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Incense-burning smoke is a deleterious air pollutant that initiates cytotoxic effects by inducing apoptosis in lung epithelial cells and also acts as a risk factor for lung cancers. Auramine, an ingredient of incense smoke, has been implicated in tumor progression and cellular sensitivity in non-small cell lung cancer (NSCLC) towards anti-cancer agents through unclear mechanisms. Tumor protein p53 (TP53)-activated long intergenic non-coding RNA-p21 (lincRNA-p21) undertakes a pivotal role in regulating cell apoptosis and chemosensitivity. TP53 mutations prevalent in 50% of NSCLC, contribute to diminished therapeutic efficacy. However, the influence of auramine on chemotherapy-induced lincRNA-p21 expression and apoptosis in NSCLC with different TP53 genetic statuses remains unexplored. This study disclosed that both wild-type p53 (wtp53) and mutant p53 (mutp53) mediate lincRNA-p21 expression, albeit through distinct promoter enhancers, p53-response element (p53RE) and non-B DNA structure G-quadruplex (GQ), respectively. Intriguingly, auramine functions as an effective stabilizer of the GQ structure, augmenting mutp53-mediated lincRNA-p21 expression and enhancing apoptosis and cellular sensitivity to chemotherapy in mutp53-expressing NSCLC cells. These findings suggest a mechanism by which mutp53, in the presence of auramine, is endowed with tumor-suppressing function akin to wtp53, thereby aiding in combating chemoresistance in NSCLC cells harboring TP53 mutations.
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Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Mutación , ARN Largo no Codificante , Proteína p53 Supresora de Tumor , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Mutación/efectos de los fármacos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Humo/efectos adversos , Línea Celular Tumoral , Resistencia a Antineoplásicos/efectos de los fármacosRESUMEN
Naturally occurring 6-pentyl-2H-pyran-2-one and its synthetic analogues greatly inhibit the settlement of Amphibalanus amphitrite cyprids and the growth and biofilm formation of marine bacteria. To optimize the antifouling activities of pyrone derivatives, this study designed pyrone analogues by modifying functional groups, such as the benzyl group, cyclopentane, and halides, substituted on both sides of a pyrone. The antifouling effects of the synthesized pyrone derivatives were subsequently evaluated against five marine biofilm-forming bacteria, Loktanella hongkongensis, Staphylococcus cohnii, S. saprophyticus, Photobacterium angustum, and Alteromonas macleodii, along with barnacle cyprids of Amphibalanus amphitrite. Substituting nonpolar parts-such as the aliphatic, cyclopentyl, or phenyl moieties on C-5 or the furan moieties on C-3-not only increased antibacterial activity and inhibited biofilm formation but also inhibited barnacle cyprid settlement when compared to 6-pentyl-2H-pyran-2-one.
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Tumour hypoxia plays an important role in modulating tumorigenesis, angiogenesis, invasion, immunosuppression, resistance to treatment, and even maintenance of the stemness of cancer stem cells (CSCs). Moreover, the targeting and treatment of hypoxic cancer cells and CSCs to reduce the influence of tumor hypoxia on cancer therapy remains an imperative clinical problem that needs to be addressed. Since cancer cells upregulate the expression of glucose transporter 1 (GLUT1) through the Warburg effect, we considered the possibility of GLUT1-mediated transcytosis in cancer cells and developed a tumor hypoxia-targeting nanomedicine. Our experimental results indicate that glucosamine-labeled liposomal ceramide can be efficiently transported between cancer cells by GLUT1 transporters and substantially accumulated in the hypoxic area in in vitro CSC spheroids and in vivo tumor xenografts. We also verified the effects of exogenous ceramide on tumor hypoxia, including important bioactivities such as upregulation of p53 and retinoblastoma protein (RB), downregulation of hypoxia-inducible factor-1 alpha (HIF-1α) expression, disruption of the OCT4-SOX2 network of stemness, and inhibition of CD47 and PD-L1 expression. To achieve an ideal therapeutic outcome, we combined treatment of glucosamine-labeled liposomal ceramide with paclitaxel and carboplatin, and we found an excellent synergistic effect, with tumor clearance being noted in three-fourths of the mice. Overall, our findings provide a potential therapeutic strategy for the treatment of cancer.
