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1.
EMBO J ; 42(3): e111364, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36477743

RESUMEN

Early embryonic development depends on proper utilization and clearance of maternal transcriptomes. How these processes are spatiotemporally regulated remains unclear. Here we show that nuclear RNA-binding protein Rbm14 and maternal mRNAs co-phase separate into cytoplasmic condensates to facilitate vertebrate blastula-to-gastrula development. In zebrafish, Rbm14 condensates were highly abundant in blastomeres and markedly reduced after prominent activation of zygotic transcription. They concentrated at spindle poles by associating with centrosomal γ-tubulin puncta and displayed mainly asymmetric divisions with a global symmetry across embryonic midline in 8- and 16-cell embryos. Their formation was dose-dependently stimulated by m6 A, but repressed by m5 C modification of the maternal mRNA. Furthermore, deadenylase Parn co-phase separated with these condensates, and this was required for deadenylation of the mRNAs in early blastomeres. Depletion of Rbm14 impaired embryonic cell differentiations and full activations of the zygotic genome in both zebrafish and mouse and resulted in developmental arrest at the blastula stage. Our results suggest that cytoplasmic Rbm14 condensate formation regulates early embryogenesis by facilitating deadenylation, protection, and mitotic allocation of m6 A-modified maternal mRNAs, and by releasing the poly(A)-less transcripts upon regulated disassembly to allow their re-polyadenylation and translation or clearance.


Asunto(s)
ARN Mensajero Almacenado , Pez Cebra , Animales , Femenino , Ratones , Embarazo , Blastocisto/metabolismo , Blástula/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Mensajero Almacenado/genética , ARN Mensajero Almacenado/metabolismo
2.
J Comput Assist Tomogr ; 47(1): 24-30, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36055224

RESUMEN

PURPOSE: The aim of the study is to assess the clinical value of the combined computed tomography (CT)/ultrasound (US) guidance in microwave ablation (MWA) for hepatocellular carcinoma (HCC). METHODS: From July 16, 2016, to June 20, 2021, medical records of 150 HCC patients treated with MWA were retrospectively analyzed. Ninety-two patients with 115 liver tumors underwent MWA under combined CT/US guidance, and 58 patients with 73 liver tumors received MWA under CT guidance alone. The clinical efficacy of combined CT/US-guided MWA was analyzed. We compared the complications, procedure time, and CT scan times between the 2 groups. RESULTS: The total complete ablation rate and complete ablation rate of high-risk location tumors were significantly higher in the group treated with combined CT/US guidance ( P = 0.0471 and P = 0.0347, respectively), the imaging guidance modality (odds ratio, 0.303; 95% confidence interval [CI], 0.095-0.970; P = 0.044) was an independent factor for ablation efficacy. These 2 groups also had significant differences in the procedure time ( P = 0.0171), the incidence rate of pneumothorax ( P = 0.0209), abdominal pain ( P = 0.0196), nausea or vomiting ( P = 0.0026), and intraoperative CT scan times ( P < 0.001). The overall complication rates ( P = 0.4023) and recurrence rates ( P = 0.5063) between the 2 groups were not statistically significant. However, CT/US group has a better short-term progressive free survival (log-rank P = 0.103, Breslow P = 0.030). In multivariate analysis, guidance modality (hazard ratio, 0.586; 95% CI, 0.368-0.934; P = 0.025) and Barcelona Clinic Liver Cancer stage (hazard ratio, 2.933; 95% CI, 1.678-5.127; P < 0.001) were risk factor for progressive free survival. CONCLUSIONS: Percutaneous MWA under the combined CT/US guidance for HCC can improve clinical benefits.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Neoplasias Hepáticas/patología , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Carcinoma Hepatocelular/patología , Microondas/uso terapéutico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento , Ablación por Catéter/métodos
3.
Clin Immunol ; 237: 108989, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35358679

RESUMEN

Primary Sjögren's Disease (pSjD) is considered a B cell-mediated disease. Toll-like receptor 10 (TLR10) is highly expressed in human B cells, indicating that TLR10 probably plays a vital role in pSjD. We examined TLR10 expression in peripheral B subsets of pSjD patients and analyzed their association with disease activity. We observed that TLR10 expression in total, naïve, memory, and switched memory B cells was significantly increased in low-activity pSjD patients as compared with healthy controls and high-activity patients. TLR10 expression in the above mentioned B subsets (except naïve B) was negatively correlated with serum levels of anti-SSA antibody and BAFF, respectively. Moreover, a higher proportion of high-activity pSjD patients was observed in TLR10 low- than high-expressed patients. Our study concluded that TLR10 expression in CD19+ B and memory B was negatively correlated with pSjD disease activity, suggesting that TLR10 might take part in the progression of pSjD.


