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1.
Biochem Biophys Res Commun ; 583: 56-62, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34735880

RESUMO

Itaconic acid is an unsaturated dicarbonic acid. It has a wide range of applications in the industrial production of resins and is also a mediator of immunometabolism in macrophages. Here, we show a previously unrecognized role of itaconic acid in triggering ferroptosis, a form of iron-dependent cell death driven by lipid peroxidation. We found that supraphysiological itaconic acid dose-dependently induces ferroptosis, rather than apoptosis, in human cancer cell lines. Mechanistically, we determined that itaconic acid activates NOCA4-mediated ferritinophagy, which leads to ferroptosis through ferritin degradation and subsequent iron overload and oxidative damage. In contrast, itaconic acid-induced expression and activation of NFE2L2 serves as a defense mechanism to limit ferroptosis by producing antioxidant genes. Consequently, impaired NCOA4 expression prevented, whereas a disrupted NFE2L2 pathway enhanced, sensitivity to itaconic acid-induced ferroptosis in vitro and in xenograft models. These findings establish a dynamic model of metabolite-induced ferroptotic cancer cell death, which may contribute to the development of new targeted therapies.

2.
Biochem Biophys Res Commun ; 576: 33-39, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34478917

RESUMO

Dendritic cells (DCs) are antigen-presenting cells of the immune system, which play a key role in antitumor immunity by activating cytotoxic T cells. Here, we report that elevated ferroptosis, a lipid peroxidation-mediated cell death, impairs the maturation of DCs and their function in tumor suppression. Ferroptosis is selectively induced in DCs by the GXP4 inhibitor RSL3, but not the SLC7A11 inhibitor erastin. Ferroptotic DCs lose their ability to secrete pro-inflammatory cytokines (TNF and IL6) and express MHC class I in response to the maturation signal of lipopolysaccharide. Moreover, ferroptotic DCs fail to induce CD8+ T cells to produce IFNG/IFNγ. Mechanistically, PPARG/PPARγ, a nuclear receptor involved in the regulation of lipid metabolism, is responsible for RSL3-induced ferroptosis in DCs. Consequently, the genetic depletion of PPARG restores the maturation and function of DCs. Using immunogenic cell death-based DC vaccine models, we further demonstrate that PPARG-mediated ferroptosis of DCs limits antitumor immunity in mice. Together, these findings demonstrate a novel role of ferroptotic DCs in driving an immunosuppressive tumor microenvironment.

3.
Bioengineered ; 12(1): 4747-4756, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34334103

RESUMO

The aim of this study was to delve into the clinical significance and biological function of miR-2355-3p in LUAD. Tissues and blood samples from 116 LUAD patients and blood samples of 90 healthy volunteers were collected. The relative expression of miR-2355-3p was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). The receiver operating curve (ROC) was plotted for diagnostic value estimation. Kaplan-Meier survival curves were constructed, and multivariate survival analyses were performed for prognostic value estimation. A luciferase reporter assay was carried out to confirm the interaction of miR-2355-3p and ZCCHC14. The CCK-8 and transwell assays were conducted to explore the function of miR-2355-3p on LUAD cells. Rescue experiments were performed to verify the interaction. miR-2355-3p showed an upregulated expression in the samples of LUAD patients. For diagnostic value estimation, the AUC was 0.905 with a sensitivity was 84.5% and specificity of 83.3%. For the estimation of prognostic value, the P-value of log-rank test on K-M curves was 0.002 and 0.006 for overall survival and progression survival, respectively. Based on multivariate Cox regression analysis, miR-2355-3p was a powerful prognostic tool with a P-value of 0.027. ZCCHC14 has binding sites with miR-2355-3p, an expression level, and luciferase activity negatively correlated with miR-2355-3p expression. Knockdown of miR-2355-3p inhibited proliferation, migration, and invasion of LUAD cells, but ZCCHC14 can rescue this inhibition. miR-2355-3p has the potential to be a diagnostic marker and prognostic marker for LUAD. Inhibition of miR-2355-3p in LUAD cells can suppress the progression of LUAD at least partly by direct targeting ZCCHC14.

