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BACKGROUND: Pharmacokinetic non-inferiority of subcutaneous (SC) to intravenous (IV) CT-P13 maintenance therapy was demonstrated in a randomized trial (NCT02883452). This post hoc analysis evaluated longitudinal clinical outcomes with the two infliximab treatment strategies. METHODS: Patients with Crohn's disease or ulcerative colitis received CTP13 IV loading doses (5â¯mg/kg; Week [W] 0 and W2) before randomization (1:1) to receive CT-P13 SC (body weight-based dosing every 2 weeks [Q2W]; W6-54; 'SC maintenance group') or CTP13 IV (5â¯mg/kg Q8W; W6-22) then CT-P13 SC (Q2W; W30-54; 'IV-to-SC switch group'). Paired W30/W54 patient-level data were analyzed. RESULTS: Fifty-three (IV-to-SC switch) and fifty-nine (SC maintenance) patients were analyzed. Median trough serum CT-P13 concentrations were significantly higher at W54 versus W30 in the IV-to-SC switch group (20.4 versus 2.3⯵g/mL; p < 0.00001), while remaining consistent in the SC maintenance group. Statistically significant improvements in pharmacokinetics, efficacy, fecal calprotectin levels, and quality of life were seen following switch to SC administration at W30 in the IV-to-SC switch group; safety findings were similar pre- and post-switch. CONCLUSION: Formulation switching from IV to SC infliximab maintenance therapy was well tolerated and may provide additional clinical improvements. Findings require confirmation in larger prospective studies.
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Fármacos Gastrointestinais , Infliximab , Humanos , Infliximab/administração & dosagem , Infliximab/farmacocinética , Infliximab/uso terapêutico , Feminino , Masculino , Injeções Subcutâneas , Adulto , Estudos Longitudinais , Pessoa de Meia-Idade , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/farmacocinética , Doença de Crohn/tratamento farmacológico , Administração Intravenosa , Colite Ulcerativa/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacocinética , Quimioterapia de Manutenção , Resultado do Tratamento , Substituição de Medicamentos , Complexo Antígeno L1 Leucocitário/análiseRESUMO
The pH-selective interaction between the immunoglobulin G (IgG) fragment crystallizable region (Fc region) and the neonatal Fc receptor (FcRn) is critical for prolonging the circulating half-lives of IgG molecules through intracellular trafficking and recycling. By using directed evolution, we successfully identified Fc mutations that improve the pH-dependent binding of human FcRn and prolong the serum persistence of a model IgG antibody and an Fc-fusion protein. Strikingly, trastuzumab-PFc29 and aflibercept-PFc29, a model therapeutic IgG antibody and an Fc-fusion protein, respectively, when combined with our engineered Fc (Q311R/M428L), both exhibited significantly higher serum half-lives in human FcRn transgenic mice than their counterparts with wild-type Fc. Moreover, in a cynomolgus monkey model, trastuzumab-PFc29 displayed a superior pharmacokinetic profile to that of both trastuzumab-YTE and trastuzumab-LS, which contain the well-validated serum half-life extension Fcs YTE (M252Y/S254T/T256E) and LS (M428L/N434S), respectively. Furthermore, the introduction of two identified mutations of PFc29 (Q311R/M428L) into the model antibodies enhanced both complement-dependent cytotoxicity and antibody-dependent cell-mediated cytotoxicity activity, which are triggered by the association between IgG Fc and Fc binding ligands and are critical for clearing cancer cells. In addition, the effector functions could be turned off by combining the two mutations of PFc29 with effector function-silencing mutations, but the antibodies maintained their excellent pH-dependent human FcRn binding profile. We expect our Fc variants to be an excellent tool for enhancing the pharmacokinetic profiles and potencies of various therapeutic antibodies and Fc-fusion proteins.
