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BACKGROUND AND AIMS: Liver fibrosis represents a global health burden, given the paucity of approved antifibrotic therapies. Liver sinusoidal endothelial cells (LSECs) play a major gatekeeping role in hepatic homeostasis and liver disease pathophysiology. In early tumorigenesis, runt-related transcription factor 3 (RUNX3) functions as a sentinel; however, its function in liver fibrosis in LSECs remains unclear. This study aimed to investigate the role of RUNX3 as an important regulator of the gatekeeping functions of LSECs and explore novel angiocrine regulators of liver fibrosis. APPROACH AND RESULTS: Mice with endothelial Runx3 deficiency develop gradual and spontaneous liver fibrosis secondary to LSEC dysfunction, thereby more prone to liver injury. Mechanistic studies in human immortalized LSECs and mouse primary LSECs revealed that IL-6/JAK/STAT3 pathway activation was associated with LSEC dysfunction in the absence of RUNX3. Single-cell RNA sequencing and quantitative RT-PCR revealed that leucine-rich alpha-2-glycoprotein 1 ( LRG1 ) was highly expressed in RUNX3-deficient and dysfunctional LSECs. In in vitro and coculture experiments, RUNX3-depleted LSECs secreted LRG1, which activated HSCs throughTGFBR1-SMAD2/3 signaling in a paracrine manner. Furthermore, circulating LRG1 levels were elevated in mouse models of liver fibrosis and in patients with fatty liver and cirrhosis. CONCLUSIONS: RUNX3 deficiency in the endothelium induces LSEC dysfunction, LRG1 secretion, and liver fibrosis progression. Therefore, endothelial RUNX3 is a crucial gatekeeping factor in LSECs, and profibrotic angiocrine LRG1 may be a novel target for combating liver fibrosis.
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Cancer cells use multiple mechanisms to evade the effects of glutamine metabolism inhibitors. The pathways that govern responses to alterations in glutamine availability within the tumor may represent therapeutic targets for combinatorial strategies with these inhibitors. Here, we showed that targeting glutamine utilization stimulated Yes-associated protein (YAP) signaling in cancer cells by reducing cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)-dependent phosphorylation of large tumor suppressor (LATS). Elevated YAP activation induced extracellular matrix (ECM) deposition by increasing secretion of connective tissue growth factor (CTGF) that promoted production of fibronectin and collagen by surrounding fibroblasts. Consequently, inhibiting YAP synergized with inhibition of glutamine utilization to effectively suppress tumor growth in vivo, along with a concurrent decrease in ECM deposition. Blocking ECM remodeling also augmented the tumor suppressive effects of the glutamine utilization inhibitor. Collectively, these data reveal mechanisms by which targeting glutamine utilization increases ECM accumulation and identify potential strategies to reduce ECM levels and increase the efficacy of glutamine metabolism inhibitors.
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BACKGROUND: Classically activated M1 macrophages, characterized by aberrant glycolysis and secretion of inflammatory cytokines, play pivotal roles in inflammatory diseases, including inflammatory bowel disease (IBD). Recently, sodium-glucose co-transporter 2 (SGLT2) inhibitors were shown to suppress Na+/H+ exchanger 1 (NHE1) and Na+/Ca2+ exchanger 1 (NCX1) activity, regulating downstream intracellular Ca2+ concentrations in cardiomyocytes. However, whether SGLT2 inhibitors regulate M1 macrophage polarization by downregulating NHE1 and NCX1 remains unknown. METHODS: We analyzed cellular responses to SGLT2 inhibitors using mouse bone marrow-derived macrophages and peritoneal macrophages treated with lipopolysaccharide (LPS). To induce IBD, we used a dextran sulfate sodium salt-induced colitis mouse model. RESULTS: We observed that NHE1 and NCX1 were overexpressed in LPS-treated macrophages, leading to M1 macrophage polarization. Mechanistically, NHE1 and NCX1-mediated Ca2+ accumulation in the macrophage resulted in enhanced glycolysis by promoting PI3K/AKT/mTORC1 signaling. SGLT2 inhibitors suppressed both the expression levels and activities of NHE1 and NCX1, and consequently downregulated PI3K/AKT/mTORC1 signaling and glycolysis in LPS-treated macrophages. We observed inhibition of LPS-stimulated M1 polarization and cytokine production by SGLT2 inhibitors in vitro, ex vivo, and in an IBD mouse model. CONCLUSIONS: NHE1 promotes M1 macrophage polarization and SGLT2 inhibitors are a novel strategy to treat M1 macrophage-mediated inflammatory diseases, including IBD.
