal fibrosis: Pathophysiology, underlying mechanisms and potential therapeutic strategies

Peritoneal dialysis is an efficient renal replacement therapy for patients with end-stage kidney disease. However, continuous exposure of the peritoneal membrane to dialysate frequently leads to peritoneal fibrosis, which alters the function of the peritoneal membrane and results in withdrawal from peritoneal dialysis in patients. Among others, high glucose dialysate is considered as a predisposing factor for peritoneal fibrosis in patients on peritoneal dialysis. Glucose-induced inflammation, metabolism disturbance, activation of the renin-angiotensin-aldosterone system, angiogenesis and noninflammation-induced reactive oxygen species are implicated in the pathogenesis of high glucose dialysate-induced peritoneal fibrosis. Specifically, high glucose causes chronic inflammation and recurrent peritonitis, which could cause migration and polarization of inflammatory cells, as well as release of cytokines and fibrosis. High glucose also interferes with lipid metabolism and glycolysis by activating the sterol-regulatory element-binding protein-2/cleavage-activating protein pathway and increasing hypoxia inducible factor-1α expression, leading to angiogenesis and peritoneal fibrosis. Activation of the renin-angiotensin-aldosterone system and Ras-mitogen activated protein kinase signaling pathway is another contributing factor in high glucose dialysate-induced fibrosis. Ultimately, activation of the transforming growth factor-β1/Smad pathway is involved in mesothelial-mesenchymal transition or epithelial-mesenchymal transition, which leads to the development of fibrosis. Although possible intervention strategies for peritoneal dialysate-induced fibrosis by targeting the transforming growth factor-β1/Smad pathway have occasionally been proposed, lack of laboratory evidence renders clinical decision-making difficult. We therefore aim to revisit the upstream pathways of transforming growth factor-beta1/Smad and propose potential therapeutic targets for high glucose-induced peritoneal fibrosis.

Targeted miR-34a delivery with PD1 displayed bacterial outer membrane vesicles-coated zeolitic imidazolate framework nanoparticles for enhanced tumor therapy

MicroRNA (miRNA) has been widely used as an effective gene drug for tumor therapy, but its chemical instability limited its therapeutic application in vivo. In this research, we fabricate an efficient miRNA nano-delivery system using zeolitic imidazolate framework-8 (ZIF-8) coated with bacterial outer membrane vesicles (OMVs), aimed for cancer treatment. The acid-sensitive ZIF-8 core enables this system to encapsulate miRNA and release them from lysosome quickly and efficiently in the target cells. The OMVs engineered to display programmed death receptor 1 (PD1) on the surface provides a specific tumor-targeting capability. Using a murine breast cancer model, we show that this system has high miRNA delivery efficiency and accurate tumor targeting. Moreover, the miR-34a payloads in carriers can further synergize with immune activation and checkpoint inhibition triggered by OMV-PD1 to enhance tumor therapeutic efficacy. Overall, this biomimetic nano-delivery platform provides a powerful tool for the intracellular delivery of miRNA and has great potential in RNA-based cancer therapeutic applications.

Acetyl-cinobufagin suppresses triple-negative breast cancer progression by inhibiting the STAT3 pathway

BACKGROUND

The incidence of breast cancer (BC) worldwide has increased substantially in recent years. Epithelial-mesenchymal transition (EMT) refers to a crucial event impacting tumor heterogeneity. Although cinobufagin acts as an effective anticancer agent, the clinical use of cinobufagin is limited due to its strong toxicity. Acetyl-cinobufagin, a pre-drug of cinobufagin, was developed and prepared with greater efficacy and lower toxicity.

METHODS

A heterograft mouse model using triple negative breast cancer (TNBC) cell lines, was used to evaluate the potency of acetyl-cinobufagin. Signal transducer and stimulator of transcription 3 (STAT3)/EMT involvement was investigated by gene knockout experiments using siRNA and Western blot analysis.

RESULTS

Acetyl-cinobufagin inhibited proliferation, migration, and cell cycle S/G2 transition and promoted apoptosis in TNBC cells in vitro. In general, IL6 triggered the phosphorylation of the transcription factor STAT3 thereby activating the STAT3 pathway and inducing EMT. Mechanistically, acetyl-cinobufagin suppressed the phosphorylation of the transcription factor STAT3 and blocked the interleukin (IL6)-triggered translocation of STAT3 to the cell nucleus. In addition, acetyl-cinobufagin suppressed EMT in TNBC by inhibiting the STAT3 pathway. Experiments in an animal model of breast cancer clearly showed that acetyl-cinobufagin was able to reduce tumor growth.

CONCLUSIONS

The findings of this study support the potential clinical use of acetyl-cinobufagin as a STAT3 inhibitor in TNBC adjuvant therapy.

Functions and mechanisms of lactylation in carcinogenesis and immunosuppression

As critical executors regulating many cellular operations, proteins determine whether living activities can be performed in an orderly and efficient manner. Precursor proteins are inert and must be modified posttranslationally to enable a wide range of protein types and functions. Protein posttranslational modifications (PTMs) are well recognized as being directly associated with carcinogenesis and immune modulation and have emerged as important targets for cancer detection and treatment. Lactylation (Kla), a novel PTM associated with cellular metabolism found in a wide range of cells, interacts with both histone and nonhistone proteins. Unlike other epigenetic changes, Kla has been linked to poor tumor prognosis in all current studies. Histone Kla can affect gene expression in tumors and immunological cells, thereby promoting malignancy and immunosuppression. Nonhistone proteins can also regulate tumor progression and treatment resistance through Kla. In this review, we aimed to summarize the role of Kla in the onset and progression of cancers, metabolic reprogramming, immunosuppression, and intestinal flora regulation to identify new molecular targets for cancer therapy and provide a new direction for combined targeted therapy and immunotherapy.

Signal-transducing adaptor protein 1 (STAP1) in microglia promotes the malignant progression of glioma

BACKGROUND

Glioma is the most malignant primary brain tumor with a poor survival time. The tumour microenvironment, especially glioma-associated microglia/macrophages (GAMs), plays an important role in the pathogenesis of glioma. Currently, microglia (CD11b+/CD45Low) and macrophages (CD11b+/CD45High) are distinguished as distinct cell types due to their different origins. Moreover, signal-transducing adaptor protein 1 (STAP1) plays a role in tumourigenesis and immune responses. However, to date, no studies have been reported on STAP1 in GAMs.

