Corrigendum: A dynamics association study of gut barrier and microbiota in hyperuricemia.

[This corrects the article DOI: 10.3389/fmicb.2023.1287468.].

A dynamics association study of gut barrier and microbiota in hyperuricemia.

Introduction: The intricate interplay between gut microbiota and hyperuricemia remains a subject of growing interest. However, existing studies only provided snapshots of the gut microbiome at single time points, the temporal dynamics of gut microbiota alterations during hyperuricemia progression and the intricate interplay between the gut barrier and microbiota remain underexplored. Our investigation revealed compelling insights into the dynamic changes in both gut microbiota and intestinal barrier function throughout the course of hyperuricemia. Methods: The hyperuricemia mice (HY) were given intragastric administration of adenine and potassium oxalate. Gut microbiota was analyzed by 16S rRNA sequencing at 3, 7, 14, and 21 days after the start of the modeling process. Intestinal permeability as well as LPS, TNF-α, and IL-1ß levels were measured at 3, 7, 14, and 21 days. Results: We discovered that shifts in microbial community composition occur prior to the onset of hyperuricemia, key bacterial Bacteroidaceae, Bacteroides, and Blautia exhibited reduced levels, potentially fueling microbial dysbiosis as the disease progresses. During the course of hyperuricemia, the dynamic fluctuations in both uric acid levels and intestinal barrier function was accompanied with the depletion of key beneficial bacteria, including Prevotellaceae, Muribaculum, Parabacteroides, Akkermansia, and Bacteroides, and coincided with an increase in pathogenic bacteria such as Oscillibacter and Ruminiclostridium. This microbial community shift likely contributed to elevated lipopolysaccharide (LPS) and pro-inflammatory cytokine levels, ultimately promoting metabolic inflammation. The decline of Burkholderiaceae and Parasutterella was inversely related to uric acid levels, Conversely, key families Ruminococcaceae, Family_XIII, genera Anaeroplasma exhibited positive correlations with uric acid levels. Akkermansiaceae and Bacteroidaceae demonstrating negative correlations, while LPS-containing microbiota such as Desulfovibrio and Enterorhabdus exhibited positive correlations with intestinal permeability. Conclusion: In summary, this study offers a dynamic perspective on the complex interplay between gut microbiota, uric acid levels, and intestinal barrier function during hyperuricemia progression. Our study suggested that Ruminiclostridium, Bacteroides, Akkermansiaceae, Bilophila, Burkholderiaceae and Parasutterella were the key bacteria that play vital rols in the progress of hyperuricemia and compromised intestinal barrier, which provide a potential avenue for therapeutic interventions in hyperuricemia.

A novel WDR60 variant contributes to a late diagnosis of Jeune asphyxiating thoracic dystrophy in a Chinese patient: A case report.

We report a Chinese patient with JATD presenting a mild skeletal phenotype and with renal insufficiency as the initial symptom of the disease. A novel homozygous c.2789C>T (p.S930L) variant in the WDR60 gene was identified. Our report will help to improve awareness and diagnosability for this disease.

The role and mechanisms of gut microbiota in diabetic nephropathy, diabetic retinopathy and cardiovascular diseases.

Type 2 diabetes mellitus (T2DM) and T2DM-related complications [such as retinopathy, nephropathy, and cardiovascular diseases (CVDs)] are the most prevalent metabolic diseases. Intriguingly, overwhelming findings have shown a strong association of the gut microbiome with the etiology of these diseases, including the role of aberrant gut bacterial metabolites, increased intestinal permeability, and pathogenic immune function affecting host metabolism. Thus, deciphering the specific microbiota, metabolites, and the related mechanisms to T2DM-related complications by combined analyses of metagenomics and metabolomics data can lead to an innovative strategy for the treatment of these diseases. Accordingly, this review highlights the advanced knowledge about the characteristics of the gut microbiota in T2DM-related complications and how it can be associated with the pathogenesis of these diseases. Also, recent studies providing a new perspective on microbiota-targeted therapies are included.