4.
Theranostics ; 11(14): 6668-6681, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093846

RESUMO

Background: Newly emerging cancer immunotherapy has led to significant progress in cancer treatment; however, its efficacy is limited in solid tumors since the majority of them are "cold" tumors. Oncolytic viruses, especially when properly armed, can directly target tumor cells and indirectly modulate the tumor microenvironment (TME), resulting in "hot" tumors. These viruses can be applied as a cancer immunotherapy approach either alone or in combination with other cancer immunotherapies. Cytokines are good candidates to arm oncolytic viruses. IL-23, an IL-12 cytokine family member, plays many roles in cancer immunity. Here, we used oncolytic vaccinia viruses to deliver IL-23 variants into the tumor bed and explored their activity in cancer treatment on multiple tumor models. Methods: Oncolytic vaccinia viruses expressing IL-23 variants were generated by homologue recombination. The characteristics of these viruses were in vitro evaluated by RT-qPCR, ELISA, flow cytometry and cytotoxicity assay. The antitumor effects of these viruses were evaluated on multiple tumor models in vivo and the mechanisms were investigated by RT-qPCR and flow cytometry. Results: IL-23 prolonged viral persistence, probably mediated by up-regulated IL-10. The sustainable IL-23 expression and viral oncolysis elevated the expression of Th1 chemokines and antitumor factors such as IFN-γ, TNF-α, Perforin, IL-2, Granzyme B and activated T cells in the TME, transforming the TME to be more conducive to antitumor immunity. This leads to a systemic antitumor effect which is dependent on CD8+ and CD4+ T cells and IFN-γ. Oncolytic vaccinia viruses could not deliver stable IL-23A to the tumor, attributed to the elevated tristetraprolin which can destabilize the IL-23A mRNA after the viral treatment; whereas vaccinia viruses could deliver membrane-bound IL-23 to elicit a potent antitumor effect which might avoid the possible toxicity normally associated with systemic cytokine exposure. Conclusion: Either secreted or membrane-bound IL-23-armed vaccinia virus can induce potent antitumor effects and IL-23 is a candidate cytokine to arm oncolytic viruses for cancer immunotherapy.


Assuntos
Adenocarcinoma/terapia , Neoplasias do Colo/terapia , Imunoterapia/métodos , Interleucina-23/farmacologia , Vírus Oncolíticos/genética , Microambiente Tumoral/imunologia , Vírus Vaccinia/genética , Adenocarcinoma/imunologia , Adenocarcinoma/virologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Neoplasias do Colo/imunologia , Neoplasias do Colo/virologia , Modelos Animais de Doenças , Feminino , Vetores Genéticos , Granzimas/metabolismo , Humanos , Interferon gama/metabolismo , Interleucina-12/metabolismo , Interleucina-2/metabolismo , Interleucina-23/genética , Interleucina-23/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Vírus Oncolíticos/metabolismo , Perforina/metabolismo , Microambiente Tumoral/genética , Fator de Necrose Tumoral alfa/metabolismo , Vírus Vaccinia/metabolismo
5.
Biochem Biophys Res Commun ; 567: 92-98, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34146907

RESUMO

Nonsense-mediated mRNA decay (NMD) is a quality control mechanism that plays an integral role in eliminating abnormal mRNA and corresponding proteins. It is unclear whether the NMD pathway is involved in regulating ferroptosis, which is a type of iron-dependent cell death mainly caused by the inhibition of the antioxidant SLC7A11-GPX4 axis. In this study, we conducted a small-scale RNAi screen and proved that SMG9, a component of the NMD machinery, is a selective driver for ferroptosis in human cancer cells. SMG9 positively regulates ferroptosis independent of its activity in NMD. Instead, SMG9 is a direct binding protein of GPX4 to promote the degradation of GPX4 in response to RSL3 (a GPX4 inhibitor), but not erastin (a SLC7A11 inhibitor). The genetic inhibition of SMG9 increases the accumulation of GPX4 in the mitochondria, thereby preventing mitochondrial oxidative damage, and ultimately favoring ferroptosis resistance in vitro or in xenograft mouse models. Overall, these findings establish a new mitochondrial regulation mechanism that can affect ferroptosis-mediated tumor suppression.


