: AbstractObjective: To explore the effect and mechanism of curcumin on human T-cell acute lymphoblastic leukemia (T-ALL) cell apoptosis induced by Mcl-1 small molecule inhibitors UMI-77. METHODS: T-ALL cell line Molt-4 was cultured, and the cells were treated with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77 for 24 h. The MTT method was used to detect the cell survival rate after different treatment; According to the results of curcumin and UMI-77, the experimental settings were divided into control group, curcumin group (20 μmol/L curcumin treated cells), UMI-77 group (15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells) and curcumin+ UMI-77 group (20 μmol/L curcumin and 15 μmol/L Mcl-1 small molecule inhibitor UMI-77 treated cells), MTT method was used to detect cell proliferation inhibition rate, Annexin V-FITC/PI double staining method and TUNEL staining were used to detect cell apoptosis, DCFH-DA probe was used to detect cell reactive oxygen species, JC-1 fluorescent probe was used to detect mitochondrial membrane potential, Western blot was used to detect the expression levels of apoptosis-related proteins and Notch1 signaling pathway-related proteins. RESULTS: After the treatment of Molt-4 cells with different concentrations of curcumin and Mcl-1 small molecule inhibitor UMI-77, the cell survival rate was decreased (P<0.05); Compared with the control group, the cell proliferation inhibition rate of the curcumin group and the UMI-77 group were increased, the apoptosis rate of cell was increased, the level of ROS was increased, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, and the protein expression of Bcl-2 was reduced (P<0.05); Compared with the curcumin group or UMI-77 group, the cell proliferation inhibition rate and apoptosis rate of the curcumin+UMI-77 group were further increased, and the level of ROS was increased. At the same time, the protein expression of Bax, Caspase-3 and Caspase-9 in the cells were all increased, the protein expression of Bcl-2 was reduced (P<0.05); In addition, the mitochondrial membrane potential of the cells after curcumin treatment was decreased, and the proteins expression of Notch1 and HES1 were reduced (P<0.05). CONCLUSION Curcumin can enhance the apoptosis of T-ALL cells induced by Mcl-1 small molecule inhibitor UMI-77 by reducing the mitochondrial membrane potential, the mechanism may be related to the inhibition of Notch1 signaling pathway.
Apoptosis ; Apoptosis Regulatory Proteins ; Caspase 3/metabolism* ; Caspase 9/pharmacology* ; Cell Line, Tumor ; Curcumin/pharmacology* ; Humans ; Myeloid Cell Leukemia Sequence 1 Protein/metabolism* ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Reactive Oxygen Species/pharmacology* ; Sulfonamides ; Thioglycolates ; bcl-2-Associated X Protein/pharmacology*

The biflavonoid isochamaejasmin is mainly distributed in the root of Stellera chamaejasme L. (Thymelaeaceae) that is used in traditional Chinese medicine (TCM) to treat tumors, tuberculosis, and psoriasis. Herein, isochamaejasmin was found to show similar bioactivity against Bcl-2 family proteins to the reference Bcl-2 ligand (-)-gossypol through 3D similarity search. It selectively bound to Bcl-xl and Mcl-1 with Ki values being 1.93 ± 0.13 μmol·L(-1) and 9.98 ± 0.21 μmol·L(-1), respectively. In addition, isochamaejasmin showed slight growth inhibitory activity against HL-60 with IC50 value being 50.40 ± 1.21 μmol·L(-1) and moderate growth inhibitory activity against K562 cells with IC50 value being 24.51 ± 1.62 μmol·L(-1). Furthermore, isochamaejasmin induced apoptosis of K562 cells by increasing the intracellular expression levels of proteins of the cleavage of caspase-9, caspase-3, and PARP which involved in the Bcl-2-induced apoptosis pathway. These results indicated that isochamaejasmin induces apoptosis in leukemia cells by inhibiting the activity of Bcl-2 family proteins, providing evidence for further studying the underlying anti-cancer mechanism of S. chamaejasme L.
Antineoplastic Agents, Phytogenic ; pharmacology ; therapeutic use ; Apoptosis ; drug effects ; Biflavonoids ; pharmacology ; therapeutic use ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Gossypol ; pharmacology ; HL-60 Cells ; Humans ; Inhibitory Concentration 50 ; K562 Cells ; Leukemia ; drug therapy ; metabolism ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Phytotherapy ; Plant Extracts ; pharmacology ; therapeutic use ; Poly(ADP-ribose) Polymerases ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; antagonists & inhibitors ; metabolism ; Signal Transduction ; Thymelaeaceae ; chemistry ; bcl-2-Associated X Protein ; metabolism

OBJECTIVETo investigate the expression and significance of miR-125a and anti-apoptotic protein Mcl-1 in intestinal tissue after massive small bowel resection in intestinal adaptation.