Double synonymous mutations in exon 9 of the Cullin3 gene restore exon inclusion by abolishing hnRNPs inhibition.

All mutations in exon 9 of the Cullin3 gene associated with pseudohypoaldosteronism type II (PHA II) contribute to exon skipping to different degrees, but the specific molecular mechanism of this aberrant splicing is still unclear. The aims of this study were to investigate the regulatory mechanism underlying two synonymous splicing events, c.1221A > G (p. Glu407Glu) and c.1236G > A (p. Leu412Leu), and to discover a therapeutic strategy for correcting this aberrant splicing by targeting potential regulatory sites. Through a series of RNA pulldown, silver staining, western blotting, small interfering RNA knockdown, in vitro overexpression and single or double site-directed mutagenesis experiments, we first explored the pathogenesis of exon 9 skipping caused by mutations in the CUL3 gene and verified that the main splicing regulators associated with the synonymous c.1221A > G and c.1236G > A mutations were heterogeneous nuclear ribonucleoproteins. In addition, we verified that introducing another synonymous mutation, c.1224A > G (A18G), significantly rescued the abnormal splicing caused by c.1221A > G and c.1236G > A, highlighting the therapeutic potential for the treatment of PHA II.

Change of intestinal microbiota in mice model of bronchopulmonary dysplasia.

Background: Gut microbiota has been proposed to be related to the pathogenesis of pulmonary diseases such as asthma and lung cancer, according to the gut-lung axis. However, little is known about the roles of gut microbiota in the pathogenesis of bronchopulmonary dysplasia (BPD). This study was designed to investigate the changes of gut microbiota in neonatal mice with BPD. Methods: BPD model was induced through exposure to high concentration of oxygen. Hematoxylin and eosin (H&E) staining was utilized to determine the modeling efficiency. Stool samples were collected from the distal colon for the sequencing of V3-V4 regions of 16S rRNA, in order to analyze the gut microbiota diversity. Results: Alpha diversity indicated that there were no statistical differences in the richness of gut microbiota between BPD model group and control group on day 7, 14 and 21. Beta diversity analysis showed that there were statistical differences in the gut microbiota on day 14 (R = 0.368, p = 0.021). Linear discriminant analysis effect size (LEfSe) showed that there were 22 markers with statistical differences on day 14 (p < 0.05), while those on day 7 and 21 were 3 and 4, respectively. Functional prediction analysis showed that the top three metabolic pathways were signal transduction (PFDR = 0.037), glycan biosynthesis and metabolism (PFDR = 0.032), and metabolism of terpenoids and polyketides (PFDR = 0.049). Conclusions: BPD mice showed disorder of gut microbiota, which may involve specific metabolic pathways in the early stage. With the progression of neonatal maturity, the differences of the gut microbiota between the two groups would gradually disappear.

Corrigendum: Artesunate Suppresses Choroidal Melanoma Vasculogenic Mimicry Formation and Angiogenesis via the Wnt/CaMKII Signaling Axis.

[This corrects the article DOI: 10.3389/fonc.2021.714646.].

Hyperuricemia induces lipid disturbances by upregulating the CXCL-13 pathway.

