Proliferation Of U251 Cells Research Articles

Azetidin-2-one-based small molecules as dual hHDAC6/HDAC8 inhibitors: Investigation of their mechanism of action and impact of dual inhibition profile on cell viability

The search of new therapeutic tools for the treatment of cancer is being a challenge for medicinal chemists. Due to their role in different pathological conditions, histone deacetylase (HDAC) enzymes are considered valuable therapeutic targets. HDAC6 is a well-investigated HDAC-class IIb enzyme mainly characterized by a cytoplasmic localization; HDAC8 is an epigenetic eraser, unique HDAC-class I member that displays some aminoacidic similarity to HDAC6. New polypharmacological agents for cancer treatment, based on a dual hHDAC6/hHDAC8 inhibition profile were developed. The dual inhibitor design investigated the diphenyl-azetidin-2-one scaffold, typified in three different structural families, that, combined to a slender benzyl linker (6c, 6i, and 6j), displays nanomolar inhibition potency against hHDAC6 and hHDAC8 isoforms. Notably, their selective action was also corroborated by measuring their low inhibitory potency towards hHDAC1 and hHDAC10. Selectivity of these compounds was further demonstrated in human cell-based western blots experiments, by testing the acetylation of the non-histone substrates alpha-tubulin and SMC3. Furthermore, the compounds reduced the proliferation of colorectal HCT116 and leukemia U937 cells, after 48 h of treatment. The toxicity of the compounds was evaluated in rat perfused heart and in zebrafish embryos. In this latter model we also validated the efficacy of the dual hHDAC6/hHDAC8 inhibitors against their common target acetylated-alpha tubulin. Finally, the metabolic stability was verified in rat, mouse, and human liver microsomes.

Effect of Licochalcone-A Combined with Rab23 Gene on Proliferation of Glioma U251 Cells.

This research aimed to explore the effect of Licochalcone-A (LCA) combined with Rab23 gene on the proliferation, migration, and invasion of glioma U251 cells through the Wnt/β-catenin signaling pathway. The glioma U251 cell line was taken as the research object, and the Rab23 overexpression plasmid was constructed. According to the treatment method, U251 cells were rolled into blank control group (BC), Rab23 overexpression plasmid transfection group (Rab23), 25 μmol·L−1 LCA treatment group (LCA), and Rab23 overexpression plasmid transfection combined with 25 μmol·L−1 LCA treatment group (Rab23 + LCA). Subsequently, the ability of cell proliferation, migration, and invasion of each group was detected by methyl thiazolyl tetrazolium (MTT) assay, scratch healing test, and Transwell cell invasion test, respectively. Western blot was implemented to detect the expression differences of cell proliferation antigen Ki-67, apoptosis-related proteins Bcl-2 and Bax, and Wnt/β-catenin pathway-related proteins β-catenin, glycogen synthase kinase-3 (GSK3β), Axin2, and c-myc. The results showed the successful construction of Rab23 overexpression and stable transfection U251 cell line. After grouping and treatments, the cell proliferation, migration, and invasion ability of the Rab23 group, LCA group, and Rab23 + LCA group was substantially reduced relative to BC group (P < 0.05). In addition, the cell proliferation, migration, and invasion ability of Rab23 + LCA group decreased relatively more significantly. The expression levels of Ki-67, Bcl-2, β-catenin, and c-myc in the Rab23, LCA, and Rab23 + LCA groups were greatly lower versus those of BC group. Moreover, the protein expression levels of Bax, GSK3β, and Axin2 were considerably increased (P < 0.05), while the expression of protein in Rab23 + LCA group increased notably. These findings indicate that LCA combined with Rab23 gene can inhibit the proliferation, migration, and invasion of glioma U251 cells through the Wnt/β-catenin signaling and can promote cell apoptosis.

Sevoflurane inhibits the malignant phenotypes of glioma through regulating miR-146b-5p/NFIB axis.