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Doenças Inflamatórias Intestinais , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Camundongos , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Macrófagos/metabolismo , Modelos Animais de Doenças , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismoRESUMO
Macrophages within the tumor microenvironment (TME), referred to as tumor-associated macrophages (TAMs), are involved in various aspects of tumor progression including initiation, angiogenesis, metastasis, immunosuppression, and resistance to therapy. Myriocin, a natural compound isolated from Mycelia sterilia, is an immunosuppressant that inhibits tumor growth and angiogenesis. However, the mechanisms underlying the effects of myriocin on TAMs and TAM-mediated tumor growth have not yet been elucidated. In this study, we determined the effects of myriocin on TAMs and the underlying mechanism in vitro and in vivo. Myriocin significantly suppressed monocyte-macrophage differentiation and M2 polarization of macrophages but not M1 polarization. In addition, myriocin inhibited the expression of anti-inflammatory cytokines and secretion of proangiogenic factors, such as vascular endothelial growth factor, in M2 macrophages as well as M2-induced endothelial cell permeability. Myriocin also inhibited the PI3K/Akt/mTOR signaling pathway in M2 macrophages. Myriocin reduced the population of M2-like TAMs within the tumor tissue of a mouse allograft tumor model but not that of M1-like TAMs. Moreover, combined treatment with myriocin and cisplatin synergistically suppressed tumor growth and enhanced survival rate in mice by reducing the population of M2-like TAMs. Overall, these results suggest that myriocin inhibits tumor growth by remodeling the TME through suppression of differentiation and polarization of M2-like TAMs via the PI3K/Akt/mTOR signaling pathway.
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Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Serina-Treonina Quinases TOR/metabolismo , Macrófagos , Microambiente TumoralRESUMO
The renin-angiotensin (RA) system has been implicated in lung tumorigenesis without detailed mechanistic elucidation. Here, we demonstrate that exposure to the representative tobacco-specific carcinogen nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) promotes lung tumorigenesis through deregulation of the pulmonary RA system. Mechanistically, NNK binding to the nicotinic acetylcholine receptor (nAChR) induces Src-mediated signal transducer and activator of transcription 3 (STAT3) activation, resulting in transcriptional upregulation of angiotensinogen (AGT) and subsequent induction of the angiotensin II (AngII) receptor type 1 (AGTR1) signaling pathway. In parallel, NNK concurrently increases insulin-like growth factor 2 (IGF2) production and activation of IGF-1R/insulin receptor (IR) signaling via a two-step pathway involving transcriptional upregulation of IGF2 through STAT3 activation and enhanced secretion from intracellular storage through AngII/AGTR1/PLC-intervened calcium release. NNK-mediated crosstalk between IGF-1R/IR and AGTR1 signaling promoted tumorigenic activity in lung epithelial and stromal cells. Lung tumorigenesis caused by NNK exposure or alveolar type 2 cell-specific Src activation was suppressed by heterozygous Agt knockout or clinically available inhibitors of the nAChR/Src or AngII/AGTR1 pathways. These results demonstrate that NNK-induced stimulation of the lung RA system leads to IGF2-mediated IGF-1R/IR signaling activation in lung epithelial and stromal cells, resulting in lung tumorigenesis in smokers.