METHODS

The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases were used to investigate the association between STAP1 mRNA levels and clinical parameters (grades, mutations in isocitrate dehydrogenase, and overall survival). RNA-sequencing, qRT-PCR, Western blotting, immunohistochemistry and immunofluorescence analyses were performed to detect the expression level of STAP1 and related proteins. BV-2 cells were used to construct a STAP1-overexpressing cell line. Phagocytosis of BV-2 cells was assessed by flow cytometry and fluorescence microscopy. C57BL/6 mice were used to establish orthotopic and subcutaneous glioma mouse models. Glioma growth was monitored by bioluminescence imaging.

RESULTS

STAP1 expression in glioma-associated microglia is positively correlated with the degree of malignancy and poor prognosis of glioma. Moreover, STAP1 may promote M2-like polarisation by increasing ARG1 expression and inhibiting microglial phagocytosis of microglia. Increased ARG1 may be associated with the IL-6/STAT3 pathway. Impaired phagocytosis may be associated with decreased cofilin and filopodia.

CONCLUSION

STAP1 is positively associated with the degree of glioma malignancy and may represent a potential novel therapeutic target for glioma.

Irradiated Mammary Spheroids Elucidate Mechanisms of Macrophage-Mediated Breast Cancer Recurrence

Introduction

While most patients with triple negative breast cancer receive radiation therapy to improve outcomes, a significant subset of patients continue to experience recurrence. Macrophage infiltration into radiation-damaged sites has been shown to promote breast cancer recurrence in pre-clinical models. However, the mechanisms that drive recurrence are unknown. Here, we developed a novel spheroid model to evaluate macrophage-mediated tumor cell recruitment.

Methods

We characterized infiltrating macrophage phenotypes into irradiated mouse mammary tissue via flow cytometry. We then engineered a spheroid model of radiation damage with primary fibroblasts, macrophages, and 4T1 mouse mammary carcinoma cells using in vivo macrophage infiltration results to inform our model. We analyzed 4T1 infiltration into spheroids when co-cultured with biologically relevant ratios of pro-healing M2:pro-inflammatory M1 macrophages. Finally, we quantified interleukin 6 (IL-6) secretion associated with conditions favorable to tumor cell infiltration, and we directly evaluated the impact of IL-6 on tumor cell invasiveness in vitro and in vivo.

Results

In our in vivo model, we observed a significant increase in M2 macrophages in mouse mammary glands 10 days post-irradiation. We determined that tumor cell motility toward irradiated spheroids was enhanced in the presence of a 2:1 ratio of M2:M1 macrophages. We also measured a significant increase in IL-6 secretion after irradiation both in vivo and in our model. This secretion increased tumor cell invasiveness, and tumor cell invasion and recruitment were mitigated by neutralizing IL-6.

Conclusions

Our work suggests that interactions between infiltrating macrophages and damaged stromal cells facilitate breast cancer recurrence through IL-6 signaling.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12195-023-00775-x.

Integrative multi-omics analyses unravel the immunological implication and prognostic significance of CXCL12 in breast cancer

Background

CXCL12 is a vital factor in physiological and pathological processes, by inducing migration of multiple cells. We aimed to comprehensively detect the role of CXCL12 in breast cancer, and explore novel CXCL12-related biomarkers through integrative multi-omics analyses to build a powerful prognostic model for breast cancer patients.

Methods

Immunohistochemistry analysis of the tissue microarray was performed to evaluate the correlation between CXCL12 expression levels and breast cancer patient outcomes. Combined single-nucleus and spatial transcriptomics data was used to uncover the expression distribution of CXCL12 in breast cancer microenvironment. CXCL12-related genes were identified by WGCNA analysis. Univariate Cox and LASSO regression analyses were then conducted to screen prognostic genes from above CXCL12-related genes, followed by the construction of the CXCL12-related prognostic signature, identification of risk groups, and external validation of the prognostic signature. Analyses of biological function, mutation landscape, immune checkpoint genes and immune cells, were performed to further reveal the differences between high/low-risk groups. Paired single-cell RNA-seq and bulk RNA-seq were analyzed to further disclose the association between the risk score and the complex tumor immune microenvironment. To screen potential therapeutic agents for breast cancer patients, analyses of gene-drug correlation and sensitivity to immunotherapy were conducted.

Results

High expression of CXCL12 was linked with a prolonged survival in breast cancer. A total of 402 genes were identified by WGCNA analysis and 11 genes, covering VAT1L, TMEM92, SDC1, RORB, PCSK9, NRN1, NACAD, JPH3, GJA1, BMP8B and ADAMTS2, were screened as the candidate prognostic genes. Next, the prognostic signature was built and validated using these genes to predict the outcomes of breast cancers. The high-risk group patients exhibited significantly inferior prognoses. The combination of the risk score and tumor mutational burden (TMB) had remarkably improved performance in predicting patient outcomes. Besides, high-risk group patients showed higher infiltration of M2-like macrophages. Finally, several potential anticancer drugs were identified. The high-risk group patients were more sensitive to immunotherapy but resistant to docetaxel.

Conclusions

CXCL12 has important immunological implication and prognostic significance in breast cancer. The CXCL12-related prognostic model could well predict the prognosis and treatment response of breast cancers.

Lnc NR2F1-AS1 Promotes Breast Cancer Metastasis by Targeting the MiR-25-3p/ZEB2 Axis

Background: Long noncoding RNAs (lncRNAs) substantially affect tumor metastasis and are aberrantly expressed in various cancers. However, its role in breast cancer (BC) remains unclear. Methods: A microarray assay of differentially expressed lncRNAs in epithelial-mesenchymal transition (EMT) and non-EMT cells was performed. The prognostic value of lnc NR2F1-AS1 expression in patients with BC was analyzed using The Cancer Genome Atlas database. Lnc NR2F1-AS1 expression levels in different BC cell lines were assessed using quantitative real-time PCR. The role of lnc NR2F1-AS1 in BC cell metastasis was investigated in vitro and in vivo. Dual luciferase reporter assay and RNA immunoprecipitation were performed to investigate the relationship between lnc NR2F1-AS1, miR-25-3p, and ZEB2. Results: High levels of lnc NR2F1-AS1 were observed in BC cells undergoing EMT and were closely correlated with adverse prognosis in patients with BC. Lnc NR2F1-AS1 knockdown significantly inhibited BC cell migration, invasiveness in vitro, and metastasis in vivo. Mechanistically, lnc NR2F1-AS1 competitively binds to miR-25-3p to impede ZEB2 degradation, a positive EMT transcription factor in BC. Conclusions: Our study revealed a novel lnc NR2F1-AS1/miR-25-3p/ZEB2 axis in BC metastasis and that lnc NR2F1-AS1 may serve as a potential therapeutic target for BC metastasis.