Assuntos
Antígenos de Histocompatibilidade Classe I , Imunoglobulina G , Camundongos , Animais , Humanos , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Macaca fascicularis/metabolismo , Meia-Vida , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Camundongos Transgênicos , Mutação , Trastuzumab/uso terapêutico , Trastuzumab/genéticaRESUMO
Following the publication of the above article, an interested reader drew to the authors' attention that they had mentioned that activated PKCδ phosphorylates IKKß in order that IKKß is relocated to the plasma membrane, resulting in the induction of mast cell degranulation; however, four references the authors had included did not seem to support this statement. The authors have re-examined their paper, and realized that the four references the reader mentioned were indeed cited incorrectly, and wish to rectify this error through revising the third paragraph in the Discussion section, the References section, and an associated figure (Fig. 6C) in order to avoid any further misunderstandings on the part of the readership. First, the authors wish to revise the wording of the third and fourth paragraphs of the Discussion, as featured on pp. 1101-1102, to the following (changed text is indicated in bold): 'We showed that CRT exerts anti-AD effect through inhibition of the mast cell degranulation in mast cells. Upon IgE/antigen stimulation, the immunoreceptor tyrosine-based activation motif (ITAM) region of FcεRI receptor which is on the mast cell surface is phosphorylated and the initial signalling protein kinases Lyn and Syk are recruited to the ITAM (28,29). Then, the activated Lyn and Syk leads to phosphorylation of the transmembrane adaptor linker for activation of T cells (LAT). Phosphorylated LAT which is a scaffold for multimolecular signalling complexes and activates PLCγ through phosphorylation. The activated PLCγ hydrolyses phosphatidylinositol biphosphate (PIP2) to generate second signalling molecules IP3 and DAG, which activate PKCs including PKCδ to induce the mast cell degranulation (30,31). On the other hand, cross-linking of FcεRI also activates IKKß, which moves to the lipid raft fractions and phosphorylates synaptosomal-associated protein 23 (SNAP-23) leading to degranulation (7). Since PKCδ phosphorylates IKKα, but not IKKß (32), it is not likely that two signalling pathways are directly connected. In this study, novel function of CRT on phosphorylations of Lyn/Syk kinases in mast cells is elucidated for the first time. Furthermore, it is likely that this inhibitory effect of CRT on Lyn/Syk kinases negatively affected activities of their downstream signalling molecules including PLCγ, PKCδ, and IKKß, which leads to decrease in mast cell degranulation by CRT treatment. Besides the inhibitory effect of CRT on mast cell degranulation, here we provide additional evidence that CRT exerts anti-AD effects through inactivation of MAPK and NFκB. It has been reported that CRT regulates the activities of MAPK and NFκB in various cell types. In rhabdomyosarcoma, hepatoma, and breast carcinoma, CRT activates MAPK p38/JNK and suppresses ERK1/2, followed by caspase-independent apoptosis (10,33,34). In chronic myeloid leukaemia cells, CRT enhances TNFα-induced apoptosis through the activation of MAPK p38 (35). In smooth muscle cells, CRT exerts anti-migration/invasion effect as it inhibits TNFα/NFκB signalling pathway (36).' Secondly, the authors wish to make the following changes to the Reference list: New references 30-32 have been inserted to the list, as follows: 30. Ozawa K, Szallasi Z, Kazanietz MG, Blumberg PM, Mischak H, Mushinski JF and Beaven MA: Ca2+-dependent and Ca2+-independent isozymes of protein kinase C mediate exocytosis in antigen-stimulated rat basophilic RBL-2H3 cell. J Biol Chem 268: 1749-1756, 1993. 31. Cho SH, Woo CH, Yoon SB and Kim JH: Protein kinase Cδ functions downstream of Ca2+ mobilization in FcεRI signaling to degranulation in mast cells. J Allergy Clin Immunol 114: 1085-1092, 2004. 32. Yamaguchi T, Miki Y and Yoshida K: Protein kinase Cδ activates IκB-kinase α to induce the p53 tumor suppressor in response to oxidative stress. Cell Signal 19: 2088-2097, 2007. The addition of these new references means that the former references 30-33 have been accordingly renumbered to references 33-36. Finally, the authors have revised Fig. 6C, as it appeared on p. 1102, in order to assist the understanding of the readers, and the corrected version of Fig. 6 appears on the next page. All these corrections have been approved by all the authors, with the exception of the first author, Sumiyasuren Buyanravjikh, who is no longer uncontactable. The authors regret that these errors were included in the paper, even though they did not substantially alter any of the major conclusions reported in the study, are grateful to the Editor for allowing them this opportunity to publish a Corrigendum, and apologize to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 18: 10951193, 2018; DOI: 10.3892/mmr.2018.9042].