Asunto(s)
Linfocitos B , Síndrome de Sjögren , Receptor Toll-Like 10 , Antígenos CD19/metabolismo , Humanos , Recuento de Linfocitos , Síndrome de Sjögren/patología , Receptor Toll-Like 10/metabolismo
4.
J Cell Biochem ; 120(4): 5033-5041, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30506710

RESUMEN

OBJECTIVES: Hepatocarcinoma is one of the most lethal cancers, leading to a 5-year survival rate as low as 30% due to recurrence and metastasis. The treatment of liver cancer includes surgery and medication, of which, the former is more effective. However, surgical resection is applicable in less than 40% of patients. Therefore, it is imperative to find effective medication options for liver cancer therapy. METHODS: In this study, we found that two natural products, geraniol and lupeol, had antiproliferative and proapoptotic effects on the hepatocarcinoma cell lines SMMC7721 and HepG2. We also detected a lower expression level of Bcl-2 and upregulation of BAX and caspase in the presence of geraniol and lupeol. RESULTS: Furthermore, geraniol or lupeol also altered the phosphorylation level of extracellular signal-regulated protein kinase, P38, and c-Jun NH2-terminal kinases, suggesting involvement in mitogen-activated protein kinase signaling. CONCLUSIONS: This study provided direct evidence to support the effect of geraniol and lupeol in hepatocarcinoma cell growth and apoptosis, which indicated the potential application of these two natural products in anti-liver cancer therapy.


Asunto(s)
Monoterpenos Acíclicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/enzimología , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/enzimología , Neoplasias Hepáticas/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Triterpenos Pentacíclicos/farmacología , Carcinoma Hepatocelular/genética , Caspasas/genética , Caspasas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes Supresores de Tumor , Humanos , Neoplasias Hepáticas/genética , Oncogenes , Fosforilación/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
5.
J Cell Biochem ; 120(8): 12273-12279, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31001851

RESUMEN

SUBJECTS: The aim of this study was to research the antiapoptotic effect of astragaloside, the principal component of Astragalus membranaceus (Fisch) Bge, in human gingiva cells induced by lipopolysaccharide (LPS). METHODS: According to the treatment, human gingiva cells were divided into five groups, including (1) control group without drug treatment; (2) imitating group, treated with LPS (10 µg·mL-1 ) alone; (3) low group, treated with LPS and 50 µmol·L -1 astragaloside; (4) medium group, treated with LPS and 100 µmol·L -1 astragaloside; and (5) high group, treated with LPS and 150 µmol·L -1 astragaloside. Cell proliferation and apoptosis were investigated using MTT assay and flow cytometry, respectively. Apoptosis and mitogen-activated protein kinase associated proteins were determined using Western blot analysis. RESULTS: LPS significantly suppressed the proliferation of human gingiva cells, but astragaloside obviously attenuated this change with a dose-dependent manner. LPS significantly promoted the apoptosis of human gingiva cells, but astragaloside treatments significantly attenuated this change with a dose-dependent manner. In addition, LPS could significant upregulated the expression of P-p38, P-JNK, Bax, and caspase-3. CONCLUSION: Astragaloside preformed a promising antiapoptotic role in apoptosis of human gingiva cells induced by LPS. This finding might provide us with a novel therapeutic method in tooth protection.