HSPB1 facilitates chemoresistance through inhibiting ferroptotic cancer cell death and regulating NF-κB signaling pathway in breast cancer

Chemoresistance is one of the major causes of therapeutic failure and poor prognosis for breast cancer patients, especially for triple-negative breast cancer patients. However, the underlying mechanism remains elusive. Here, we identified novel functional roles of heat shock protein beta-1 (HSPB1), regulating chemoresistance and ferroptotic cell death in breast cancer. Based on TCGA and GEO databases, HSPB1 expression was upregulated in breast cancer tissues and associated with poor prognosis of breast cancer patients, which was considered an independent prognostic factor for breast cancer. Functional assays revealed that HSPB1 could promote cancer growth and metastasis in vitro and in vivo. Furthermore, HSPB1 facilitated doxorubicin (DOX) resistance through protecting breast cancer cells from drug-induced ferroptosis. Mechanistically, HSPB1 could bind with Ikβ-α and promote its ubiquitination-mediated degradation, leading to increased nuclear translocation and activation of NF-κB signaling. In addition, HSPB1 overexpression led to enhanced secretion of IL6, which further facilitated breast cancer progression. These findings revealed that HSPB1 upregulation might be a key driver to progression and chemoresistance through regulating ferroptosis in breast cancer while targeting HSPB1 could be an effective strategy against breast cancer.

IL-6 upregulates the expression of IL-6R through the JAK2/STAT3 signalling pathway to promote progression of hepatocellular carcinoma

The progression of hepatocellular carcinoma (HCC) involves multifactor, multistep interactions. High expression of interleukin-6 receptor (IL-6R) plays an important role in the occurrence and development of tumours, but the regulatory mechanism of IL-6R expression and its function in HCC have not been fully defined. Western blot was used to evaluate the phosphorylation of key kinases in the JAK2/STAT3 pathway and the protein expression levels of related proliferation molecules, migration molecules and apoptotic molecules. The antiapoptosis, migration and proliferation of cells of each group were analysed with JC-1 to judge the cell apoptosis rate, the EdU method to determine the proliferation vitality of the cells, clone formation experiments and Transwell experiments. High expression of IL-6R in cell lines, lower protein levels of the apoptotic molecules c-Caspase7 and c-Caspase3 and higher protein levels of the proliferative molecules p-P70S6K and migration molecules MMP9 and MMP2 were consistent with stronger antiapoptosis, proliferation and migration. Interestingly, IL-6 upregulated the expression of IL-6R by activating the JAK2/STAT3 signalling pathway. Also, the expression of IL-6R protein was downregulated after lentivirus knockdown of STAT3. In nude mice bearing subcutaneous tumours, upregulation of IL-6R expression after activation of the JAK2/STAT3 signalling pathway by IL-6 significantly increased tumour growth. Moreover, the expression of IL-6R protein was downregulated, and the terminal tumour volume was significantly downregulated in the lentiviral STAT3 knockdown group. IL-6 regulated the transcription of IL-6R through the activation of the JAK2/STAT3 signalling pathway.

MicroRNAs as Targets for Cancer Diagnosis: Interests and Limitations

MicroRNAs are small RNAs with ability to attach to the large number of RNA that regulate gene expression on post-transcriptional level via inhibition or degradation of specific mRNAs. MiRNAs in cells are the primary regulators of functions such as cell growth, differentiation, and apoptosis and considerably influence cell function. The expression levels of microRNAs change in human diseases, including cancer. These changes highlight their essential role in cancer pathogenesis. Ubiquitous irregular expression profiles of miRNAs have been detected in various human cancers using genome-wide identification techniques, which are emerging as novel diagnostic and prognostic cancer biomarkers of high specificity and sensitivity. The measurable miRNAs with enhanced stability in blood, tissues, and other body fluids provide a comprehensive source of miRNA-dependent biomarkers for human cancers. The leading role of miRNAs as potential biomarkers in human cancers is discussed in this article. In addition, the interests and difficulties of miRNAs as biomarkers have been explored.

Deciphering Common Traits of Breast and Ovarian Cancer Stem Cells and Possible Therapeutic Approaches

Breast cancer (BC) and ovarian cancer (OC) are among the most common and deadly cancers affecting women worldwide. Both are complex diseases with marked heterogeneity. Despite the induction of screening programs that increase the frequency of earlier diagnosis of BC, at a stage when the cancer is more likely to respond to therapy, which does not exist for OC, more than 50% of both cancers are diagnosed at an advanced stage. Initial therapy can put the cancer into remission. However, recurrences occur frequently in both BC and OC, which are highly cancer-subtype dependent. Therapy resistance is mainly attributed to a rare subpopulation of cells, named cancer stem cells (CSC) or tumor-initiating cells, as they are capable of self-renewal, tumor initiation, and regrowth of tumor bulk. In this review, we will discuss the distinctive markers and signaling pathways that characterize CSC, their interactions with the tumor microenvironment, and the strategies they employ to evade immune surveillance. Our focus will be on identifying the common features of breast cancer stem cells (BCSC) and ovarian cancer stem cells (OCSC) and suggesting potential therapeutic approaches.

Lipid metabolism reprogramming of CD8+ T cell and therapeutic implications in cancer

Effector, memory and exhaustion are three phenotypes of CD8⁺ T cell. In tumor microenvironment (TME), metabolism dysfunction of the three should take the blame for immune escape. Against background of CD8⁺ T cell in normal development, multiple determinants in TME, including nutrition competition, PD-1 signals and other cancer- CD8⁺ T cell interaction, cause metabolism reprograming, including failure in energy metabolism and other abnormal lipid metabolism. Further, incompatibility of different CD8⁺ T cell metabolism pattern results in unresponsiveness of immune checkpoint blockade (ICB). Therefore, combination of ICB and drugs aiming at abnormal lipid metabolism provides promising direction to improve cancer therapy.