The molecular mechanism underlying hyperuricemia-induced lipid metabolism disorders is not clear. The purpose of the current study was to investigate the mechanism of lipid disturbances in a hyperuricemia mice model. RNA-Seq showed that differentially expressed genes (DEGs) in the fatty acid synthesis signaling pathway were mainly enriched and CXCL-13 was significantly enriched in protein-protein interaction networks. Western blotting, Q-PCR, and immunofluorescence results further showed that hyperuricemia upregulated CXCL-13 and disturbed lipid metabolism in vivo and in vitro. Furthermore, CXCL-13 alone also promoted the accumulation of lipid droplets and upregulated the expression of FAS and SREBP1, blocking AMPK signaling and activating the PKC and P38 signaling pathways. Silencing CXCL-13 reversed uric-acid-induced lipid droplet accumulation, which further downregulated FAS and SREBP1 expression, inhibited the p38 and PKC signaling, and activated AMPK signaling. In conclusion, hyperuricemia induces lipid metabolism disorders via the CXCL-13 pathway, making CXCL-13 a key regulatory factor linking hyperuricemia and lipid metabolism disorders. These results may provide novel insights for the treatment of hyperuricemia.NEW & NOTEWORTHY The underlying molecular mechanism of hyperuricemia-induced lipid metabolism disorders is still unclear. The study aimed to investigate the mechanism of lipid disturbance in hyperuricemia mice model. To our knowledge, we proposed for the first time that CXCL-13 may be a key regulator of hyperuricemia and lipid metabolism disorders. These results may provide new insights for the clinical treatment of hyperuricemia.

Artesunate Suppresses Choroidal Melanoma Vasculogenic Mimicry Formation and Angiogenesis via the Wnt/CaMKII Signaling Axis.

Angiogenesis and vasculogenic mimicry (VM) are considered to be the main processes to ensure tumor blood supply during the proliferation and metastasis of choroidal melanoma (CM). The traditional antimalarial drug artesunate (ART) has some potential anti-CM effects; however, the underlying mechanisms remain unclarified. Recent studies have shown that the Wnt5a/calmodulin-dependent kinase II (CaMKII) signaling pathway has a close correlation with angiogenesis and VM formation. This study demonstrated that ART eliminated VM formation by inhibiting the aforementioned signaling pathway in CM cells. The microvessel sprouting of the mouse aortic rings and the microvessel density of chicken chorioallantoic membrane (CAM) decreased significantly after ART treatment. VM formation assay and periodic acid schiff (PAS) staining revealed that ART inhibited VM formation in CM. Moreover, ART downregulated the expression levels of the angiogenesis-related proteins vascular endothelial growth factor receptor (VEGFR) 2, platelet-derived growth factor receptor (PDGFR) and vascular endothelial growth factor (VEGF) A, and VM-related proteins ephrin type-A receptor (EphA) 2 and vascular endothelial (VE)-cadherin. The expression of hypoxia-inducible factor (HIF)-1α, Wnt5a, and phosphorylated CaMKII was also downregulated after ART treatment. In addition, we further demonstrated that ART inhibited the proliferation, migration, and invasion of OCM-1 and C918 cells. Collectively, our results suggested that ART inhibited angiogenesis and VM formation of choroidal melanoma likely by regulating the Wnt5a/CaMKII signaling pathway. These findings further supported the feasibility of ART for cancer therapy.

Antinociceptive Effect of Magnolol in a Neuropathic Pain Model of Mouse.

BACKGROUND AND OBJECTIVE: Neuropathic pain remains a clinical challenge with limited effective treatments. Previous studies have found that magnolol (Mag), an ingredient existing in some herbs, showed neuroprotective effect. However, it remains unclear whether Mag can alleviate neuropathic pain. METHODS: Chronic constriction injury (CCI) is used as the neuropathic pain model. Mice were randomly divided into 5 groups: Sham, CCI, CCI + 5, 10, 30 mg/kg Mag groups. Thermal and mechanical paw withdrawal threshold were performed at baseline and on the 3rd, 5th, 7th, 14th days post-surgery. Lumbar spinal cord and blood samples were collected on the 14th day. Blood lipid profile, kidney and liver functions, as well as the activation of microglia were evaluated, along with the related signal pathway examined using multiple methods including immunohistochemistry, RT-PCR and Western blot. RESULTS: Mag alleviated thermal and mechanical hypersensitivity in CCI mice. CCI activated microglia and upregulated the expression of P2Y12, while Mag inhibited microglial activation, and downregulated the expression of P2Y12. Mag also blocked the activation of p38 mitogen-activated protein kinase (MAPK) and other pain-related cytokines such as IL-6, TNF-α and IL-1ß. CONCLUSION: The findings indicate that Mag has antinociceptive effect on neuropathic pain, probably mediated through P2Y12 receptors and p38 MAPK mediated pathways. With its relatively safe profile, Mag may be a potential therapeutic agent for neuropathic pain.