Sevoflurane is a common used inhaled anesthetic that was reported to regulate the progression of multiple cancers. Here, we aimed to investigate the function and regulatory mechanism underlying sevoflurane in glioma cells. A172 and U251 cells were treated with different concentrations of sevoflurane. Colony formation, EdU satining and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), flow cytometry, and transwell assays were performed to evaluate cell proliferation, apoptosis, migration and invasion, respectively. Circ_VCAN, microRNA-146b-5p (miR-146b-5p) and nuclear factor I B (NFIB) expression levels were assessed by real-time quantitative PCR (RT-qPCR) or western blot. Bioinformatics analysis and dual-luciferase reporter assay were applied to evaluate the correlation between miR-146b-5p and circ_VCAN or NFIB. A xenograft glioma mice model was established to verify the effect of sevoflurane on tumor growth in vivo. Sevoflurane (Sev) inhibited proliferation, migration, invasion, and elevated apoptosis of A172 and U251 cells. Sevoflurane treatment inhibited the expression of circ_VCAN and NFIB, but elevated the expression of miR-146b-5p in glioma cells. Overexpression of circ_VCAN alleviated the inhibition effects of sevoflurane on the malignant phenotypes of glioma in vitro and in vivo. Besides, miR-146b-5p is a target of circ_VCAN and negatively regulated NFIB expression. Overexpression of miR-146b-5p partly reversed the effects of circ_VCAN in Sev-treated glioma cells. Furthermore, miR-146b-5p deletion enhanced glioma progression in sevoflurane treated glioma cells by targeting NFIB. Moreover, circ_VCAN could upregulate NFIB expression by sponging miR-146b-5p in Sev-treated glioma cells. Sevoflurane alleviated proliferation, migration and invasion, but enhanced apoptosis of glioma cells through regulating circ_VCAN/miR-146b-5p/NFIB axis.

Polymer-Stabilized Elemental Boron Nanoparticles for Boron Neutron Capture Therapy: Initial Irradiation Experiments.

Sufficient boron-10 isotope (10B) accumulation by tumor cells is one of the main requirements for successful boron neutron capture therapy (BNCT). The inability of the clinically registered 10B-containing borophenylalanine (BPA) to maintain a high boron tumor concentration during neutron irradiation after a single injection has been partially solved by its continuous infusion; however, its lack of persistence has driven the development of new compounds that overcome the imperfections of BPA. We propose using elemental boron nanoparticles (eBNPs) synthesized by cascade ultrasonic dispersion and destruction of elemental boron microparticles and stabilized with hydroxyethylcellulose (HEC) as a core component of a novel boron drug for BNCT. These HEC particles are stable in aqueous media and show no apparent influence on U251, U87, and T98G human glioma cell proliferation without neutron beam irradiation. In BNCT experiments, cells incubated with eBNPs or BPA at an equivalent concentration of 40 µg 10B/mL for 24 h or control cells without boron were irradiated at an accelerator-based neutron source with a total fluence of thermal and epithermal neutrons of 2.685, 5.370, or 8.055 × 1012/cm2. The eBNPs significantly reduced colony-forming capacity in all studied cells during BNCT compared to BPA, verified by cell-survival curves fit to the linear-quadratic model and calculated radiobiological parameters, though the effect of both compounds differed depending on the cell line. The results of our study warrant further tumor targeting-oriented modifications of synthesized nanoparticles and subsequent in vivo BNCT experiments.

The effect of HOXC10 gene on biological behaviors of glioma cells and mechanism in tumor microenvironment