Assuntos
Ferroptose , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Linhagem Celular Tumoral , Humanos , Camundongos Nus , Proteólise
6.
Biochem Biophys Res Commun ; 560: 165-171, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-33992959

RESUMO

Alkaliptosis is a recently discovered form of regulated cell death driven by intracellular alkalization. However, the immune characteristics and mechanisms of alkaliptosis are still poorly understood. Here, we show that HMGB1, a multifunctional alarm protein that drives innate immunity, is necessary for inflammation caused by alkaliptotic damage. During alkaliptosis, HMGB1 translocation and release from the nucleus to the cytoplasm to the extracellular space requires nuclear DNA damage signals, whereas the FANCD2-dependent (but not ATM-mediated) DNA repair pathway inhibits this process. Once released by alkaliptotic cancer cells, extracellular HMGB1 binds to the AGER receptor in macrophages and then activates the STING1 pathway to produce pro-inflammatory cytokines (e.g., TNF and IL6). Consequently, the pharmacological or genetic inhibition of the HMGB1-AGER-STING1 pathway limits cytokine production during alkaliptosis. These findings provide new insight into the sterile inflammatory response to cell death.


Assuntos
Proteína HMGB1/metabolismo , Proteínas de Membrana/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Morte Celular Regulada , Animais , Linhagem Celular , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos Knockout , Transdução de Sinais
7.
Cancer Immunol Immunother ; 70(9): 2467-2481, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33538860

RESUMO

In this study, we aimed to apply the cytokine IL-36γ to cancer immunotherapy by constructing new oncolytic vaccinia viruses (OV) expressing interleukin-36γ (IL-36γ-OVs), leveraging unique synergism between OV and IL-36γ's ability to promote antitumor adaptive immunity and modulate tumor microenvironment (TME). IL-36γ-OV had dramatic therapeutic efficacies in multiple murine tumor models, frequently leading to complete cancer eradication in large fractions of mice. Mechanistically, IL-36-γ-armed OV induced infiltration of lymphocytes and dendritic cells, decreased myeloid-derived suppressor cells and M2-like tumor-associated macrophages, and T cell differentiation into effector cells. Further study showed that IL-36γ-OV increased the number of tumor antigen-specific CD4+ and CD8+ T cells and the therapeutic efficacy depended on both CD8+ and CD4+ T cells. These results demonstrate that these IL36γ-armed OVs exert potent therapeutic efficacy mainly though antitumor immunity and they may hold great potential to advance treatment in human cancer patients.


Assuntos
Imunidade Adaptativa , Terapia Genética , Vetores Genéticos/genética , Interleucina-1/genética , Neoplasias/imunologia , Neoplasias/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Citotoxicidade Imunológica , Modelos Animais de Doenças , Expressão Gênica , Engenharia Genética , Vetores Genéticos/administração & dosagem , Humanos , Melanoma Experimental , Camundongos , Imagem Molecular , Neoplasias/diagnóstico , Neoplasias/genética , Terapia Viral Oncolítica/efeitos adversos , Terapia Viral Oncolítica/métodos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Oncoimmunology ; 10(1): 1868691, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33489473

RESUMO

Drug-induced ferroptosis, an iron-dependent regulatory necrosis, has been proposed for the therapy of pancreatic ductal adenocarcinoma. However, genetically engineered mouse models have revealed that high-iron diets or deletion of pancreatic GPX4 (a key repressor of ferroptosis) accelerate the development of mutant Kras-driven PDAC by activating the STING1/TMEM173-dependent DNA sensor pathway. Abbreviations ADM: acinar-to-ductal metaplasia; CGAS: cyclic GMP-AMP synthase; DAMP: damage-associated molecular pattern; GPX4: glutathione peroxidase 4; GEMM: genetically engineered mouse models; PDAC: pancreatic ductal adenocarcinoma; PanIN: pancreatic intraepithelial neoplasia, SLC7A11: solute carrier family 7 member 11; STING1: cGAMP-stimulator of interferon response cGAMP interactor 1; TME: tumor microenvironment; 8-OHG: 8-hydroxy-2'-deoxyguanosine.


