RESUMO
Cisplatin (CDDP) is a commonly used chemotherapeutic for osteosarcoma (OS) patients, and drug resistance remains as a major hurdle to undermine the treatment outcome. Here, we investigated the potential involvement of FoxG1 and BNIP3 in CDDP resistance of OS cells. FoxG1 and BNIP3 expression levels were detected in the CDDP-sensitive and CDDP-resistant OS tumors and cell lines. Mitophagy was observed through transmission electron microscope analysis. The sensitivity to CDDP in OS cells upon FoxG1 overexpression was examined in cell and animal models. We found that FoxG1 and BNIP3 showed significant downregulation in the CDDP-resistant OS tumor samples and cell lines. CDDP-resistant OS tumor specimens and cells displayed impaired mitophagy. FoxG1 overexpression promoted BNIP3 expression, enhanced mitophagy in CDDP-resistant OS cells, and resensitized the resistant cells to CDDP treatment in vitro and in vivo. Our data highlighted the role of the FoxG1/BNIP3 axis in regulating mitophagy and dictating CDDP resistance in OS cells, suggesting targeting FoxG1/BNIP3-dependent mitophagy as a potential strategy to overcome CDDP resistance in OS.
Assuntos
Neoplasias Ósseas , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Fatores de Transcrição Forkhead , Proteínas de Membrana , Mitofagia , Proteínas do Tecido Nervoso , Osteossarcoma , Proteínas Proto-Oncogênicas , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Osteossarcoma/genética , Mitofagia/efeitos dos fármacos , Cisplatino/farmacologia , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Animais , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/genética , Linhagem Celular Tumoral , Camundongos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Neoplasias Ósseas/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/genética , Feminino , Masculino , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
BACKGROUND: Cisplatin (CDDP) is a mainstay chemotherapeutic agent for OS treatment, but drug resistance has become a hurdle to limit its clinical effect. Autophagy plays an important role in CDDP resistance in OS, and in the present study we explored the role of ANXA2 and Rac1 in dictating CDDP sensitivity in OS cells. METHODS: ANXA2 and Rac1 expression levels were examined by Western blot and autophagy induction was detected by transmission electron miscroscope (TEM) in the clinical samples and OS cell lines. CDDP resistant cells were established by exposing OS cells to increasing doses of CDDP. The effects of ANXA2 and Rac1 knockdown on CDDP sensitivity were evaluated in the cell and animal models. RESULTS: Reduced autophagy was associated with the increased expression of ANXA2 and Rac1 in CDDP resistant OS tumor samples and cells. Autophagy suppression promoted CDDP resistance and inducing autophagy re-sensitized the resistant cells to CDDP treatment in vitro and in vivo. Further, knocking down ANXA2 or Rac1 re-activated autophagy and attenuated CDDP resistance in OS cells. We further demonstrated that CDDP resistant OS cells displayed a poorer osteogenic differentiation state when compared to the parental cell lines, which was significantly reversed by autophagy re-activation and ANXA2 or Rac1 silencing. CONCLUSION: Our findings revealed a complicated interplay of ANXA2/Rac1, autophagy induction, and osteogenic differentiation in dictating CDDP resistance in OS cells, suggesting ANXA2 and Rac1 as promising targets to modulate autophagy and overcome CDDP resistance in OS cells.
Assuntos
Antineoplásicos , Neoplasias Ósseas , Osteossarcoma , Animais , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Osteogênese , Linhagem Celular Tumoral , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Autofagia , Resistencia a Medicamentos Antineoplásicos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , ApoptoseRESUMO
Two Gram-stain-positive, facultatively aerobic, non-motile and rod- to coccoid-shaped bacterial strains, 23H37-10T and 4HC-13, were isolated from the faeces of greater white-fronted geese (Anser albifrons) at Poyang Lake, Jiangxi Province, PR China. Optimal growth was observed at 35-37 °C, pH 7.0-8.0 and with 0.5-1.5â% (w/v) NaCl. The 16S rRNA gene sequences of strains 23H37-10T and 4HC-13 were identical. Phylogenetic and phylogenomic analyses indicated that strains 23H37-10T and 4HC-13 formed an independent cluster within the genus Corynebacterium and showed 98.8, 97.4, 97.4 and 97.2â% 16S rRNA gene sequence similarity to Corynebacterium urogenitale LMM 1652T, Corynebacterium urealyticum DSM 7109T, Corynebacterium falsenii DSM 44353T and Corynebacterium jeikeium NCTC 11913T, respectively. Cells contained C18â:1 ω9c, C18â:â0 and C16â:â0 as the major cellular fatty acids and MK-9 (H2) as the predominant respiratory quinone. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidyl inositol mannosides, two unidentified phospholipids, four unidentified glycolipids and one unidentified lipid. Strain 23H37-10T contained mycolic acids, with meso-diaminopimelic acid and arabinose as the major whole-cell hydrolysates. The genome G+C content of strains 23H37-10T and 4HC-13 was 55.2 mol%. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strains 23H37-10T and 4HC-13 were 94.4 and 99.6â%, respectively. Strains 23H37-10T and 4HC-13 had dDDH and ANI values of less than 70 and 96â% with all available genomes of the genus Corynebacterium, respectively. The differential genotypic inferences, together with phenotypic and biochemical characteristics, suggested that strains 23H37-10T and 4HC-13 represent a novel species within the genus Corynebacterium, for which the name Corynebacterium anserum sp. nov. is proposed. The type strain is 23H37-10T (=GDMCC 1.1737T=KACC 21672T).
