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1.
Immunity ; 55(2): 237-253.e8, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35081371

RESUMO

The Th17 cell-lineage-defining cytokine IL-17A contributes to host defense and inflammatory disease by coordinating multicellular immune responses. The IL-17 receptor (IL-17RA) is expressed by diverse intestinal cell types, and therapies targeting IL-17A induce adverse intestinal events, suggesting additional tissue-specific functions. Here, we used multiple conditional deletion models to identify a role for IL-17A in secretory epithelial cell differentiation in the gut. Paneth, tuft, goblet, and enteroendocrine cell numbers were dependent on IL-17A-mediated induction of the transcription factor ATOH1 in Lgr5+ intestinal epithelial stem cells. Although dispensable at steady state, IL-17RA signaling in ATOH1+ cells was required to regenerate secretory cells following injury. Finally, IL-17A stimulation of human-derived intestinal organoids that were locked into a cystic immature state induced ATOH1 expression and rescued secretory cell differentiation. Our data suggest that the cross talk between immune cells and stem cells regulates secretory cell lineage commitment and the integrity of the mucosa.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Mucosa Intestinal/citologia , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Interleucina-17/metabolismo , Células-Tronco/metabolismo , Animais , Comunicação Celular , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Humanos , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Intestinos/patologia , Camundongos , Camundongos Knockout , NF-kappa B/metabolismo , Receptores de Interleucina-17/deficiência , Fatores de Transcrição SOX9/metabolismo , Transdução de Sinais , Células-Tronco/citologia
2.
J Immunol ; 207(8): 1959-1963, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34544802

RESUMO

Previous studies indicate that IL-17A plays an important role in mediating the intestinal microbiota and systemic metabolic functions. However, it is not known where IL-17RA signaling occurs to mediate these effects. To investigate this question, we used intestinal epithelial-specific (Il17ra ΔIEC ) and liver-specific (Il17raΔLiver ) IL-17RA knockout mice as well as littermate control mice. Our results indicate that intestinal IL-17RA signaling helps mediate systemic metabolic functions upon exposure to prolonged high-fat diet. Il17ra ΔIEC mice display impaired glucose metabolism, altered hormone and adipokine levels, increased visceral adiposity, and greater hepatic lipid deposition when compared with their littermate controls. We show that IL-17RA-driven changes in microbiota composition are responsible for regulating systemic glucose metabolism. Altogether, our data elucidate the importance of intestinal IL-17RA signaling in regulating high-fat diet-mediated systemic glucose and lipid metabolism.


Assuntos
Interleucina-17/metabolismo , Mucosa Intestinal/fisiologia , Fígado/fisiologia , Doenças Metabólicas/imunologia , Microbiota/imunologia , Receptores de Interleucina-17/metabolismo , Adipocinas/metabolismo , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Glucose/metabolismo , Hormônios/metabolismo , Humanos , Metabolismo dos Lipídeos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
3.
Exp Cell Res ; 388(2): 111860, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972222

RESUMO

There is growing evidence to support a role for the ceramide-metabolizing enzyme, glucosylceramide synthase (GCS), in resistance to a variety of chemotherapeutic agents. Whether GCS contributes to oxaliplatin resistance in colorectal cancer (CRC) has not yet been determined. We have addressed this potentially important clinical issue by examining GCS function in two panels of oxaliplatin-resistant, isogenic CRC cell lines. Compared to parental cell lines, oxaliplatin-resistant cells have increased expression of GCS protein associated with increased levels of the pro-survival ceramide metabolite, glucosylceramide (GlcCer). Inhibition of GCS expression by RNAi-mediated gene knockdown resulted in a reduction in cellular GlcCer levels, with restored sensitivity to oxaliplatin. Furthermore, oxaliplatin-resistant CRC cells displayed lower ceramide levels both basally and after treatment with oxaliplatin, compared to parental cells. GlcCer, formed by GCS-mediated ceramide glycosylation, is the precursor to a complex array of glycosphingolipids. Differences in cellular levels and species of gangliosides, a family of glycosphingolipids, were also seen between parental and oxaliplatin-resistant CRC cells. Increased Akt activation was also observed in oxaliplatin-resistant CRC cell lines, together with increased expression of the anti-apoptotic protein survivin. Finally, this study shows that GCS protein levels are greatly increased in human CRC specimens, compared to matched, normal colonic mucosa, and that high levels of UGCG gene expression are significantly associated with decreased disease-free survival in colorectal cancer patients. These findings uncover an important cellular role for GCS in oxaliplatin chemosensitivity and may provide a novel cellular target for augmenting chemotherapeutic drug effectiveness in CRC.


