[Hydrogen and Oxygen Isotopic Characteristics of Different Water and Indicative Significance in Baiyangdian Lake].

In order to better understand the water cycle processes in Baiyangdian Lake, samples for precipitation, river water, lake water, and groundwater were collected in 2020 via the analysis of oxygen and hydrogen isotopes and the total dissolved solids. A combined approach including correlation analysis, end-member modeling, and evaporation modeling was used to identify hydrogen and oxygen isotopic characteristics of different water types and their indicative significance to evaporation, hydrodynamics, and lake-groundwater interactions. The results showed that the compositions of hydrogen and oxygen isotopes in surface water and groundwater differed from each other. The average values of δD and δ18O were the highest in samples from lake water in June, secondary for lake water in October, and the lightest in groundwater. The slope of the lake water line was lower than that of the local meteoric water line, which could be attributed to a greater evaporative enrichment in lake water. The water loss ratio was estimated to be 18.8%-42.3% in June and 2.7%-30.3% in October by applying an evaporation model using deuterium excess. Lake water isotopes exhibited highly spatial heterogeneity, which indicated that Baiyangdian Lake was a poor-mixed lake controlled by the complex hydrodynamic conditions. The values of δD and δ18O were lighter around the estuary area and higher in the district far from the estuary. Although the main water isotopes in areas such as channels had a short residence time, the spatial differences in lake water isotopes were not remarkable, which suggested that the well-mixed conditions of the lake water contributed to reducing the heterogeneity of the lake water isotopic compositions on a spatial scale. The contribution ratios of lake leakage to groundwater were 0-91.7% and varied spatially. It had a negative relationship with the buried depth of groundwater and the distance to the lakeshore. No obvious relationship was found between lake leakage magnitude and groundwater level gradient. This study could provide a theoretical basis and technical support for the sustainable development of water resources and ecological environment protection in Baiyangdian Lake.

Targeting of phospho-eIF4E by homoharringtonine eradicates a distinct subset of human acute myeloid leukemia.

More than half of the patients with acute myeloid leukemia (AML) fail to achieve long-term disease-free survival with current therapies and novel therapeutic strategies are urgently needed. The effects of homoharringtonine (HHT) on the growth of AML cell lines and primary leukemia cells were examined using MTT, colony formation assay. The effects of HHT on both eukaryotic translation initiation factor 4E (eIF4E) and phospho-eIF4E(p-eIF4E) were examined through western blot and immunofluorescence staining. HHT selectively reduced levels of p-eIF4E and its downstream oncoprotein Mcl-1, and potently inhibited in vitro and in vivo the growth of a distinct subset of AML cells and primary leukemia cells expressing high level of p-eIF4E through apoptosis. Our findings suggest that HHT might be a first-in-class p-eIF4E-targeted drug and offer a novel therapeutic option for AML patients expressing high level of p-eIF4E.

Polyphyllin I induces cell cycle arrest and apoptosis in human myeloma cells via modulating ß-catenin signaling pathway.

Multiple myeloma (MM) is an indolent B-cell disease characterized by clonal proliferation of malignant plasma cells. Multiple myeloma remains incurable despite new targeted drugs and development of drug resistance or intolerable toxicity emerges as a major problem. Therefore, design, identification, and validation of novel chemicals with therapeutic potential are clearly needed for MM treatment. Here, we explore polyphyllin I (PPI), a major active constituent extracted from Paris polyphyllin, its inhibitory effects and its mechanisms in MM cells in vitro. We found that PPI inhibited the proliferation of myeloma cells. The combination of PPI with dexamethasone, doxorubicin, arsenic trioxide, or bortezomib enhanced the inhibition of cell growth. As analyzed by flow cytometry, MM cells were arrested at G2/M phase and apoptotic cells increased in a time-dependent manner. Morphological changes of cells undergoing apoptosis were observed under light microscope. To explore the mechanism of apoptosis induced by PPI, we next examined whether the Wingless-Int (Wnt)/ß-catenin signaling pathway played a role in the PPI-induced growth inhibition in MM cells. The canonical Wnt signaling pathway is activated in MM cells through constitutively active ß-catenin, a messenger molecule relevant to growth, survival, and migration of MM cells. Western blotting was used to measure the protein levels of ß-catenin, and PPI treatment led to downregulating the expression of ß-catenin protein and was followed by inhibition of ß-catenin nuclear localization. As a result, ß-catenin downstream targets, such as cyclin D1 and survivin, were downregulated. To the best of our knowledge, this is the first report identifying anti-proliferative potency of PPI against myeloma cells. PPI blocks ß-catenin nuclear translocation and decreasing expression of the downstream targets of ß-catenin. Our results suggest that PPI is a novel inhibitor of ß-catenin activity with potential anti-myeloma efficacy.

Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/ß-catenin axis.

OBJECTIVE: To evaluate the effects of tetrandrine citrate, a novel tetrandrine salt with high water solubility, on the growth of imatinib (IM)-resistant chronic myeloid leukemia (CML) in vitro and in vivo, and reveal action molecular mechanisms. METHODS: Cell viability in vitro was measured using methyl thiazolyl tetrazolium (MTT) assay. CML cell growth in vivo was assessed using a xenograft model in nude mice. Bcr-Abl and ß-catenin protein levels were determined using Western blotting. Bcr-Abl messenger RNA (mRNA) was measured by reverse transcription polymerase chain reaction (RT-PCR). Flow cytometry (FCM) was used to determine cell cycle status. RESULTS: Tetrandrine citrate inhibited the growth of IM-resistant K562 cells, primary leukemia cells, and primitive CD34(+) leukemia cells, and their inhibition concentration that inhibited 50% of target cells (IC(50)) ranged from 1.20 to 2.97 µg/ml. In contrast, tetrandrine citrate did not affect normal blood cells under the same conditions, and IC(50) values were about 10.12-13.11 µg/ml. Oral administration of tetrandrine citrate caused complete regression of IM-resistant K562 xenografts in nude mice without overt toxicity. Western blot results revealed that treatment of IM-resistant K562 cells with tetrandrine citrate resulted in a significant decrease of both p210(Bcr-Abl) and ß-catenin proteins, but IM did not affect the Bcr-Abl protein levels. Proteasome inhibitor, MG132, did not prevent tetrandrine-mediated decrease of the p210(Bcr-Abl) protein. RT-PCR results showed that tetrandrine treatment caused a decrease of Bcr-Abl mRNA. FCM analysis indicated that tetrandrine induced gap 1 (G(1)) arrest in CML cells. CONCLUSIONS: Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and CML cells. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210(Bcr-Abl) mRNA and ß-catenin protein.

Novel synthetic derivatives of the natural product berbamine inhibit Jak2/Stat3 signaling and induce apoptosis of human melanoma cells.

Persistent Jak/Stat3 signal transduction plays a crucial role in tumorigenesis and immune development. Activated Jak/Stat3 signaling has been validated as a promising molecular target for cancer therapeutics discovery and development. Berbamine (BBM), a natural bis-benzylisoquinoline alkaloid, was identified from the traditional Chinese herbal medicine Berberis amurensis used for treatment of cancer patients. While BBM has been shown to have potent antitumor activities with low toxicity in various cancer types, the molecular mechanism of action of BBM remains largely unknown. Here, we determine the antitumor activities of 13 synthetic berbamine derivatives (BBMDs) against human solid tumor cells. BBMD3, which is the most potent in this series of novel BBMDs, exhibits over 6-fold increase in biological activity compared to natural BBM. Moreover, BBMD3, directly inhibits Jak2 autophosphorylation kinase activity in vitro with IC(50)0.69 µM. Autophosphorylation of Jak2 kinase at Tyr1007/1008 sites also was strongly inhibited in the range of 15 µM of BBMD3 in human melanoma cells at 4h after treatment. Following inhibition of autophosphorylation of Jak2, BBMD3 blocked constitutive activation of downstream Stat3 signaling in melanoma cells. BBMD3 also down-regulated expression of the Stat3 target proteins Mcl-1and Bcl-x(L), associated with induction of apoptosis. In sum, our findings demonstrate that the novel berbamine derivative BBMD3 is an inhibitor of the Jak2/Stat3 signaling pathway, providing evidence for a molecular mechanism whereby BBMD3 exerts at least in part the apoptosis of human melanoma cells. In addition, BBMD3 represents a promising lead compound for development of new therapeutics for cancer treatment.

[Inhibitory effect of 4-chlorobenzoyl berbamine on imatinib-resistant K562 cells in vitro and in vivo].