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IK depletion leads to an aberrant mitotic entry because of chromosomal misalignment through the enhancement of Aurora B activity at the interphase. Here, we demonstrate that IK, a spliceosomal component, plays a crucial role in the proper splicing of the ATM pre-mRNA among other genes related with the DNA Damage Response (DDR). Intron 1 in the ATM pre-mRNA, having lengths <200 bp, was not spliced in the IK-depleted cells and led to a deficiency of the ATM protein. Subsequently, the IK depletion-induced ATM protein deficiency impaired the ability to repair the damaged DNA. Because the absence of SMU1 results in IK degradation, the mechanism underlying IK degradation was exploited. IK was ubiquitinated in the absence of SMU1 and then subjected to proteolysis through the 26S proteasome. To prevent the proteolytic degradation of IK, a deubiquitinating enzyme, USP47, directly interacted with IK and stabilized it through deubiquitination. Collectively, our results suggest that IK is required for proper splicing of the ATM pre-mRNA and USP47 contributes toward the stabilization of IK.
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RATIONALE: Circulating CTRP1 (C1q/TNF-α [tumor necrosis factor-α]-related protein 1) levels are increased in hypertensive patients compared with those in healthy subjects. Nonetheless, little is known about the molecular and physiological function of CTRP1 in blood pressure (BP) regulation. OBJECTIVE: To investigate the physiological/pathophysiological role of CTRP1 in BP regulation. METHODS AND RESULTS: CTRP1 production was increased to maintain normotension under dehydration conditions, and this function was impaired in inducible CTRP1 KO (knockout) mice (CTRP1 ΔCAG). The increase in CTRP1 under dehydration conditions was mediated by glucocorticoids, and the antagonist mifepristone prevented the increase in CTRP1 and attenuated BP recovery. Treatment with a synthetic glucocorticoid increased the transcription, translation, and secretion of CTRP1 from skeletal muscle cells. Functionally, CTRP1 increases BP through the stimulation of the AT1R (Ang II [angiotensin II] receptor 1)-Rho (Ras homolog gene family)/ROCK (Rho kinase)-signaling pathway to induce vasoconstriction. CTRP1 promoted AT1R plasma membrane trafficking through phosphorylation of AKT and AKT substrate of 160 kDa (AS160). In addition, the administration of an AT1R blocker, losartan, recovered the hypertensive phenotype of CTRP1 TG (transgenic) mice. CONCLUSIONS: For the first time, we provide evidence that CTRP1 contributes to the regulation of BP homeostasis by preventing dehydration-induced hypotension.
Assuntos
Adipocinas/metabolismo , Pressão Sanguínea , Desidratação/metabolismo , Hipotensão/metabolismo , Adipocinas/genética , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Linhagem Celular , Células Cultivadas , Desidratação/complicações , Desidratação/fisiopatologia , Feminino , Glucocorticoides/metabolismo , Humanos , Hipotensão/tratamento farmacológico , Hipotensão/etiologia , Hipotensão/fisiopatologia , Losartan/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Vasoconstrição , Quinases Associadas a rho/metabolismoRESUMO
[This corrects the article DOI: 10.3892/ol.2017.6957.].