Effects of Holothurian Glycosaminoglycan on the Sensitivity of Lung Cancer to Chemotherapy.

Sea cucumber is a kind of food. Holothurian glycosaminoglycan (hGAG) is extracted from the body wall of the sea cucumber. Administration of hGAG and cisplatin (DDP) together to treat lung cancer was investigated. Lung adenocarcinoma A549 cells were cultured and divided into 4 groups: control group, hGAG 100 µg/mL group, DDP 3 µg/mL group, and hGAG 100 µg/mL + DDP 3 µg/mL group. Cell inhibition and apoptosis was evaluated by CCK8 and Hoechst33258 staining. Cell cycle was tested by Annexin V-FITC/PI (propidium iodide) double-staining and flow cytometry. The expression of mRNA and protein of Bcl-2, Bax, caspase-3, and survivin were detected by reverse transcriptase-polymerase chain reaction and Western blot, respectively. The results showed that hGAG combined with DDP enhanced the inhibitory effect of DDP on A549 lung cells through apoptosis pathway. The mechanism of apoptosis may be related to the reduction of Bcl-2 and survivin, as well as the ascension of Bax and caspase-3. hGAG could promote A549 cell cycle arrest in G1 and G2 phase and improve the DDP chemotherapy effects on A549 cells.

The study of effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives.

To investigate the effect and mechanism of 630-nm laser on human lung adenocarcinoma cell xenograft model in nude mice mediated by hematoporphyrin derivatives (HPD) and provide theoretical basis for clinical photodynamic therapy (PDT). Human lung adenocarcinoma cell xenograft model in nude mice was established and randomly divided into four groups: control group, pure photosensitizer group, pure irradiation group, and photodynamic treatment group. The tumor volume growth was compared, and the tumor growth inhibition rate was calculated. HE staining was used for routine pathological observation of tumor sections, and gross conditions of cells, interstitium, and blood vessels in several groups of tumor tissues were observed. TUNEL staining was used to observe and compare the apoptosis induced by photodynamic therapy. Real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the expression level of angiogenesis-related factors VEGF, HIF-1α and apoptosis-related factors Bax and Bcl-2 mRNA in the transplanted tumor tissues. Western blot was employed to detect the expression of angiogenesis-related proteins VEGF, HIF-1α and apoptosis-related proteins Bax, Caspase-3, and Bcl-2. Compared with the other three groups, the tumor growth inhibition rate of the photodynamic treatment group was significantly increased and the difference was statistically significant (P < 0.05). HE staining showed that the animal model of lung adenocarcinoma A549 was successfully established. TUNEL staining revealed that more apoptotic cells were found in the photodynamic treatment group, and the apoptosis index was calculated. Compared with the other three groups, the difference was statistically significant (P < 0.05). RT-PCR results showed that compared with the other three groups, the mRNA expressions of VEGF, HIF-1α, and Bcl-2 in the photodynamic treatment group decreased, while the expression of Bax mRNA increased(P < 0.05), and the differences were statistically significant. Western blot results showed that protein expressions of VEGF, HIF-1α, and Bcl-2 decreased in the photodynamic treatment group, while protein expression level of Bax and Caspase-3 increased (P < 0.05), indicating statistically significant differences. The 630-nm laser mediated by hematoporphyrin derivatives can significantly inhibit the growth of human lung adenocarcinoma xenograft tumor in nude mice, the mechanism of which is related to the inhibition of tumor angiogenesis by down-regulating VEGF and HIF-1α gene expression, and the promotion of tumor apoptosis by up-regulating Bax, Caspase-3, and down-regulating Bcl-2 gene expression.

3D culture enhances chemoresistance of ALL Jurkat cell line by increasing DDR1 expression.