Asunto(s)
Apoptosis/efectos de los fármacos , Encía/citología , Lipopolisacáridos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Saponinas/farmacología , Adolescente , Apoptosis/genética , Biomarcadores/metabolismo , Proliferación Celular/efectos de los fármacos , Humanos , Adulto Joven
7.
Cancer Cell Int ; 14(1): 10, 2014 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-24472145

RESUMEN

INTRODUCTION: Although advanced gastric cancer has many limitations and response rate is marginal in chemotherapy. Overexpression of human epidermal growth factor receptor 2(HER-2/neu) gene and its protein are associated with increased cell division and a high rate of tumor growth and have been reported in several malignancies. Especially, approximately 30% of breast cancer patients have overexpression of HER-2/neu protein and the overexpression metastasize faster, induces resistance of the chemotherapy and down-regulate function of estrogen receptor. Recombinant humanized anti-HER2 antibody (Herceptin) inhibits proliferation of HER-2/neu overexpressing tumor cells and the use of that in combination in metastatic breast cancer have increased cytotoxicity of chemotherapeutic agents. METHODS: We evaluated the expression of HER-2/neu protein in gastric cell lines by FACS and then comparing the cytotoxicity in chemotherapeutics (doxorubicin, cisplatin, paclitaxel, 5-FU) alone and in combination with Herceptin according to the expression of HER-2/neu protein by MTT assay. RESULTS: 1. NCI-N87 (88%) gastric cancer cell line and SK-BR-3 (89%) breast cancer cell line with strong positivity of HER-2/neu expression. YBC-2 (55%) and YBC-3 (48%) gastric cancer cell line with intermediated, weak positivity respectively. Negative control U-87 MG (6%) brain cancer cell line were showed low expression of HER-2/neu. 2. Cell growth was dose-dependently inhibited in HER-2/neu positive, control cell line SK-BR-3 by Herceptin treatment but not observed in HER-2/neu negative control cell line U-87 MG. Effective growth inhibition was not observed in gastric cancer cell lines with single treatment of Herceptin, all cell lines observed the dose-dependent growth inhibition to chemotherapeutic agents (doxorubicin, cisplatin, paclitaxel and 5-FU). 3. Combination of Herceptin with doxorubicin observed synergistic effects in all cancer cell lines except YBC-3, combination of Herceptin with cisplatin observed NCI-N87 and SK-BR-3 and combination of Herceptin with paclitaxel observed synergistic effects in YBC-2. Combination of Herceptin with 5-FU observed antagonistic effects in all cancer cell lines. CONCLUSIONS: According to HER-2/neu expression level, effect of anti-cancer agents was observed differently in combination of Herceptin with chemotherapeutic agents. This suggests that HER-2/neu expression level can be applied standard of combination drug selection in combination of Herceptin With chemotherapeutic agents in gastric cancer.

8.
J Exp Med ; 221(3)2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38284990

RESUMEN

Human lung adenosquamous cell carcinoma (LUAS), containing both adenomatous and squamous pathologies, exhibits strong cancer plasticity. We find that ALK rearrangement is detectable in 5.1-7.5% of human LUAS, and transgenic expression of EML4-ALK drives lung adenocarcinoma (LUAD) formation initially and squamous transition at late stage. We identify club cells as the main cell-of-origin for squamous transition. Through recapitulating lineage transition in organoid system, we identify JAK-STAT signaling, activated by EML4-ALK phase separation, significantly promotes squamous transition. Integrative study with scRNA-seq and immunostaining identify a plastic cell subpopulation in ALK-rearranged human LUAD showing squamous biomarker expression. Moreover, those relapsed ALK-rearranged LUAD show notable upregulation of squamous biomarkers. Consistently, mouse squamous tumors or LUAD with squamous signature display certain resistance to ALK inhibitor, which can be overcome by combined JAK1/2 inhibitor treatment. This study uncovers strong plasticity of ALK-rearranged tumors in orchestrating phenotypic transition and drug resistance and proposes a potentially effective therapeutic strategy.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Animales , Ratones , Neoplasias Pulmonares/genética , Pulmón , Proteínas Tirosina Quinasas Receptoras , Proteínas de Fusión Oncogénica/genética
9.
Front Oncol ; 13: 1015976, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36937414