Targeting molecular cross-talk between tumor cells and tumor associated macrophage as therapeutic strategy in triple negative breast cancer

Triple-negative Breast cancer (TNBC) is a subtype of breast cancer (BC) that lacks expression for ER/PR/Her2 receptors and is associated with aggressive disease pathogenesis and the worst prognosis among other subtypes of BC. Accumulating evidence-based studies indicate the high immunogenic ability of TNBC tumors and the applicability of immunotherapeutic strategies to overcome therapy resistance and tumor recurrence in TNBC patients. However, not all TNBC patients respond equally well to current immunotherapies that mainly target the adaptive immune system for tumor rejection. Recent studies are contemplating the efficacy of tumor-associated macrophage (TAM) targeted therapies since these subpopulations of cells comprise one of the major components of tumor-infiltrating immune cells (TIIs) in the TNBC tumor microenvironment (TME) and play an essential role in priming the adaptive immune response mediators towards both antitumorigenic and pro-tumorigenic response facilitated by intercellular cross-talk between tumor cells and TAM populations present within TNBC-TME. The present review discusses these molecular mechanisms and their consequence on the progression of TNBC tumors. Also, the therapeutic strategies targeting candidate genes/pathways involved in molecular cross-talk between TAM-TNBC cells and their impact on the development and progression of TNBC tumors are also discussed.

The NR_109/FUBP1/c-Myc axis regulates TAM polarization and remodels the tumor microenvironment to promote cancer development

BACKGROUND

Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and exert an important role in tumor progression. Due to the heterogeneity and plasticity of TAMs, modulating the polarization states of TAMs is considered as a potential therapeutic strategy for tumors. Long noncoding RNAs (lncRNAs) have been implicated in various physiological and pathological processes, yet the underlying mechanism on how lncRNAs manipulate the polarization states of TAMs is still unclear and remains to be further investigated.

METHODS

Microarray analyses were employed to characterize the lncRNA profile involved in THP-1-induced M0, M1 and M2-like macrophage. Among those differentially expressed lncRNAs, NR_109 was further studied, for its function in M2-like macrophage polarization and the effects of the condition medium or macrophages mediated by NR_109 on tumor proliferation, metastasis and TME remodeling both in vitro and in vivo. Moreover, we revealed how NR_109 interacted with far upstream element-binding protein 1 (FUBP1) to regulate the protein stability through hindering ubiquitination modification by competitively binding with JVT-1. Finally, we examined sections of tumor patients to probe the correlation among the expression of NR_109 and related proteins, showing the clinical significance of NR_109.

RESULTS

We found that lncRNA NR_109 was highly expressed in M2-like macrophages. Knockdown NR_109 impeded IL-4 induced M2-like macrophage polarization and significantly reduced the activity of M2-like macrophages to support the proliferation and metastasis of tumor cells in vitro and in vivo. Mechanistically, NR_109 competed with JVT-1 to bind FUBP1 at its C-terminus domain, impeded the ubiquitin-mediated degradation of FUBP1, activated c-Myc transcription and thus promoted M2-like macrophages polarization. Meanwhile, as a transcription factor, c-Myc could bind to the promoter of NR_109 and enhance the transcription of NR_109. Clinically, high NR_109 expression was found in CD163⁺ TAMs from tumor tissues and was positively correlated with poor clinical stages of patients with gastric cancer and breast cancer.

CONCLUSIONS

Our work revealed for the first time that NR_109 exerted a crucial role in regulating the phenotype-remodeling and function of M2-like macrophages via a NR_109/FUBP1/c-Myc positive feedback loop. Thus, NR_109 has great translational potentials in the diagnosis, prognosis and immunotherapy of cancer.

CAA-derived IL-6 induced M2 macrophage polarization by activating STAT3

BACKGROUND

Tumor-associated macrophages (TAMs) are the most abundant types of immune cells in the tumor microenvironment (TME) of breast cancer (BC). TAMs usually exhibit an M2 phenotype and promote tumor progression by facilitating immunosuppression. This study aimed to investigate the effect of CAA-derived IL-6 on macrophage polarization in promoting BC progression.

METHODS

Human BC samples and adipocytes co-cultured with 4T1 BC cells were employed to explore the properties of CAAs. The co-implantation of adipocytes and 4T1 cells in mouse tumor-bearing model and tail vein pulmonary metastasis model were constructed to investigate the impact of CAAs on BC malignant progression in vivo. The functional assays, qRT-PCR, western blotting assay and ELISA assay were employed to explore the effect of CAA-derived IL-6 on macrophage polarization and programmed cell death protein ligand 1 (PD-L1) expression.

RESULTS

CAAs were located at the invasive front of BC and possessed a de-differentiated fibroblast phenotype. CAAs facilitated the malignant behaviors of 4T1 cells in vitro, and promoted 4T1 tumor growth and pulmonary metastasis in vivo. The IHC staining of both human BC specimens and xenograft and the in vitro experiment indicated that CAAs could enhance infiltration of M2 macrophages in the TME of 4T1 BC. Furthermore, CAA-educated macrophages could enhance malignant behaviors of 4T1 cells in vitro. More importantly, CAAs could secret abundant IL-6 and thus induce M2 macrophage polarization by activating STAT3. In addition, CAAs could upregulate PD-L1 expression in macrophages.

CONCLUSIONS

Our study revealed that CAAs and CAA-educated macrophages enhanced the malignant behaviors of BC. Specifically, CAA-derived IL-6 induced migration and M2 polarization of macrophages via activation STAT3 and promoted macrophage PD-L1 expression, thereby leading to BC progression.

β-Glucan produced by Lentinus edodes suppresses breast cancer progression via the inhibition of macrophage M2 polarization by integrating autophagy and inflammatory signals

BACKGROUND

β-Glucan from Lentinus edodes (LNT), an edible mushroom, possesses strong anticancer activity. However, the therapeutic effects of LNT during the occurrence and progression of breast cancer and their underlying molecular mechanisms have not been elucidated.