Assuntos
Carcinoma Ductal Pancreático , Ferroptose , Neoplasias Pancreáticas , Células Acinares , Animais , Carcinoma Ductal Pancreático/genética , Camundongos , Pâncreas , Neoplasias Pancreáticas/genética , Microambiente Tumoral
9.
Cancer Gene Ther ; 28(1-2): 98-111, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32632271

RESUMO

Adoptive cell therapy (ACT) using tumor-specific tumor-infiltrating lymphocytes (TILs) has demonstrated success in patients where tumor-antigen specific TILs can be harvested from the tumor, expanded, and re-infused in combination with a preparatory regimen and IL2. One major issue for non-immunogenic tumors has been that the isolated TILs lack tumor specificity and thus possess limited in vivo therapeutic function. An oncolytic virus (OV) mediates an immunogenic cell death for cancer cells, leading to elicitation and dramatic enhancement of tumor-specific TILs. We hypothesized that the tumor-specific TILs elicited and promoted by an OV would be a great source for ACT for solid cancer. In this study, we show that a local injection of oncolytic poxvirus in MC38 tumor with low immunogenicity in C57BL/6 mice, led to elicitation and accumulation of tumor-specific TILs in the tumor tissue. Our analyses indicated that IL2-armed OV-elicited TILs contain lower quantities of exhausted PD-1hiTim-3+ CD8+ T cells and regulatory T cells. The isolated TILs from IL2-expressing OV-treated tumor tissue retained high tumor specificity after expansion ex vivo. These TILs resulted in significant tumor regression and improved survival after adoptive transfer in mice with established MC38 tumor. Our study showcases the feasibility of using an OV to induce tumor-reactive TILs that can be expanded for ACT.

10.
Biochem Biophys Res Commun ; 536: 100-106, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33373853

RESUMO

In regulated cell death, genetically encoded molecular machinery destroys cells. This process is not only essential for organ development and homeostasis, but also leads to pathological diseases. One form of regulated cell death is ferroptosis, which is an iron-dependent oxidative cell death caused by lipid peroxidation. Although inducing ferroptosis is an emerging anticancer strategy, the molecular mechanism underlying tumor resistance to ferroptotic cell death is still unclear. Here, we show that pirin (PIR), an iron-binding nuclear protein, plays a previously unrecognized role in mediating ferroptosis resistance in human pancreatic cancer cells. The transcription factor NFE2L2 mediates the upregulation of PIR during ferroptosis caused by small-molecule compounds (e.g., erastin or RSL3). PIR is a nuclear redox sensor and regulator, and increasing it limits the oxidative damage of DNA and the subsequent cytoplasmic transport and extracellular release of HMGB1. In contrast, the depletion of PIR initiates HMGB1-dependent autophagy by binding to BECN1, and subsequently promotes ferroptosis by activating ACSL4. Consequently, in cell cultures and xenograft mouse models, blocking PIR signaling enhances ferroptosis-mediated tumor growth suppression. Together, these findings provide new insights into the molecular mechanisms of autophagy-dependent ferroptosis.


Assuntos
Autofagia , Núcleo Celular/metabolismo , Dioxigenases/metabolismo , Ferroptose , Animais , Linhagem Celular Tumoral , Coenzima A Ligases/metabolismo , Dioxigenases/genética , Proteína HMGB1/metabolismo , Humanos , Camundongos Nus , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Regulação para Cima/genética
11.
Nat Commun ; 11(1): 6339, 2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33311482

RESUMO

Ferroptosis is a more recently recognized form of cell death that relies on iron-mediated oxidative damage. Here, we evaluate the impact of high-iron diets or depletion of Gpx4, an antioxidant enzyme reported as an important ferroptosis suppressor, in the pancreas of mice with cerulean- or L-arginine-induced pancreatitis, and in an oncogenic Kras murine model of spontaneous pancreatic ductal adenocarcinoma (PDAC). We find that either high-iron diets or Gpx4 depletion promotes 8-OHG release and thus activates the TMEM173/STING-dependent DNA sensor pathway, which results in macrophage infiltration and activation during Kras-driven PDAC in mice. Consequently, the administration of liproxstatin-1 (a ferroptosis inhibitor), clophosome-mediated macrophage depletion, or pharmacological and genetic inhibition of the 8-OHG-TMEM173 pathway suppresses Kras-driven pancreatic tumorigenesis in mice. GPX4 is also a prognostic marker in patients with PDAC. These findings provide pathological and mechanistic insights into ferroptotic damage in PDAC tumorigenesis in mice.