RESUMEN

Background: Irinotecan-loaded drug-eluting beads transarterial chemoembolization (DEBIRI-TACE) is a safe and effective therapeutic option for unresectable colorectal liver metastases (CRLM). The evaluation of treatment response after DEBIRI-TACE is very important for assessing the patient's condition. At present, the Response Evaluation Criteria in Solid Tumors (RECIST) with the tumor size obtained by CT and/or MRI and PET Response Criteria in Solid Tumors (PERCIST) based on fluorodeoxyglucose-positron emission tomography/computed tomography (FDG PET/CT) are used for evaluating the response to therapy of solid tumors; however, their value in the assessment of treatment response after DEBIRI-TACE remains unclear. Case presentation: A 52-year-old male with unresectable simultaneous CRLM was treated in the Affiliated Hospital of Yanbian University with DEBIRI-TACE combined with systemic chemotherapy and targeted therapy. Carcinoembryonic antigen levels decreased by 82.50% after 27 days of treatment. At 6 weeks post-surgery, FDG-PET/CT showed that the maximum standardized uptake value (SUVmax) of intrahepatic lesions was reduced to 62.14%. Abdominal MRI revealed that the sum of target lesion diameters was less than 30% that at baseline. PERCIST indicated partial metabolic response, whereas RECIST suggested stable disease. Conclusion: FDG PET/CT-based PERCIST may be accurate in determining treatment response and evaluating patient prognosis after DEBIRI-TACE in unresectable CRLM.

10.
J Hepatocell Carcinoma ; 10: 1587-1593, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37791067

RESUMEN

Background: Advanced-stage hepatocellular carcinoma (HCC), especially huge HCC or portal vein tumour thrombus (PVTT), is difficult to treat, and the prognosis is poor. The advantages of hepatic artery infusion chemotherapy (HAIC) combined with targeted therapy and immunotherapy for this complex disease are gradually becoming apparent. However, HAIC still has some inevitable disadvantages, such as arterial perfusion therapy requiring a long time, which results in many patients having difficulty completing the procedure. Modified HAIC (mHAIC)-based oxaliplatin and S-1 is a new treatment option for huge HCC or PVTT that can reduce complications and improve patient compliance. We report two cases of huge HCC or PVTT that were successfully treated with mHAIC combined with lenvatinib and camrelizumab. The clinical presentations, treatment strategies, and outcomes of these cases are presented. Case Presentation: Case 1: A 52-year-old female was found to have a huge HCC with a size of 14×11 cm. She was treated with one cycle of mHAIC combined with transcatheter arterial chemoembolization (TACE), lenvatinib and camrelizumab and 3 cycles of mHAIC in combination with lenvatinib and camrelizumab. The patient's follow-up maintenance therapy with lenvatinib and camrelizumab has been evaluated for efficacy in achieving complete response (CR). Case 2: A 57-year-old man was diagnosed with advanced HCC in combination with PVTT. He achieved partial remission (PR) after four cycles of mHAIC combined with lenvatinib and camrelizumab. This was followed by treatment with lenvatinib and camrelizumab with an efficacy assessment for CR, and progression-free survival (PFS) was 7 months. Conclusion: For advanced HCC with a large mass or PVTT, mHAIC combined with lenvatinib and camrelizumab is a safe and effective treatment with good patient compliance.

11.
Front Immunol ; 14: 1071023, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36865549

RESUMEN

Exosomes are progressively being detected as an indicator for the diagnosis and prognosis of cancer in clinical settings. Many clinical trials have confirmed the impact of exosomes on tumor growth, particularly in anti-tumor immunity and immunosuppression of exosomes. Therefore, we developed a risk score based on genes found in glioblastoma-derived exosomes. In this study, we used the TCGA dataset as the training queue and GSE13041, GSE43378, GSE4412, and CGGA datasets as the external validation queue. Based on machine algorithms and bioinformatics methods, an exosome-generalized risk score was established. We found that the risk score could independently predict the prognosis of patients with glioma, and there were significant differences in the outcomes of patients in the high- and low-risk groups. Univariate and multivariate analyses showed that risk score is a valid predictive biomarker for gliomas. Two immunotherapy datasets, IMvigor210 and GSE78220, were obtained from previous studies. A high-risk score showed a significant association with multiple immunomodulators that could act on cancer immune evasion. The exosome-related risk score could predict the effectiveness of anti-PD-1 immunotherapy. Moreover, we compared the sensitivity of patients with high- and low-risk scores to various anti-cancer drugs and found that patients with high-risk scores had better responses to a variety of anti-cancer drugs. The risk-scoring model established in this study provides a useful tool to predict the total survival time of patients with glioma and guide immunotherapy.


