CUDC-101, an effective and multi-target inhibitor of epidermal growth factor receptor (EGFR), histone deacetylase (HDAC), and human epidermal growth factor receptor 2 (HER2), has been reported to inhibit many kinds of cancers, such as acute promyelocytic leukemia and non-Hodgkin's lymphoma. However, no studies have yet investigated whether CUDC-101 is effective against myeloma. Herein, we proved that CUDC-101 effectively inhibits the proliferation of multiple myeloma (MM) cell lines and induces cell apoptosis in a time- and dose-dependent manner. Moreover, CUDC-101 markedly blocked the signaling pathway of EGFR/phosphoinositide-3-kinase (PI3K) and HDAC, and regulated the cell cycle G2/M arrest. Moreover, we revealed through in vivo experiment that CUDC-101 is a potent anti-myeloma drug. Bortezomib is one of the important drugs in MM treatment, and we investigated whether CUDC-101 has a synergistic or additive effect with bortezomib. The results showed that this drug combination had a synergistic anti-myeloma effect by inducing G2/M phase blockade. Collectively, our findings revealed that CUDC-101 could act on its own or in conjunction with bortezomib, which provides insights into exploring new strategies for MM treatment.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis ; Bortezomib/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; ErbB Receptors/antagonists & inhibitors* ; G2 Phase Cell Cycle Checkpoints ; Histone Deacetylase Inhibitors/pharmacology* ; Histone Deacetylases/metabolism* ; M Cells ; Multiple Myeloma/drug therapy*

Objective: To explore the impacts of miR-18a overexpression or depression on the radiosensitivities of nasopharyngeal carcinoma cell line CNE1 and CNE2 and underlying mechanisms. Methods: CNE1 and CNE2 were transfected with miR-18a mimics, inhibitor and the corresponding control vectors. qRT-PCR and western blot were used to determine the ataxia telangiectasia mutated (ATM) expressions in CNE1 and CNE2. CNE1 and CNE2 with stably expressing miR-18a and miR-18a siRNA were constructed. Methyl thiazolyl tetrazolium (MTT) assay was used to detect the impacts of the miR-18a overexpression or depression combined with irradiation on the cell growth. Flow cytometry was used to detect the cell apoptosis and cell cycle. Colony formation assay was used to evaluate the raodiosensitivities of cells. Acridine orange (AO) staining and western blot were used respectively to test the autophagy and the expressions of related proteins. Independent samples t test was used to compare the mean value between groups by using SPSS 16.0. Results: ATM mRNA was decreased significantly in CNE1 and CNE2 cells transfected with 100 or 200 nmol/L miR-18a mimics for 48 hours (CNE1: RQ=0.174±0.139 and 0.003±0.001, t=9.939 and 19 470.783;CNE2: RQ=0.024±0.008 and 0.019±0.012, t=270.230 and 137.746, respectively, all P<0.001). ATM proteins were also decreased after transfected with 100 or 200 nmol/L miR-18a mimics for 72 hours. While in the cells transfected with 100 and 200 nmol/L miR-18a inhibitor for 48 hours, the expressions of ATM mRNA were upregulated significantly (CNE1: RQ=9.419±2.495 and 2.500±1.063, t=-4.427 and -41.241; CNE2: RQ=7.210±0.171 and 115.875±15.805, t=-62.789 and -12.589, all P<0.05), and the expressions of ATM proteins increased after transfected for 72 hours. The growth of cells with miR-18a overexpression plus 4 Gy irradiation were obviously inhibited compared to that of cells with the 4Gy irradiation alone; while the growth of miR-18a-inhibited cells increased compared to that of cells with 4 Gy irradiation alone (all P<0.05). CNE1 transfected with 100 nmol/L miR-18a mimics plus 4 Gy irradiation showed the higher apoptosis rate than the cells with 4 Gy irradiation alone ((22.9±2.1)% vs. (16.3±1.0)%, t=-4.870, P<0.01). Compared to the cells with 4 Gy irradiation alone, miR-18a-overexpressed cells plus 4 Gy irradiation decreased their percentages in G1 phases ((20.2±3.0)% vs. (29.8±4.4)%, t=3.119) and G2/M phases ((21.5±0.9)% vs. (33.4±3.1)%, t=6.410, P<0.05 for both), and increased their percentages in S phases ((56.7±4.9)% vs. (36.8±6.4)%, t=-4.246, P<0.05), and these cells possessed less colony number after exposure to different doses of irradiation, more autophagy-lysosome number, and more expressions of LC3 proteins (all P<0.05). There were no significant differences in the expressions of p62 expressions between different groups of cells. Conclusion: Overexpression of miR-18a can enhance the radiosensitivities of NPC cells by targeting ATM to abrogate G1/S, G2/M arrest and to induce autophagy and apoptosis.
Apoptosis ; Autophagy ; Cell Line, Tumor ; Cell Proliferation ; G2 Phase Cell Cycle Checkpoints ; Humans ; MicroRNAs/genetics* ; Nasopharyngeal Carcinoma/genetics* ; Nasopharyngeal Neoplasms/genetics* ; Radiation Tolerance