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Neoplasias Pulmonares , Nitrosaminas , Receptores Nicotínicos , Carcinógenos/toxicidade , Nicotiana/metabolismo , Nitrosaminas/toxicidade , Nitrosaminas/metabolismo , Receptores Nicotínicos/metabolismo , Sistema Renina-Angiotensina , Fator de Transcrição STAT3/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Transdução de Sinais , Pulmão/metabolismo , CarcinogêneseRESUMO
BACKGROUND: Chaperon-mediated autophagy (CMA) has taken on a new emphasis in cancer biology. However, the roles of CMA in hypoxic tumours are poorly understood. We investigated the anti-tumour effects of the natural product ManA through the activation of CMA in tumour progression under hypoxia. METHODS: The effect of ManA on CMA activation was assessed in mouse xenograft models and cells. The gene expressions of HIF-1α, HSP90AA1, and transcription factor EB (TFEB) were analysed using The Cancer Genome Atlas (TCGA) datasets to assess the clinical relevance of CMA. RESULTS: ManA activates photoswitchable CMA reporter activity and inhibits Hsp90 chaperone function by disrupting the Hsp90/F1F0-ATP synthase complex. Hsp90 inhibition enhances the interaction between CMA substrates and LAMP-2A and TFEB nuclear localisation, suggesting CMA activation by ManA. ManA-activated CMA retards tumour growth and displays cooperative anti-tumour activity with anti-PD-1 antibody. TCGA datasets show that a combined expression of HSP90AA1High/HIF1AHigh or TFEBLow/HIF1AHigh is strongly correlated with poor prognosis in patients with lung cancer. CONCLUSIONS: ManA-induced CMA activation by modulating Hsp90 under hypoxia induces HIF-1α degradation and reduces tumour growth. Thus, inducing CMA activity by targeting Hsp90 may be a promising therapeutic strategy against hypoxic tumours.
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Autofagia Mediada por Chaperonas , Neoplasias Pulmonares , Camundongos , Animais , Humanos , Hipóxia , Proteínas de Choque Térmico HSP90/metabolismo , Chaperonas Moleculares , Autofagia/genéticaRESUMO
Androgen deprivation therapy (ADT) is a systemic therapy for advanced prostate cancer (PCa); although most patients initially respond to ADT, almost all cancers eventually develop castration-resistant PCa (CRPC). Currently, most research focuses on castration-resistant tumors, and the role of tumors in remission is almost completely ignored. Here, we report that odorant-binding protein (OBP2A) released from tumors in remission during ADT catches survival factors, such as CXCL15/IL8, to promote PCa cell androgen-independent growth and enhance the infiltration of myeloid-derived suppressor cells (MDSCs) into tumor microenvironment, leading to the emergence of castration resistance. OBP2A knockdown significantly inhibits CRPC and metastatic CRPC development and improves therapeutic efficacy of CTLA-4/PD-1 antibodies. Treatment with OBP2A-binding ligand α-pinene interrupts the function of OBP2A and suppresses CRPC development. Furthermore, α-pinene-conjugated doxorubicin/docetaxel can be specifically delivered to tumors, resulting in improved anticancer efficacy. Thus, our studies establish a novel concept for the emergence of PCa castration resistance and provide new therapeutic strategies for advanced PCa.
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Antagonistas de Androgênios , Androgênios , Monoterpenos Bicíclicos , Resistencia a Medicamentos Antineoplásicos , Lipocalinas , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Antagonistas de Androgênios/uso terapêutico , Androgênios/deficiência , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos , Microambiente Tumoral , Monoterpenos Bicíclicos/uso terapêutico , Lipocalinas/genética , Lipocalinas/metabolismo , Linhagem Celular Tumoral , Animais , Camundongos , Anticorpos/uso terapêutico , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Inibidores de Checkpoint Imunológico/uso terapêuticoRESUMO
PURPOSE: Tumor microenvironment consists of various kind of cells, forming complex interactions and signal transductions for tumor growth. Due to this complexity, targeting multiple kinases could yield improved clinical outcomes. In this study, we aimed to investigate the potential of myriocin, from Mycelia sterilia, as a novel dual-kinase inhibitor and suggest myriocin as a candidate for combined chemotherapy. METHODS: We initially evaluated the anti-tumor and anti-metastatic effect of myriocin in mouse allograft tumor models. We examined the effects of myriocin on angiogenesis and tumor vasculature using in vitro, in vivo, and ex vivo models, and also tested the anti-migration effect of myriocin in in vitro models. Next, we explored the effects of myriocin alone and in combination with cisplatin on tumor growth and vascular normalization in mouse models. RESULTS: We found that myriocin inhibited tumor growth and lung metastasis in mouse allograft tumor models. Myriocin induced normalization of the tumor vasculature in the mouse models. We also found that myriocin suppressed angiogenesis through the VEGFR2/PI3K/AKT pathway in endothelial cells (ECs), as well as cancer cell migration by blocking the IκBα/NF-κB(p65)/MMP-9 pathway. Finally, we found that myriocin enhanced the drug delivery efficacy of cisplatin by increasing the integrity of tumor vasculature in the mouse models, which synergistically increased the anti-tumor activity of cisplatin. CONCLUSION: We suggest that myriocin is a novel potent anti-cancer agent that dually targets both VEGFR2 in ECs and IκBα in cancer cells, and exerts more pronounced anti-tumor effects than with either kinase being inhibited alone.