Assuntos
Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Ferroptose/fisiologia , Proteínas de Membrana/metabolismo , Pâncreas/metabolismo , Animais , Biomarcadores Tumorais , Carcinogênese/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Morte Celular/fisiologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , DNA , Dieta , Modelos Animais de Doenças , Feminino , Ferroptose/efeitos dos fármacos , Humanos , Ferro/metabolismo , Macrófagos , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Pâncreas/patologia , Pancreatite/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Quinoxalinas/farmacologia , Compostos de Espiro/farmacologia , Microambiente Tumoral
12.
DNA Cell Biol ; 39(10): 1825-1837, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32799546

RESUMO

The objective of this study was to identify the key circular RNAs (circRNAs) related to the development of colon cancer. High-throughput RNA sequencing on eight early-stage (ES) and eight later stage (LS) colon tumor tissues, and eight normal tissues, was performed. Differentially expressed circRNAs and differentially expressed mRNAs were identified. Functional enrichment analysis and the miRNA-circRNA-mRNA network were performed. In addition, the differential expression levels of key circRNAs were verified using real-time quantitative PCR (qPCR). In total, 408, 472, and 278 differentially expressed circRNAs were identified in ES versus normal control (N), LS versus N, and LS versus ES groups, respectively. Functional enrichment analysis showed that circ_052666 was significantly enriched in "extracellular matrix/receptor interaction"; circ_022743 was remarkably enriched in "neurotrophin signaling pathway"; and circ_004452 was observably enriched in "TGF-ß signaling pathway." Moreover, key miRNA-circRNA-mRNA relationships, such as hsa-miR-29b/c-3p-circ_052666-COL1A1 and hsa-miR-1294-circ_004452-left-right determination factor 1 (LEFTY1), were identified. Furthermore, qPCR showed consistent results with RNA sequencing. Our findings indicate that key circRNAs, such as circ_022743, circ_052666, and circ_004452, may be involved in colon cancer development, and could be used as potential biomarkers for the diagnosis and treatment of this disease.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , RNA Circular/genética , Transcriptoma , Idoso , Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Redes Reguladoras de Genes , Humanos , Masculino , Pessoa de Meia-Idade , RNA Circular/metabolismo
14.
Mol Ther Oncolytics ; 17: 350-360, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32405533

RESUMO

Successful in situ therapeutic vaccination would allow locally delivered oncolytic virus (OV) to exert systemic immunologic effects on metastases and improve survival. We have utilized bilateral flank tumor models to determine the most efficacious regimens of in situ vaccination. Intratumoral injection with membrane-tethered interleukin -2-armed OV (vvDD-mIL2) plus a Toll-like receptor 9 ligand (CpG) yielded systemic immunization and decreased tumor growth in a contralateral, noninjected tumor. Our main aims were to study the tumor immune microenvironment (TME) after vaccination and identify additional immune adjuvants that may improve the systemic tumor-specific immunity. Immunological profiles in the spleen showed an increased CD8+ T cell/regulatory T cell (Treg) ratio and increased CD11c+ cells after dual injection in one flank tumor. Concurrently, there was increased infiltration of tumor necrosis factor alpha (TNF-α)+CD8+ T cells and interferon gamma (IFN-γ)+CD4+ T cells and reduced CTLA-4+PD-1+CD8+ T cells in the contralateral, noninjected tumor. The anti-tumoral activity depended on CD8+ T cells and IFN-γ, but not CD4+ T cells. Based on the negative immune components still existing in the untreated tumors, we investigated additional adjuvants: clodronate liposome-mediated depletion of macrophages plus anti-PD-1 therapy. This regimen dramatically reduced the tumor burden in the noninjected tumor and increased median survival by 87%, suggesting that inhibition/elimination of suppressive components in the tumor microenvironment (TME) can improve therapeutic outcomes. This study emphasizes the importance of immune profiling to design rational, combined immunotherapy regimens ultimately to impact patient survival.

15.
J Immunother Cancer ; 8(1)2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32209602

RESUMO

Immune checkpoint blockade is arguably the most effective current cancer therapy approach; however, its efficacy is limited to patients with "hot" tumors, warranting an effective approach to transform "cold" tumors. Oncolytic viruses (especially properly armed ones) have positive effects on almost every aspect of the cancer-immunity cycle and can change the cancer-immune set point of a tumor. Here, we tested whether oncolytic vaccinia virus delivering tethered interleukin 12 (IL-12) could turn a "cold" tumor into a "hot" tumor while avoiding IL-12's systemic toxicity. Our data demonstrated that tethered IL-12 could be maintained in the tumor without treatment-induced toxic side effects. Moreover, the treatment facilitated tumor infiltration of more activated CD4+ and CD8+ T cells and less Tregs, granulocytic myeloid-derivedsuppressor cells, and exhausted CD8+ T cells, with increased interferon γ and decreased transforming growth factor ß, cyclooxygenase-2, and vascular endothelial growth factor expression, leading to transformed, immunogenic tumors and improved survival. Combined with programmed cell death 1 blockade, vaccinia virus expressing tethered IL-12 cured all mice with late-stage colon cancer, suggesting immediate translatability to the clinic.