METHODS

Mouse mammary tumor virus-polyoma middle tumor-antigen (MMTV-PyMT) transgenic mice were used as a breast cancer mouse model. Hematoxylin and eosin, immunohistochemical, and immunofluorescence staining were performed for histopathological analysis. Moreover, we developed an inflammatory cell model using tumor necrosis factor-α (TNF-α). Macrophage polarization was assessed using western blot analysis and immunofluorescence.

RESULTS

Orphan nuclear receptor 77 (Nur77) and sequestosome-1 (p62) were highly expressed and positively correlated with each other in breast cancer tissues. LNT significantly inhibited tumor growth, ameliorated inflammatory cell infiltration, and induced tumor cell apoptosis in PyMT transgenic mice. Moreover, LNT attenuated the ability of tumors to metastasize to lung tissue. Mechanistically, LNT treatment restrained macrophage polarization from M1 to M2 phenotype and promoted autophagic cell death by inhibiting Nur77 expression, AKT/mTOR signaling, and inflammatory signals in breast tumor cells. However, LNT did not exhibit a direct pro-autophagic effect on tumor cell death, except for its inhibitory effect on Nur77 expression. LNT-mediated autophagic tumor cell death depends on M1 macrophage polarization. In in vitro experiments, LNT inhibited the upregulation of p62, autophagy activation, and inflammatory signaling pathways in Nur77 cells.

CONCLUSION

LNT inhibited macrophage M2 polarization and subsequently blocked the AKT/mTOR and inflammatory signaling axes in breast cancer cells, thereby promoting autophagic tumor cell death. Thus, LNT may be a promising therapeutic strategy for breast cancer.

Tumor-Associated Macrophage Subsets: Shaping Polarization and Targeting

The tumor microenvironment (TME) is a critical regulator of tumor growth, progression, and metastasis. Among the innate immune cells recruited to the tumor site, macrophages are the most abundant cell population and are present at all stages of tumor progression. They undergo M1/M2 polarization in response to signals derived from TME. M1 macrophages suppress tumor growth, while their M2 counterparts exert pro-tumoral effects by promoting tumor growth, angiogenesis, metastasis, and resistance to current therapies. Several subsets of the M2 phenotype have been observed, often denoted as M2a, M2b, M2c, and M2d. These are induced by different stimuli and differ in phenotypes as well as functions. In this review, we discuss the key features of each M2 subset, their implications in cancers, and highlight the strategies that are being developed to harness TAMs for cancer treatment.

Extracellular Vesicles in Breast Cancer: From Biology and Function to Clinical Diagnosis and Therapeutic Management

Breast cancer (BC) is the first worldwide most frequent cancer in both sexes and the most commonly diagnosed in females. Although BC mortality has been thoroughly declining over the past decades, there are still considerable differences between women diagnosed with early BC and when metastatic BC is diagnosed. BC treatment choice is widely dependent on precise histological and molecular characterization. However, recurrence or distant metastasis still occurs even with the most recent efficient therapies. Thus, a better understanding of the different factors underlying tumor escape is mainly mandatory. Among the leading candidates is the continuous interplay between tumor cells and their microenvironment, where extracellular vesicles play a significant role. Among extracellular vesicles, smaller ones, also called exosomes, can carry biomolecules, such as lipids, proteins, and nucleic acids, and generate signal transmission through an intercellular transfer of their content. This mechanism allows tumor cells to recruit and modify the adjacent and systemic microenvironment to support further invasion and dissemination. By reciprocity, stromal cells can also use exosomes to profoundly modify tumor cell behavior. This review intends to cover the most recent literature on the role of extracellular vesicle production in normal and cancerous breast tissues. Specific attention is paid to the use of extracellular vesicles for early BC diagnosis, follow-up, and prognosis because exosomes are actually under the spotlight of researchers as a high-potential source of liquid biopsies. Extracellular vesicles in BC treatment as new targets for therapy or efficient nanovectors to drive drug delivery are also summarized.

Hepatocellular carcinoma-derived FOXO1 inhibits tumor progression by suppressing IL-6 secretion from macrophages

Tumor heterogeneity dominates tumor biological behavior and shapes the tumor microenvironment. However, the mechanisms of tumor genetic features modulate immunity response were not clearly clarified. Tumor associated macrophages (TAMs) exert distinct immune functions in the progression of hepatocellular carcinoma (HCC) based on the inducible phenotype. FOXO family members sense changes in the extracellular or intracellular environment by activating a series of signaling pathways. FOXO1, a transcription factor that a common suppressor in hepatocellular carcinoma, correlated with a better tumor biological behavior in HCC through shaping macrophages anti-tumour response. Here, we found that human HCC tissue microarray (TMA) slides were employed to showed tumor derived FOXO1 negatively related with distribution of protumour macrophages. This phenomenon was confirmed in mouse xenograft model and in vitro. HCC-derived FOXO1 inhibits tumorigenesis not only by targeting tumor cells but also by synchronizing with re-educated macrophages. These effects may be partially dependent on FOXO1 transcriptionally modulates IRF-1/nitrio oxide (NO) axis in exerting effects in macrophages and decreasing IL-6 releasing from macrophages in tumor microenvironment indirectly. This feedback suppressed the progression of HCC by inactivation of IL-6/STAT3 in HCC. It implicates the potential role of FOXO1 in the therapeutic effects for modulating immune response by targeting macrophages.

A20 affects macrophage polarization through the NLRP3 inflammasome signaling pathway and promotes breast cancer progression

Breast cancer is the most common malignant tumor in females, and the majority of patients succumb to metastasis. The present study aimed to investigate the association between tumor necrosis factor alpha-induced protein 3 (A20), NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) and tumor-associated macrophage polarization, and their effects on the proliferation and metastasis of breast cancer cells. The expression of A20 in breast cancer cells was analyzed by reverse transcription-quantitative PCR (RT-qPCR) and western blotting. RT-qPCR and western blotting were also used to confirm the transfection efficiency. The viability, clone formation, migration, invasion and angiogenesis of transfected breast cancer cells were detected by Cell Counting Kit-8, colony formation, wound healing, Transwell and tube formation assays, respectively. Activated macrophages, namely M1 and M2 type macrophages, were observed by double staining immunofluorescence. The levels of M1 and M2 macrophage markers were analyzed by qPCR. The expression of angiogenesis-related proteins and NLRP3 inflammasome activation-associated proteins was detected by western blotting. The results revealed that A20 was highly expressed in breast cancer cells. Interference with A20 inhibited the proliferation, invasion, migration and angiogenesis of breast cancer cells, and inhibited the M2-like polarization of macrophages. Interference with A20 promoted the activation of the NLRP3 inflammasome. The NLRP3 inhibitor MCC950 alleviated the effect of interference with A20 to promote macrophage proliferation and recruitment, as well as M2-like polarization. In conclusion, interference with A20 inhibited macrophage proliferation and M2-like polarization through the NLRP3 inflammasome signaling pathway to inhibit breast cancer progression.