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Hipoxia , Neoplasias , Humanos , Ratones , Animales , Transportador de Glucosa de Tipo 1/metabolismo , Hipoxia/metabolismo , Hipoxia de la Célula , Liposomas/farmacología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Transcitosis , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Línea Celular Tumoral , Neoplasias/patologíaRESUMEN
The surface-assisted laser desorption/ionization (SALDI) technique uses inorganic materials to aid desorption and ionization of molecules. SALDI is suitable for analyzing small molecules due to the absence of interfering signals in the low m/z range originating from the organic matrix. Imaging mass spectrometry (IMS) is a versatile imaging approach with high spatial resolution for analyzing various molecular species, but its application depends heavily on the ionization method. We have developed a functionalized titanium dioxide (TiO2) nanowire as a solid substrate for SALDI-MS detection of low-molecular-weight molecules. We apply this novel substrate for imprinting fragile specimens such as petals and further SALDI-IMS analysis. The TiO2 nanowire substrate is prepared from a commercial Ti plate by a hydrothermal process and subsequently chemically modified to improve the quality and selectivity of imprinting as well as the sensitivity of SALDI-IMS analysis. Here, the functionalized TiO2 nanowire substrate is applied to visualize the distribution of vinca alkaloids in the petal of Madagascar periwinkle (Catharanthus roseus).
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Catharanthus , Alcaloides de la Vinca , Diagnóstico por Imagen/métodos , Rayos Láser , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodosRESUMEN
Bacterial polyynes are highly active natural products with a broad spectrum of antimicrobial activities. However, their detailed mechanism of action remains unclear. By integrating comparative genomics, transcriptomics, functional genetics, and metabolomics analysis, we identified a unique polyyne resistance gene, masL (encoding acetyl-CoA acetyltransferase), in the biosynthesis gene cluster of antifungal polyynes (massilin A 1, massilin B 2, collimonin C 3, and collimonin D 4) of Massilia sp. YMA4. Crystallographic analysis indicated that bacterial polyynes serve as covalent inhibitors of acetyl-CoA acetyltransferase. Moreover, we confirmed that the bacterial polyynes disrupted cell membrane integrity and inhibited the cell viability of Candida albicans by targeting ERG10, the homolog of MasL. Thus, this study demonstrated that acetyl-CoA acetyltransferase is a potential target for developing antifungal agents.
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Acetil-CoA C-Acetiltransferasa , Antifúngicos , Acetil-CoA C-Acetiltransferasa/genética , Acetil-CoA C-Acetiltransferasa/metabolismo , Antifúngicos/farmacología , Bacterias/metabolismo , Candida albicans/genética , Candida albicans/metabolismo , Poliinos/metabolismo , Poliinos/farmacologíaRESUMEN
The proviral integration site for moloney murine leukemia virus 1 (Pim1) is a serine/threonine kinase and able to promote cell proliferation, survival and drug resistance. Overexpression of Pim1 has been observed in many cancer types and is associated with the poor prognosis of breast cancer. However, it remains unclear whether Pim1 kinase is a potential therapeutic target for breast cancer patients. In this study, we found that Pim1 expression was strongly associated with HER2 expression and that HER2-overexpressing breast cancer cells were more sensitive to Pim1 inhibitor-induced inhibitions of cell viability and metastatic ability. Mechanistically, Pim1 inhibitor suppressed the expression of HER2 at least in part through transcriptional level. More importantly, Pim1 inhibitor overcame the resistance of breast cancer cells to HER2 tyrosine kinase inhibitor lapatinib. In summary, downregulation of HER2 by targeting Pim1 may be a promising and effective therapeutic approach not only for anti-cancer growth but also for circumventing lapatinib resistance in HER2-positive breast cancer patients.