Three dimensional (3D) culture has gradually become a research hotspot in the field of drug screening, stem cell research, and tissue engineering due to its more physiological-like morphology and function. In this study, we compared the differences of cell proliferation, population, protein expression and chemoresistance profiles between two dimensional (2D) and 3D culture of acute lymphoblastic leukemia (ALL) Jurkat cell line. Polycaprolactone (PCL) is used for 3D culture owing to its biochemical properties and compatibility. Culturing of ALL Jurkat cell line in collagen type I coated polycaprolactone scaffold for 168 h increased cell proliferation, attachment, as well as the drug resistance to cytarabine (Ara-C) and daunorubicin (DNR) without changing the original CD2+CD3+CD4+dimCD8-CD34-CD45+dim phenotype, compared to uncoated PCL scaffold and tissue culture plate systems. Molecularly, increased chemoresistance is associated with the upregulation of discoidin domain receptor 1 (DDR1) and transcription factor STAT3. Inhibition of DDR1 activity by DDR1-specific inhibitor DDR-IN-1 accelerated cell death in the presence of Ara-C, DNR or their combination. These results demonstrated that 3D culture enhances chemoresistance of ALL Jurkat cell line by increasing DDR1 expression. Importantly, the cell adhesion-mediated drug resistance induced by DDR1 in the scaffold was similar to the clinical situation, indicating the 3D culture of cancer cells recapitulate the in vivo tumor environment and this platform can be used as a promising pre-clinic drug-screen system.

Gingival mesenchymal stem cells attenuate pro-inflammatory macrophages stimulated with oxidized low-density lipoprotein and modulate lipid metabolism.

OBJECTIVE: To examine the effects of gingival mesenchymal stem cells (GMSCs) on inflammatory macrophages upon oxidized low-density lipoprotein (ox-LDL) stimulation and evaluate therapeutic potential of GMSCs on mouse model of periodontitis associated with hyperlipidemia. METHODS: in vitro, GMSCs were co-cultured with macrophages for 48 h in the absence or presence of M1 polarizing conditions and oxidized low-density lipoprotein in the transwell system. The supernatants were collected for ELISA. M1 and M2 markers of macrophages were analyzed by flow cytometry and PCR, and lipid accumulation was assessed by oil red O staining. in vivo, eighteen mice were divided into three groups (n = 6): Group A (periodontally healthy mice as control), Group B (periodontitis mice with hyperlipidemia), Group C (periodontitis mice with hyperlipidemia with the transplantation of GMSCs). The serum levels of cholesterol and inflammatory factors were measured by automatic analyzer. Bone regeneration was evaluated by Masson staining. RESULTS: When co-cultured with GMSCs, the M1 markers of Tumor Necrosis Factor (TNF) -α, Interleukin (IL) -6, Interleukin (IL) -1ß, CD86, and Human Leukocyte Antigen (HLA) -DR were significantly reduced. In contrast, M2 markers such as Interleukin(IL) -10 and CD206 were moderately increased. Similar results were obtained in the cell culture supernatants. In animal experiment, GMSCs suppressed the expression of sterol regulatory element binding transcription factor 1c (SREBP-1c) and elevated the levels of peroxisome proliferator-activated receptor alpha (PPARα) and peroxisome proliferator activator receptor- coactivator 1(PGC-1α) in the liver, attenuated cholesterol dysfunction via the downregulation of low-density lipoprotein (LDL) and total cholesterol (TC), and the upregulation of high-density lipoprotein (HDL), and decreased the levels of TNF-α and IL-6. Moreover, GMSC treatment improved bone regeneration. CONCLUSION: GMSCs inhibit the activation of M1 macrophages, regulate lipid metabolism and reduce inflammatory response, and promote bone regeneration in mouse model of periodontitis associated with hyperlipidemia.

N-Acetyl-Glucosamine Sensitizes Non-Small Cell Lung Cancer Cells to TRAIL-Induced Apoptosis by Activating Death Receptor 5.