OBJECTIVETo investigate the inducing effect of down-regulation of MCL-1 by diallyl disulfide(DADS) on the G/M arrest of human leukemia K562 cells and its mechanisms.

METHODSCCK-8 was used to detect the effect of DADS on proliferation of K562 cells, flow cytometry was employed to observe the effect of cycle arrest by DADS and RNAi silencing MCL-1 gene in K562 cells. The expressions of MCL-1, PCNA and CDK1 in K562 cells treated with DADS were detected by Western blot. The amphigamy of MCL-1 with PCNA and CDK1 was detected by Coimmunoprecipitation.

RESULTSCCK-8 detection showed that the inhibition rates of K562 cells treated with 15, 30, 60, 120, 240 µmol/L DADS were 32.48%, 59.34%, 66.42%, 77.06%, 81.05% respectively (P<0.05). Flow cytometry analysis revealed that the perecentages of G/M cells were increased to 18.6% and 34.4%, 17.5% and 28.5%, respectively at 24 and 48 h after treating K562 cells with 60 and 120 µmol/L DADS (P<0.05). And the perecentage of G/M cells of silencing MCL-1 was significantly increased (P<0.05). Silencing effects of MCL-1+DADS on the cells were enhanced more significantly as compared with DADS or MCL-1 alone (P<0.05). Western blot exhibited that DADS could markedly downregulate the expression of MCL-1, PCNA and CDK1(P<0.05). Coimmunoprecipitation revealed that MCL-1 bound with PCNA and CDK1, then forming heterodimers, which were downregulated respectively more significantly than that in the control group after treating K562 cells with DADS for 8 h (P<0.05).

CONCLUSIONDADS can inhibit the K562 cell proliferation and induce them arrest G/M through downregulation of MCL-1, then decreasing the expression of PCNA and CDK1 in hunan leukemia K562 cells. Moreover, silencing MCL-1 can enhance the effect of DADS.

Allyl Compounds ; Apoptosis ; Cell Line, Tumor ; Disulfides ; Down-Regulation ; G2 Phase Cell Cycle Checkpoints ; Humans ; K562 Cells ; Leukemia ; M Phase Cell Cycle Checkpoints ; Myeloid Cell Leukemia Sequence 1 Protein