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The tyrosine kinase inhibitors (TKIs) targeting epidermal growth factor receptor (EGFR) have been widely used for non-small cell lung cancer (NSCLC) patients, but the development of acquired resistance remains a therapeutic hurdle. The reduction of glucose uptake has been implicated in the anti-tumor activity of EGFR TKIs. In this study, the upregulation of the active sodium/glucose co-transporter 1 (SGLT1) was found to confer the development of acquired EGFR TKI resistance and was correlated with the poorer clinical outcome of the NSCLC patients who received EGFR TKI treatment. Blockade of SGLT1 overcame this resistance in vitro and in vivo by reducing glucose uptake in NSCLC cells. Mechanistically, SGLT1 protein was stabilized through the interaction with PKCδ-phosphorylated (Thr678) EGFR in the TKI-resistant cells. Our findings revealed that PKCδ/EGFR axis-dependent SGLT1 upregulation was a critical mechanism underlying the acquired resistance to EGFR TKIs. We suggest co-targeting PKCδ/SGLT1 as a potential strategy to improve the therapeutic efficacy of EGFR TKIs in NSCLC patients.
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Carcinoma de Pulmón de Células no Pequeñas , Transportador 1 de Sodio-Glucosa , Regulación hacia ArribaRESUMEN
Biofouling is a widespread phenomenon in oceans worldwide. With increasing human development and activities in open and coastal waters, and due to the environmental impact of AF organotins and copper-based paint, the demand for nontoxic antifouling (AF) paints is increasing. Various bioassays for antimicrobial activity, anti-biofilm formation and anti-barnacle settlement were established to evaluate the possibility of using marine natural products as AF agents. A series of natural products, isolated from the marine-derived fungi Trichoderma atroviride and T. reesei, were evaluated for their AF activity. One pyrone-type compound (1) demonstrated significant inhibitory activities toward barnacle cyprid settlement. Furthermore, a series of pyrone analogues (S1-S6) were synthesized, and their bioactivities were evaluated in the established systems. The results showed that compounds S5 and S6 exhibited a broad spectrum of bioactivities, such as anti-barnacle settlement, anti-biofilm formation and antimicrobial activities.
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Incrustaciones Biológicas , Policétidos , Incrustaciones Biológicas/prevención & control , Humanos , Hypocreales , Océanos y Mares , Pironas/farmacologíaRESUMEN
Bacteria and fungi secrete many natural products that inhibit each other's growth and development. The dynamic changes in secreted metabolites that occur during interactions between bacteria and fungi are complicated. Pyochelin is a siderophore produced by many Pseudomonas and Burkholderia species that induces systemic resistance in plants and has been identified as an antifungal agent. Through imaging mass spectrometry and metabolomics analysis, we found that Phellinus noxius, a plant pathogen, can modify pyochelin and ent-pyochelin to an esterification product, resulting in reduced iron-chelation and loss of antifungal activity. We also observed that dehydroergosterol peroxide, the fungal metabolite, is only accumulated in the presence of pyochelin produced through bacteria-fungi interactions. For the first time, we show the fungal transformation of pyochelin in the microbial interaction. Our findings highlight the importance of understanding the dynamic changes of metabolites in microbial interactions and their influences on microbial communities.