METHODSSprague-Dawley rats (54 male rats, 8-week old) were divided into 3 groups randomly, including two control groups. Rats in the experiment group were subjected to 70% massive small bowel resection. Rats in the resection group underwent simple intestinal resection and anastomosis. Rats in the control group underwent laparotomy alone. A 5 cm intestine approximately 1 cm distal to the anastomosis was harvested a week after operation. Expression of Mcl-1 was assessed by immunohistochemistry and real-time PCR was used to detect the expression of miR-125a in intestinal tissue.

RESULTSThe positive expression of Mcl-1 in the experiment group was 18.8%(3/16), significantly lower than that in the control group(76.5%, 13/17) and the resection group (83.33%, 15/18)(both P<0.01). The expression of miR-125a in the experiment group was 1.92, significantly higher than that in the control group (1.01) and the resection group (1.05)(both P<0.01).

CONCLUSIONmiR-125a and anti-apoptotic protein Mcl-1 may play an important role in intestinal adaptation process and they may regulate each other through a certain pathway.

Anastomosis, Surgical ; Animals ; Disease Models, Animal ; Intestine, Small ; metabolism ; surgery ; Male ; MicroRNAs ; metabolism ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Rats ; Rats, Sprague-Dawley ; Short Bowel Syndrome ; metabolism

OBJECTIVETo investigate the impact of ethanol extracts from Sedum sarmentosum (ESB) on STAT-3 signaling and its probable molecular mechanism in inducing apoptosis.

METHODMTT assay was used to detect the impact of ESB on HepG2 cell proliferation. FITC-Annexin V-FITC /PI double-labeling were used to investigate the impact on hepatoma carcinoma cell apoptosis. Western blot analysis was used to test the expression levels of cell apoptosis-related proteins Caspase-3, Caspase-9, PARP, P-STAT-3 (Tyr705) , STAT-3, Bcl-2, Mcl-1.

RESULTESB could notably inhibit proliferation of HepG2 cells, and induce HepG2 cell apoptosis, with the dose-dependent inhibitory effect. In addition, ESB could inhibit STAT-3 signaling, down-regulate Mcl-1 and Bcl-2 expressions, and induce degradation/activation of apoptosis-related proteins Caspase-3 and Caspase-9 and PARP degradation in a dose-dependent manner.

CONCLUSIONESB inhibits HepG2 cell proliferation and induces apoptosis by inhibiting STAT-3 signaling and Mcl-1 and Bcl-2 expressions.

Apoptosis ; drug effects ; Blotting, Western ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Ethanol ; chemistry ; Flow Cytometry ; Hep G2 Cells ; Humans ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Plant Extracts ; chemistry ; pharmacology ; Poly(ADP-ribose) Polymerases ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; STAT3 Transcription Factor ; metabolism ; Sedum ; chemistry ; Signal Transduction ; drug effects ; Time Factors