BACKGROUND/AIMS: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a potential anti-cancer agent due to its selective toxicity. However, many human non-small cell lung cancer (NSCLC) cells are partially resistant to TRAIL, thereby limiting its clinical application. Therefore, there is a need for the development of novel adjuvant therapeutic agents to be used in combination with TRAIL. METHODS: In this study, the effect of N-acetyl-glucosamine (GlcNAc), a type of monosaccharide derived from chitosan, combined with TRAIL was evaluated in vitro and in vivo. Thirty NSCLC clinical samples were used to detect the expression of death receptor (DR) 4 and 5. After GlcNAc and TRAIL co-treatment, DR expression was determined by real-time PCR and western blotting. Cycloheximide was used to detect the protein half-life to further understand the correlation between GlcNAc and the metabolic rate of DR. Non-reducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to detect receptor clustering, and the localization of DR was visualized by immunofluorescence under a confocal microscope. Furthermore, a co-immunoprecipitation assay was performed to analyze the formation of death-inducing signaling complex (DISC). O-linked glycan expression levels were evaluated following DR5 overexpression and RNA interference mediated knockdown. RESULTS: We found that the clinical samples expressed higher levels of DR5 than DR4, and GlcNAc co-treatment improved the effect of TRAIL-induced apoptosis by activating DR5 accumulation and clustering, which in turn recruited the apoptosis-initiating protease caspase-8 to form DISC, and initiated apoptosis. Furthermore, GlcNAc promoted DR5 clustering by improving its O-glycosylation. CONCLUSION: These results uncovered the molecular mechanism by which GlcNAc sensitizes cancer cells to TRAIL-induced apoptosis, thereby highlighting a novel effective agent for TRAIL-mediated NSCLC-targeted therapy.

Upregulated microRNA-429 inhibits the migration of HCC cells by targeting TRAF6 through the NF-κB pathway.

Increasing evidence indicates that miR-429 is involved in tumor suppression in various human cancers. however, its role in hepatocellular carcinoma (HCC) remains unclear. In the present study, we found that miR-429 was significantly downregulated in HCC tissue samples and cell lines. Upregulation of miR-429 markedly suppressed proliferation and migration of HCC cells. Moreover, we identified TRAF6 as a direct target of miR-429. Downregulation of TRAF6 partially attenuated the oncogenic effect of anti­miR-429 on HCC cells. Ectopic expression of miR-429 in HCC cells inhibited TCF-4 activity as well as nuclear accumulation of P65 and expression of the NF-κB targets c-Myc and phosphorylation of TAK1. In a nude xenograft model, miR-429 upregulation significantly decreased HCC growth. In conclusion, by targeting TRAF6, miR-429 is downregulated in HCC and inhibits HCC cell proliferation and motility. Our data suggest that miR-429 may serve as a potential anticancer target for the treatment of HCC.

Downregulation of NPM expression by Her-2 reduces resistance of gastric cancer to oxaliplatin.

Nucleophosmin (NPM) and human epidermal growth factor receptor-2 (Her-2) are abnormally expressed in various types of human malignant tumors, including gastric cancer, and have been closely associated with cancer chemoresistance. However, their interaction and roles in oxaliplatin resistance are not fully understood. Therefore, the present study aimed to elucidate the relationship between NPM and Her-2 in gastric cancer cell lines and clinical samples, and further investigated their role in the resistance of gastric cancer to oxaliplatin. Western blotting and reverse transcription-quantitative polymerase chain reaction confirmed that NPM and Her-2 expression were significantly upregulated in gastric cancer cells and clinical samples, and that their expression levels were strongly correlated. However, Her-2 expression was not affected by upregulation or downregulation of NPM expression in gastric cancer cells. Cell counting kit-8 assays demonstrated that the cell sensitivity to oxaliplatin decreased simultaneously with an increase in NPM expression. Furthermore, inhibition of Her-2 expression using trastuzumab significantly increased the sensitivity of the cells to oxaliplatin, which occurred simultaneously with the downregulation of NPM. These results indicated that inhibition of NPM, as a Her-2 downstream signal, may be a novel strategy to overcome oxaliplatin-resistant gastric cancer, and that trastuzumab and oxaliplatin may exhibit a synergistic antitumor effect in Her-2-positive gastric cancer cells.