Asunto(s)
Exosomas , Glioblastoma , Glioma , Humanos , Glioblastoma/genética , Pronóstico , Exosomas/genética , Biomarcadores
12.
Chin J Cancer ; 31(5): 233-40, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22429494

RESUMEN

Although gene therapy was regarded as a promising approach for glioma treatment, its therapeutic efficacy was often disappointing because of the lack of efficient drug delivery systems. Mesenchymal stem cells(MSCs) have been reported to have a tropism for brain tumors and thus could be used as delivery vehicles for glioma therapy. Therefore, in this study, we attempted to treat glioma by using MSCs as a vehicle for delivering replication-competent adenovirus. We firstly compared the infectivity of type 3, type 5, and type 35 fiber-modified adenoviruses in MSCs. We also determined suitable adenovirus titer in vitro and then used this titer to analyze the ability of MSCs to deliver replication-competent adenovirus into glioma in vivo. Our results indicated that type 35 fiber-modified adenovirus showed higher infectivity than did naked type 3 or type 5 fiber-modified adenovirus. MSCs carrying replication-competent adenovirus significantly inhibited tumor growth in vivo compared with other control groups. In conclusion, MSCs are an effective vehicle that can successfully transport replication-competent adenovirus into glioma, making it a potential therapeutic strategy for treating malignant glioma.


Asunto(s)
Adenoviridae , Neoplasias Encefálicas/terapia , Glioma/terapia , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas , Viroterapia Oncolítica , Animales , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Vectores Genéticos , Glioma/patología , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Distribución Aleatoria , Replicación Viral , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): o618, 2012 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-22412528

RESUMEN

In the title compound, C(23)H(46)N(6)O(2), the two hy-droxy groups are located on opposite sides of the triazine ring. One of the hy-droxy groups links with the triazine N atom via an intra-molecular O-H⋯N hydrogen bond. Inter-molecular O-H⋯N and N-H⋯O hydrogen bonding is observed in the crystal structure. π-π stacking is also observed between parallel triazine rings of adjacent mol-ecules, the centroid-centroid distance being 3.5944 (14) Å.

14.
Front Mol Biosci ; 9: 823911, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281270

RESUMEN

Breast cancer is the most common malignancy and the leading cause of cancer-related deaths in women. Recent studies have investigated the prognostic value of the tumor microenvironment (TME)-related genes in breast cancer. The purpose of this research is to identify the immune-associated prognostic signature for breast cancer evaluate the probability of their prognostic value and compare the current staging system. In this study, we comprehensively evaluated the infiltration patterns of TME in 1,077 breast cancer patients downloaded from TCGA by applying the ssGSEA method to the transcriptome of these patients. Thus, generated two groups of immune cell infiltration. Based on two groups of low infiltration and high infiltration immune cell groups, 983 common differentially expressed genes were found using the limma algorithm. In addition, studying potential mechanisms, the GSEA method was used to indicate some pathways with remarkable enrichment in two clusters of immune cell infiltration. Finally, the seven immune-associated hub genes with survival as prognostic signatures were identified by using univariate Cox, survival, and LASSO analyses and constructed a TME score. The prognostic value of the TME score was self-validated in the TCGA cohort and further validated in an external independent set from METABRIC and GEO database by time-dependent survival receiver operation. Univariate and multivariate analyses of clinicopathological characteristics indicated that the TME score was an independent prognostic factor. In conclusion, the proposed TME score model should be considered as a prognostic factor, similar to the current TNM stage, and the seven immune-related genes can be a valuable potential biomarker for breast cancer.

15.
Cell J ; 24(11): 657-664, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36377215

RESUMEN

OBJECTIVE: The aim of this study is to elucidate the role of PRDX1 in hepatocellular carcinoma using hepatoma cells. MATERIALS AND METHODS: In this experimental study, we elucidated role of PRDX1, using hepatoma cell lines. RESULTS: PRDX1 was upregulated in different types of cancers, including lung adenocarcinoma, breast cancer and liver cancer reported by several studies. nevertheless, mechanism of inducing liver cell death by PRDX1 remains largely unknown. Here, we showed that PRDX1 expression is enhanced in different cell lines. Here, we used western blot, quantitative real time polymerase chain reaction (qRT-PCR) and different biochemical assays to explore the role of PRDX1. We observed that overexpression of PRDX1 significantly enhanced proliferation of hepatoma cell lines, while knock-down of this gene showed significant inhibitory effects. We found that knock-down of PRDX1 activated cleaved caspase-3, caspase-9 proteins and Poly [ADP-ribose] polymerase 1 (PARP-1), which further executed apoptotic process, leading to cell death. We found that PRDX1 knock-down significantly produced mitochondrial fragmentation. We showed that silencing PRDX1 led to the loss of B-cell lymphoma 2 (Bcl-2) and activated Bcl-2-like protein 11 (Bim) which further induced Bax activation. Bax further released cytochrome c from mitochondria and induced apoptotic proteins, suggesting a significant role of PRDX1 knock-down in apoptosis. Finally, we showed that knock-down of PRDX1 significantly activated expression of Dynein-related protein 1 (Drp1), fission 1 (Fis1) and dynamin-2 (Dyn2) suggesting a crucial role of PRDX1 in mitochondrial fragmentation and apoptosis conditions. This study highlighted an important role of PRDX1 in regulating proliferation of hepatoma cells and thus future studies are required to validate its effect on hepatcoytes. CONCLUSION: We propose that future works on PRDX1 inhibitors may act as a therapeutic candidate for treatment of liver cancer.