Assuntos
Ceramidas/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Glucosiltransferases/metabolismo , Oxaliplatina/farmacologia , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Glicosilação , Humanos , Células Tumorais Cultivadas
4.
J Immunother ; 47(8): 303-312, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38847148

RESUMO

Triple-negative breast cancer (TNBC) lacks sensitivity to endocrine and targeted therapies, exhibiting high recurrence and poor prognosis postchemotherapy. Tumor-associated macrophages (TAMs) play a crucial role in cancer progression. Vitexin, a compound with diverse pharmacological effects including anti-cancer activity, remains unexplored in its impact on TAMs during TNBC development. This study aimed to investigate vitexin's effect on TNBC, its regulation of macrophage polarization (M1 vs. M2), and the underlying EGFR/PI3K/AKT/mTOR pathway. Our results demonstrated that vitexin suppressed the proliferation and invasion of TNBC cells (MDA-MB-231 and BT549) while inducing macrophage mediators that further inhibited cancer cell migration. Vitexin also promoted M1 polarization and suppressed M2 polarization, affecting EGFR phosphorylation and downstream signaling. In vivo, vitexin inhibited tumor growth, favoring M1 polarization and suppressing M2 polarization, with synergistic effects when combined with doxorubicin (Dox). These findings offer novel insights into vitexin's potential in TNBC treatment.


Assuntos
Apigenina , Proliferação de Células , Receptores ErbB , Transdução de Sinais , Neoplasias de Mama Triplo Negativas , Apigenina/farmacologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Animais , Receptores ErbB/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Linhagem Celular Tumoral , Feminino , Camundongos , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Metástase Neoplásica , Progressão da Doença , Serina-Treonina Quinases TOR/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Macrófagos Associados a Tumor/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Doxorrubicina/farmacologia
5.
Nat Commun ; 15(1): 1597, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383607

RESUMO

IL-22 is critical for ameliorating obesity-induced metabolic disorders. However, it is unknown where IL-22 acts to mediate these outcomes. Here we examine the importance of tissue-specific IL-22RA1 signaling in mediating long-term high fat diet (HFD) driven metabolic disorders. To do so, we generated intestinal epithelium-, liver-, and white adipose tissue (WAT)-specific Il22ra1 knockout and littermate control mice. Intestinal epithelium- and liver-specific IL-22RA1 signaling upregulated systemic glucose metabolism. Intestinal IL-22RA1 signaling also mediated liver and WAT metabolism in a microbiota-dependent manner. We identified an association between Oscillibacter and elevated WAT inflammation, likely induced by Mmp12 expressing macrophages. Mechanistically, transcription of intestinal lipid metabolism genes is regulated by IL-22 and potentially IL-22-induced IL-18. Lastly, we show that Paneth cell-specific IL-22RA1 signaling, in part, mediates systemic glucose metabolism after HFD. Overall, these results elucidate a key role of intestinal epithelium-specific IL-22RA1 signaling in regulating intestinal metabolism and alleviating systemic obesity-associated disorders.