OBJECTIVE: To observe the inhibitory effect of 4-chlorobenzoyl berbamine (BBD9) on imatinib-resistant cell line K562 (K562/IR) in vitro and in vivo and explore the mechanisms. METHODS: The IC50 of BBD9 and berbamine (BBM) was determined by MTT assay. The expressions of p210(Bcr-Abl), IKKa, cytoplasmic and nuclear NF-κBp65 were determined using Western blotting in K562/IR cells following a 48-h exposure to 0.5 µg/ml BBD9 or 8 µg/ml BBM. Flow cytometry was used to analyze the cell viability, apoptosis and necrosis; Western blotting was employed to determine the expressions of PARP, caspase-3, caspase-9 and LC3II in K562/IR cells exposed to different concentrations of BBD9 for 48 h. In nude mouse models bearing K562/IR cell xenograft, the tumor weight, tumor regression, and body weight changes of the mice were measured after treatments with 15 mg/kg and 30 mg/kg BBD9 and 100 mg/kg imatinib. RESULTS: The IC50 of BBD9 and BBM was 0.73 µg/ml and 5.43 µg/ml, respectively. In K562/IR cell cultures, the expressions of p210(Bcr-Abl), IKKa and nuclear NF-κB p65 were all decreased following BBD9 and BBM treatments, but BBD9 produced more potent effect; cytoplasmic NF-κB p65 showed no obvious changes after the treatments. The cell apoptosis and necrosis increased with the concentrations of BBD9, which also dose-dependently increased the levels of cleaved caspase-3, csapase-9, PARP, and LC3II expression. In the tumor-bearing mouse model, BBD9 showed stronger effects than imatinib in reducing the tumor weight, promoting tumor regression, and increasing the body weight. CONCLUSION: BBD9 can effectively inhibit the growth of K562/IR cells in vitro and in vivo by activating cell apoptosis, necrosis and autophage pathways, down-regulating expressions of p210(Bcr-Abl) and IKKa and suppressing the cytoplasm-to- nucleus translocation of NF-κBp65.

Berbamine inhibits proliferation and induces apoptosis of KU812 cells by increasing Smad3 activity.

OBJECTIVE: The cytotoxic effect of berbamine on chronic myeloid leukemia (CML) cell line KU812 was evaluated, and the mechanisms of its action were explored. METHODS: The effect of berbamine on the KU812 cell growth was determined by methyl thiazolyl tetrazolium (MTT) assay. Flow cytometry was used to profile cell cycle alteration upon berbamine treatment. Reverse transcription polymerase chain reaction (RT-PCR) was carried out to determine the transcripts of transforming growth factor-ß (TGF-ß) receptors (TßRs), Smad3, c-Myc, cyclin D1, p21(Cip1)(p21), and p27(Kip1)(p27). Changes in the protein levels of total Smad3, phosphorylated Smad3, the downstream targets of Smad3, and specific apoptosis-related factors were evaluated by Western blotting. RESULTS: Berbamine inhibited KU812 cell proliferation in a dose- and time-dependent manner, and the half maximal inhibitory concentration (IC50) values for treatments of 24, 48, and 72 h were 5.83, 3.43, and 0.75 µg/ml, respectively. Berbamine induced G1 arrest as well as apoptosis in KU812 cells. Transcriptions of Smad3 and p21 were up-regulated, while those of TßRI, TßRII, c-Myc, cyclin D1 and p27 were not changed significantly. The protein levels of both total Smad3 and phosphorylated Smad3 were both up-regulated after berbamine treatment, together with decreased c-Myc and cyclin D1 and increased p21. Meanwhile, the levels of the anti-apoptotic proteins, such as Bcl-2 and Bcl-xL, were decreased, whereas pro-apoptotic Bax was increased. CONCLUSIONS: Berbamine suppresses KU812 cell proliferation through induction of cell cycle arrest in G1 and apoptosis. It activates Smad3 without additional stimulation of TGF-ß, and alters the levels of the Smad3 downstream targets, including c-Myc, cyclin D1 and p21. Our findings suggest that berbamine is a promising drug in the treatment of advanced stage patients with CML.

Berbamine, a novel nuclear factor kappaB inhibitor, inhibits growth and induces apoptosis in human myeloma cells.