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Atopic dermatitis (AD) is a type of chronic skin inflammation and one of the most common relapsing allergic diseases, which presents with a severe rash and itchy skin lesions. The pathogenesis of AD is primarily associated with hyperactivated mast cells, which makes them an effective treatment target. After crosslinking the antigen/immunoglobulin (Ig) E complex binds to its high affinity receptor FcεRl on the surface of mast cells. The cells subsequently secrete excessive proinflammatory mediators, including histamine and cytokines, which lead to pruritus and immune cell infiltration in the skin lesions. The present study screened natural compounds that have an inhibitory effect on IgE/antigenmediated secretory activity. It was revealed that cryptotanshinone (CRT), a natural compound extracted from Salvia miltiorrhiza Bunge, had inhibitory effects on the IgE/antigen complex. The underlying mechanism by which CRT exerted an antiallergy/inflammatory function was investigated using rat basophilic leukaemia (RBL) cells for degranulation assays and a 1chloro2,4dinitrobenzene (DNCB)induced AD Balb/c mouse model for in vivo study. CRT effectively mitigated the secretion of proinflammatory cytokines, including tumor necrosis factorα and interleukin 1ß, as well as immune cell infiltration into skin lesions in a mouse model of ADlike skin disease induced by dinitrochlorobenzene. The inhibitory effect of CRT on IgEmediated mast cell degranulation was mediated by the inhibition of tyrosine kinasedependent degranulation signalling pathways involving spleen tyrosine kinase and Lyn. The present study revealed CRT as an inhibitor of mast cell degranulation. Therefore, CRT may be considered for development as a therapeutic drug to treat IgEmediated skin diseases.
Assuntos
Degranulação Celular/efeitos dos fármacos , Dermatite Atópica/metabolismo , Imunoglobulina E/metabolismo , Mastócitos/metabolismo , Fenantrenos/farmacologia , Quinase Syk/metabolismo , Animais , Linhagem Celular Tumoral , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Interleucina-1beta/metabolismo , Masculino , Mastócitos/patologia , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação/efeitos dos fármacos , Ratos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
In most mammalian cells, the primary cilium is a microtubule-enriched protrusion of the plasma membrane and acts as a key coordinator of signaling pathways during development and tissue homeostasis. The primary cilium is generated from the basal body, and cancerous inhibitor of protein phosphatase 2A (CIP2A), the overexpression of which stabilizes c-MYC to support the malignant growth of tumor cells, is localized in the centrosome. Here, we show that CIP2A overexpression induces primary cilia disassembly through the activation of Aurora A kinase, and CIP2A depletion increases ciliated cells and cilia length in retinal pigment epithelium (RPE1) cells. CIP2A depletion also shifts metabolism toward the glycolytic pathway by altering the expression of metabolic genes related to glycolysis. However, glycolytic activation in CIP2A-depleted cells does not depend on cilia assembly, even though enhanced cilia assembly alone activates glycolytic metabolism. Collectively, these data suggest that CIP2A promotes primary cilia disassembly and that CIP2A depletion induces metabolic reprogramming independent of primary cilia.
Assuntos
Autoantígenos/metabolismo , Cílios/patologia , Glicólise , Proteínas de Membrana/metabolismo , Proteínas Oncogênicas/metabolismo , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Autoantígenos/genética , Proliferação de Células , Células Epiteliais/citologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Neoplasias/genética , Proteínas Oncogênicas/genética , Epitélio Pigmentado da Retina/citologia , Transdução de SinaisRESUMO
Circulating tumor cells (CTCs) are essential for the establishment of distant metastasis. Numerous studies have characterized CTCs as metastatic precursors; however, the molecular nature of CTCs has not been completely revealed yet due to the low number of CTCs in the blood stream. As an alternative approach, we developed a long-term suspension cell culture model using human breast cancer cell lines to mimic CTCs. We found that more than 40 passaged suspension cells acquired the ability to enhance metastasis like cancer stem cells. To identify molecular changes acquired during the suspension cell culture, we analyzed metabolic and lipidomic profiles as well as transcriptome in MDA-MB-468 suspension cells. Glutamate and leucine levels increased in suspension cells, and cholesterol synthesis pathway was altered. The inhibition of glutamate metabolic pathway decreased the proliferation of suspension cells compared to that of adherent cells. In the lipidomic profile, PC species containing long chain and polyunsaturated fatty acids increased in suspension cells and these species could be authentic and specific biomarkers for highly metastatic cancers. As this CTC-mimicking suspension cell culture model may easily apply to various types of cancer, we suggest this model as a great tool to develop therapeutic targets and drugs to eradicate metastatic cancer cells.