Assuntos
Fígado , Doenças Metabólicas , Animais , Camundongos , Fígado/metabolismo , Inflamação/metabolismo , Obesidade/metabolismo , Metabolismo dos Lipídeos , Glucose/metabolismo , Doenças Metabólicas/metabolismo , Lipídeos , Dieta Hiperlipídica/efeitos adversos , Camundongos Endogâmicos C57BL
6.
Clin Transl Radiat Oncol ; 39: 100566, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36582422

RESUMO

Background and purpose: Incidental thyroid gland irradiation frequently occurs in breast cancer patients who receive regional nodal irradiation (RNI) to the supraclavicular (SCV) region. Recent studies suggest hypothyroidism (HT) is a complication of radiation therapy (RT) that includes SCV fields. We retrospectively analyzed patients who received RNI to evaluate thyroid gland evolution following RT as well as its association with the development of HT. Materials and methods: 61 breast cancer patients received SCV-directed RT between 2007 and 2019 and met inclusion criteria. Thyroid glands were retrospectively contoured on CT simulation and follow-up images. Individual dose-volume histograms were analyzed to determine thyroid volume within and outside specific isodose lines. Relative thyroid volume changes based on different radiation doses were estimated by fusing post-RT scans with CT simulation. Logistic regression was performed to assess thyroid volume changes as a factor in the development of HT. Results: Median pre-treatment thyroid volume was 11.8 cc (range: 6.3-74.1 cc) with a median of 42.2 % within the 20 Gy and 23.2 % within the 40 Gy isodose lines. A significant decrease in thyroid volume was noted by 1-year post-treatment (p < 0.0001) and thereafter. By 4 years post-treatment, average thyroid volume was decreased by 29.7 % (range: 2.3-64.4 %). Thyroid volume receiving 40 Gy or higher demonstrated a greater decrease compared to those receiving lower irradiation dosage. HT occurred in 17 patients (27.9 %). Patients who developed HT displayed a larger decrease in the thyroid volume receiving between 20 and 40 Gy at 12 months (p = 0.033). Conclusion: Our study demonstrates for the first time that a reduction in thyroid volume may be seen as early as 6 months after SCV-directed RT for breast cancer, which correlates with development of clinical and subclinical HT. Furthermore, a dose-dependent correlation exists between thyroid subvolume reduction and SCV-directed RT in breast cancer patients. As feasible, efforts should be made to reduce the dose to the thyroid in patients who undergo RNI for breast cancer.

7.
Molecules ; 17(9): 11216-28, 2012 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-22996345

RESUMO

Salvianolic acid A (SalA) is one of the main efficacious, water-soluble constituents of Salvia miltiorrhiza Bunge. This study investigated the protective effects of SalA on peripheral nerve in diabetic rats. Administration of SalA (0.3, 1 and 3 mg/kg, ig) was started from the 5th week after strepotozotocin (STZ60 mg/kg) intraperitoneal injection and continued for 8 weeks. Paw withdrawal mechanical threshold (PWMT) and motor nerve conduction velocity (MNCV) were used to assess peripheral nerve function. The western blot methods were employed to test the expression levels of serine-threonine liver kinase B1 (LKB1), AMP-activated protein kinase (AMPK), peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1α), silent information regulator protein3 (sirtuin 3/Sirt3) and neuronal nitric oxide synthase (nNOS) in sciatic nerve. Results showed that SalA administration could increase PWMT and MNCV in diabetic rats; reduce the deterioration of sciatic nerve pathology; increase AMPK phosphorylation level, up-regulate PGC-1α, Sirt3 and nNOS expression, but had no influence on LKB1. These results suggest that SalA has protective effects against diabetic neuropathy. The beneficial effects of SalA on peripheral nerve function in diabetic rats might be attributed to improvements in glucose metabolism through regulation of the AMPK-PGC1α-Sirt3 axis.


Assuntos
Ácidos Cafeicos/farmacologia , Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/prevenção & controle , Lactatos/farmacologia , Nervos Periféricos/efeitos dos fármacos , Proteínas Quinases/metabolismo , Proteínas de Ligação a RNA/metabolismo , Sirtuína 3/metabolismo , Fatores de Transcrição/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Ácidos Cafeicos/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Produtos Finais de Glicação Avançada/sangue , Lactatos/química , Malondialdeído/sangue , Óxido Nítrico Sintase Tipo I/biossíntese , Nervos Periféricos/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Proteínas Serina-Treonina Quinases/biossíntese , Ratos , Salvia miltiorrhiza , Nervo Isquiático/efeitos dos fármacos , Estreptozocina , Superóxido Dismutase/sangue
8.
Radiother Oncol ; 154: 87-92, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32926911