PURPOSE: We previously found that the histone methyltransferase suppressor of variegation, enhancer of zeste, trithorax and myeloid-nervy-deformed epidermal autoregulatory factor-1 domain-containing protein 3 (SMYD3) is a potential independent predictive factor or prognostic factor for overall survival in gastric cancer patients, but its roles seem to differ from those in other cancers. Therefore, in this study, the detailed functions of SMYD3 in cell proliferation and migration in gastric cancer were examined. MATERIALS AND METHODS: SMYD3 was overexpressed or suppressed by transfection with an expression plasmid or siRNA, and a wound healing migration assay and Transwell assay were performed to detect the migration and invasion ability of gastric cancer cells. Additionally, an MTT assay and clonogenic assay were performed to evaluate cell proliferation, and a cell cycle analysis was performed by propidium iodide staining. Furthermore, the expression of genes implicated in the ataxia telangiectasia mutated (ATM) pathway and proteins involved in cell cycle regulation were detected by polymerase chain reaction and western blot analyses. RESULTS: Compared with control cells, gastric cancer cells transfected with si-SMYD3 showed lower migration and invasion abilities (P<0.05), and the absence of SMYD3 halted cells in G2/M phase and activated the ATM pathway. Furthermore, the opposite patterns were observed when SMYD3 was elevated in normal gastric cells. CONCLUSIONS: To the best of our knowledge, this study provides the first evidence that the absence of SMYD3 could inhibit the migration, invasion, and proliferation of gastric cancer cells and halt cells in G2/M phase via the ATM-CHK2/p53-Cdc25C pathway. These findings indicated that SMYD3 plays crucial roles in the proliferation, migration, and invasion of gastric cancer cells and may be a useful therapeutic target in human gastric carcinomas.
Ataxia Telangiectasia ; Blotting, Western ; Cell Cycle ; Cell Proliferation ; G2 Phase Cell Cycle Checkpoints ; Histones ; Humans ; Plasmids ; Polymerase Chain Reaction ; Propidium ; RNA, Small Interfering ; Stomach Neoplasms* ; Transfection ; Wound Healing

OBJECTIVETo investigate the effects of ophiopogonin D on human breast cancer MCF-7 cells.

METHODSCell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and colony formation experiments. Cell cycle was measured with cell cycle flow cytometry and a living cell assay. Apoptosis and terminal deoxynucleoitidyl transferase-mediated dUTP nick end labeling assays were performed to detect the apoptosis of MCF-7 cells induced by ophiopogonin D. Finally, Western blotting was used to explore the mechanism.

RESULTSExposure of cells to ophiopogonin D resulted in marked decreases in viable cells and colony formation with a dose-dependent manner. Treatment of these cells with ophiopogonin D also resulted in cell cycle arrest at the G(2)/M phase, and increased apoptosis. Mechanistically, ophiopogonin D-induced G(2)/M cell cycle arrest was associated with down-regulation of cyclin B1. Furthermore, activation of caspase-8 and caspase-9 was involved in ophiopogonin D-induced apoptosis.

CONCLUSIONThe data suggested that ophiopogonin D inhibits MCF-7 cell growth via the induction of cell cycle arrest at the G(2)/M phase.

Apoptosis ; drug effects ; Cell Proliferation ; drug effects ; G2 Phase Cell Cycle Checkpoints ; drug effects ; Humans ; M Phase Cell Cycle Checkpoints ; drug effects ; MCF-7 Cells ; Saponins ; pharmacology ; Spirostans ; pharmacology

PURPOSE: Isocryptotanshinone (ICTS) is a natural bioactive product that is isolated from the roots of the widely used medical herb Salvia miltiorrhiza. However, few reports exist on the mechanisms underlying the therapeutic effects of ICTS. Here, we report that ICTS has anticancer activity and describe the mechanism underlying this effect. METHODS: The antiproliferative effect of ICTS was determined using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and clonogenic assays. The effect of ICTS on the cell cycle was measured using flow cytometry. Apoptosis was determined by Hoechst 33342 staining, DNA fragmentation assays, and Western blotting for apoptotic proteins. Finally, the effect of ICTS on mitogen-activated protein kinases (MAPKs) was determined by Western blotting. RESULTS: ICTS significantly inhibited proliferation of MCF-7 and MDA-MB-231 human breast cancer cells, HepG2 human liver cancer cells, and A549 human lung cancer cells in vitro. Among the tested cell lines, MCF-7 cells showed the highest sensitivity to ICTS. ICTS significantly inhibited colony formation by MCF-7 cells. Furthermore, exposure of MCF-7 cells to ICTS induced cell cycle arrest at the G1 phase and decreased mitochondrial membrane potential. Hoechst 33342 staining and Western blot analysis for apoptotic proteins suggested that ICTS induced apoptosis in MCF-7 cells. In addition, ICTS activated MAPK signaling in MCF-7 cells by inducing time- and concentration-dependent phosphorylation of JNK, ERK, and p38 MAPK. CONCLUSION: Our results suggest that ICTS inhibited MCF-7 cell proliferation by inducing apoptosis and activating MAPK signaling pathways.
Apoptosis* ; Blotting, Western ; Breast Neoplasms* ; Cell Cycle ; Cell Cycle Checkpoints ; Cell Line ; DNA Fragmentation ; Flow Cytometry ; G1 Phase ; Hep G2 Cells ; Humans ; Liver Neoplasms ; Lung Neoplasms ; MCF-7 Cells* ; Membrane Potential, Mitochondrial ; Mitogen-Activated Protein Kinases ; p38 Mitogen-Activated Protein Kinases ; Phosphorylation ; Salvia miltiorrhiza