16.
Structure ; 30(3): 386-395.e5, 2022 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-34793709

RESUMEN

Rab9 is mainly located on late endosomes and required for their intracellular transport to trans-Golgi network (TGN). The cytoplasmic dynein motor, together with its regulatory proteins Nde1/Ndel1 and Lis1, controls intracellular retrograde transport of membranous organelles along the microtubule network. How late endosomes are tethered to the microtubule-based motor dynein for their retrograde transport remains unclear. Here, we demonstrate that the guanosine triphosphate (GTP)-bound Rab9A/B specifically uses Nde1/Ndel1 as an effector to interact with the dynein motor complex. We determined the crystal structure of Rab9A-GTP in complex with the Rab9-binding region of Nde1. The functional roles of key residues involved in the Rab9A-Nde1 interaction are verified using biochemical and cell biology assays. Rab9A mutants unable to bind to Nde1 also failed to associate with dynein, Lis1, and dynactin. Therefore, Nde1 is a Rab9 effector that tethers Rab9-associated late endosomes to the dynein motor for their retrograde transport to the TGN.


Asunto(s)
Dineínas Citoplasmáticas , Dineínas , Dineínas Citoplasmáticas/metabolismo , Citoesqueleto/metabolismo , Complejo Dinactina/metabolismo , Dineínas/metabolismo , Endosomas/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas de Unión al GTP rab/metabolismo
18.
Front Microbiol ; 13: 924709, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36312931

RESUMEN

Legionnaires' disease (LD), caused by Legionella, including the most prevalent Legionella pneumophila, has been treated primarily with antibiotics. Environmental water and soil are the reservoirs for L. pneumophila. Studying antimicrobial susceptibility using a large number of isolates from various environmental sources and regions could provide an unbiased result. In the present study, antimicrobial susceptibility of 1464 environmental L. pneumophila isolates that were derived from various environmental water and soil sources of 12 cities in China to rifampin (RIF), erythromycin (ERY), clarithromycin (CLA), azithromycin (AZI), ciprofloxacin (CIP), moxifloxacin (MOX), levofloxacin (LEV), and doxycycline (DOX) was investigated, and minimum inhibitory concentration (MIC) data were obtained. We show that regarding macrolides, ERY was least active (MIC90 = 0.5 mg/L), while CLA was most active (MIC90 = 0.063 mg/L). A total of three fluoroquinolones have similar MICs on L. pneumophila. Among these antimicrobials, RIF was the most active agent, while DOX was the most inactive one. We observed different susceptibility profiles between serogroup 1 (sg1) and sg2-15 or between water and soil isolates from different regions. The ECOFFs were ERY and AZI (0.5 mg/L), RIF (0.002 mg/L), CIP, CLA and MOX (0.125 mg/L), LEV (0.063 mg/), and DOX (32 mg/L). Overall, two fluoroquinolone-resistant environmental isolates (0.14%) were first documented based on the wild-type MIC distribution. Not all azithromycin-resistant isolates (44/46, 95.65%) harbored the lpeAB efflux pump. The MICs of the ERY and CLA on the lpeAB + isolates were not elevated. These results suggested that the lpeAB efflux pump might be only responsible for AZI resistance, and undiscovered AZI-specific resistant mechanisms exist in L. pneumophila. Based on the big MIC data obtained in the present study, the same defense strategies, particularly against both CLA and RIF, may exist in L. pneumophila. The results determined in our study will guide further research on antimicrobial resistance mechanisms of L. pneumophila and could be used as a reference for setting clinical breakpoints and discovering antimicrobial-resistant isolates in the clinic, contributing to the antibiotic choice in the treatment of LD.