Objective: To study the effects of Homeobox C10 (HOXC10) on biological characteristics such as migration, invasion and proliferation of glioma cancer cells and to explore the role of HOXC10 gene in glioma microenvironment. Methods: The expression level of HOXC10 in high grade glioma (glioblastoma) and low grade glioma and its effect on patient survival were analyzed by using The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) database. Hoxc10-siRNA-1, HOXC10-siRNA-2 and siRNA negative control (NC) were transfected into U251 cells according to the operation instructions of HOXC10-siRNA transfection. 100 ng/ mL recombinant protein chemokine ligand 2 (reCCL2) was added into the transfection group, and was labeled as HOXC10-siRNA-1+ reCCL2 and HOXC10-siRNA-2+ reCCL2 groups. The expressions of HOXC10 mRNA and target protein in each group was detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) and western blot. The proliferation ability of cells in each group was detected by cell counting kit 8 (CCK8) method. The migration ability of cells was detected by Transwell assay and Nick assay, and cell apoptosis was detected by flow cytometry. The expression of chemokines in each group was detected by multiple factors. Co-incubation assays were performed to determine the role of HOXC10 and chemokine ligand 2 (CCL2) in recruiting and polarizing tumor-associated macrophages (M2-type macrophages). Results: The median expression level of HOXC10 in high grade gliomas was 8.51, higher than 1.00 in low grade gliomas (P<0.001) in TCGA database. The median expression level of HOXC10 in high grade gliomas was 0.83, higher than 0.00 in low grade gliomas (P=0.002) in CGGA database. The 5-year survival rate of patients with high HOXC10 expression in TCGA database was 28.2%, lower than 78.7% of those with low HOXC10 expression (P<0.001), and the 5-year survival rate of patients with high HOXC10 expression in CGGA database was 20.3%, lower than 58.0% of those with low HOXC10 expression (P<0.001). The numbers of cell migration in HOXC10-siRNA-1 group and HOXC10-siRNA-2 group were (45±3) and (69±4) respectively, lower than (159±3) in NC group (P<0.05). The cell mobility of HOXC10-siRNA-1 group and HOXC10-siRNA-2 group at 48 hours were (15±2)% and (28±4)% respectively, lower than (80±5)% of NC group (P<0.05). The expressions of vimentin in HOXC10-siRNA-1 group and HOXC10-siRNA-2 group were (141 740.00±34 024.56) and (94 655.00±5 687.97), N-cadherin were (76 810.00±14.14) and (94 254.00±701.45), β-catenin were (75 786.50±789.84) and (107 296.50±9 614.53), lower than (233 768.50±34 114.37), (237 154.50±24 715.50) and (192 449.50±24 178.10) of NC group (P<0.05). The A value of HOXC10-siRNA-1 group and HOXC10-siRNA-2 group were (0.44±0.05) and (0.32±0.02) at 96 hours, lower than 0.92±0.12 of NC group (P<0.05). The apoptosis rates of HOXC10-siRNA-1 group and HOXC10 siRNA-2 group were (10.23±1.24)% and (13.81±2.16)%, higher than (4.60±0.07)% of NC group (P<0.05). The expression levels of CCL2 in U251 cells in HOXC10-siRNA-1 and HOXC10-siRNA-2 groups were (271.63±44.27) and (371.66±50.21), lower than (933.93±29.84) in NC group (P<0.05). The expression levels of CCL5 (234.81±5.95 and 232.62±5.72), CXCL10 (544.13±48.14 and 500.87±15.65) and CXCL11 (215.75±15.30 and 176.18±16.49) in HOXC10-siRNA-1 and HOXC10-siRNA-2 groups were higher than those in NC group (9.98±0.71, 470.54±18.84 and 13.55±0.73, respectively, P<0.05). The recruited numbers of CD14(+) THP1 in HOXC10-siRNA-1 and HOXC10-siRNA-2 groups were (159.33±1.15) and (170.67±1.15), respectively, lower than (360.00±7.81) in NC group (P<0.05), while addition of reCCL2 promoted the recruitment of CD14(+) THP1 cells (287.00±3.61 and 280.67±2.31 in HOXC10-siRNA-1+ reCCL2 group and HOXC10-siRNA-2+ reCCL2 group, respectively, P<0.05). The expressions level of M2-type macrophage-related gene TGF-β in HOXC10-siRNA-1 group and HOXC10-siRNA-2 group were (0.30±0.02) and (0.28±0.02), respectively, lower than (1.06±0.10) in NC group (P<0.05). The expressions level of M1-related gene NOS2 in HOXC10-siRNA-1 and HOXC10-siRNA-2 were (11 413.95±1 911.85) and (5 894.00±945.21), respectively, higher than (13.39±4.32) in NC group (P<0.05). Conclusions: The expression of HOXC10 in glioma is high and positively correlated with the poor prognosis of glioma patients. Knockdown of HOXC10 can inhibit the proliferation, migration and metastasis of human glioma U251 cells. HOXC10 may play an immunosuppressive role in glioma microenvironment by promoting the expression of CCL2 and recruiting and polarizing tumor-associated macrophages (M2 macrophages).

In Silico Analysis Identifies Upregulated lncRNA DLGAP1-AS1 Which Is Correlated to Poor Prognosis and Promotes Cell Proliferation in Glioblastoma.

Long noncoding RNAs have been reported to regulate the tumorigenesis, growth, and metastasis of glioblastomas. In this study, we identified 1623 differently expressed mRNAs and 38 lncRNAs utilizing the CGGA and TCGA databases. Among these mRNAs and lncRNAs, we focused on DLGAP1-AS1 in this study. The results demonstrated that DLGAP1-AS1 was higher in WHO IV glioma than in WHO II and WHO III gliomas, higher in WHO III glioma than in WHO II glioma samples, higher in IDH1 wildtype glioma than in IDH1-mutant glioma samples, and higher in 1p/19q noncodeletion glioma than in 1p/19q codeletion glioma samples. Moreover, we observed that higher expression levels of DLGAP1-AS1 were correlated to shorter OS time in both low-grade and high-grade gliomas. Next, we evaluated the function of DLGAP1-AS1 in GBM using in vivo experiments. The data revealed that DLGAP1-AS1 knockdown greatly hindered U87 cell and U251 cell proliferation. Using coexpression network analysis, we identified that ATG4A was a potential downstream target of DLGAP1-AS1. The further analysis showed that ATG4B was significantly upregulated and correlated to shorter OS time in gliomas using both the CGGA and TCGA databases. Finally, we showed that ablated ATG4B greatly hindered GBM cell proliferation. Our conclusion suggested that DLGAP1-AS1 may be a potential prognosis biomarker and facilitated the occurrence and development of glioma via ATG4A in GBM.