RESUMO

BACKGROUND AND PURPOSE: Hypothyroidism (HT) is a well-known complication of radiation (RT) that includes supraclavicular (SCV) fields. We analyzed breast cancer patients who received SCV-directed RT to evaluate predictors of HT and developed the first normal tissue complication probability (NTCP) model for HT specific to breast cancer patients. MATERIALS AND METHODS: 192 breast cancer patients received SCV-directed RT between 2007 and 2019 and met inclusion criteria. Individual dose-volume histograms were analyzed to determine thyroid volume within and outside specific isodose lines as well as minimum, mean, and maximum doses. Multivariable logistic regression was performed to assess potential clinical and treatment factors for the development of hypothyroidism. An NTCP model was created, and model validation was performed. RESULTS: Thirty-seven patients (19.3%) developed HT following SCV-directed RT at a median 25 months (range: 2-83 months). Multivariable analysis revealed longer length of follow-up (p = 0.015) and larger thyroid volume receiving less than 20 Gy (CV20Gy[cc]; p = 0.045) were significant prognostic factors (p = 0.039). IMRT was not associated with an increased risk of hypothyroidism (p = 0.28) despite lower CV20Gy[cc] (p = 0.0002). On NTCP modeling, CV20Gy[cc] ≥ 8.5 cc was associated with a risk of HT < 15%. For smaller thyroids, mean dose and thyroid volume were found to be predictive of HT risk. Model validation demonstrated comparable performances between our model and other published models (AUC 0.69-0.72). CONCLUSION: NTCP modeling within our patient cohort suggested that greater than 8.5 cc thyroid volume receiving less than 20 Gy may be a recommended dosimetric guideline to minimize HT risk in breast cancer patients receiving SCV-directed RT.


Assuntos
Neoplasias da Mama , Hipotireoidismo , Neoplasias da Mama/radioterapia , Humanos , Hipotireoidismo/etiologia , Probabilidade , Radiometria , Dosagem Radioterapêutica
9.
Sci Rep ; 9(1): 4954, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894570

RESUMO

The platinum-based chemotherapeutic agent, oxaliplatin, is used to treat advanced colorectal cancer (CRC). Unfortunately, nearly all patients acquire resistance to oxaliplatin after long-term use, limiting its therapeutic efficacy. Since COX-2 and PGE2 signaling can impact colon cancer cell proliferation and survival, we examined how this pathway was affected in an oxaliplatin resistant colon cancer cell line. PGE2 levels were significantly elevated in oxaliplatin-resistant HT29 cells (OXR) compared to naïve parental HT29 cells (PAR). This increase was associated with elevated COX-2 (17.9-fold; P = 0.008) and reduced 15-hydroxyprostaglandin dehydrogenase (2.9-fold; P < 0.0001) expression. RNAi knockdown of microsomal prostaglandin E synthase-1, the rate-limiting enzyme in PGE2 synthesis, sensitized OXR cells to oxaliplatin. Downstream effects of PGE2 in OXR cells were also examined. Selective inhibition of the EP4 PGE2 receptor by the small molecule inhibitor, L-161,982 enhanced oxaliplatin-induced apoptosis in OXR cells. L-161,982 also reduced expression of the colonic stem cell markers, CD133 and CD44, and inhibited tumor sphere formation. The accumulation of intracellular reactive oxygen species (ROS), a key component of oxaliplatin cytotoxicity, was significantly increased by EP4 inhibition (2.4 -fold; P < 0.0001). Overall, our findings uncover an important role for the COX-2/PGE2/EP4 signaling axis in oxaliplatin resistance via regulation of oxidative stress.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias do Colo/tratamento farmacológico , Oxaliplatina/farmacologia , Receptores de Prostaglandina E Subtipo EP4/antagonistas & inibidores , Tiofenos/farmacologia , Triazóis/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/patologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Técnicas de Silenciamento de Genes , Células HT29 , Humanos , Oxaliplatina/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tiofenos/uso terapêutico , Triazóis/uso terapêutico
11.
Cancer Immunol Res ; 3(5): 536-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25633711