AIM: We sought to investigate the effect of berbamine on the growth of human multiple myeloma cell line KM3 and elucidate the mechanism of its action. METHODS: MTT assay was used to determine the inhibitory effect of berbamine alone or combined with chemotherapeutic drugs. Flow cytometry was performed to characterize cell cycle profile in response to berbamine treatment. Western blot was used to measure the protein levels of p65, IkappaB Kinase alpha (IKKalpha), TNFAIP3 (A20), IkappaBalpha, p-IkappaBalpha, cyclinD1, Bcl-2, BAX, Bcl-x(L), Bid, and survivin. RESULTS: Berbamine inhibits the proliferation of KM3 cells in a dose- and time-dependent manner. Combination of berbamine with dexamethasone (Dex), doxorubicin (Dox) or arsenic trioxide (ATO) resulted in enhanced inhibition of cell growth. Flow cytometric analysis revealed that KM3 cells were arrested at G(1) phase and apoptotic cells increased from 0.54% to 51.83% for 36 h. Morphological changes of cells undergoing apoptosis were observed under light microscope. Berbamine treatment led to increased expression of A20, down-regulation of IKKalpha, p-IkappaBalpha, and followed by inhibition of p65 nuclear localization. As a result, NF-kappaB downstream targets such as cyclinD1, Bcl-x(L), Bid and survivin were down-regulated. CONCLUSION: Berbamine inhibits the growth of KM3 cells by inducing G(1) arrest as well as apoptosis. Berbamine blocks NF-kappaB signaling pathway through up-regulating A20, down-regulating IKKalpha, p-IkappaBalpha, and then inhibiting p65 nuclear translocation, and resulting in decreased expression of the downstream targets of NF-kappaB. Our results suggest that berbamine is a novel inhibitor of NF-kappaB activity with remarkable anti-myeloma efficacy.

[Berbamine induces apoptosis of multiple myeloma RPMI 8226 cells by activating GADD45/JNK pathway].

OBJECTIVE: To investigate the effect of berbamine (BBM) on multiple myeloma (MM) cell line RPMI 8226 and its mechanism. METHODS: MTT bioassay was used to examine the effect of berbamine on cell growth and IC(50) was calculated. Apoptosis was observed by flow cytometry (FCM) and DNA gelose electrophoresis. p53, p21, GADD45 mRNA were measured by RT-PCR. The alterations in p53, J NK, p-JNK and c-Jun proteins were detected by Western blot method. RESULT: The growth of RPMI 8226 cells was suppressed in a dose-dependent manner after treatment with BBM(P<0.05), and its IC(50) value was 3.83 microg/ml at 48 h. Both DNA ladder and FCM results showed that BBM induced apoptosis of RPMI 8226 cells with concomitant increase of activated p53, p21 and GADD45gamma mRNA. After treatment with BBM at 8 microg/ml for 24 h, the percentage of apoptotic cells increased from 1.07% to 24.84%. p-JNK and c-Jun proteins were activated. CONCLUSION: BBM can inhibit the growth of RPMI 8226 cells, which is associated with activation of GADD45/JNK signaling pathway and induction of cell apoptosis.

Berbamine induces Fas-mediated apoptosis in human hepatocellular carcinoma HepG2 cells and inhibits its tumor growth in nude mice.

Berbamine, a natural compound from the plant Berberis amurensis, is a traditional Chinese medicine mainly used in stimulating normal hematopoiesis in clinic. Our previous studies demonstrated that berbamine has anti-leukemia activity. In this study, we investigated the anticancer activity of berbamine against human hepatocellular carcinoma (HCC) HepG2 cells in vitro and in vivo. Berbamine treatment decreased the cell growth in a dose-dependent manner with an IC(50) value of 34.5 +/- 0.5 microM. Flow cytometric analysis of apoptosis using Annexin V/propidium iodide staining showed that the percentage of apoptotic cells was increased in a time-dependent manner. Berbamine treatment increased the expression level of Fas and P53, caused depolarization of mitochondrial membrane and decrease of membrane potential, and activated caspase-3, -8, and -9 in HepG2 cells. Berbamine-induced apoptosis could be blocked by the broad caspase inhibitor z-VAD-fmk. HepG2 human HCC xenograft mice treated with berbamine showed a significant reduction in tumor growth rates compared to saline-treated mice. These studies suggest that berbamine exerts anticancer effects on human HCC HepG2 cells in vivo and in vitro, the induction of p53 and the activity of the Fas apoptotic system may participate in the anticancer activity of berbamine in HepG2 cells.

[Deletion of the env region in HERV-H-X gene and its expression in colon cancer].