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Antifúngicos , Sideróforos , Antifúngicos/farmacología , Hongos , Hierro , Pseudomonas , Pseudomonas aeruginosaRESUMEN
Smoker patients with non-small cell lung cancer (NSCLC) have poorer prognosis and survival than those without smoking history. However, the mechanisms underlying the low response rate of those patients to EGFR tyrosine kinase inhibitors (TKIs) are not well understood. Here we report that exposure to cigarette smoke extract enhances glycolysis and attenuates AMP-activated protein kinase (AMPK)-dependent inhibition of mTOR; this in turn reduces the sensitivity of NSCLC cells with wild-type EGFR (EGFRWT) to EGFR TKI by repressing expression of liver kinase B1 (LKB1), a master kinase of the AMPK subfamily, via CpG island methylation. In addition, LKB1 expression is correlated positively with sensitivity to TKI in patients with NSCLC. Moreover, combined treatment of EGFR TKI with AMPK activators synergistically increases EGFR TKI sensitivity. Collectively, the current study suggests that LKB1 may serve as a marker to predict EGFR TKI sensitivity in smokers with NSCLC carrying EGFRWT and that the combination of EGFR TKI and AMPK activator may be a potentially effective therapeutic strategy against NSCLC with EGFRWT.
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Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/genética , Serina-Treonina Quinasas TOR/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Carcinoma de Pulmón de Células no Pequeñas/inducido químicamente , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Fumar Cigarrillos/efectos adversos , Islas de CpG/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Receptores ErbB/genética , Xenoinjertos , Humanos , Ratones , Mutación/genética , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/genética , Transducción de Señal/efectos de los fármacos , Fumar/efectos adversosRESUMEN
To improve simulation accuracy and efficiency of probabilistic fatigue life evaluation for turbine rotor, a decomposed collaborative modeling approach is presented. In this approach, the intelligent Kriging modeling (IKM) is firstly proposed by combining the Kriging model (KM) and an intelligent algorithm (named as dynamic multi-island genetic algorithm), to tackle the multi-modality issues for obtaining optimal Kriging parameters. Then, the decomposed collaborative IKM (DCIKM) comes up by fusing the IKM into decomposed collaborative (DC) strategy, to address the high-nonlinearity problems for accelerating simulation efficiency. Moreover, the DCIKM-based probabilistic fatigue life evaluation theory is introduced. The probabilistic fatigue life evaluation of turbine rotor is regarded as case study to verify the presented approach; the evaluation results reveal that the probabilistic fatigue life of turbine rotor is 3296 cycles. The plastic strain range ∆εp and fatigue strength coefficient σf' are the main affecting factors to fatigue life, whose effect probability are 28% and 22%, respectively. By comparing with direct Monte Carlo method, KM method, IKM method and DC response surface method, the presented DCIKM is validated to hold high efficiency and accuracy in probabilistic fatigue life evaluation.
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Betacoronavirus , Infecciones por Coronavirus , Enfermedades Musculoesqueléticas , Pandemias , Neumonía Viral , COVID-19 , Consenso , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/prevención & control , Epidemias , Humanos , Procedimientos Quirúrgicos Mínimamente Invasivos , Enfermedades Musculoesqueléticas/complicaciones , Enfermedades Musculoesqueléticas/terapia , Pandemias/prevención & control , Neumonía Viral/complicaciones , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , SARS-CoV-2RESUMEN
BACKGROUND: The osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) is critical for bone homeostasis. Here, we investigated the regulation of Galectin-3 and tripartite motif protein 16 (TRIM16) on osteogenic differentiation of hBMSCs through autophagy. METHODS: Quantitative PCR (qPCR) and western blot were performed to determine the expression of osteogenic markers, autophagic markers, Galectin-3 and TRIM16. Short-hairpin RNAs (shRNAs) and overexpression plasmids were used to manipulate the expression of Galectin-3, TRIM16 and Unc-51 like autophagy activating kinase 1 (ULK1). Alkaline phosphatase (ALP) activity was measured by ALP staining assay. Calcium deposition in differentiated hBMSCs was assessed by Alizarin Red S staining. LC3 puncta formation was monitored by immunofluorescence staining. The interaction between indicated proteins was confirmed by co-immunoprecipitation (Co-IP) assay. RESULTS: Either Galectin-3 or TRIM16 knockdown led to impaired ALP activity, reduced calcium deposition, down-regulation of pro-osteogenic markers as well as restrained autophagy in osteogenic-induced hBMSCs. However, overexpression of Galectin-3 or TRIM16 promoted osteogenic differentiation of hBMSCs, which was then compromised by autophagy inhibition. Co-IP experiment demonstrated that TRIM16 associated with Galectin-3 through ULK1. Meanwhile, osteogenic induction enhanced the association between TRIM16 and ULK1 or coiled-coil myosin-like BCL2-interacting protein (Beclin1), and TRIM16 increased the stability of ULK1 and Beclin1. Moreover, either TRIM16 or ULK1 knockdown dampened the pro-osteogenic effect of Galectin-3, which elucidated that Galectin-3 mediated osteogenic differentiation was at least partly dependent on TRIM16 and ULK1. CONCLUSION: In summary, the present study revealed Galectin-3 and TRIM16 co-regulated osteogenic differentiation of hBMSCs at least partly via enhancing autophagy, which might provide a promising approach for osteoporosis treatment in future.