19.
Microbiol Spectr ; 10(3): e0114021, 2022 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-35438512

RESUMEN

The distribution of pathogenic Legionella in the environmental soil and water of China has not been documented yet. In this study, Legionella was detected in 129 of 575 water (22.43%) and 41 of 442 soil samples (9.28%) by culture. Twelve Legionella species were identified, of which 11 were disease-associated. Of the Legionella-positive samples, 109 of 129 (84.50%) water and 29 of 41 (70.73%) soil were positive for L. pneumophila, which accounted for about 75% of Legionella isolates in both water and soil, suggesting L. pneumophila was the most frequent species. Soil showed a higher diversity of Legionella spp. as compared with water (0.6279 versus 0.4493). In contrast, serogroup (sg) 1 was more prevalent among L. pneumophila isolates from water than from soil (26.66% versus 12.21%). Moreover, many disease-associated sequence types (STs) of L. pneumophila were found in China. Intragenic recombination was acting on L. pneumophila from both water and soil. Phylogeny, population structure, and molecular evolution analyses revealed a probable existence of L. pneumophila isolates with a special genetic background that is more adaptable to soil or water sources and a small proportion of genetic difference between water and soil isolates. The detection of viable, clinically relevant Legionella demonstrates soil as another source for harboring and dissemination of pathogenic Legionella bacteria in China. Future research should assess the implication in public health with the presence of Legionella in the soil and illustrate the genetic and pathogenicity difference of Legionella between water and soil, particularly the most prevalent L. pneumophila. IMPORTANCE Pathogenic Legionella spp. is the causative agent of Legionnaires' disease (LD), and L. pneumophila is the most common one. Most studies have focused on L. pneumophila from water and clinical samples. However, the soil is another important reservoir for this bacterium, and the distribution of Legionella spp. in water and soil sources has not been compared and documented in China yet. Discovering the distribution of Legionella spp. and L. pneumophila in the two environments may help a deep understanding of the pathogenesis and molecular evolution of the bacterium. Our research systematically uncovered the distributions of Legionella spp. in different regions and sources (e.g., water and soil) of China. Moreover, phylogeny, population structure, and molecular evolution study revealed the possible existence of L. pneumophila with a special genetic background that is more adaptable to soil or water sources, and genetic difference may exist.


Asunto(s)
Legionella pneumophila , Legionella , Enfermedad de los Legionarios , Humanos , Legionella/genética , Enfermedad de los Legionarios/epidemiología , Suelo , Agua , Microbiología del Agua
20.
Cell Death Discov ; 8(1): 82, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35210425

RESUMEN

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of neoplastic B lymphocytes with high levels of Wnt5a in the plasma. Currently, the cell source of Wnt5a remains controversial. The receptor of Wnt5a is ROR1, whose expression is associated with disease progression and resistance to venetoclax, a BCL-2 inhibitor approved for the treatment of CLL. In this study, we found that the levels of Wnt5a in the plasma of CLL patients were positively correlated with absolute monocyte counts, but not lymphocyte counts. We cultured monocyte-derived nurse-like cells (NLCs) from patients with CLL, and detected Wnt5a expressed in NLCs. Flow cytometry and transwell assays showed that the antibody neutralizing Wnt5a inhibited the enhanced survival and migration in CLL cells co-cultured with NLCs. Furthermore, we performed a drug screening with CLL cells cultured with or without NLCs with a library containing 133 FDA-approved oncology drugs by using high-throughput flow cytometry. We observed a significant resistance to venetoclax in CLL cells co-cultured with NLCs. Immunoblot revealed the activation of NF-κB with enhanced expression of MCL-1 and BCL-XL in CLL cells co-cultured with NLCs. Neutralizing Wnt5a or blocking NF-κB pathway significantly decreased the expression of MCL-1 and BCL-XL, which leads to enhanced sensitivity to venetoclax in CLL cells co-cultured with NLCs. In conclusion, our data showed that NLCs could be one of the sources of Wnt5a detected in patients with CLL, and Wnt5a-induced NF-κB activation in the CLL microenvironment results in resistance to venetoclax in CLL cells.

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