OBJECTIVETo investigate the expression of long non-coding RNA-HOTAIR in prostate cancer cells and its effects on the growth and metastasis of the cells.

METHODSUsing quantitative reverse-transcription PCR (qRT-PCR), we determined the relative expression of HOTAIR in the normal human prostate epithelial cell line RWPE-I and prostate cancer cell lines PC-3 and DU145. We detected the effects of HOTAIR on the cell cycle and invasiveness of prostate cancer cells by RNA interference, flow cytometry, and Transwell mitration assay.

RESULTSThe expressions of HOTAIR in the PC3 and DU145 cells were increased 3.2 and 5.7 times, respectively, as compared with that in the normal RWPE-1 cells. After si-HOTAIR interference, the prostate cancer cells were arrested in the G2 phase and downregulated in the G1 phase. The invasive ability of the prostate cancer cells was evidently inhibited, with the inhibition rates of 32% and 44% of the PC3 cells and 43% and 34% of the DU145 cells for si-HOTAIR1 and si-HOTAIR2, respectively.

CONCLUSIONIncRNA HOTAIR is highly expressed in prostate cancer, which is associated with the growth and invasiveness of prostate cancer cells. HOTAIR is potentially a novel marker for the diagnosis and prognosis of prostate cancer.

Cell Cycle ; Cell Cycle Checkpoints ; Cell Division ; Cell Line, Tumor ; Cell Proliferation ; Down-Regulation ; G1 Phase ; G2 Phase ; Humans ; Male ; Neoplasm Invasiveness ; Prognosis ; Prostatic Neoplasms ; metabolism ; pathology ; RNA Interference ; RNA, Long Noncoding ; metabolism ; RNA, Untranslated ; metabolism

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and it has a poor prognosis and few therapeutic options. Radiotherapy is one of the most effective forms of cancer treatment, and P53 protein is one of the key molecules determining how a cell responds to radiotherapy. The aim of this study was to determine the therapeutic efficacy of iodine-131 in three human HCC cell lines. METHODS: Western blotting was used to measure P53 expression. The effects of radiotherapy with iodine-131 were assessed by using the clonogenic assay to evaluate cell survival. Flow cytometry was carried out to examine the effects of iodine-131 on cell death, oxidative stress, reduced intracellular glutathione expression, the mitochondrial membrane potential, and the cell cycle. RESULTS: The P53 protein was not expressed in Hep3B2.1-7 cells, was expressed at normal levels in HepG2 cells, and was overexpressed in HuH7 cells. P53 expression in the HuH7 and HepG2 cell lines increased after internal and external irradiation with iodine-131. Irradiation induced a decrease in cell survival and led to a decrease in cell viability in all of the cell lines studied, accompanied by cell death via late apoptosis/necrosis and necrosis. Irradiation with 131-iodine induced mostly cell-cycle arrest in the G0/G1 phase. CONCLUSIONS: These results suggest that P53 plays a key role in the radiotherapy response of HCC.
Apoptosis/*radiation effects ; Blotting, Western ; Carcinoma, Hepatocellular/metabolism/pathology/radiotherapy ; Cell Line, Tumor ; Cell Survival/drug effects ; G1 Phase Cell Cycle Checkpoints/radiation effects ; *Gamma Rays ; Glutathione/metabolism ; Hep G2 Cells ; Humans ; Iodine Radioisotopes/chemistry/pharmacology/therapeutic use ; Liver Neoplasms/metabolism/pathology/radiotherapy ; Phosphorylation ; Reactive Oxygen Species/metabolism ; Tumor Suppressor Protein p53/*metabolism