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Galectina 3 , Células Madre Mesenquimatosas , Osteogénesis , Proteínas de Motivos Tripartitos , Ubiquitina-Proteína Ligasas , Autofagia , Médula Ósea , Diferenciación Celular , Células Cultivadas , Galectina 3/genética , Humanos , Células Madre Mesenquimatosas/citologíaRESUMEN
OBJECTIVE: Chondrocyte apoptosis has also been strongly correlated with the severity of cartilage damage and matrix depletion in an osteoarthritis (OA) joint. Therefore, pharmacological inhibitors of apoptosis may provide a novel treatment option for patients with OA. Aucubin, a natural compound isolated from Eucommia ulmoides, has been proved to possess antioxidative and anti-apoptotic properties. However, anti-osteoarthritis effect of aucubin in animal model and anti-apoptotic response of aucubin in OA chondrocytes remain unclear. This study aimed to determine whether aucubin could slow progression of OA in a mouse model and inhibit the IL-1ß-induced chondrocyte apoptosis. METHODS: OA severity and articular cartilage degradation were evaluated by Safranin-O staining, Hematoxylin-eosin (H&E) staining, and Osteoarthritis Research Society International (OARSI) standards. Chondrocyte viability was observed by Cell Counting Kit-8 (CCK8) and live/dead cells assay; the apoptotic rate of chondrocytes was evaluated by flow cytometry (FCM) with Annexin V-FITC/PI kit. Mediators of apoptosis were tested by Western blot of Bax, caspase-3, caspase-9, and Bcl-2 expression. The intracellular levels of Reactive oxygen species (ROS) were assessed by the probe of 2,7-Dichlorofluorescin diacetate (DCFH-DA). RESULTS: The articular cartilage in the limb with destabilization of the medial meniscus (DMM) exhibited early OA-like manifestations characterized by proteoglycan loss, cartilage fibrillation, and erosion, with lower OARSI score. Oral administration of aucubin remarkably attenuated the loss of proteoglycan and the articular cartilage erosion and decreased the OARSI scores underwent DMM surgery. Aucubin treatment significantly reverses IL-1ß-induced cytotoxicity and attenuated the IL-1ß-induced chondrocyte apoptosis. In addition, aucubin can significantly inhibit mediators of apoptosis in rat primary chondrocytes. Furthermore, aucubin remarkably attenuated the IL-1ß-induced intracellular ROS production. CONCLUSION: Our findings suggest that aucubin has a protective effect on articular cartilage and slowing progression of OA in a mouse model. This protective effect may result from inhibiting chondrocyte apoptosis and excessive ROS production.