Jiawei Yanghe Decoction suppresses breast cancer by regulating immune responses via JAK2/STAT3 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Jiawei Yanghe Decoction (JWYHD) is a widely used traditional Chinese medicine prescription in the clinical setting for the treatment of autoimmune diseases. Many studies showed that JWYHD has anti-tumor activities in cell and animal models. However, the anti-breast cancer effects of JWYHD and the underlying mechanisms of action remain unknown.

AIM OF STUDY

This study aimed to determine the anti-breast cancer effect and reveal the underlying mechanisms of action in vivo, in vitro and in silico.

MATERIALS AND METHODS

Orthotopic xenograft breast cancer mouse model and inflammatory zebrafish model were used to observe the anti-tumor effect and immune cell regulation of JWYHD. Moreover, the anti-inflammatory effect of JWYHD were evaluated by the expression of RAW 264.7 cells. JWYHD active ingredients were obtained by UPLC-MS/MS and potential targets were screened by network pharmacology. The therapeutic targets and signaling pathways predicted by computer were assessed by Western blot, real-time PCR (RT-PCR), immunohistochemistry (IHC) staining, and Enzyme-linked immunosorbent assays (ELISA) to explore the therapeutic mechanism of JWYHD against breast cancer. At last, Colivelin and Stattic were used to explore the effect of JWYHD on JAK2/STAT3 pathway.

RESULTS

JWYHD significantly decreased the tumor growth in a dose-dependent manner in the orthotopic xenograft breast cancer mouse model. Flow cytometry and IHC results indicated that JWYHD decreased the expressions of M2 macrophages and Treg while increasing M1 macrophages. Meanwhile, ELISA and Western blot results showed a decrease in IL-1β, IL-6, TNFα, PTGS2 and VEGFα in tumor tissue of JWYHD groups. The results were also verified in LPS-induced RAW264.7 cells and zebrafish inflammatory models. TUNEL assay and IHC results showed that JWYHD significantly induced apoptosis. Seventy-two major compounds in JWYHD were identified by UPLC-MS/MS and Network pharmacology. It was found that the significant binding affinity of JWYHD to TNFα, PTGS2, EGFR, STAT3, VEGFα and their expressions were inhibited by JWYHD. IHC and Western blot analysis showed that JWYHD could decrease the expression of JAK2/STAT3 pathway. Furthermore, Colivelin could reverse the decrease effect of JWYHD in vitro.

CONCLUSION

JWYHD exerts a significant anti-tumor effect mainly by inhibiting inflammation, activating immune responses and inducing apoptosis via the JAK2/STAT3 signaling pathway. Our findings provide strong pharmacological evidence for the clinical application of JWYHD in the management of breast cancer.

Establishing a Proteomics-Based Signature of AKR1C3-Related Genes for Predicting the Prognosis of Prostate Cancer

Aldo-keto reductase family 1 member C3 (AKR1C3) plays an important role in prostate cancer (PCa) progression, particularly in castration-resistant prostate cancer (CRPC). It is necessary to establish a genetic signature associated with AKR1C3 that can be used to predict the prognosis of PCa patients and provide important information for clinical treatment decisions. AKR1C3-related genes were identified via label-free quantitative proteomics of the AKR1C3-overexpressing LNCaP cell line. A risk model was constructed through the analysis of clinical data, PPI, and Cox-selected risk genes. Cox regression analysis, Kaplan-Meier (K-M) curves, and receiver operating characteristic (ROC) curves were used to verify the accuracy of the model, and two external datasets were used to verify the reliability of the results. Subsequently, the tumor microenvironment and drug sensitivity were explored. Moreover, the roles of AKR1C3 in the progression of PCa were verified in LNCaP cells. MTT, colony formation, and EdU assays were conducted to explore cell proliferation and drug sensitivity to enzalutamide. Migration and invasion abilities were measured using wound-healing and transwell assays, and qPCR was used to assess the expression levels of AR target genes and EMT genes. CDC20, SRSF3, UQCRH, INCENP, TIMM10, TIMM13, POLR2L, and NDUFAB1 were identified as AKR1C3-associated risk genes. These risk genes, established using the prognostic model, can effectively predict the recurrence status, immune microenvironment, and drug sensitivity of PCa. Tumor-infiltrating lymphocytes and several immune checkpoints that promote cancer progression were higher in high-risk groups. Furthermore, there was a close correlation between the sensitivity of PCa patients to bicalutamide and docetaxel and the expression levels of the eight risk genes. Moreover, through in vitro experiments, Western blotting confirmed that AKR1C3 enhanced SRSF3, CDC20, and INCENP expression. We found that PCa cells with a high expression of AKR1C3 have high proliferation ability and high migration ability and were insensitive to enzalutamide. AKR1C3-associated genes had a significant role in the process of PCa, immune responses, and drug sensitivity and offer the potential for a novel model for prognostic prediction in PCa.

Harnessing epithelial-mesenchymal plasticity to boost cancer immunotherapy

Immune checkpoint blockade (ICB) therapy is a powerful option for cancer treatment. Despite demonstrable progress, most patients fail to respond or achieve durable responses due to primary or acquired ICB resistance. Recently, tumor epithelial-to-mesenchymal plasticity (EMP) was identified as a critical determinant in regulating immune escape and immunotherapy resistance in cancer. In this review, we summarize the emerging role of tumor EMP in ICB resistance and the tumor-intrinsic or extrinsic mechanisms by which tumors exploit EMP to achieve immunosuppression and immune escape. We discuss strategies to modulate tumor EMP to alleviate immune resistance and to enhance the efficiency of ICB therapy. Our discussion provides new prospects to enhance the ICB response for therapeutic gain in cancer patients.