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The epithelial-mesenchymal transition (EMT) is a hallmark of cancer metastasis, and the associated molecular signaling pathways are regarded as therapeutic targets for cancer treatment. Thus, suppressing EMT with a natural chemical compound may be of therapeutic benefit. Eupatolide is a natural chemical compound extracted from the medicinal plant Inula britannica, which is used in Eastern Asia to treat bronchitis, disorders of the digestive system and inflammation. Besides the anti-inflammatory function of eupatolide, the present study found that eupatolide suppressed the migration and invasion of breast cancer cells, which was associated with the downregulation of vimentin in MDA-MB-231 cells and the upregulation of E-cadherin in MCF-7 cells. Treatment with eupatolide also significantly inhibited the migration and invasion of breast cancer cells that had been stimulated with transforming growth factor-ß1 (TGF-ß1). Eupatolide also suppressed TGF-ß1-induced EMT via downregulation of mothers against decapentaplegic homolog 3 (SMAD3) phosphorylation and transcriptional repression of TGF-ß receptor 1 (ALK5). In addition to this canonical pathway, the non-canonical protein kinase B (AKT) and extracellular signal-regulated kinase (ERK) pathways were also inhibited by eupatolide treatment. In summary, the results suggest that eupatolide suppresses the migration and invasion of breast cancer cells by blocking the canonical ALK5-SMAD3 signaling pathway and the non-canonical ERK and AKT signaling pathways.
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Neuronatin (NNAT) is known to regulate ion channels during brain development and plays a role in maintaining the structure of the nervous system. A previous in silico analysis showed that Nnat was overexpressed in the adipose tissue of an obese rodent model relative to the wild type. Therefore, the aim of the present study was to investigate the function of Nnat in the adipose tissue. Because obesity is known to systemically induce low-grade inflammation, the Nnat expression level was examined in the adipose tissue obtained from C57BL/6 mice administered lipopolysaccharide (LPS). Unexpectedly, the Nnat expression level decreased in the white adipose tissue after LPS administration. To determine the role of NNAT in inflammation, 3T3-L1 cells overexpressing Nnat were treated with LPS. The level of the p65 subunit of nuclear factor-kappa B (NF-κB) and the activity of NF-κB luciferase decreased following LPS treatment. These results indicate that NNAT plays an anti-inflammatory role in the adipose tissue.
Assuntos
Tecido Adiposo Branco/imunologia , Inflamação , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Células 3T3-L1 , Tecido Adiposo Branco/citologia , Tecido Adiposo Branco/efeitos dos fármacos , Animais , Simulação por Computador , Expressão Gênica , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/efeitos dos fármacos , NF-kappa B/genética , Obesidade/imunologia , Transdução de SinaisRESUMO
The goal of this study was to investigate whether circulating C1q/TNF-α-related protein 1 (CTRP1) levels are associated with diabetes. In addition, relationships between CTRP1 and other diabetes-related cytokines were elucidated, including adiponectin and fibroblast growth factor 21 (FGF21). A total of 178 subjects (78 men and 100 women) aged 29-70 years (mean age, 46.1 years) were randomly selected. The sera from a normal glucose tolerance group (n = 68) and a prediabetes/type 2 diabetes group (n = 110) were collected; then, circulating levels of CTRP1, adiponectin, and FGF21 were determined via enzyme-linked immunosorbent assay in all sera. Subjects with either prediabetes or diabetes exhibited higher circulating CTRP1 levels than healthy subjects. Sera analysis revealed that CTRP1 was positively correlated with age, body mass index, fasting blood glucose, and circulating FGF21 levels. However, CTRP1 was negatively correlated with total cholesterol and total circulating adiponectin levels in univariate analysis. In addition, multivariate analysis found that CTRP1 was independently associated with age, fasting blood glucose, and circulating FGF21 levels. CTRP1 was correlated with homeostasis model assessment-ß (HOMA-ß), but no correlation was observed with HOMA-insulin resistance. In conclusion, circulating CTRP1 levels are increased in subjects with type 2 diabetes and are positively associated with circulating FGF21 levels.