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Cisplatino , Neoplasias Pulmonares , Camundongos , Animais , Cisplatino/farmacologia , Inibidor de NF-kappaB alfa , Células Endoteliais , Fosfatidilinositol 3-Quinases , Proliferação de Células , Neovascularização Patológica , Linhagem Celular Tumoral , Microambiente TumoralRESUMO
BACKGROUND: Hypoxia is a characteristic feature of many solid tumors. As an adaptive response to hypoxia, tumor cells activate hypoxia-inducible factor-1α (HIF-1α). Under hypoxic conditions, angiogenesis mediated by HIF-1α is involved in the growth and metastasis of tumor cells. During the angiogenic process, differentiated tip endothelial cells (ECs) characterized by high expression of DLL4 promote angiogenic germination through filopodia. Inhibitors of HIF-1α or DLL4 have been widely studied PURPOSE: We tried to find inhibitors targeting both HIF-1α and DLL4 in tumor which have not yet been developed. STUDY DESIGN: In this study, we examined a natural compound that inhibits sprouting angiogenesis and tumor growth by targeting both HIF-1α and DLL4 under hypoxic conditions. METHODS: After examining cell viability of 70 selected natural compounds, we assessed the effects of compounds on HIF-1α and DLL4 transcriptional activity using a dual-luciferase reporter assay. Western blot analysis, immunofluoresecnt assay and real-time qPCR were performed to identify expression of proteins, such as HIF-1α and DLL4, as well as HIF-1α target genes under hypoxic conditions. In vitro angiogenesis assay and in vivo allograft tumor experiment were performed to investigate inhibition of tumor growth through anti-angiogenic activity. RESULTS: Among these compounds, steppogenin, which is extracted from the root bark of Morus alba l, respectively inhibited the transcriptional activity of HIF-1α under hypoxic conditions in HEK293T cells and vascular endothelial growth factor (VEGF)-induced DLL4 expression in vascular ECs in a dose-dependent manner. In tumor cells and retinal pigment epithelial cells, steppogenin significantly suppressed HIF-1α protein levels under hypoxic conditions as well as VEGF-induced DLL4 expression in ECs. Furthermore, steppogenin suppressed hypoxia-induced vascular EC proliferation and migration as well as VEGF-induced sprouting of EC spheroids. CONCLUSION: These results suggest that the natural compound steppogenin could potentially be used to treat angiogenic diseases, such as those involving solid tumors, because of its dual inhibition of HIF-1α and DLL4.
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Neoplasias , Fator A de Crescimento do Endotélio Vascular , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Hipóxia Celular , Linhagem Celular Tumoral , Células Endoteliais/metabolismo , Endotélio/metabolismo , Endotélio/patologia , Células HEK293 , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
The tumor microenvironment (TME) is broadly implicated in tumorigenesis, as tumor cells interact with surrounding cells to influence the development and progression of the tumor. Blood vessels are a major component of the TME and are attributed to the creation of a hypoxic microenvironment, which is a common feature of advanced cancers and inflamed premalignant tissues. Runt-related transcription factor (RUNX) proteins, a transcription factor family of developmental master regulators, are involved in vital cellular processes such as differentiation, proliferation, cell lineage specification, and apoptosis. Furthermore, the RUNX family is involved in the regulation of various oncogenic processes and signaling pathways as well as tumor suppressive functions, suggesting that the RUNX family plays a strategic role in tumorigenesis. In this review, we have discussed the relevant findings that describe the crosstalk of the RUNX family with the hypoxic TME and tumor angiogenesis or with their signaling molecules in cancer development and progression.
