[Effect of Selinexor on Proliferation and Apoptosis of Acute Myeloid Leukemia Kasumi-1 Cells].

OBJECTIVE: To investigate the effects of selinexor, a inhibitor of nuclear export protein 1 (XPO1) on the proliferation inhibition and apoptosis of Kasumi-1 cells in acute myeloid leukemia (AML). METHODS: MTS method was used to detect the inhibitory effect of different concentrations of selinexor on the proliferation of Kasumi-1 cells at different time points. The apoptosis rate and cell cycle changes after treatment with different concentration of selinexor were detected by flow cytometry. RESULTS: Selinexor inhibited the growth of Kasumi-1 cells at different time points in a concentration-dependent manner (r 24 h=0.7592, r 48 h=0.9456, and r 72 h=0.9425). Selinexor inhibited Kasumi-1 cells growth in a time-dependent manner (r =0.9057 in 2.5 µmol/L group, r =0.9897 in 5 µmol/L group and r =0.9994 in 10 µmol/L group). Selinexor could induce apoptosis of Kasumi-1 cells in a dose-dependent manner (r =0.9732), and the apoptosis of Kasumi-1 cells was more obvious with the increase of drug concentration. The proportion of G0/G1 phase was significantly increased and the proportion of S phase was significantly decreased after the treatment of Kasumi-1 cells by selinexor. With the increase of drug concentration, the proportion of Kasumi-1 cells cycle arrest in G0/G1 phase was increased and the cell synthesis was decreased. CONCLUSION: Selinexor can promote the death of tumor cells by inhibiting Kasumi-1 cells proliferation, inducing apoptosis and blocking cell cycle.

Sandwich-type electrochemical immunosensing of CA125 by using nanoribbon-like Ti3C2Tx MXenes and toluidine blue/UIO-66-NH2.

CA125 (carbohydrate antigen 125) is an important biomarker of ovarian cancer, so developing effective method for its detection is of great significance. In the present work, a novel sandwich-like electrochemical immunosensor (STEM) of CA125 was constructed by preparing nanoribbon-like Ti3C2Tx MXenes (Ti3C2TxNR) to immobilize primary antibody (PAb) of CA125 and UIO-66-NH2 MOFs structure to immobilize second antibody (SAb) and electroactive toluidine blue (Tb) probe. In this designed STEM assay, the as-prepared Ti3C2TxNR nanohybrid offers the advantages in large surface area and conductivity as carrier, and UIO-66-NH2 provided an ideal platform to accommodate SAb and a large number of Tb molecules as signal amplifier. In the presence of CA125, the peak currents of Tb from the formed STEM structure increase with the increase of CA125 level. After optimizing the related control conditions, a wide linear range (0.2-150.0 U mL-1) and a very low detection limit (0.05 U mL-1) of CA125 were achieved. It's thus expected the developed STEM strategy has important applications for the detection of CA125.

[Effect of Nucleolin on Lymphoma Proliferation by Regulating Thymidine Kinase 1].

OBJECTIVE: To investigate the mechanism of nucleolin (NCL) involved in lymphoma proliferation by regulating thymidine kinase 1 (TK1). METHODS: Twenty-three patients with diffuse large B-cell lymphoma (DLBCL) were selected and divided into initial treatment group (14 cases) and relapsed/refractory group (9 cases). Serum TK1 and C23 protein in peripheral blood mononuclear cells were detected. Cell models of CA46-NCL-KD (CA46-NCL-knockdown) and CA46-NCL-KNC (CA46-NCL-knockdown negative control) were established by lentivirus vector mediated transfection in Burkitt lymphoma cell line CA46. The half maximal inhibitory concentration (IC50) of CA46-NCL-KD, CA46-NCL-KNC, and CA46 to adriamycin were detected by cell proliferation assay (MTS). The expression of NCL mRNA and protein in CA46-NCL-KD and CA46-NCL-KNC cells were dectected by Q-PCR and Western blot, respectively. The cell cycle of CA46-NCL-KD, CA46-NCL-KNC, and CA46 cells were detected by flow cytometry. The expression of TK1 protein in CA46-NCL-KD and CA46-NCL-KNC cells was detected by an enhanced chemiluminescence (ECL) dot blot assay. RESULTS: The level of serum TK1 in the initial treatment group was 0.43(0-30-1.01) pmol/L, which was lower than 10.56(2.19-14.99) pmol/L in the relapsed/refractory group (P<0-01), and the relative expression level of NCL protein in peripheral blood was also significantly lower. The IC50 of CA46-C23-KD cells to adriamycin was (0.147±0.02) µg/ml, which was significantly lower than (0.301±0.04) µg/ml of CA46-C23-KNC cells and (0.338±0.05) µg/ml of CA46 cells (P<0.05). Compared with CA46-NCL-KNC cells, the expression of NCL mRNA and protein, TK1 protein decreased in CA46-NCL-KD cells, and the proportion of S phase and G2/M phase also decreased, while G0/G1 phase increased in cell cycle. CONCLUSION: The increased expression of NCL in DLBCL and CA46 cells indicates low sensitivity to drug. NCL may participate in regulation of lymphoma proliferation by affecting TK1 expression, thereby affecting the drug sensitivity.