Arene Ru(II) Complexes with Difluorinated Ligands Act as Potential Inducers of S-Phase Arrest via the Stabilization of c-myc G-Quadruplex DNA.

Here, a series of half-sandwich arene Ru(II) complexes with difluorinated ligands [Ru(η6-arene)(L)Cl] (L1 = 2-(2,3-difluorophenyl)imidazole[4,5f][1,10]-phenanthroline; L2 = 2-(2,4-difluorophenyl)imidazole[4,5f][1,10]-phenanthroline; arene = benzene, toluene, and p-cymene) were synthesized and characterized. Molecular docking analysis showed that these complexes bind to c-myc G-quadruplex DNA through either groove binding or π–π stacking, and the relative difluorinated site in the main ligand plays a role in regulating the binding mode. The binding behavior of these complexes with c-myc G-quadruplex DNA was evaluated using ultraviolet–visible spectroscopy, fluorescence intercalator displacement assay, fluorescence resonance energy transfer melting assay, and polymerase chain reaction. The comprehensive analysis indicated that complex 1 exhibited a better affinity and stability in relation to c-myc G-quadruplex DNA with a DC50 of 6.6 μM and ΔTm values of 13.09 °C, than other molecules. Further activity evaluation results displayed that this class of complexes can also inhibit the growth of various tumor cells, especially complexes 3 and 6, which exhibited a better inhibitory effect against human U87 glioblastoma cells (51.61 and 23.75 μM) than other complexes, even superior to cisplatin (32.59 μM). Owing to a befitting lipophilicity associated with the high intake of drugs by tumor cells, complexes 3 and 6 had favorable lipid-water partition coefficients of −0.6615 and −0.8077, respectively. Moreover, it was found that complex 6 suppressed the proliferation of U87 cells mainly through an induced obvious S phase arrest and slight apoptosis, which may have resulted from the stabilization of c-myc G-quadruplex DNA to block the transcription and expression of c-myc. In brief, these types of arene Ru(II) complexes with difluorinated ligands can be developed as potential inducers of S-phase arrest and apoptosis through the binding and stabilization of c-myc G-quadruplex DNA, and could be used in clinical applications in the future.

Exploring the mechanism of cordycepin combined with doxorubicin in treating glioblastoma based on network pharmacology and biological verification.

BackgroundGlioblastoma is the most common and fatal primary malignant tumor in the central nervous system, and the prognosis is poor. Currently, there are no effective treatments for glioblastoma. Cordycepin is a natural active substance with significant anticancer activity and doxorubicin is a broad-spectrum anticancer drug. Cordycepin administered with doxorubicin is a potential drug combination for the treatment of glioblastoma. However, the mechanism of action for this drug combination has not yet been elucidated.Aim of the studyTo explore the complex mechanism of cordycepin combined with doxorubicin against glioblastoma using network pharmacology and biological verification.Materials and methodsWe used an MTT assay, colony formation assay, and scratch healing to detect the growth, proliferation, and migration of LN-229, U251 and T98G cells. Putative targets and the potential mechanism of action for the drug combination in glioblastoma were obtained through online databases, network construction, and enrichment analyses. We verified the expression of EMT-related genes and identified important therapeutic targets by western blot.ResultsIn this study, the combination of doxorubicin and cordycepin was found to significantly inhibit cell proliferation and migration and can induce apoptosis. These effects are better together than with either drug alone. The drug combination inhibited EMT by upregulating the expression of E-cadherin protein and downregulating the expression of N-cadherin, ZEB1, and Twist1 proteins. There were 71 potential targets for the drug combination in glioblastoma, and Kyoto Encyclopedia of Genes and Genome analysis suggested that the anticancer process may be mediated by proteoglycans in cancer, the tumor necrosis factor signaling pathway, microRNA in cancer, pathways in cancer, and other pathways. To study the molecular mechanism of anticancer activity, we detected the expression of target proteins with downregulated expression of NFKB1, MAPK8, MYC, and MMP-9 proteins and upregulated expression of cleaved caspase 3 that promoted the apoptosis of LN-229 cells.ConclusionsThis study shows that the drug combination of doxorubicin and cordycepin effectively inhibits the growth and proliferation of LN-229 cells through multiple targets and multiple pathways, and the combination inhibits cell invasion and migration by regulating the EMT switch of tumor cells. Our findings provide new ideas about, and a theoretical basis for, the treatment of glioblastoma.