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Apoptosis/efectos de los fármacos , Condrocitos/efectos de los fármacos , Modelos Animales de Enfermedad , Interleucina-1beta/metabolismo , Glucósidos Iridoides/farmacología , Osteoartritis/tratamiento farmacológico , Sustancias Protectoras/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Condrocitos/metabolismo , Relación Dosis-Respuesta a Droga , Masculino , Ratones , Ratones Endogámicos C57BL , Osteoartritis/metabolismo , Osteoartritis/patología , Ratas , Ratas Sprague-Dawley , Relación Estructura-ActividadRESUMEN
Currently, accurate diagnosis and successful treatment of infection after fracture fixation (IAFF) still impose great challenges. According to the onset of infection symptoms after implantation, IAFF is classified as early infection (<2 weeks), delayed infection (2â¼10 weeks) and late infection (>10 weeks). Confirmation of IAFF should be supported by histopathological tests of intraoperative specimens which confirm infection, cultures from at least two suspected infection sites which reveal the same pathogen, a definite sinus or fistula which connects directly the bone or the implant, and purulent drainage from the wound or presence of pus during surgery. Diagnosis of IAFF is built on comprehensive assessment of medical history, clinical signs and symptoms of the patient, and imaging and laboratory tests. The gold standard of diagnosis is histopathological tests. Treatment of IAFF consists of radical debridement, adequate irrigation, implant handling, systematic and local antibiotics, reconstruction of osseous and/or soft tissue defects, and functional rehabilitation of an affected limb. Early accurate diagnosis and appropriate treatment of IAFF play a key role in increasing the cure rate, reducing infection recurrence and disability risk, restoring limb function and improving quality of life of the patient.
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Consenso , Fijación de Fractura/efectos adversos , Fracturas Óseas/cirugía , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones de los Tejidos Blandos/diagnóstico , Infección de la Herida Quirúrgica/diagnóstico , Cicatrización de Heridas/fisiología , Antibacterianos/uso terapéutico , Biopelículas , China , Desbridamiento/métodos , Fracturas Óseas/complicaciones , Humanos , Guías de Práctica Clínica como Asunto , Infecciones Relacionadas con Prótesis/terapia , Procedimientos de Cirugía Plástica/métodos , Infecciones de los Tejidos Blandos/terapia , Infección de la Herida Quirúrgica/terapia , Rayos XAsunto(s)
Aromatasa/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias Hipofisarias/patología , Posmenopausia , Prolactinoma/patología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias Hipofisarias/enzimología , Pronóstico , Prolactinoma/enzimologíaRESUMEN
By an ESI-LC/MS analytical method, a racemate 1 consisting of a pair of unprecedented phloroglucinol enantiomers with a 5/6/5/5/6 fused ring system, (-)-garcinielliptone HG [((-)-1a] and (+)-garcinielliptone HH [(+)-1b], was obtained from the isolates of a CH2Cl2 extract of Garcinia subelliptica (heartwood). The gross structure of 1 was elucidated by spectroscopic methods and X-ray single-crystal diffraction data. The absolute configurations of 1a and 1b were unequivocally assigned by analysis on the calculated and experimental circular dichroism spectra and X-ray single-crystal diffraction data.
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BACKGROUND: miR-193a has been shown to be involved in a variety of biological processes, including cell proliferation, differentiation, and apoptosis. However, little is known about how miR-193a regulates osteogenic differentiation. METHODS: We employed RT-qPCR to determine the level of miR-193a and mRNA level of HMGB1 and osteoblast-specific markers (Runx2, ALP, OSX, OCN). Besides, westernblot was used to probe protein level of phosphorylated MAPK family members and ß-catenin. Bioinformatic analysis was used to predict the putative binding sequence of miR-193a to the 3'-UTR of HMGB1 and we confirmed this result by dual luciferase reporter assay. Alizarin red staining assay (ARS) and alkaline phosphatase activity (ALP) were performed to detect osteogenic differentiation. RESULTS: miR-193a was downregulated in OM (osteogenic medium)induced hBMSC. More interestingly, we found that miR-193a mimic attenuated matrix mineralization and alkaline phosphatase activity, whereas miR-193a inhibitor exerted the opposite phenotypes. Mechanistically, we observed that miR-193a played an inhibitory role in expression of osteoblast-specific markers and activation of MAPK and Wnt signaling pathways. Bioinformatic analysis and dual luciferase assay demonstrated that miR-193a directly targeted 3'-UTR of HMGB1. Furthermore, we overexpressed HMGB1 in miR-193a overexpressed hBMSC to establish that HMGB1 acted as downstream target of miR-193a-inhibited osteogenic differentiation. CONCLUSIONS: Here, we reveal miR-193a plays a suppressive role in osteogenic differentiation of hBMSC via targeting HMGB1. These findings provide a novel mechanism underlying osteogenic differentiation and offer therapeutical strategy for bone formation.