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Mutation of PPP2R1A has been observed at high frequency in endometrial serous carcinomas but at low frequency in ovarian clear cell carcinoma. However, the biological role of mutation of PPP2R1A in ovarian and endometrial cancer progression remains unclear. In this study, we found that PPP2R1A expression is elevated in high-grade primary tumor patients with papillary serous tumors of the ovary. To determine whether increased levels or mutation of PPP2R1A might contribute to cancer progression, the effects of overexpression or mutation of PPP2R1A on cell proliferation, migration, and PP2A phosphatase activity were investigated using ovarian and endometrial cancer cell lines. Among the mutations, PPP2R1A-W257G enhanced cell migration in vitro through activating SRC-JNK-c-Jun pathway. Overexpression of wild type (WT) PPP2R1A increased its binding ability with B56 regulatory subunits, whereas PPP2R1A-mutations lost the ability to bind to most B56 subunits except B56δ. Total PP2A activity and PPP2R1A-associated PP2Ac activity were significantly increased in cells overexpressing PPP2R1A-WT. In addition, overexpression of PPP2R1A-WT increased cell proliferation in vitro and tumor growth in vivo.
Assuntos
Sistema de Sinalização das MAP Quinases , Mutação , Metástase Neoplásica/genética , Proteína Fosfatase 2/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Proliferação de Células , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Feminino , Humanos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , FosforilaçãoRESUMO
Aurora B activation is triggered at the mitotic entry and required for proper microtubule-kinetochore attachment at mitotic phase. Therefore, Aurora B should be in inactive form in interphase to prevent aberrant cell cycle progression. However, it is unclear how the inactivation of Aurora B is sustained during interphase. In this study, we find that IK depletion-induced mitotic arrest leads to G2 arrest by Aurora B inhibition, indicating that IK depletion enhances Aurora B activation before mitotic entry. IK binds to Aurora B, and colocalizes on the nuclear foci during interphase. Our data further show that IK inhibits Aurora B activation through recruiting PP2A into IK and Aurora B complex. It is thus believed that IK, as a scaffold protein, guides PP2A into Aurora B to suppress its activity in interphase until mitotic entry.
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Aurora Quinase B/metabolismo , Citocinas/metabolismo , Proteína Fosfatase 2/metabolismo , Aurora Quinase B/antagonistas & inibidores , Benzamidas/farmacologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Ativação Enzimática/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Interfase , Pontos de Checagem da Fase M do Ciclo Celular , Fosforilação/efeitos dos fármacos , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Tubulina (Proteína)/metabolismoRESUMO
Complement-C1q/tumor necrosis factor-α related protein 1 (CTRP1) is a 35-kDa glycoprotein that is secreted from various tissues. Although CTRP1 is highly increased in patients with type II diabetes and obesity, the metabolic roles of CTRP1 remain largely unknown. To unveil the physiological roles of CTRP1 in vivo, CTRP1 transgenic (TG) mice were challenged by a high-fat diet (HFD) and a high-sucrose drink (HS). Homeostatic model assessment-estimated insulin resistance values were decreased in HFD- or HS-fed CTRP1 TG mice compared with wild-type control mice. In this context, CTRP1 stimulated glucose uptake through the glucose transporter GLUT4 translocation to the plasma membrane and also increased glucose consumption by stimulating glycolysis. To analyze the roles of CTRP1 in lipid metabolism, acetyl-CoA carboxylase (ACC) and hormone-sensitive lipase levels were determined in CTRP1 TG mice, and the effect of CTRP1 on fatty acid oxidation was assessed in C2C12 myotubes. CTRP1 was found to inhibit ACC by phosphorylation and to stimulate fatty acid oxidation in C2C12 myotubes. Taken together, CTRP1 performs active catabolic roles in vivo. Therefore, CTRP1 seems to perform a defensive function against nutritional challenges.