Dual-sgRNA CRISPR/Cas9 knockout of PD-L1 in human U87 glioblastoma tumor cells inhibits proliferation, invasion, and tumor-associated macrophage polarization

Programmed death ligand 1 (PD-L1) plays a key role in glioblastoma multiforme (GBM) immunosuppression, vitality, proliferation, and migration, and is therefore a promising target for treating GBM. CRISPR/Cas9-mediated genomic editing can delete both cell surface and intracellular PD-L1. This systemic deliverable genomic PD-L1 deletion system can be used as an effective anti-GBM therapy by inhibiting tumor growth and migration, and overcoming immunosuppression. To target PD-L1 for CRISPR/Cas9 gene editing, we first identified two single guide RNA (sgRNA) sequences located on PD-L1 exon 3. The first sgRNA recognizes the forward strand of human PD-L1 near the beginning of exon 3 that allows editing by Cas9 at approximately base pair 82 (g82). The second sgRNA recognizes the forward strand of exon 3 that directs cutting at base pair 165 (g165). A homology-directed repair template (HDR) combined with the dual-sgRNAs was used to improve PD-L1 knockout specificity and efficiency. sgRNAs g82 and g165 were cloned into the multiplex CRISPR/Cas9 assembly system and co-transfected with the HDR template in human U87 GBM cells (g82/165 + HDR). T7E1 analysis suggests that the dual-sgRNA CRISPR/Cas9 strategy with a repair template was capable of editing the genomic level of PD-L1. This was further confirmed by examining PD-L1 protein levels by western blot and immunofluorescence assays. Western blot analysis showed that the dual-sgRNAs with the repair template caused a 64% reduction of PD-L1 protein levels in U87 cells, while immunostaining showed a significant reduction of intracellular PD-L1. PD-L1 deletion inhibited proliferation, growth, invasion and migration of U87 cells, indicating intracellular PD-L1 is necessary for tumor progression. Importantly, U87 cells treated with g82/165 + HDR polarized tumor-associated macrophages (TAM) toward an M1 phenotype, as indicated by an increase in TNF-α and a decrease in IL-4 secretions. This was further confirmed with flow cytometry that showed an increase in the M1 markers Ly6C + and CD80 +, and a decrease in the M2 marker CD206 + both in vitro and in vivo. Utilizing dual-sgRNAs and an HDR template with the CRISPR/Cas9 gene-editing system is a promising avenue for the treatment of GBM.

LncRNA UCA1 Promotes the Progression of AML by Upregulating the Expression of CXCR4 and CYP1B1 by Affecting the Stability of METTL14.

Objective Increasing numbers of studies have proved that m6A methylation plays crucial roles in different cancers. However, how lncRNA regulates m6A methylation and participates in acute myeloid leukemia (AML) remains unclear. Therefore, this study aims to explore the function and mechanism of UCA1 in AML by regulating m6A methylation. Methods qRT-PCR, western blot, and immunohistochemical staining were used to detect the expression of METTL14, CXCR4, and CYP1B1. qRT-PCR was used to detect the expression of UCA1. CCK8, flow cytometry, and transwell assays were used to detect the proliferation, apoptosis, migration, and invasion of HL60 and U937 cells, respectively. m6A methylation was detected by dot blot analysis. Tumor-bearing mice were established, and tumor weight and volume were analyzed. Immunofluorescence staining, co-localization, and RNA pull-down were used to confirm the reaction between UCA1 and METTL14. Results Overexpression of UCA1 promotes AML development in vitro. Furthermore, we found that METTL14-influenced m6A methylation could be affected by UCA1. UCA1 promoted AML development by regulating m6A methylation. Moreover, the expression of CYP1B1 and CXCR4 was affected by METTL14. In addition, UCA1 promoted AML development by affecting m6A methylation in vivo. Conclusion In the present study, we demonstrated that lncRNAUCA1 promotes the progression of AML by upregulating the expression of CXCR4 and CYP1B1 by affecting the stability of METTL14.

CMTM6 knockdown prevents glioma progression by inactivating the mTOR pathway.