Mcl-1 and Bcl-xL, key anti-apoptotic proteins of the Bcl-2 family, have attracted attention as important molecules in the cell survival and drug resistance. In this study, we investigated whether inhibition of Bcl-xL influences cell growth and apoptosis against simultaneous treatment of resveratrol and clofarabine in the human malignant mesothelioma H-2452 cells. Resveratrol and clofarabine decreased Mcl-1 protein levels but had little effect on Bcl-xL levels. In the presence of two compounds, any detectable change in the Mcl-1 mRNA levels was not observed in RT-PCR analysis, whereas pretreatment with the proteasome inhibitor MG132 led to its accumulation to levels far above basal levels. The knockdown of Bcl-xL inhibited cell proliferation with cell accumulation at G2/M phase and the appearance of sub-G0/G1 peak in DNA flow cytometric assay. The suppression of cell growth was accompanied by an increase in the caspase-3/7 activity with the resultant cleavages of procaspase-3 and its substrate poly (ADP-ribose) polymerase, and increased percentage of apoptotic propensities in annexin V binding assay. Collectively, our data represent that the efficacy of resveratrol and clofarabine for apoptosis induction was substantially enhanced by Bcl-xL-lowering strategy in which the simultaneous targeting of Mcl-1 and Bcl-xL could be a more effective strategy for treating malignant mesothelioma.
Adenine Nucleotides/*pharmacology ; Antimetabolites, Antineoplastic/*pharmacology ; Apoptosis/*drug effects ; Arabinonucleosides/*pharmacology ; Caspase 3/metabolism ; Caspase 7/metabolism ; Cell Line, Tumor ; Cell Proliferation/drug effects ; G2 Phase Cell Cycle Checkpoints/drug effects ; Gene Knockdown Techniques ; Humans ; Leupeptins/pharmacology ; Lung Neoplasms/metabolism/pathology ; M Phase Cell Cycle Checkpoints/drug effects ; Mesothelioma/metabolism/pathology ; Myeloid Cell Leukemia Sequence 1 Protein/antagonists & inhibitors/genetics/metabolism ; RNA Interference ; RNA, Messenger/metabolism ; RNA, Small Interfering/metabolism ; Stilbenes/*pharmacology ; bcl-X Protein/antagonists & inhibitors/*genetics/*metabolism

BACKGROUNDFarnesoid X receptor (FXR) regulates tumorigenesis, but its clinical significance in gallbladder cancer (GBC) remains unclear. This study investigated its clinical and prognostic significance in GBC patients, as well as its association with the anti-apoptotic protein, myeloid cell leukemia sequence 1 (MCL1) protein.

METHODSFXR and MCL1 expression in 42 primary GBC and 15 normal gallbladder tissues were analyzed by immunohistochemistry. The patients and samples were collected from Ren Ji Hospital from January 2005 to December 2010. Their association with clinicopathologic factors and prognosis, as well as the correlation between FXR and MCL1 protein expression were analyzed by statistical analyses.

RESULTSCompared with normal gallbladder tissues, FXR expression was decreased and MCL1 expression was increased in GBC, during progression of tumor node metastasis (TNM) stage. The Kaplan-Meier survival analysis showed that FXR low-expression and MCL1 over-expression were significantly associated with overall poor survival. Furthermore, multivariate analysis showed that FXR and MCL1 are both prognostic factors for GBC patients. FXR low-expression was significantly correlated with MCL1 over-expression.

CONCLUSIONFXR might be a new molecular marker to predict the prognosis of patients with GBC and a novel therapeutic target.

Adult ; Aged ; Aged, 80 and over ; Disease Progression ; Female ; Gallbladder Neoplasms ; diagnosis ; metabolism ; Gene Expression Regulation, Neoplastic ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Neoplasm Staging ; Prognosis ; Receptors, Cytoplasmic and Nuclear ; metabolism

OBJECTIVETo explore the effect of downregulation of Tiam1 by siRNA on the esophageal squamous cell carcinoma (ESCC) EC9706 cells, and provide theoretical basis for gene therapy of ESCC using Tiam1 as a molecular target.

METHODSTiam1 siRNA was transfected into EC9706 cells, and expression changes of Tiam1 mRNA and protein after transfection were detected by quantitative real-time PCR and Western blotting. Cell proliferation was analyzed using CCK-8 kit. Cell cycle and apoptosis of the EC9706 cells were assessed by flow cytometry. Cell cycle-related proteins and cell apoptosis-associated proteins were analyzed by Western blotting.