Effect of nucleolin on adriamycin resistance via the regulation of B-cell lymphoma 2 expression in Burkitt's lymphoma cells.

Nucleolin (NCL, C23) is an important nucleocytoplasmic multifunctional protein. Due to its multifaceted profile and high expression in cancer, NCL is considered to be a marker of drug resistance associated with chemotherapy. However, the biochemical mechanisms in which NCL suppresses drug sensitivity in several cancers have yet to be fully elucidated. This study aims to explore the effect of NCL on drug sensitivity and its potential mechanism in CA46 Burkitt's lymphoma (BL) cells. CA46 BL cells were transfected with lentiviruses carrying the NCL gene (CA46-NCL-overexpression, CA46-NCL-OE), or shRNA sequences that target the endogenous NCL gene (CA46-NCL-knockdown, CA46-NCL-KD). Adriamycin (ADM) IC50 levels for CA46-NCL-overexpressed (OE), CA46-NCL-OE control (OEC), CA46-NCL-knockdown (KD), and CA46-NCL-KD control (KDC) cells were 0.68 ± 0.06 µg/ml, 0.68 ± 0.06 µg/ml, 0.68 ± 0.06 µg/ml, and 0.30 ± 0.04 µg/ml, respectively. Apoptosis rates were significantly increased following NCL KD, whereas the opposite effect was noted in OE cells. A significant reduction of B-cell lymphoma 2 (Bcl-2) mRNA and protein levels in KD cells was observed, while OE cells displayed the opposite effect. The stability of Bcl-2 mRNA was influenced by NCL levels, the half-life of which was extended after NCL-OE, whereas it was reduced in KD cells. Finally, results of RNA-immunoprecipitation assays indicated that NCL could bind to Bcl-2 mRNA in CA46 cells. Taken together, these results suggested that NCL could mediate Bcl-2 expression and stability, and thus enhance ADM resistance in CA46 BL cells.

Integration of bioinformatics and experiments to identify TP53 as a potential target in Emodin inhibiting diffuse large B cell lymphoma.

Non-Hodgkin's Lymphoma (NHL) is a group of lymphoid malignancies with unsatisfactory treatment effect in some aggressive subtypes, including diffuse large B cell lymphoma (DLBCL). Emodin is an anthraquinone with potent anti-cancer activities. However, the molecular mechanism of Emodin repressing aggressive NHL remains to be revealed in detail. This study delineated the active mechanism of Emodin action in aggressive NHL by using bioinformatics analysis and in vitro assay. 4 Emodin's primary direct protein targets (DPT) were identified and the DPTs-associated proteins/genes were predicted. Those Emodin-related proteins/genes were subject to enrich Emodin-associated pathways, from which 3 significantly NHL-related signal pathways were refined identified. Advanced integrated analysis exhibited TP53 and PI3K as the significant molecule and pathway by which Emodin may function in NHL. To verify those bioinformatics findings, effects of Emodin and E35, a novel derivative of emodin were investigated on DLBCL cell lines SU-DHL4. Emodin and E35 suppressed proliferation and induced apoptosis of SU-DHL4 cells in a time- and dose-dependent manner. Emodin and E35 declined TP53 protein expression and decreased phosphorylation of PI3K/AKT protein in a dose-dependent manner. All of above showed that combined bioinformatics analysis with experiments offered a novel approach for outlining the mechanisms of Emodin action in DLBCL with convenience and integrity.

Novel and rapid osteoporosis model established in zebrafish using high iron stress.

Osteoporosis is a global public health concern and, it can result from numerous pathogenic mechanisms, many of which are closely related with age, nutritional disorders, endocrine imbalance, or adverse drug side effects presented by glucocorticoids, heparin, and anti-epileptics. Given its wide range etiologies, it is crucial to establish an animal model of osteoporosis for use in screening potential drugs quickly and effectively. Previous research has reported that an accumulation of elevated iron in the body is an independent risk factor for osteoporosis. As such, we sought to use both zebrafish larvae and adults to model an osteoporosis phenotype using high iron stress (FAC, ferric ammonium citrate). Skeletal staining results suggested that iron-overload caused a significant decrease in bone calcification as well as severe developmental cartilage defects. In addition, osteoblast and cartilage-specific mRNA expression levels were downregulated after exposure to a high-iron environment. Most importantly, we demonstrated in both larval and adult fish that high iron-induced osteogenic defects were significantly rescued using alendronate (AL), a drug known to be effective against to human osteoporosis. Even more, the repair effect of AL was achieved by facilitating osteoblast differentiation and targeting Bmp signaling. Taken together, our findings propose an rapid and effective osteoporosis model, which could be used widely for future osteoporosis drug screening.

The Relationship Between MMP-2 -1306C>T and MMP-9 -1562C>T Polymorphisms and the Risk and Prognosis of T-Cell Acute Lymphoblastic Leukemia in a Chinese Population: A Case-Control Study.