BackgroundGliomas in the adult brain are complicated and aggressive with a poor prognosis. Gene therapy is a recent alternative glioma treatment. We sought to explore the mechanism of chemokine-like factor (CKLF) MARVEL transmembrane domain-containing 6 (CMTM6) in glioma.MethodsThe Cancer Genome Atlas database reports that CMTM6 is expressed in tumors and glioma tissue. CMTM6 expression in glioma tissues and cells was detected and its relationship with clinical pathology was analyzed. Short hairpin ribonucleic acid-CMTM6 lentivirus was transfected into U87 and U251 cells to evaluate malignant glioma cells. Using the biological website (https://string-db.org/cgi/input.pl?Sessionid) and reference retrieval, the pathway that interacted with CMTM6 and related to glioma was identified. The level of the mammalian target of rapamycin pathway-related proteins was detected. Functional rescue experiments were performed using the combination of mTOR activator MHY1485 and the knockdown CMTM6. The growth of xenograft tumors was observed and Ki67-positive expression was determined.ResultsCMTM6 upregulation in gliomas was associated with a poor prognosis. CMTM6 expression was notably higher in gliomas. After the knockdown of CMTM6, the proliferation, invasion, and migration of U87 and U251 cells were inhibited, and the apoptosis rate was increased. Knocking down CMTM6 inactivated the mTOR pathway. The activation of mTOR pathway reversed the inhibitory effects of CMTM6 knockdown on glioma cell behaviors. CMTM6 knockdown reduced tumor volume, body mass, and Ki67-positive expression.ConclusionsThe knockdown of CMTM6 inhibited the activation of mTOR pathway and prevented the malignant episodes of glioma cells.

Strengthening Anti-Glioblastoma Effect by Multi-Branched Dendrimers Design of a Scorpion Venom Tetrapeptide.

Glioblastoma is the most aggressive and invasive form of central nervous system tumors due to the complexity of the intracellular mechanisms and molecular alterations involved in its progression. Unfortunately, current therapies are unable to stop its neoplastic development. In this context, we previously identified and characterized AaTs-1, a tetrapeptide (IWKS) from Androctonus autralis scorpion venom, which displayed an anti-proliferative effect against U87 cells with an IC50 value of 0.57 mM. This peptide affects the MAPK pathway, enhancing the expression of p53 and altering the cytosolic calcium concentration balance, likely via FPRL-1 receptor modulation. In this work, we designed and synthesized new dendrimers multi-branched molecules based on the sequence of AaTs-1 and showed that the di-branched (AaTs-1-2B), tetra-branched (AaTs-1-4B) and octo-branched (AaTs-1-8B) dendrimers displayed 10- to 25-fold higher effects on the proliferation of U87 cells than AaTs-1. We also found that the effects of the newly designed molecules are mediated by the enhancement of the ERK1/2 and AKT phosphorylated forms and by the increase in p53 expression. Unlike AaTs-1, AaTs-1-8B and especially AaTs-1-4B affected the migration of the U87 cells. Thus, the multi-branched peptide synthesis strategy allowed us to make molecules more active than the linear peptide against the proliferation of U87 glioblastoma cells.

Propofol inhibits proliferation and migration of glioma cells by up-regulating lncRNA GAS5

Propofol has been documented to exhibit anti-tumor effects in cancers. However, the underlying mechanisms of its inhibition remain unclear. We conducted this study to investigate the effect of propofol on lncRNA GAS5 in glioma cells, and to probe the role of GAS5 in the anti-tumor effects of propofol. Human glioma cell line U251 were treated with propofol. Cell proliferation, migration, invasion, cell cycle and apoptosis were evaluated, and the expression of GAS5 was measured. After that, we knockdown the expression of GAS5 in U251 cells by using siRNA and treated them with propofol, detected above indicators again and measured the expression of GAS5-related proteins. We found that propofol significantly reduced U251 cells proliferation, migration and invasion, induced cell cycle arrest and apoptosis while promoted GAS5 expression. These affects could be attenuated when GAS5 was down-regulated. Moreover, propofol increases the expression of P21, decreases the expression of c-Myc and GSTM3 through elevating GAS5 expression. In total, the anti-tumor activity of propofol on glioma cells was verified in this study. One possible mechanism involved was preliminary revealed: propofol up-regulates the expression of GAS5, thus stimulating P21 pathway, blocking c-Myc and GSTM3 pathways.