Assuntos
Citocinas/metabolismo , Imunoterapia/métodos , Interleucina-12/genética , Vírus Oncolíticos/genética , Vírus Vaccinia/genética , Animais , Vetores Genéticos , Humanos , Camundongos
16.
Autophagy ; 16(11): 2069-2083, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-31920150

RESUMO

KRAS is the most frequently mutated oncogene in human neoplasia. Despite a large investment to understand the effects of KRAS mutation in cancer cells, the direct effects of the oncogenetic KRAS activation on immune cells remain elusive. Here, we report that extracellular KRASG12D is essential for pancreatic tumor-associated macrophage polarization. Oxidative stress induces KRASG12D protein release from cancer cells succumbing to autophagy-dependent ferroptosis. Extracellular KRASG12D packaged into exosomes then is taken up by macrophages through an AGER-dependent mechanism. KRASG12D causes macrophages to switch to an M2-like pro-tumor phenotype via STAT3-dependent fatty acid oxidation. Consequently, the disruption of KRASG12D release and uptake can abolish the macrophage-mediated stimulation of pancreatic adenocarcinomas in mouse models. Importantly, the level of KRASG12D expression in macrophages correlates with poor survival in pancreatic cancer patients. These findings not only identify extracellular KRASG12D as a key mediator of cancer cell-macrophage communication, but also provide a novel KRAS-targeted anticancer strategy. Abbreviations: DAMP, damage-associated molecular pattern; PBMCMs, peripheral blood mononuclear cell-derived macrophages; PDAC, pancreatic ductal adenocarcinoma; s.c., subcutaneously; TAMs, tumor-associated macrophages; TME, tumor microenvironment.


Assuntos
Autofagia/fisiologia , Ferroptose/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Macrófagos Associados a Tumor/metabolismo , Adulto , Idoso , Carcinoma Ductal Pancreático/patologia , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Microambiente Tumoral/fisiologia
17.
Biochem Biophys Res Commun ; 523(4): 966-971, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31964528

RESUMO

Ferroptosis is a multi-step regulated cell death that is characterized by excessive iron accumulation and lipid peroxidation. Cancer cells can acquire resistance to ferroptosis by the upregulation of anti-ferroptotic proteins or by the downregulation of pro-ferroptotic proteins. Apoptosis-inducing factor mitochondria-associated 2 (AIFM2, also known as FSP1 or PRG3) has been recently demonstrated as an endogenous ferroptosis suppressor, but its mechanism remains obscure. Here, we show that AIFM2 blocks erastin-, sorafenib-, and RSL3-induced ferroptotic cancer cell death through a mechanism independent of ubiquinol, the reduced and active antioxidant form of coenzyme Q10. In contrast, AIFM2-dependent endosomal sorting complexes required for transport (ESCRT)-III recruitment in the plasma membrane is responsible for ferroptosis resistance through the activation of a membrane repair mechanism that regulates membrane budding and fission. Importantly, the genetic inhibition of the AIFM2-dependent ESCRT-III pathway increases the anticancer activity of sorafenib in a xenograft tumor mouse model. These findings shed new light on the mechanism involved in ferroptosis resistance during tumor therapy.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Ferroptose , Proteínas Mitocondriais/metabolismo , Ubiquinona/análogos & derivados , Animais , Antioxidantes/metabolismo , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Humanos , Camundongos Nus , Ubiquinona/metabolismo
18.
J Cancer ; 11(3): 583-591, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31942181

RESUMO

In recent years, the incidence of diabetes mellitus and cancer has increased sharply; indeed, these have become the two most important diseases threatening health and survival. Head and neck (HN) tumors are the sixth most common malignancies in humans. Numerous studies have shown that there are many common risk factors for diabetes mellitus and HN squamous cell carcinoma, including advanced age, poor diet and lifestyle, and environmental factors. However, the mechanism linking the two diseases has not been identified. A number of studies have shown that diabetes affects the development, metastasis, and prognosis of HN cancer, potentially through the associated hyperglycemia, hyperinsulinemia and insulin resistance, or chronic inflammation. More recent studies show that metformin, the first-line drug for the treatment of type 2 diabetes, can significantly reduce the risk of HN tumor development and reduce mortality in diabetic patients. Here, we review recent progress in the study of the relationship between diabetes mellitus and HN carcinogenesis, and its potential mechanisms, in order to provide a scientific basis for the early diagnosis and effective treatment of these diseases.