This study was to examine the mechanism of oleanolic acid (OA) induces G2/M phase arrest and apoptosis in human hepatocellular carcinoma Bel-7402 cells. MTT and trypan blue exclusion test assay were adopted to detect the proliferate status of cells treated with OA. We assayed the cell cycle by flow cytometry using PI staining. Apoptosis was determined by Annexin V-FITC staining and PI labeling. The expressions of cycle related proteins and apoptotic related proteins were determined by Western blot analysis. OA strongly inhibited human hepatoma cells proliferation. When Bel-7402 cells were pretreated with OA for 24 h, OA induced apoptosis and G₂/M phase cell cycle arrest in a concentration-dependent manner. Analysis of the cell cycle regulatory proteins demonstrated that OA decreased the protein levels of cyclin B1, but increased the protein levels of p-Cdk1 (Tyr15) and p-Cdc25C (Ser 216). Moreover, OA modulated the phosphorylation of protein kinases Chk1 and p2l. Western blotting assay also showed significant decrease of Bcl-2 protein expression and increase of Bax protein expression, the cytosol Cyt c level, cleaved-caspase-9 and cleaved-caspase-3 activity. These data suggest that OA produces anti-tumor effect via induction of G₂/M cell cycle arrest and apoptosis.
Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; drug therapy ; pathology ; Cell Line, Tumor ; G2 Phase Cell Cycle Checkpoints ; drug effects ; Humans ; Liver Neoplasms ; drug therapy ; pathology ; M Phase Cell Cycle Checkpoints ; drug effects ; Oleanolic Acid ; pharmacology

OBJECTIVETo evaluate the effects of the ethanol extract isolated from Weiqi Decoction (WQD-EE) on AGS cell proliferation and apoptosis.

METHODSBy using high-performance liquid chromatography with ultraviolet detectors (HPLC-UV) assay and MTT method, the main compounds in WQD-EE and cell viability were detected. And cell cycle distributions were determined by flow cytometry with propidium iodine (PI) staining while apoptosis was detected by flow cytometry with annexin V/PI double staining. Finally, caspase-3 activities were measured by colorimetric method and protein expression was determined by Western blotting.

RESULTSHPLC analysis showed that naringin (35.92 μg/mg), nobiletin (21.98 μg/mg), neohesperidin (17.98 μg/mg) and tangeretin (0.756 μg/mg) may be the main compounds in WQD-EE. WQD-EE not only inhibited AGS and MCF 7 cell proliferation in a dose-dependent manner, but also blocked cell cycle progression at G2/M stage as well as inducing cell apoptosis at concentrations triggering significant inhibition of proliferation and cell cycle arrest in AGS cells. While at 0.5 mg/mL, WQD-EE significantly increased caspase-3 activity by 2.75 and 7.47 times at 24 h and 48 h, respectively. Moreover, WQD-EE in one hand reduced protein expressions of p53 and cyclin B1, and in other hand enhanced protein expressions of cytochrome c and Bax. Protein levels of Bcl-2, Fas L and Fas were not significantly affected by WQD-EE.

CONCLUSIONSWQD-EE inhibits AGS cell proliferation through G2/M arrest due to down-regulation of cyclin B1 protein expression, and promotes apoptosis by caspase-3 and mitochondria-dependent pathways, but not by p53-dependent pathway.

Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; pharmacology ; Ethanol ; chemistry ; G2 Phase Cell Cycle Checkpoints ; drug effects ; Humans ; M Phase Cell Cycle Checkpoints ; drug effects ; Neoplasm Proteins ; metabolism ; Plant Extracts ; isolation & purification