4,5-Dimethoxycanthin-6-one is a novel LSD1 inhibitor that inhibits proliferation of glioblastoma cells and induces apoptosis and pyroptosis

BackgroundGlioblastoma is one of the most common fatal intracranial malignancies. Lysine-specific demethylase 1 (LSD1) reportedly has therapeutic effects on a variety of tumors. This study explored the therapeutic effect of LSD1 inhibition on glioblastoma cell lines and the possible underlying mechanisms.MethodsThe MTT assay was utilized to screen for the sensitivity of U87, U251 and T98G cells to 4, 5-dimethoxycarrageenin-6-one. qRT-PCR and western blot were used to measure the proliferation, apoptosis, and pyroptosis signaling pathway expression to observe the effect of LSD1 inhibition on U251 and T98G cells. Flow cytometry, immunofluorescence, immunohistochemistry, wound scratch, clone formation, and TUNEL assay were used to analyze the effects of 4, 5-dimethoxycanthin-6-one on glioblastoma cells. The effect of 4, 5-dimethoxycanthin-6-one was examined in vivo in BALB/c nude mice injected with U251 cells. HE staining was used to detect the histopathology of the tumor.ResultsLSD1 specifically catalyzes the demethylation of monomethylated and demethylated histone H3 lysine at position 4 (h3k4me1, h3k4me2, h3k4me3) and lysine at position 9 (h3k9me1). This regulated the transcriptional activity of proliferation, apoptosis, and pyroptosis signaling pathway genes. In vitro, the proliferation of glioblastoma cells was decreased in the 4, 5-dimethoxycanthin-6-one group. The expression of Caspase1 in glioblastoma cells treated with 4, 5-dimethoxycanthin-6-one increased, and the number of apoptotic cells increased. The tumor volume of mice injected with 4, 5-dimethoxycanthin-6-one decreased significantly.Conclusion4, 5-Dimethoxycanthin-6-one could act as a novel inhibitor of LSD1 to regulate glioblastoma, which could inhibit the proliferation of U251 and T98G cells and induce their apoptosis and pyroptosis. It is a potential drug for the treatment of glioblastoma.

MT2-MMP is differentially expressed in multiple myeloma cells and mediates their growth and progression

ObjectiveMembrane type-matrix metalloproteinases (MT-MMPs) are known as key regulators of cancer progression/metastasis. However, their roles in the growth and progression of multiple myeloma (MM) have not been yet elucidated. Methods and materialsThe expression of 6 MT-MMPs in MM, B cell lines, and normal peripheral blood (PB) cells were measured by RT-PCR, qRT-PCR, flow cytometry, western blotting, and immunocytochemistry. B lymphocytes, CD19−/CD138−, and CD19−/CD138+ cells, known as malignant plasma cells (MPC), were sorted from bone marrow (BM) aspirations of 10 MM patients, and MT2-MMP expression was examined in these cells using qRT-PCR, flow cytometry and immunohistochemistry, and western blotting. Moreover, the expression of MT2-MMP in BM biopsies from 13 normal individuals and 14 MM patients was analyzed by immunohistochemistry. MT2-MMP was also knocked down in U266 cells using siRNA technology and the adhesion, invasion, migration abilities, and cell proliferation were determined and compared with scrambled ones in both in vitro and in vivo studies. ResultsOur results showed that MT2-MMP expression is significantly higher in MM cell lines and MPC cells than B cell lines and other PB- or BM-derived cells. MT2-MMP is expressed in BM biopsies from all 14 patients with MM, and 67.85% ± 32.38 of BM cells were positive for MT2-MMP. In contrast, only 0.38 ± 0.76 of BM biopsies from normal individuals were positive for MT2-MMP. Importantly, MT2-MMP was expressed in all the patients' BM biopsies at the diagnosis, but not in the remission phase. MT2-MMP siRNA significantly decreased adhesion, invasion, migration, and 3D cell proliferation of U266 cells. Moreover, in the xenographic model, MT2-MMP siRNA prevented the growth and development of plasmacytoma. Taken together, these data demonstrate that MT2-MMP is strongly expressed in MM cells and plays important role in the growth and progression of these cells, suggesting that MT2-MMP is an appropriate biomarker in diagnosis and therapeutic interventions of MM.

Retraction Note to: shRNA-mediated EMMPRIN silencing inhibits human leukemic monocyte lymphoma U937 cell proliferation and increases chemosensitivity to adriamycin.

Retraction Note to: shRNA-mediated EMMPRIN silencing inhibits human leukemic monocyte lymphoma U937 cell proliferation and increases chemosensitivity to adriamycin.

Suppression mechanisms on proliferation of glioma U251 cells by FePt nanoparticles through intracellular oxidative stress

Suppression mechanisms on proliferation of glioma U251 cells by FePt nanoparticles through intracellular oxidative stress

Effect of lentinan on proliferation and apoptosis of human astrocytoma U251 cells.