Functional heterogeneity of MCT1 and MCT4 in metabolic reprogramming affects osteosarcoma growth and metastasis

BACKGROUND

Osteosarcoma is the most common primary malignant bone tumor in adolescents and children and prone to develop lung metastasis. Its prognosis has been virtually unimproved over the last few decades, especially in patients with metastases, who suffer from a dismal survival. Recently, increasing attention has been devoted to monocarboxylate transporters-related (MCTs) metabolic reprogramming. However, the role of MCT1 and MCT4 in osteosarcoma progression and the underlying mechanisms remain to be further elucidated.

METHODS

In this study, we established MCT1 and/or MCT4 knockout cell lines by CRISPR/Cas9 genome editing technology. Then, we assessed glycolysis and oxidative phosphorylation capacities by measuring lactate flux and oxygen consumption. We also performed flowcytometry to test circulating tumor cells and PET/CT to evaluate glucose uptake.

RESULTS

MCT1 was found to be involved in both glycolysis and oxidative respiration due to its ability to transport lactate in both directions. MCT1 inhibition significantly reduced circulating tumor cells and distant metastases partially by increasing oxidative stress. MCT4 was primarily related to glycolysis and responsible for lactate export when the concentration of extracellular lactate was high. MCT4 inhibition dramatically suppressed cell proliferation in vitro and impaired tumor growth with reduction of glucose uptake in vivo.

CONCLUSIONS

Our results demonstrate the functional heterogeneity and redundancy of MCT1 and MCT4 in glucose metabolism and tumor progression in osteosarcoma. Thus, combined inhibition of MCT1 and MCT4 may be a promising therapeutic strategy for treating tumors expressing both transporters.

Exosomal miR-181a-5p derived from SAOS-2 cells promotes macrophages M2 polarization by targeting RORA

Although the interaction between tumor cells and tumor-associated macrophages (TAMs) has been widely studied; however, the mechanism of osteosarcoma cells in regulating the polarization of TAMs remains unclear. Exosomes from SAOS-2 cells were isolated and validated by electron microscopy and Western blot. Transfection of indicated plasmids was applied to modify the expressions of miR-181a-5p and RAR-related orphan receptor alpha (RORA). Flow cytometric analysis was carried out to analyze M1/M2 macrophage polarization. Quantitative real-time PCR was performed to determine the levels of miR-181a-5p and RORA. Protein levels of CD63, CD81, RORA, CD163, CD206, IL-10, CXCL10, and IL-1β were evaluated by Western blot. The direct interaction of miR-181a-5p and RORA was validated by dual-luciferase activity assay. The expression of miR-181a-5p was upregulated in osteosarcoma tissues and presented in SAOS-2-derived exosomes. SAOS-2-derived exosomes promoted the polarization of M2 macrophages by transferring miR-181a-5p. In addition, RORA was downregulated in osteosarcoma tissues and showed a negative correlation with miR-181a-5p. RORA was found to be the downstream target of miR-181a-5p in SAOS-2 cells. Inhibition of RORA reversed the effects of miR-181a-5p knockdown on the polarization of M2 macrophages. The results showed that exosomal miR-181a-5p derived from osteosarcoma cells induced polarization of M2 macrophages via targeting RORA.

Prognostic significance of absolute monocyte count and lymphocyte to monocyte ratio in mucosa-associated lymphoid tissue (MALT) lymphoma

To investigate the prognostic significance of peripheral blood absolute monocyte count (AMC) and lymphocyte to monocyte ratio (LMR) in mucosa-associated lymphoid tissue (MALT) lymphoma, we retrospectively analyzed 316 newly diagnosed patients with MALT lymphoma. The best cut-off value of AMC was 0.6 × 10⁹/L and LMR was 1.8 by x-tile according to progression-free survival (PFS). Multivariate analysis showed that MALT-IPI (p < 0.001), Eastern Cooperative Oncology Group performance status (ECOG PS) (p = 0.010), and LMR (p = 0.003) have independent prognostic significance for PFS, MALT-International Prognostic Index (MALT-IPI) (p = 0.018), β2-microglobulin (β2-MG) (p = 0.015), and LMR (p = 0.029) predicted poor overall survival (OS). Receiver-operator characteristic (ROC) curves were used to compare the prognostic prediction capability of MALT-IPI and MALT-IPI-M (MALT-IPI combined with LMR); area under the curves (AUCs) for MALT-IPI-M were larger than that for MALT-IPI both PFS (0.682 vs 0.654) and OS (0.804 vs 0.788). Our results indicated that that low level LMR at diagnosis was associated with inferior prognosis. The new prognostic index, MALT-IPI-M, enabled the risk stratification capability for MALT lymphoma survival.

Innate Immune Program in Formation of Tumor-Initiating Cells from Cells-of-Origin of Breast, Prostate, and Ovarian Cancers

Tumor-initiating cells (TICs), also known as cancer stem cells (CSCs), are cancer cells that can initiate a tumor, possess self-renewal capacity, and can contribute to tumor heterogeneity. TICs/CSCs are developed from their cells-of-origin. In breast, prostate, and ovarian cancers, progenitor cells for mammary alveolar cells, prostate luminal (secretory) cells, and fallopian tube secretory cells are the preferred cellular origins for their corresponding cancer types. These luminal progenitors (LPs) express common innate immune program (e.g., Toll-like receptor (TLR) signaling)-related genes. Microbes such as bacteria are now found in breast, prostate, and fallopian tube tissues and their corresponding cancer types, raising the possibility that their LPs may sense the presence of microbes and trigger their innate immune/TLR pathways, leading to an inflammatory microenvironment. Crosstalk between immune cells (e.g., macrophages) and affected epithelial cells (e.g., LPs) may eventually contribute to formation of TICs/CSCs from their corresponding LPs, in part via STAT3 and/or NFκB pathways. As such, TICs/CSCs can inherit expression of innate-immunity/TLR-pathway-related genes from their cells-of-origin; the innate immune program may also represent their unique vulnerability, which can be explored therapeutically (e.g., by enhancing immunotherapy via augmenting TLR signaling).