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Subunidades alfa de Fatores de Ligação ao Core , Neoplasias , Carcinogênese , Subunidades alfa de Fatores de Ligação ao Core/genética , Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Humanos , Hipóxia , Morfogênese , Neoplasias/genética , Neovascularização Patológica , Fatores de Transcrição/fisiologia , Microambiente TumoralRESUMO
Cancer creates a complex tumor microenvironment (TME) composed of immune cells, stromal cells, blood vessels, and various other cellular and extracellular elements. It is essential for the development of anti-cancer combination therapies to understand and overcome this high heterogeneity and complexity as well as the dynamic interactions between them within the TME. Recent treatment strategies incorporating immune-checkpoint inhibitors and anti-angiogenic agents have brought many changes and advances in clinical cancer treatment. However, there are still challenges for immune suppressive tumors, which are characterized by a lack of T cell infiltration and treatment resistance. In this review, we will investigate the crosstalk between immunity and angiogenesis in the TME. In addition, we will look at strategies designed to enhance anti-cancer immunity, to convert "immune suppressive tumors" into "immune activating tumors," and the mechanisms by which these strategies enhance effector immune cell infiltration.
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Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/patologia , Microambiente Tumoral/fisiologiaRESUMO
Background/Aims: Angiogenesis is essential for the outgrowth and metastasis of tumors. The structure and characteristics of tumor vasculature differ from those of normal vessels. We compared the characteristics of differentially expressed genes in endothelial cells (ECs) isolated from gastric and normal cells. Methods: Previously, we had isolated pure tumor ECs (TECs) and normal ECs (NECs) from advanced gastric cancer (AGC) lesions and normal mucosal tissues, respectively. Using the oligomer chip platform of the Affymetrix GeneChip technology, genes that were expressed more than three-fold with a significance of p≤0.001 were measured. The intercellular adhesion molecule 1 (ICAM-1) was found to be overexpressed in the TECs compared to the normal gastric ECs. In this study, the upregulation of ICAM-1 was confirmed in cultured TECs by immunofluorescence. Results: The expression of ICAM-1 was upregulated in the ECs, as well as in the stromal and immune cells, in early human gastric preneoplastic and hepatic fibrotic tissues. Upregulation of ICAM-1 was observed in the TECs, immune cells, and cancer epithelial cells in AGC and hepatocellular carcinoma (HCC). These results suggest that increased ICAM-1 expression in the ECs of the tissue microenvironment progressively contributes to the recruitment of immune cells to promote inflammation, leading to fibrosis and tumorigenesis. Conclusions: Therefore, upregulated ICAM-1 in the tissues in premalignant gastric diseases or hepatic fibrosis and their malignant cancers could be a promising target for disease prevention and treatment.
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Carcinoma Hepatocelular , Endotélio Vascular , Molécula 1 de Adesão Intercelular , Neoplasias Hepáticas , Neoplasias Gástricas , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Microambiente TumoralRESUMO
Although shed syndecan-2 potentiated the tumorigenic activities of colon cancer cells, how shed syndecan-2 increases this tumorigenic potential remains unclear. Using an orthotopic mouse model of colon cancer, we show that shed syndecan-2 increases colon cancer progression by cooperatively promoting angiogenesis. Co-administration with a synthetic peptide of shed syndecan-2 (S2LQ) enhanced the survival and tumor engraftment of luciferase-expressing CT26 colon adenocarcinoma cells orthotopically implanted into the cecum of BALB/c mice. Intravenous injection of S2LQ further enhanced the growth of orthotopic tumors in the cecum, with increases in the tissue infiltration of macrophages and the formation of blood vessels, mainly in peripheral layers of the tumor facing the stroma. Furthermore, S2LQ stabilized HIF1α and enhanced the VEGF expression in human colon cancer cell lines, and increased the migration of RAW 264.7 murine macrophage cells and bone marrow-derived macrophages. Finally, S2LQ increased the tube formation of vascular endothelial cells in vitro. Together, these data demonstrate that shed syndecan-2 enhances tumorigenic activity by increasing the crosstalk of cancer cells with tumor-associated macrophages and endothelial cells to enhance angiogenesis for colon cancer progression in the tumor microenvironment.