Aim of the study is To investigate the effect of lentinan on proliferation and apoptosis of human astrocytoma U251 cells. Lentinan was dissolved in DMEM complete medium to form different concentrations (0, 25, 50, 100, 200, 400, 500, 600 µg/ml). CCK8 was used to detect the effect of lentinan with different concentrations on proliferation of human astrocytoma U251 cells, and the expression of Ki-67 was detected by immunofluorescence. In addition, the effect of different concentrations of lentinan on apoptosis of human astrocytoma U251 cells was detected by flow cytometry. Compared with the blank control group, 50 and 100 µg/ml lentinan significantly promoted proliferation of human astrocytoma U251 cells. When the concentration is more than 100 µg/ml, the cell activity gradually decreases, and the cell activity is the lowest when the concentration is 600 µg/ml. In addition, the low concentration lentinan (25, 50, and 100 µg/ml) had no significant effect on apoptosis of human astrocytoma U251 cells. However, lentinan above 200 µg/ml significantly promoted apoptosis of human astrocytoma U251 cells and had a concentration gradient effect, and the highest apoptosis rate was at 600 µg/ml. Lentinan can effectively inhibit proliferation and promote apoptosis of human astrocytoma U251 cells.

3BDO inhibits the proliferation, epithelial-mesenchymal transition (EMT), and stemness via suppressing survivin in human glioblastoma cells

Background: Glioblastoma (GBM) is a tumor of the central nervous system with an extremely poor prognosis. Stemness and EMT play important roles in GBM progression. 3-benzyl-5-((2-nitrophenoxy) methyl) dihydrofuran-2(3H)-one (3BDO), an autophagy inhibitor, has been reported to exert anti-cancer activities on lung carcinoma. However, the effects of 3BDO on GBM remain unknown. Therefore, the purpose of this study was to explore the effects of 3BDO on GBM and to investigate the underlying molecular mechanisms.Method: CCK-8 experiments and clone formation assays were conducted to determine the level of cell proliferation. Transwell assay was conducted to examine cell migration and invasion abilities. Western blotting and immunofluorescence staining were used to analyze protein expression levels. A xenograft mouse model was used to evaluate the effect of 3BDO in vivo.Results: We found that 3BDO inhibited U87 and U251 cell proliferation in a dose-dependent manner. Additionally, 3BDO decreased the degree of sphere formation and levels of stemness markers (sox2, nestin, and CD133) in GSCs. 3BDO also inhibited migration and invasion abilities and suppressed EMT markers (N-cadherin, vimentin, and snail) in GBM cells. Moreover, we found that 3BDO downregulated the expression of survivin in both GBM cells (U87, U251) and GSCs. Furthermore, overexpression of survivin decreased the therapeutic effect of 3BDO on EMT, invasion, migration, and proliferation of GBM cells, as well as decreased the stemness of GSCs. Finally, we demonstrated that 3BDO could inhibit tumor growth in a tumor xenograft mouse model constructed using U87 cells. Similar to the in vitro findings, 3BDO decreased the expression of survivin, EMT makers, and the degree of stemness in vivo.Conclusions: Our results demonstrate that 3BDO can repress GBM both in vitro and in vivo via downregulating survivin-mediated stemness and EMT.

EPO activates PI3K-IKKα-CDK1 signaling pathway to promote the proliferation of Glial Cells under hypoxia environment.

Erythropoietin (EPO), supports the function and survival of neurons through astrocytes and has a protective role in neonatal asphyxia brain injury; yet, its mechanism of action remains unclear. As a neuroprotective factor, EPO is also used in the treatment of various diseases, such as neurodegenerative diseases, Parkinson’s disease, traumatic brain injury, by decreasing inflammatory reaction, resisting apoptosis, and lowering oxidative stress. The aim of this study was to examine the effect and mechanism of EPO on promoting human brain glial cell proliferation under hypoxia in vitro. Under CoC12-induced hypoxia, after adding EPO, high-throughput sequencing was used to screen out meaningful up-regulated and significant differentially expressed genes PI3K, IKKα CDK1 related to proliferation, and make further verification by qPCR and western blotting. Under hypoxia, EPO promoted cell proliferation and the expression of PI3K while this effect was inhibited (along with a decrease of downstream genes IKKα and CDK1 decreased) after adding PI3K inhibitor to cell culture. EPO can promote cell proliferation and CDK1 expression, while after inhibiting CDK1 expression, the promotion of EPO on cell proliferation was eliminated. These data proved that EPO promotes the proliferation of U251 cells by activating the PI3K-IKKα-CDK1 signaling pathway under CoC12-induced hypoxia.