Cancer-Associated Adipocytes and Breast Cancer: Intertwining in the Tumor Microenvironment and Challenges for Cancer Therapy

Adipocytes are the main components in breast tissue, and cancer-associated adipocytes (CAAs) are one of the most important components in the tumor microenvironment of breast cancer (BC). Bidirectional regulation was found between CAAs and BC cells. BC facilitates the dedifferentiation of adjacent adipocytes to form CAAs with morphological and biological changes. CAAs increase the secretion of multiple cytokines and adipokines to promote the tumorigenesis, progression, and metastasis of BC by remodeling the extracellular matrix, changing aromatase expression, and metabolic reprogramming, and shaping the tumor immune microenvironment. CAAs are also associated with the therapeutic response of BC and provide potential targets in BC therapy. The present review provides a comprehensive description of the crosstalk between CAAs and BC and discusses the potential strategies to target CAAs to overcome BC treatment resistance.

Novel Anti-Cancer Products Targeting AMPK: Natural Herbal Medicine against Breast Cancer

Breast cancer is a common cancer in women worldwide. The existing clinical treatment strategies have been able to limit the progression of breast cancer and cancer metastasis, but abnormal metabolism, immunosuppression, and multidrug resistance involving multiple regulators remain the major challenges for the treatment of breast cancer. Adenosine 5'-monophosphate (AMP)-Activated Protein Kinase (AMPK) can regulate metabolic reprogramming and reverse the "Warburg effect" via multiple metabolic signaling pathways in breast cancer. Previous studies suggest that the activation of AMPK suppresses the growth and metastasis of breast cancer cells, as well as stimulating the responses of immune cells. However, some other reports claim that the development and poor prognosis of breast cancer are related to the overexpression and aberrant activation of AMPK. Thus, the role of AMPK in the progression of breast cancer is still controversial. In this review, we summarize the current understanding of AMPK, particularly the comprehensive bidirectional functions of AMPK in cancer progression; discuss the pharmacological activators of AMPK and some specific molecules, including the natural products (including berberine, curcumin, (-)-epigallocatechin-3-gallate, ginsenosides, and paclitaxel) that influence the efficacy of these activators in cancer therapy; and elaborate the role of AMPK as a potential therapeutic target for the treatment of breast cancer.

Crosstalk between cancer stem cells and the tumor microenvironment drives progression of premalignant oral epithelium

Cancer stem cells (CSC) are a subpopulation of cancer cells that exhibit properties of self-renewal and differentiation and have been implicated in metastasis and treatment failures. There is mounting evidence that carcinogen-initiated mucosal epithelial stem cells acquire the CSC phenotype following exposure to environmental or infectious mutagens and are responsible for promoting the malignant transformation of premalignant (dysplastic) epithelium. CSC further contribute to the progression of dysplasia by activating signaling pathways through crosstalk with various cell populations in the tumor microenvironment. Two cell types, tumor-associated macrophages (TAM) and vascular endothelial cells (EC) nurture CSC development, support CSC stemness, and contribute to tumor progression. Despite mounting evidence implicating CSC in the initiation and progression of dysplastic oral epithelium to squamous cell carcinoma (SCC), the molecular mechanisms underlying these synergistic biological processes remain unclear. This review will examine the mechanisms that underlie the transformation of normal epithelial stem cells into CSC and the mechanistic link between CSC, TAM, and EC in the growth and the malignant conversation of dysplastic oral epithelium.

ENO1 Promotes OSCC Migration and Invasion by Orchestrating IL-6 Secretion from Macrophages via a Positive Feedback Loop

Oral squamous cell carcinoma (OSCC) has a five-year survival rate of less than 50% due to its susceptibility to invasion and metastasis. Crosstalk between tumor cells and macrophages has been proven to play a critical role in tumor cell migration and invasion. However, the specific mechanisms by which tumor cells interact with macrophages have not been fully elucidated. This study sought to investigate the regulatory mechanism of tumor cell-derived alpha-enolase (ENO1) in the interaction between tumor cells and macrophages during OSCC progression. Small interfering RNA (siRNA) transfection and recombinant human ENO1 (rhENO1) stimulation were used to interfere with the interaction between tumor cells and macrophages. Our results showed that ENO1 was expressed higher in CAL27 cells than in HaCaT cells and regulated lactic acid release in CAL27 cells. Conditioned medium of macrophages (Macro-CM) significantly up-regulated the ENO1 mRNA expression and protein secretion in CAL27 cells. ENO1 promoted the migration and invasion of tumor cells by facilitating the epithelial-mesenchymal transition (EMT) through macrophages. ENO1 orchestrated the IL-6 secretion of macrophages via tumor cell-derived lactic acid and the paracrine ENO1/Toll-like receptor (TLR4) signaling pathway. In turn, IL-6 promoted the migration and invasion of tumor cells. Collectively, ENO1 promotes tumor cell migration and invasion by orchestrating IL-6 secretion of macrophages via a dual mechanism, thus forming a positive feedback loop to promote OSCC progression. ENO1 might be a promising therapeutic target which is expected to control OSCC progression.

LINC01798/miR-17-5p axis regulates ITGA8 and causes changes in tumor microenvironment and stemness in lung adenocarcinoma

Integrins are closely related to the occurrence and development of tumors. ITGA8 encodes the alpha 8 subunit of the heterodimeric integrin alpha8beta1. Studies on the role of this gene in the occurrence and development of lung cancer are scarce. The examination of public databases revealed that ITGA8 expression was significantly lower in tumor tissue than that in normal tissue, especially in lung cancer, renal carcinoma, and prostate cancer. Survival analysis of patients with lung adenocarcinoma revealed that higher ITGA8 expression had better prognosis. ITGA8 was positively related to immune checkpoints and immunomodulators, whereas B cell, CD4+ T cell, CD8+ T cell, neutrophil, macrophage, and dendritic cell infiltration had the same correlation. Moreover, ITGA8 was negatively related to cancer stemness. We used an online database to predict the miRNAs and lncRNAs that regulate ITGA8 and obtained the regulatory network of ITGA8 through correlation analysis and Kaplan-Meier survival analysis. Quantitative real-time PCR and western blot analyses showed that LINC01798 regulates ITGA8 expression through miR-17-5p. Therefore, the regulatory network of ITGA8 may serve as a new therapeutic target to improve the prognosis of patients with lung cancer.