RESUMO

The presence of tumor-infiltrating CD8(+) T cells is associated with tumor regression and better prognosis. Cytomegalovirus (CMV) infection elicits a robust and long-lasting CD8(+) T-cell response, which makes CMV a potentially promising vaccine vector against cancer. In the current study, we used recombinant murine CMV (MCMV) strains as prophylactic and therapeutic vaccines in an aggressive B16 lung metastatic melanoma model. Immunization with MCMV-expressing ovalbumin (OVA) induced a potent OVA-specific CD8(+) T-cell response and was effective in protecting mice from OVA-expressing B16 melanoma in an antigen-dependent manner. We engineered MCMV to express a modified B16 melanoma antigen gp100 (MCMV-gp100KGP). Immunization with MCMV-gp100KGP was highly effective in overcoming immune tolerance to self-antigen and induced a strong, long-lasting gp100-specific CD8(+) T-cell response even in the presence of preexisting anti-CMV immunity. Furthermore, both prophylactic and therapeutic vaccinations of mice with MCMV-gp100KGP effectively protected mice from highly aggressive lung B16-F10 melanoma, and the protection was mediated by gp100-specific CD8(+) T cells. We showed that MCMV is a superior vaccine vector compared with a commonly used vesicular stomatitis virus vector. Collectively, our studies demonstrate that CMV is a promising vaccine vector to prevent and treat tumors.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/uso terapêutico , Citomegalovirus/imunologia , Neoplasias Pulmonares/prevenção & controle , Melanoma Experimental/prevenção & controle , Antígeno gp100 de Melanoma/imunologia , Animais , Feminino , Neoplasias Pulmonares/secundário , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Ovalbumina/imunologia
12.
PLoS One ; 8(11): e75493, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223114

RESUMO

Zinc Finger Nucleases (ZFNs), famous for their ability to precisely and efficiently modify specific genomic loci, have been employed in numerous transgenic model organism and cell constructions. Here we employ the ZFNs technology, with homologous recombination (HR), to construct sequence-specific Amyloid Precursor Protein (APP) knock-in cells. With the use of ZFNs, we established APP knock in cell lines with gene-modification efficiencies of about 7%. We electroporated DNA fragment containing the promoter and the protein coding regions of the zinc finger nucleases into cells, instead of the plasmids, to avoid problems associated with off target homologous recombination, and adopted a pair of mutated FokI cleavage domains to reduce the toxic effects of the ZFNs on cell growth. Since over-expression of APP, or a subdomain of it, might lead to an immediately lethal effect, we used the Cre-LoxP System to regulate APP expression. Our genetically transformed cell lines, w5c1 and s12c8, showed detectable APP and Amyloid ß (Aß) production. The Swedish double mutation in the APP coding sequence enhanced APP and Aß abundance. What is more, the activity of the three key secretases in Aß formation could be modulated, indicating that these transgenic cells have potential for drug screening to modify amyloid metabolism in cells. Our transformed cells could readily be propagated in culture and should provide an excellent experimental medium for elucidating aspects of the molecular pathogenesis of Alzheimer's disease, especially those concerning the amyloidogenic pathways involving mutations in the APP coding sequence. The cellular models may also serve as a tool for deriving potentially useful therapeutic agents.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/genética , Desoxirribonucleases/genética , Fragmentos de Peptídeos/genética , Peptídeos beta-Amiloides/biossíntese , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose , Células 3T3 BALB , Sequência de Bases , Inibidores da Colinesterase/farmacologia , Clivagem do DNA , Desoxirribonucleases/biossíntese , Donepezila , Avaliação Pré-Clínica de Medicamentos , Galantamina/farmacologia , Expressão Gênica , Engenharia Genética , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Recombinação Homóloga , Humanos , Ibuprofeno/farmacologia , Indanos/farmacologia , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/biossíntese , Piperidinas/farmacologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Dedos de Zinco
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