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Neoplasias do Colo , Sindecana-2 , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Progressão da Doença , Células Endoteliais/metabolismo , Camundongos , Neovascularização Patológica/metabolismo , Sindecana-2/genética , Sindecana-2/metabolismo , Microambiente TumoralRESUMO
RNA polymerase II (Pol II)-dependent transcription in stimulus-inducible genes requires topoisomerase IIß (TOP2B)-mediated DNA strand break and the activation of DNA damage response signalling in humans. Here, we report a novel function of the breast cancer 1 (BRCA1)-BRCA1-associated ring domain 1 (BARD1) complex in this process. We found that BRCA1 is phosphorylated at S1524 by the kinases ataxia-telangiectasia mutated and ATR during gene activation, and that this event is important for productive transcription. Our biochemical and genomic analyses showed that the BRCA1-BARD1 complex interacts with TOP2B in the EGR1 transcription start site and in a large number of protein-coding genes. Intriguingly, the BRCA1-BARD1 complex ubiquitinates TOP2B, which stabilizes TOP2B binding to DNA while BRCA1 phosphorylation at S1524 controls the TOP2B ubiquitination by the complex. Together, these findings suggest the novel function of the BRCA1-BARD1 complex in the regulation of TOP2B and Pol II-mediated gene expression.
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Proteína BRCA1/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Proteínas Imediatamente Precoces/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína BRCA1/química , Proteína 1 de Resposta de Crescimento Precoce/genética , Regulação da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Mutação , Fosforilação , Sítio de Iniciação de Transcrição , Transcrição Gênica , UbiquitinaçãoRESUMO
Epstein-Barr-virus-associated gastric carcinoma (EBVaGC), first reported in 1992, currently accounts for 10% of all gastric carcinoma worldwide. EBVaGC has unique DNA hypermethylation phenotypes that allow for higher proportions of DNA methylation than any other gastric cancer. CpG islands in the gene promoter region are one of the major regions in which DNA methylation controls gene transcription. Despite cisplatin-based chemotherapy being one of the standard treatment regimens for advanced gastric cancer, including EBVaGC, cisplatin alone or in combination with 5-fluorouracil has been limited by its less potent anticancer activity and the occurrence of cisplatin resistance. Accordingly, the current study evaluated the anticancer activities of a combination of cisplatin and 5-Azacytidine (5-AZA) against EBVaGC. Our findings showed that cisplatin upregulated the DNMT3A gene, whereas shRNA-targeted removal of DNMT3A mRNA contributed to cisplatin-mediated EBV lytic reactivation. Moreover, the removal of DNMT3A mRNA upregulated the ATM gene through DNA demethylation on the ATM promoter. Furthermore, CRISPR/Cas9-targeted removal of the ATM gene resulted in significantly reduced cell susceptibility and EBV lytic reactivation by a combination of cisplatin and DNMT3A inhibitor 5-AZA. Finally, 5-AZA exhibited a synergistic effect with cisplatin in anti-EBV and anti-EBVaGC activities by increasing drug susceptibility and EBV lytic reactivation. The aforementioned results suggest that cisplatin combined with DNA methylation inhibitors could be a novel therapeutic approach for EBVaGC.
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Inactivation of tumor suppressor Runt-related transcription factor 3 (RUNX3) plays an important role during early tumorigenesis. However, posttranslational modifications (PTM)-based mechanism for the inactivation of RUNX3 under hypoxia is still not fully understood. Here, we demonstrate a mechanism that G9a, lysine-specific methyltransferase (KMT), modulates RUNX3 through PTM under hypoxia. Hypoxia significantly increased G9a protein level and G9a interacted with RUNX3 Runt domain, which led to increased methylation of RUNX3 at K129 and K171. This methylation inactivated transactivation activity of RUNX3 by reducing interactions with CBFß and p300 cofactors, as well as reducing acetylation of RUNX3 by p300, which is involved in nucleocytoplasmic transport by importin-α1. G9a-mediated methylation of RUNX3 under hypoxia promotes cancer cell proliferation by increasing cell cycle or cell division, while suppresses immune response and apoptosis, thereby promoting tumor growth during early tumorigenesis. Our results demonstrate the molecular mechanism of RUNX3 inactivation by G9a-mediated methylation for cell proliferation and antiapoptosis under hypoxia, which can be a therapeutic or preventive target to control tumor growth during early tumorigenesis.