Assuntos
Corynebacterium/classificação , Fezes/microbiologia , Gansos/microbiologia , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Corynebacterium/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Lagos , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/químicaRESUMO
Two rod-shaped and Gram-stain-positive bacteria (strains C64T and C62) were isolated in 2020 from faeces of greater white-fronted geese (Anser albifrons) from Poyang Lake, PR China. Their optimal growth conditions were at 37 °C, pH 7.0 and with 0.5â% (w/v) NaCl. The two isolates showed a highest 16S rRNA gene sequence similarity to Bowdeniella nasicola DSM 19116T (92.1â%). Phylogenetic/phylogenomic analyses indicated that strains C64T and C62 clustered independently in the vicinity of the genera Varibaculum, Winkia and Mobiluncus within the family Actinomycetaceae, but could not be classified clearly as members of any of these known genera. The average amino acid identity values between our isolates and available genomes of members of the family Actinomycetaceae were around the genus threshold value (45-65â%). The major cellular fatty acids of the strains were C18â:â1ω9c and C16â:â0. The predominant polar lipids were phosphatidylinositol, phosphatidylglycerol, phosphatidylcholine, diacylglycerol, triacylglycerol and cardiolipin. The amino acid composition of peptidoglycan contained alanine, glutamic acid and glycine. The major respiratory menaquinones were MK-8(H4) and MK-9(H4). The whole cell sugars included galactose, arabinose and glucose. On the basis of the results of the 16S rRNA gene sequences comparison, whole-genome phylogenomic analysis, phenotypic and chemotaxonomic characteristics, we propose that strains C64T and C62 represent a novel species belonging to a novel genus within the family Actinomycetaceae, for which the name Nanchangia anserum gen. nov., sp. nov. is proposed. The type strain is Nanchangia anserum C64T (=CGMCC 1.18410T=GDMCC 1.1969T=KCTC 49511T=KACC 22143T).
Assuntos
Actinomycetaceae/classificação , Gansos , Filogenia , Actinomycetaceae/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Fezes/microbiologia , Gansos/microbiologia , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/químicaRESUMO
Although the association of tuberculosis (TB) and the development of lung carcinoma (LC) has been acknowledged, the underlying mechanism remains not clarified. Since sustained and repeated local inflammation and tissue remodeling have been suggested to be responsible for the high incidence of developing CL from TB, we hypothesize that macrophages may play a critical role in the process. To prove it, we induced TB in mice by injection of virulent Mycobacterium tuberculosis (MTB). Then the mice were allotted into two groups. One group received weekly tail vein injection of 20 µg saporin-conjugated antibody against the pan-macrophage surface marker CD11b to eliminate macrophages, while the other group received injection of control IgG in the same frequency. Six months later, the development of LC was determined by histology. We found that the occurrence of LC in TB mice that received macrophage depletion was significantly lower than those in control TB mice without macrophage intervention. These data suggest that macrophages may promote the progression of TB into LC.