RESULTSCompared with the untreated group and control siRNA group, the relative expression levels of Tiam1 mRNA (1.00 and 0.11 ± 0.02) were not significantly different (P > 0.05). The relative expression levels of Tiam1 mRNA in the Tiam1 siRNA group at 24, 48 and 72 h after transfection were 0.30 ± 0.04, 0.09 ± 0.01 and 0.09 ± 0.006, respectively, significantly lower than that of the untreated group (P < 0.05 for all). The expression level of Tiam1 protein at 24 h after Tiam1 siRNA transfection in the EC9706 cells was 0.11 ± 0.02, significantly lower than that in the un-treated group (0.44 ± 0.05) and control siRNA group (0.44 ± 0.04, P < 0.05 for all). The percentages of G0/G1 cells in the Tiam1 siRNA group, untreated group and control siRNA group were (54.48 ± 2.14)%, (40.69 ± 1.85)% and (41.78 ± 1.31)%, respectively (P < 0.01). The percentages of S phase cells in the Tiam1 siRNA group, untreated group and control siRNA group were (27.18 ± 1.65)%, (32.32 ± 1.15)% and (30.35 ± 1.09)%, respectively (P < 0.01). The expression levels of cyclin D1 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.43 ± 0.02, 0.41 ± 0.01 and 0.11 ± 0.02, respectively (P < 0.05). The expression levels of p27 protein in the untreated group, control siRNA group and Tiam1 siRNA group were 0.10 ± 0.01, 0.09 ± 0.02 and 0.20 ± 0.02, respectively (P < 0.05). The ratios of early apoptotic cells in the untreated group, control siRNA group and Tiam1 siRNA group were (10 ± 0.9)%, (10 ± 0.5)% and (27 ± 0.7)%, respectively (P < 0.01). The expression levels of Mcl-1 protein in EC9706 cells of untreated group, control siRNA group and Tiam1 siRNA group were 0.47 ± 0.12, 0.48 ± 0.13 and 0.16 ± 0.02, respectively (P < 0.05). The expression levels of Bcl-2 protein in EC9706 cells of the untreated group, control siRNA group and Tiam1 siRNA group were 0.49 ± 0.08, 0.50 ± 0.05 and 0.04 ± 0.03, respectively (P < 0.05). The caspase-3 activities in the untreated group, control siRNA group and Tiam1 siRNA group were 2.3 ± 0.09, 2.3 ± 0.10 and 16.0 ± 1.50, respectively; and that of caspase-9 were 2.3 ± 0.08, 2.3 ± 0.11 and 14.5 ± 0.9, respectively (P < 0.05 for all).

CONCLUSIONSTiam1 siRNA can significantly inhibit the proliferation of esophageal cancer EC9706 cells, induce cell cycle arrest and cell apoptosis. These effects are related to the regulation of the expressions of cell cycle-related genes (cyclin D1 and p27) and cell apoptosis-related genes (Mcl-1, Bcl-1, caspase-3 and caspase-9) by Tiam1 siRNA.

Apoptosis ; Carcinoma, Squamous Cell ; genetics ; metabolism ; pathology ; Caspase 3 ; metabolism ; Caspase 9 ; metabolism ; Cell Cycle Checkpoints ; Cell Line, Tumor ; Cell Proliferation ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Down-Regulation ; Esophageal Neoplasms ; genetics ; metabolism ; pathology ; Guanine Nucleotide Exchange Factors ; genetics ; metabolism ; Humans ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; RNA Interference ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; T-Lymphoma Invasion and Metastasis-inducing Protein 1 ; Transfection

OBJECTIVETo investigate the effects of TcpC on human umbilical vascular endothelial cells (HUVECs) and its mechanisms.

METHODSHUVECs were co-cultured with TcpC secreting wild-type E. coli strain CFT073 (TcpC(wt)) or tcpc gene-deleted CFT073 mutant strain (TcpC(mut)) in transwell system,respectively. Apoptosis of HUVECs was analyzed by Annexin-V/PI double staining. Mitochondrial membrane depolarization was detected by JC-1 staining. Expression of apoptosis-related proteins in HUVECs was determined by Western blot.