Construction and identification of an RNA interference lentiviral vector targeting the mouse TNF-α gene.

The aim of this study was to construct RNA interference (RNAi) lentiviral vector particles targeting the mouse tumor necrosis factor-α (TNF-α) gene. Three types of small interfering RNA (siRNA) targeting the mouse TNF-α gene were designed, synthesized and transfected into RAW264.7 cells. Screening was performed to identify the siRNA sequence exhibiting the highest inhibition efficiency; based on this, recombinant lentiviral plasmids were constructed and co-transfected into 293T cells with packaging plasmids for the production of lentiviral particles. The screening results showed that the TNF-α mRNA expression levels of the three siRNA groups were significantly lower than those of the negative control group, with the highest inhibition rate in the siRNA2 group (83.09%). Similarly, the expression levels of TNF-α protein in the three siRNA groups were significantly lower than those of the negative control group, and the highest inhibition rate was found in the siRNA2 group (51.16%). The mRNA expression of interleukin (IL)-1ß and IL-6 showed no significant difference among the siRNA groups and the negative control. The recombinant lentiviral shuttle plasmid was constructed, and electrophoresis revealed the polymerase chain reaction product to be 343 bp, while that of the empty vector was 306 bp; DNA sequencing showed partial insertion. The virus titer was calculated to be 2×106 TU/µl. In conclusion, RNAi lentiviral vector particles targeting the mouse TNF-α gene were successfully obtained in the present study. This method may be used to produce lentiviral vector for the in vivo study of RNAi gene therapy targeting TNF-α.

Lentiviral vector-mediated doxycycline-inducible USP39 shRNA or cDNA expression in triple-negative breast cancer cells.

Triple-negative breast cancer (TNBC), characterized by distinct biological and clinicopathological features, has a poor prognosis due to lack of effective therapeutic targets. Our previous data revealed that high levels of USP39 were selectively present in TNBC samples compared with their normal breast tissue samples and USP39 was also expressed at different levels in cultured TNBC cells and normal breast cells. Yet, the underlying cellular and molecular mechanisms of USP39 remain unclear. In the present study, we describe a doxycycline (DOX)-regulated lentiviral vector system expressing shRNA or cDNA of the USP39 gene in the TNBC cell line MDA-MB-231. USP39 expression was knocked down by the miR-30-based inducible lentiviral short hairpin RNA (shRNA) delivery system or overexpressed by the inducible cDNA system. The inducible shRNA-mediated downregulation of USP39 expression markedly reduced the proliferation and colony-forming ability of MDA-MB-231 cells, while overexpression of USP39 by the inducible system did not promote cancer cell proliferation. The lentiviral vector-mediated Tet-on system demonstrated efficient and inducible knockdown of USP39 or overexpression of USP39 in TNBC cells, facilitating a wide variety of applications for gene knockdown and overexpression experiments in gene functional studies in vitro and in vivo.

In vitro toxicity evaluation of graphene oxide on human RPMI 8226 cells.

This study had investigated the possible toxicity of graphene oxide and its mechanisms on multiple myeloma cells (RPMI 8226 cells) using flow cytometry and a multifunctional microplate reader. RPMI 8226 cells were cultured with various concentrations of graphene oxide, then cell viability, malondialdehyde, glutathione and apoptosis were measured. We found that graphene oxide dose-dependently reduced the viability of human multiple myeloma RPMI 8226 cells. We also found that the intracellular levels of malondialdehyde increased, whereas the levels of glutathione decreased dose-dependently. There was no obvious change in the cell apoptosis rate compared with the control group. In summary, graphene oxide is dose-dependently cytotoxic to cultured RPMI 8226 cells, and its toxicity is closely associated with increased oxidative stress.