19.
Biochem Biophys Res Commun ; 522(2): 415-421, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31761326

RESUMO

Ferroptosis is a form of regulated cell death that is triggered by iron accumulation and lipid peroxidation. Although plasma membrane injuries represent an important event in cell death, the impact of membrane repair mechanisms on ferroptosis remains unidentified. Here, we provide the first evidence that membrane repair dependent on endosomal sorting complexes required for transport (ESCRT)-III negatively regulates ferroptotic cancer cell death. The accumulation of ESCRT-III subunits (e.g., CHMP5 and CHMP6) in the plasma membrane are increased by classical ferroptosis activators (e.g., erastin and RSL3), which relies on endoplasmic reticulum stress and calcium influx. Importantly, the knockdown of CHMP5 or CHMP6 by RNAi sensitizes human cancer cells (e.g., PANC1 and HepG2) to lipid peroxidation-mediated ferroptosis in vitro and in vivo. These findings suggest that ESCRT-III confers resistance to ferroptotic cell death, allowing cell survival under stress conditions.


Assuntos
Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ferroptose , Animais , Cálcio/metabolismo , Linhagem Celular Tumoral , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Humanos , Camundongos Nus
20.
J Immunother Cancer ; 7(1): 6, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30626434

RESUMO

Cancer vaccines and oncolytic immunotherapy are promising treatment strategies with potential to provide greater clinical benefit to patients with advanced-stage cancer. In particular, recombinant vaccinia viruses (VV) hold great promise as interventional agents. In this article, we first summarize the current understanding of virus biology and viral genes involved in host-virus interactions to further improve the utility of these agents in therapeutic applications. We then discuss recent findings from basic and clinical studies using VV as cancer vaccines and oncolytic immunotherapies. Despite encouraging results gleaned from translational studies in animal models, clinical trials implementing VV vectors alone as cancer vaccines have yielded largely disappointing results. However, the combination of VV vaccines with alternate forms of standard therapies has resulted in superior clinical efficacy. For instance, combination regimens using TG4010 (MVA-MUC1-IL2) with first-line chemotherapy in advanced-stage non-small cell lung cancer or combining PANVAC with docetaxel in the setting of metastatic breast cancer have clearly provided enhanced clinical benefits to patients. Another novel cancer vaccine approach is to stimulate anti-tumor immunity via STING activation in Batf3-dependent dendritic cells (DC) through the use of replication-attenuated VV vectors. Oncolytic VVs have now been engineered for improved safety and superior therapeutic efficacy by arming them with immune-stimulatory genes or pro-apoptotic molecules to facilitate tumor immunogenic cell death, leading to enhanced DC-mediated cross-priming of T cells recognizing tumor antigens, including neoantigens. Encouraging translational and early phase clinical results with Pexa-Vec have matured into an ongoing global phase III trial for patients with hepatocellular carcinoma. Combinatorial approaches, most notably those using immune checkpoint blockade, have produced exciting pre-clinical results and warrant the development of innovative clinical studies. Finally, we discuss major hurdles that remain in the field and offer some perspectives regarding the development of next generation VV vectors for use as cancer therapeutics.


Assuntos
Vetores Genéticos/genética , Imunoterapia , Neoplasias/terapia , Terapia Viral Oncolítica , Vírus Oncolíticos/genética , Vírus Vaccinia/genética , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Estudos Clínicos como Assunto , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Engenharia Genética , Terapia Genética , Vetores Genéticos/administração & dosagem , Interações Hospedeiro-Patógeno/imunologia , Humanos , Glicoproteínas de Membrana/administração & dosagem , Glicoproteínas de Membrana/imunologia , Neoplasias/genética , Neoplasias/imunologia , Vírus Oncolíticos/fisiologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Vírus Vaccinia/fisiologia
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