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Proteína HMGB1/genética , Células Madre Mesenquimatosas/citología , MicroARNs/genética , Osteoblastos/citología , Osteogénesis , Diferenciación Celular , Células Cultivadas , Regulación hacia Abajo , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Células Madre Mesenquimatosas/metabolismo , Osteoblastos/metabolismo , Regulación hacia Arriba , Vía de Señalización WntRESUMEN
Cigarette smoking is one of the leading risks for lung cancer and is associated with the insensitivity of non-small cell lung cancer (NSCLC) to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, it remains undetermined whether and how cigarette smoke affects the therapeutic efficacy of EGFR TKIs. In this study, our data showed that chronic exposure to cigarette smoke extract (CSE) or tobacco smoke-derived carcinogen benzo[α]pyrene, B[α]P, but not nicotine-derived nitrosamine ketone (NNK), reduced the sensitivity of wild-type EGFR-expressing NSCLC cells to EGFR TKIs. Treatment with TKIs almost abolished EGFR tyrosine kinase activity but did not show an inhibitory effect on downstream Akt and ERK pathways in B[α]P-treated NSCLC cells. CSE and B[α]P transcriptionally upregulate c-MET and activate its downstream Akt pathway, which is not inhibited by EGFR TKIs. Silencing of c-MET reduces B[α]P-induced Akt activation. The CSE-treated NSCLC cells are sensitive to the c-MET inhibitor crizotinib. These findings suggest that cigarette smoke augments oncogene addiction to c-MET in NSCLC cells and that MET inhibitors may show clinical benefits for lung cancer patients with a smoking history.
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Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Oncogenes , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-met/metabolismo , Fumar/efectos adversos , Benzo(a)pireno , Línea Celular Tumoral , Receptores ErbB/metabolismo , Células HEK293 , Humanos , Modelos Biológicos , Mutación/genética , Proteínas Proto-Oncogénicas c-akt/metabolismoRESUMEN
Aimed to investigate the characteristics of CS-induced membrane in comparison with the PMMA-induced membrane. Cellular components, histological changes, growth factor expressions of IL-6, VEGF, BMP-2, and TGF-ß1 in the two induced membranes were compared at 2, 4, 6 and 8 weeks, respectively. We also compared the histological changes at the bone defects between CS and PMMA groups. The structural characteristics of induced membrane were similar between CS and PMMA. Endochondral ossification took place in the CS-induced membrane at 8 week. Levels of VEGF, BMP-2 and TGF-ß1 in CS-induced membrane were insignificantly higher than those in PMMA-induced membrane at different time points. The expression of IL-6 was significantly higher in PMMA-induced membranes at 2nd week. In addition, osteogenic and neovascular activities of induced membranes increased with time and peaked at 6 weeks. CS promoted endochondral ossification at the broken ends of the bone defect than PMMA did. CS-induced membrane has a better capacity of generating VEGF, BMP-2 and TGF-ß1.osteogenic and neovascular activities achieve highest level at 6 week. CS may have the potential to replace PMMA as a novel spacer in Masquelet technique.