Assuntos
Adipocinas/fisiologia , Dieta , Ácidos Graxos/metabolismo , Hiperglicemia/prevenção & controle , Células 3T3-L1 , Animais , Dieta Hiperlipídica , Metabolismo Energético , Glicólise , Hiperglicemia/etiologia , Camundongos , Músculo Esquelético/metabolismo , OxirreduçãoRESUMO
Extracts from Asian medicinal herbs are known to be successful therapeutic agents against cancer. In this study, the effects of three types of herbal extracts on anti-tumor growth were examined. Among the three types of herbal extracts, H9 showed stronger anti-tumor growth effects than H5 and H11 in vivo. To find the molecular mechanism by which H9 inhibited the proliferation of breast cancer cell lines, the levels of apoptotic markers were examined. Proapoptotic markers, including cleaved PARP and cleaved caspases 3 and 9, were increased, whereas the anti-apoptotic marker Bcl-2 was decreased by H9 treatment. Next, the combined effect of H9 with the chemotherapeutic drugs doxorubicin/cyclophosphamide (AC) on tumor growth was examined using 4T1-tumor-bearing mice. The combined treatment of H9 with AC did not show additive or synergetic anti-tumor growth effects. However, when tumor-bearing mice were co-treated with H9 and the targeted anti-tumor drug trastuzumab, a delay in tumor growth was observed. The combined treatment of H9 and trastuzumab caused an increase of natural killer (NK) cells and a decrease of myeloid-derived suppressor cells (MDSC). Taken together, H9 induces the apoptotic death of tumor cells while increasing anti-tumor immune activity through the enhancement of NK activity and diminishment of MDSC.
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Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Preparações de Plantas/uso terapêutico , Trastuzumab/uso terapêutico , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Camundongos , Neoplasias/imunologia , Preparações de Plantas/farmacologia , Trastuzumab/farmacologia , Resultado do TratamentoRESUMO
IL-32ß is highly expressed and increases the migration and invasion of gastric, lung, and breast cancer cells. Since IL-32 enhances VEGF production under hypoxic conditions, whether IL-32ß is regulated by hypoxia was examined. Hypoxic conditions and a mimetic chemical CoCl2 enhanced IL-32ß production. When cells were treated with various inhibitors of ROS generation to prevent hypoxia-induced ROS function, IL-32ß production was suppressed by both NADPH oxidase and mitochondrial ROS inhibitors. IL-32ß translocated to the mitochondria under hypoxic conditions, where it was associated with mitochondrial biogenesis. Thus, whether hypoxia-induced IL-32ß is associated with oxidative phosphorylation (OXPHOS) or glycolysis was examined. Glycolysis under aerobic and anaerobic conditions is impaired in IL-32ß-depleted cells, and the hypoxia-induced IL-32ß increased glycolysis through activation of lactate dehydrogenase. Src is also known to increase lactate dehydrogenase activity, and the hypoxia-induced IL-32ß was found to stimulate Src activation by inhibiting the dephosphorylation of Src. These findings revealed that a hypoxia-ROS-IL-32ß-Src-glycolysis pathway is associated with the regulation of cancer cell metabolism.