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Carcinogênese/genética , Hipóxia Celular/genética , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Metilação de DNA/genética , Acetilação , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The role of angiogenesis in the growth of organs and tumors is widely recognized. Vascular-organ interaction is a key mechanism and a concept that enables an understanding of all biological phenomena and normal physiology that is essential for human survival under pathological conditions. Recently, vascular endothelial cells have been classified as a type of innate immune cells that are dependent on the pathological situations. Moreover, inflammatory cytokines and signaling regulators activated upon exposure to infection or various stresses play crucial roles in the pathological function of parenchymal cells, peripheral immune cells, stromal cells, and cancer cells in tissues. Therefore, vascular-organ interactions as a vascular microenvironment or tissue microenvironment under physiological and pathological conditions are gaining popularity as an interesting research topic. Here, we review vascular contribution as a major factor in microenvironment homeostasis in the pathogenesis of normal as well as cancerous tissues. Furthermore, we suggest that the normalization strategy of pathological angiogenesis could be a promising therapeutic target for various diseases, including cancer.
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Inibidores da Angiogênese/uso terapêutico , Endotélio Vascular/patologia , Neoplasias/tratamento farmacológico , Neovascularização Patológica/imunologia , Inibidores da Angiogênese/farmacologia , Animais , Citocinas/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Neoplasias/irrigação sanguínea , Neoplasias/imunologia , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologiaRESUMO
BACKGROUND: Conventional therapeutic approaches for tumor angiogenesis, which are primarily focused on the inhibition of active angiogenesis to starve cancerous cells, target the vascular endothelial growth factor signaling pathway. This aggravates hypoxia within the tumor core and ultimately leads to increased tumor proliferation and metastasis. To overcome this limitation, we developed nanoparticles with antiseptic activity that target tumor vascular abnormalities. METHODS: Ferritin-based protein C nanoparticles (PCNs), known as TFG and TFMG, were generated and tested in Lewis lung carcinoma (LLC) allograft and MMTV-PyMT spontaneous breast cancer models. Immunohistochemical analysis was performed on tumor samples to evaluate the tumor vasculature. Western blot and permeability assays were used to explore the role and mechanism of the antitumor effects of PCNs in vivo. For knocking down proteins of interest, endothelial cells were transfected with siRNAs. Statistical analysis was performed using one-way ANOVA followed by post hoc Dunnett's multiple comparison test. RESULTS: PCNs significantly inhibited hypoxia and increased pericyte coverage, leading to the inhibition of tumor growth and metastasis, while increasing survival in LLC allograft and MMTV-PyMT spontaneous breast cancer models. The coadministration of cisplatin with PCNs induced a synergistic suppression of tumor growth by improving drug delivery as evidenced by increased blood prefusion and decreased vascular permeability. Moreover, PCNs altered the immune cell profiles within the tumor by increasing cytotoxic T cells and M1-like macrophages with antitumor activity. PCNs induced PAR-1/PAR-3 heterodimerization through EPCR occupation and PAR-1 activation, which resulted in Gα13-RhoA-mediated-Tie2 activation and stabilized vascular tight junctions via the Akt-FoxO3a signaling pathway. CONCLUSIONS: Cancer treatment targeting the tumor vasculature by inducing antitumor immune responses and enhancing the delivery of a chemotherapeutic agent with PCNs resulted in tumor regression and may provide an effective therapeutic strategy.