Assuntos
Inflamação/patologia , Neoplasias Pulmonares/patologia , Macrófagos/patologia , Tuberculose/patologia , Animais , Anticorpos/administração & dosagem , Modelos Animais de Doenças , Progressão da Doença , Humanos , Inflamação/complicações , Inflamação/microbiologia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/microbiologia , Macrófagos/microbiologia , Camundongos , Mycobacterium tuberculosis/patogenicidade , Tuberculose/complicações , Tuberculose/microbiologiaRESUMO
The development of a new generation of solid particle solar receivers (SPSRs) with high solar absorptivity (0.28-2.5 µm) and high infrared emissivity (1-22 µm) is crucial and has attracted much attention for the attainment of the goals of "peak carbon" and "carbon neutrality". To achieve the modulation of infrared emission and solar absorptivity, two types of medium- and high-entropy rare-earth hexaboride (ME/HEREB6) ceramics, (La0.25Sm0.25Ce0.25Eu0.25)B6 (MEREB6) and (La0.2Sm0.2Ce0.2Eu0.2Ba0.2)B6 (HEREB6), with severe lattice distortions were synthesized using a high-temperature solid-phase method. Compared to single-phase lanthanum hexaboride (LaB6), HEREB6 ceramics show an increase in solar absorptivity from 54.06% to 87.75% in the range of 0.28-2.5 µm and an increase in infrared emissivity from 76.19% to 89.96% in the 1-22 µm wavelength range. On the one hand, decreasing the free electron concentration and the plasma frequency reduces the reflection and ultimately increases the solar absorptivity. On the other hand, the lattice distortion induces changes in the B-B bond length, leading to significant changes in the Raman scattering spectrum, which affects the damping constant and ultimately increases the infrared emissivity. In conclusion, the multicomponent design can effectively improve the solar energy absorption and heat transfer capacity of ME/HEREB6, thus providing a new avenue for the development of solid particles.
RESUMO
Non-O157 Shiga toxin-producing Escherichia coli (STEC) is an important pathogen that can cause zoonotic diseases. To investigate the antimicrobial resistance of STEC in China, non-O157 STEC isolates, recovered from domestic animals and humans from 12 provinces, were analyzed using antimicrobial susceptibility testing and whole genome characterization. Out of the 298 isolates tested, 115 strains showed resistance to at least one antimicrobial and 85 strains showed multidrug resistance. The highest resistance rate was to tetracycline (32.6%), followed by nalidixic acid (25.2%) and chloramphenicol and azithromycin (both 18.8%). However, imipenem and meropenem were effective against all isolates. Antimicrobial resistance patterns varied among strains from different sources. Strains from pig, sheep, humans, and cattle showed resistance rates of 100.0%, 46.9%, 30.3%, and 6.3% to one or more antimicrobials, respectively. Forty-three genes related to 11 antimicrobial classes were identified among these strains. The colistin-resistance gene mcr was only carried by strains from pigs. A new fosfomycin-resistant gene, fosA7, was detected in strains from humans, cattle, and sheep. Whole genome phylogenetic analysis showed that strains from the four sources were genetically diverse and scattered throughout the phylogenetic tree; however, some strains from the same source had a tendency to cluster closely. These results provide a reference to monitor the emergence and spread of multidrug resistant STEC strains among animals and humans. Furthermore, with a better understanding of antimicrobial genotypes and phenotypes among the diverse STEC strains obtained, this study could guide the administration of antimicrobial drugs in STEC infections when necessary.
RESUMO
OBJECTIVE: To observe the relationship between the genetic polymorphism of P450-2E1 and the risk for antituberculosis drug-induced hepatotoxicity in a Chinese population. METHODS: Blood samples and clinical data were collected from 85 patients with antituberculosis drug-induced hepatotoxicity and 100 tuberculosis patients without hepatotoxicity as the control. DNA was extracted from the blood samples, and the frequencies of P450-2E1 RsaI genotypes were analyzed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The relationship between the polymorphisms of P450-2E1 RsaI and the antituberculosis drug-induced hepatotoxicity was analyzed. Predisposing factors for antituberculosis drug-induced hepatitis, such as gender, age, and polymorphism of P450-2E1 RsaI were evaluated by using logistic regression analysis. RESULTS: The frequencies of the 3 gene types P450-2E1 RsaI c1/c1, c1/c2, and c2/c2 were 75% (64/85), 20% (17/85) and 5% (4/85) respectively in patients with antituberculosis drug-induced hepatotoxicity, and 61% (61/100), 30% (30/100), and 9% (9/100) respectively in the controls. A statistical difference was found between the cases and the controls (chi(2) = 4.284, P < 0.05, OR = 2.016, 95%CI = 1.058 - 3.842). Logistic regression analysis showed that the polymorphism of P450-2E1 RsaI remained a significant independent risk factor for antituberculosis drug-induced hepatotoxicity after adjustment for age, gender and body mass index. CONCLUSION: Polymorphisms of P450-2E1 were found to be significantly associated with the risk of antituberculosis drug-induced hepatotoxicity, and the c1/c1 genotype was one of the risk factors.