BACKGROUND: T-cell acute lymphoblastic leukemia (T-ALL) is a malignant hematological disease and is often accompanied by a variety of genetic abnormalities. Hence, our study aims to investigate the relationship between MMP-2 -1306C>T and MMP-9 -1562C>T polymorphisms and the risk and prognosis of T-ALL. METHODS: From April 2009 to February 2011, a total of 376 T-ALL patients were chosen as the case group. Meanwhile, 352 healthy people who passed routine health examinations were selected as the control group. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to detect the frequency of MMP-2 -1306C>T (rs243865) and MMP-9 -1562C>T (rs3918242) polymorphisms in the study subjects. The serum levels of MMP-2 and MMP-9 were detected using enzyme-linked immunosorbent assay (ELISA). A Kaplan-Meier analysis was employed to analyze the event-free survival (EFS) rates of the T-All patients with different MMP-2 and MMP-9 genotypes. A multivariate COX model was applied to analyze the relationship between MMP-2 and MMP-9 polymorphisms and the prognosis of T-ALL patients. A C-statistic and net reclassification index (NRI) was carried out to evaluate the predictive value of MMP-2 and MMP-9 gene polymorphisms using the Cox model. RESULTS: Compared to the control group, the genotypic frequency of MMP-2 -1306C>T (CT + TT) and MMP-9 -1562C>T (CT + TT) in the case group was significantly higher. The serum level of MMP-9 was markedly elevated in T-ALL patients with the CT + TT genotype compared to patients with the CC genotype. The results of the Kaplan-Meier analysis showed that the median EFS was lower in T-ALL patients with the CT + TT genotype of MMP-9 -1562C>T compared to patients with the CC genotype. The results of a multivariate analysis using the Cox proportional hazard model indicated that the MMP-9 -1562C>T polymorphism was associated with the prognosis of T-ALL patients. CONCLUSION: These results indicated that MMP-2 -1306C/T and MMP-9 -1562C/T polymorphisms might be associated with an increased risk of T-ALL. The MMP-9 -1562C>T polymorphism may also be related to the prognosis of T-ALL patients.

The Transcriptome Study of Subtype M2 Acute Myeloblastic Leukemia.

Our objective is to explore the tumor-specific mutated genes by transcriptome sequencing of patients with acute myeloblastic leukemia. 96 patients with subtype M2 acute myeloid leukemia (AML), admitted during January 2007 to January 2012, were selected. Bone marrow and peripheral blood samples from the patients after the first visit and the patients who were improved or alleviated, were subjected to high-throughput sequencing to compare the gene expression. The single nucleotide mutation related to subtype M2 AML was detected. Meanwhile, real-time fluorescent quantitation RT-PCR was used to detect the AML1/ETO fusion gene and its correlation with prognosis after treatment. Among 96 patients, AML1-ETO fusion gene was positive in 52 cases, the positive rate was 54.17 %. The complete relief (CR) rate of AML1-ETO fusion gene positive patients was 84.62 %, and the CR rate of AML1/ETO fusion gene negative patients was 77.27 %; the CR rate of AML1-ETO positive patients was higher than that of patients without the fusion gene, however there was no statistical difference. In the analysis of recurrent gene mutation in AML-M2 patients, IDH2, ASXL1, TET2, JAK1 and JAK2 gene expressions were not significantly different before treatment and after CR, however, IDHI, JAK3, ABL1 and BCR gene expressions were significantly different. In the study of transcriptome in AML-M2 patients, high-throughput sequencing could effectively detect the difference of the gene expression before treatment and after CR. Furthermore, positive expression of AML1-ETO fusion gene had effect on the prognosis of patients.

[Investigation on the mechanisms of p15INK4B gene demethylation by valproate in Molt-4 cells].

OBJECTIVE: To study the antitumour effects of sodium valproate (VPA) on the proliferation, differentiation and cell cycle of Molt-4 cell and to investigate its demethylation mechanisms. METHODS: After Molt-4 cells trated with VPA at different concentrations, cell viability and growth curve were assessed by MTT assay. Cell cycle changes were analyzed by flow cytometry. The expression level of p15, DNA methyltransferase 1 (DNMT-1), DNMT3A and 3B mRNA were detected by RT-PCR and the methylation level was detected by hn-MSPCR. RESULTS: VPA significantly inhibited the proliferation of Molt-4 cells. After 48 h culture with 5.0 mmol/L VPA, the percentages of Molt-4 cells in G(0)/G(1) phase was (66.87 ± 3.31)% and in S phase was (8.47 ± 2.56)%, while in control group, the cells in G(0)/G(1) phase increased and in S phase decreased significantly. The p15 gene in Molt-4 cells failed to express due to its hypermethylation. The expression level of p15 gene mRNA increased significantly after exposure to VPA for 48 h. As compared with control group, the expression of DNMT-1 was down-regulated in a dose-dependent manner. The expression level of DNMT3B decreased at 10.0 mmol/L concentration. CONCLUSION: VPA has a demethylation effect on p15 INK4B gene by inhibiting the DNMT-1 and DNMT3B gene activities to recover p15 gene activity, which arrests Molt-4 cell in G(0)/G(1) phase.