Assuntos
Neoplasias da Mama/tratamento farmacológico , Glicólise , Hipóxia , Interleucinas/metabolismo , Mitocôndrias/metabolismo , Western Blotting , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Metabolismo Energético , Feminino , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Interleucinas/antagonistas & inibidores , Interleucinas/genética , Potencial da Membrana Mitocondrial , Fosforilação Oxidativa , RNA Interferente Pequeno/genética , Células Tumorais Cultivadas , Quinases da Família src/metabolismoRESUMO
IK is known to inhibit the expression of major histocompatibility complex (MHC) class II antigen, but other cellular functions of IK remain to be uncovered. In this study, IK depletion caused misalignment of chromosomes through an increase in Aurora A and PLK1 phosphorylation, which was mediated by a decrease in PP1 and PP2A activities. On the other hand, the treatment of a dual inhibitor against CDK and Aurora kinases overrode IK depletion-induced mitotic arrest through the activation of phosphatase activity. These findings imply that IK is an essential protein for achieving correct mitotic progress through the regulation of mitotic kinases and phosphatases.
Assuntos
Aurora Quinase A/metabolismo , Pontos de Checagem do Ciclo Celular , Citocinas/deficiência , Mitose , Fosfoproteínas Fosfatases/metabolismo , Animais , Apoptose , Sequência de Bases , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Citocinas/genética , Citocinas/metabolismo , Inativação Gênica , Humanos , Camundongos , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , RNA Interferente Pequeno/genética , Quinase 1 Polo-LikeRESUMO
Cancerous inhibitor of protein phosphatase 2A (CIP2A) is overexpressed in most human cancers and has been described as being involved in the progression of several human malignancies via the inhibition of protein phosphatase 2A (PP2A) activity toward c-Myc. However, with the exception of this role, the cellular function of CIP2A remains poorly understood. On the basis of yeast two-hybrid and coimmunoprecipitation assays, we demonstrate here that NIMA (never in mitosis gene A)-related kinase 2 (NEK2) is a binding partner for CIP2A. CIP2A exhibited dynamic changes in distribution, including the cytoplasm and centrosome, depending on the cell cycle stage. When CIP2A was depleted, centrosome separation and the mitotic spindle dynamics were impaired, resulting in the activation of spindle assembly checkpoint signaling and, ultimately, extension of the cell division time. Our data imply that CIP2A strongly interacts with NEK2 during G2/M phase, thereby enhancing NEK2 kinase activity to facilitate centrosome separation in a PP1- and PP2A-independent manner. In conclusion, CIP2A is involved in cell cycle progression through centrosome separation and mitotic spindle dynamics.
Assuntos
Autoantígenos/metabolismo , Divisão Celular/fisiologia , Centrossomo/metabolismo , Fase G2/fisiologia , Proteínas de Membrana/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Autoantígenos/genética , Pontos de Checagem do Ciclo Celular/fisiologia , Citoplasma/genética , Citoplasma/metabolismo , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Camundongos , Quinases Relacionadas a NIMA , Proteína Fosfatase 1/genética , Proteína Fosfatase 1/metabolismo , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/fisiologia , Técnicas do Sistema de Duplo-HíbridoRESUMO
Cancerous inhibitor of PP2A (CIP2A) stimulates the proliferation of various cancer cells, and 17ß-estradiol (E2) enhances the proliferation of breast cancer cells. E2 activates epidermal growth factor receptor (EGFR), stimulating the MEK1/2 and PI3K pathways, and CIP2A expression is increased by the MEK1/2-induced transcription factor ETS1. It is possible for E2 to increase CIP2A expression. This study examined whether E2 could increase CIP2A expression and whether CIP2A is highly expressed in estrogen receptor (ER)-positive breast cancer tissues. E2 increased CIP2A expression at the translational level in a c-MYC-independent manner in MCF-7 cells. E2-enhanced proliferation was impaired without CIP2A expression. E2-stimulated EGFR activated the MAPK and PI3K pathways, which converged to activate p70 S6 kinase (S6K). Phosphorylation at all the three phosphorylation sites (S424/T421, T229, and T389) on S6K was required for the phosphorylation of eukaryotic initiation factor 4B (eIF4B), which was responsible for the increase in CIP2A translation. Furthermore, CIP2A expression was higher in ER-positive tissues than in ER-negative tissues. This is the first study, to our knowledge, to demonstrate that CIP2A is a key factor in E2-enhanced proliferation and that estrogen regulates CIP2A expression by non-genomic action through EGFR.