Assuntos
Apoferritinas/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Neoplasias Mamárias Experimentais/tratamento farmacológico , Nanopartículas/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Proteína C/uso terapêutico , Receptor TIE-2/fisiologia , Remodelação Vascular/efeitos dos fármacos , Inibidores da Angiogênese/uso terapêutico , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/uso terapêutico , Apoferritinas/administração & dosagem , Bevacizumab/uso terapêutico , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Carcinoma Pulmonar de Lewis/patologia , Hipóxia Celular/efeitos dos fármacos , Cisplatino/administração & dosagem , Cisplatino/uso terapêutico , Técnicas de Cocultura , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Células Endoteliais/efeitos dos fármacos , Feminino , Masculino , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas de Neoplasias/fisiologia , Pericitos/metabolismo , Proteína C/administração & dosagem , Organismos Livres de Patógenos Específicos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologiaRESUMO
BACKGROUND: Hypoxia and HIF-1α are important regulators of tumour growth and angiogenesis and could be attractive targets for cancer therapeutics. Decursin is an active compound extracted from the roots of Angelica gigas and has been shown to have potent anti-cancer and anti-angiogenic activities. However, whether decursin regulates HIF-1α activity and immune responses under hypoxic conditions is not yet understood. PURPOSE: The aim of this study was to identify whether decursin exhibits anti-cancer activity by targeting HIF-1α. STUDY DESIGN: We investigated whether decursin regulates HIF-1α protein stability and increases its degradation. In addition, we determined if decursin increases immune responses in tumour microenvironment to identify its hypoxia-associated anti-cancer activities. MATERIALS AND METHODS: We performed the hypoxia-responsive element promoter-reporter assay, Western blot analysis, immune-fluorescence assay, semi-quantitative RT-PCR and ELISA for VEGF secretion, CCK-8 assay for cell proliferation, TUNEL assay for apoptosis and invasion assay in A549 human lung cancer or HCT116 human colon cancer cells. In vivo Lewis lung carcinoma (LLC) allograft mouse model was used to check tumour growth and immune responses in tumour microenvironment by immunohistochemistry analysis. RESULTS: We observed that decursin inhibited HIF-1 activation under hypoxia by down-regulating the protein level of its subunit HIF-1α. It increased oxygen-dependant hydroxylation and ubiquitination of HIF-1α to promote HIF-1α degradation. Decursin also decreased mRNA expression of HIF-1α target genes. Decursin suppressed cancer cell proliferation, induced apoptosis and inhibited cancer cell invasion under hypoxia in cancer cells. In the allograft mouse tumour model, decursin reduced the hypoxic area and HIF-1α and PD-L1 expression. Infiltrating T cells (CD3+), helper T cells (CD4+) and cytotoxic (CD8+) T cells were accumulated, but regulatory T cells (Foxp3) and myeloid-derived suppressor cell-mediated immune suppressors (Arg1) were attenuated by decursin. CONCLUSION: Our results suggest that decursin is a novel HIF-1α inhibitor that functions by promoting its proteasomal degradation and that it also helps improve T cell activation in tumour microenvironment; these findings provide new explanations about its anti-cancer and anti-angiogenic activity mechanisms.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzopiranos/farmacologia , Butiratos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Células A549 , Animais , Apoptose/efeitos dos fármacos , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Humanos , Camundongos Endogâmicos C57BL , Hipóxia Tumoral/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Tumors adapt to hypoxia by regulating angiogenesis, metastatic potential, and metabolism. These adaptations mediated by hypoxia-inducible factor 1 (HIF-1) make tumors more aggressive and resistant to chemotherapy and radiation. Therefore, HIF-1 is a validated therapeutic target for cancer. In order to develop new HIF-1 inhibitors for cancer chemotherapy by harnessing the potential of the natural product manassantin A, we synthesized and evaluated manassantin A analogues with modifications in the tetrahydrofuran core region of manassantin A. Our structure-activity relationship study indicated that the α,α'-trans-configuration of the central ring of manassantin A is critical to HIF-1 inhibition. We also demonstrated that a combination of manassantin A with an epidermal growth factor receptor inhibitor shows cooperative antitumor activity (â¼80% inhibition for combination vs â¼30% inhibition for monotherapy). Our findings will provide important frameworks for the future therapeutic development of manassantin A-derived chemotherapeutic agents.