RESULTSHUVECs showed morphological changes after co-cultured with TcpC(wt) for 24 h: the cells became detached and cell debris increased,and cell number was also decreased when compared to HUVECs co-cultured with TcpC(mut). The apoptosis of HUVEC cells co-cultured with TcpC(wt) for 24 h significantly increased,compared to that of control group and TcpC(mut) group (60.1% 9.7% compared with 9.0% 1.3% and 16.9% 0.4%,respectively, P<0.05); meanwhile the mitochondrial depolarization of HUVECs co-cultured with TcpC(wt) was significantly increased,compared to that in control and TcpC(mut) groups (64.5% 0.9% compared with 14.5% 2.1% and 15.6% 3.3%, respectively,P<0.05). Cleavage of PARP and inhibition of Mcl-1 and XIAP expression were seen in HUVECs co-cultured with TcpC(wt),but not in groups of control and TcpC(mut).

CONCLUSIONTcpC secreted from CFT073 can induce apoptosis of HUVECs through mitochondrial pathway, in which PARP is cleaved and Mcl-1 and XIAP expressions are inhibited.

Apoptosis ; drug effects ; Cells, Cultured ; Escherichia coli ; metabolism ; Escherichia coli Proteins ; pharmacology ; Human Umbilical Vein Endothelial Cells ; drug effects ; pathology ; Humans ; Membrane Potential, Mitochondrial ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Poly(ADP-ribose) Polymerases ; metabolism ; Virulence Factors ; pharmacology ; X-Linked Inhibitor of Apoptosis Protein ; metabolism

Animals ; Carcinogenesis ; Cell Cycle Proteins ; genetics ; metabolism ; Cyclin E ; metabolism ; F-Box Proteins ; genetics ; metabolism ; F-Box-WD Repeat-Containing Protein 7 ; Gene Silencing ; Genes, Tumor Suppressor ; Humans ; Mutation ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Neoplasms ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins c-myc ; metabolism ; Receptors, Notch ; metabolism ; Signal Transduction ; TOR Serine-Threonine Kinases ; metabolism ; Ubiquitin-Protein Ligases ; genetics ; metabolism

OBJECTIVETo detect the expression of phosphorylated-signal transducer and activator of transcription 3 (p-Stat3) and myeloid leukemia-1 (Mcl-1) as well as their correlation, and to investigate the functional role of Stat3 and Mcl-1 in the pathogenesis of esophageal squamous cell carcinoma (ESCC).

METHODSStat3 activity in ESCC cells was inhibited with JAK/Stat3 inhibitors (AG490 or JSI-124). Specific siRNA was used to inhibit the Stat3 expression. Cell apoptosis was detected by flow cytometry. Expression of Mcl-1 protein was determined by Western blotting. Expression of phospho-Stat3 (Tyr705) and myeloid leukemia-1 (Mcl-1) proteins in ESCC tissues was detected by tissue microarray and immunohistochemistry. The relationship between p-Stat3 or Mcl-1 aberrant expression and clinicopatholohical features of ESCC was analyzed. The correlation of their expression was also analyzed.

RESULTSSuppression of the Stat3 signaling activation in ESCC cells led to marked apoptosis, and dramatic reduction of Mcl-1 protein. The positive rate of phospho-Stat3 (Tyr705) expression was 45.0% in 50/111 of the ESCC tissue samples. The lower the degree of tumor differentiation, the higher the positive rate of phospho-Stat3 (Tyr705), showing a significant difference (P = 0.018). The positive rate of Mcl-1 protein expression was 72.1% (80/111), and the lower the degree of tumor differentiation was, the higher there was the positive rate of Mcl-1, with a significant difference (P = 0.026). There was a positive correlation between the expressions of p-Stat3 and Mcl-1 proteins (P = 0.012).

CONCLUSIONSIn a subset of ESCC tissues, p-Stat3 (Tyr705) and Mcl-1 are overexpressed and positively correlated with each other, and both are correlated with tumor differentiation. Persistent activation of Stat3 contributes to apoptotic resistance in ESCC cells, and may be at least partly mediated through upregulation of Mcl-1.

Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Differentiation ; Cell Line, Tumor ; Cell Survival ; drug effects ; Esophageal Neoplasms ; metabolism ; pathology ; Humans ; Myeloid Cell Leukemia Sequence 1 Protein ; metabolism ; Neoplasm Grading ; Neoplasm Staging ; Phosphorylation ; RNA, Small Interfering ; genetics ; STAT3 Transcription Factor ; antagonists & inhibitors ; genetics ; metabolism ; Tyrphostins ; pharmacology