BACKGROUND & OBJECTIVE: We have identified a novel gene HERV-H-X from colon cancer tissue recently. This research was to analyze the deletion of the env region of HERV-H-X, to compare its expression with that of the env open reading frames (ORFs) in other HERV-H proviruses, and to study its differential expression in colon cancer and normal colon tissues. METHODS: Multiple alignments were performed for HERV-H-X and 3 other HERV-H proviruses (HERV-H/env62, HERV-H/env60, and HERV-H/env59) containing intact env ORF. HERV-H-X-specific polymerase chain reaction (PCR) and env ORF-common PCR for HERV-H/env62, env60 and env59 were conducted to study their expression in 8 pairs of colon cancer and adjacent normal tissues. Real-time quantitative PCR was conducted to study the differential expression of HERV-H-X in 17 pairs of colon cancer and adjacent normal tissues. RESULTS: The missing part in the env region of HERV-H-X corresponded to env ORFs in HERV-H/env62, HERV-H/env60 and HERV-H/env59. HERV-H-X was only detected in colon cancer tissues, while env ORFs were detected both in cancer and normal tissues. The expression of HERV-H-X was up-regulated in colon cancer tissues by 24.9 folds of that in normal tissues (P<0.01). CONCLUSION: HERV-H-X is highly expressed in colon cancer, but its up-regulation is not related to env gene as it lacks an env ORF.

Berbamine selectively induces apoptosis of human acute promyelocytic leukemia cells via survivin-mediated pathway.

BACKGROUND: Currently, resistance and relapse are still major problems in acute promyelocytic leukemia (APL) cases. Thus, new agents that override the resistance are crucial to the development of curative therapies for APL. In this study, we investigated the effects of berbamine on the proliferation of APL cell line NB4 and its possible mechanisms. METHODS: NB4 cells were treated with berbamine at different concentrations (0-64 microg/ml) for 72 hours. MTT assay was used to determine proliferation inhibition of NB4 cells. Cell apoptosis was evaluated by both flow cytometry (FCM) and morphological examination. PML/RAR-alpha and survivin mRNAs were measured by nested-RT-PCR and RT-PCR, respectively. Activated-caspase 3 was determined by FCM. RESULTS: Berbamine greatly inhibited the proliferation of NB4 cells in dose- and time-dependent manners, and its IC50 value was 3.86 microg/ml at 48 hours. Both morphological observations and FCM results showed that berbamine induced apoptosis of NB4 cells with concomitant increase of activated caspase-3 and decrease of survivin mRNA. After treatment with berbamine at 8 microg/ml for 48 hours, the percentage of apoptotic cells increased from 2.83% to 58.44% (P<0.01), and the percentage of cells with activated-caspase 3 elevated from 2.06% to 70.89% (P<0.01), whereas, level of survivin mRNA was reduced to 38.24% of control (P<0.01). However, no significant change was observed in PML/RAR-alpha mRNA. CONCLUSIONS: Berbamine induces caspase-3-dependent apoptosis of leukemia NB4 cells via survivin-mediated pathway, suggesting that berbamine may be a novel potential agent against APL with a mechanism distinct from that of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO).

Berbamine induces apoptosis in human hepatoma cell line SMMC7721 by loss in mitochondrial transmembrane potential and caspase activation.

OBJECTIVE: To investigate the effect of berbamine on human hepatoma cell line SMMC7721. METHODS: The effects of 24 h and 48 h incubation with different concentrations (0 to approximately 64 microg/ml) of the berbamine on SMMC7721 cells were evaluated using 3-4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT) assay. Hoechst 33258 staining was conducted to distinguish the apoptotic cell, and the appearance of sub-G1 stage was determined by PI (propidium iodide) staining, the percentage of apoptotic cell was determined by flow cytometry following annexin V/PI staining. Flow cytometry was performed to analyze the cell cycle distribution and the mitochondrial membrane potential (psi(m)); the expression of activated caspase3 and caspase9 was analyzed by Western-blot. RESULTS: The proliferation of SMMC7721 was decreased after treatment with berbamine in a dose- and time-dependent manner. Berbamine could induce apoptosis in SMMC7721 cells and could cause cell cycle arrest in G0/G1 phase, to induce loss of mitochondrial membrane potential (psi(m)) and activate caspase3 and caspase9. Berbamine-induced apoptosis could be blocked by the broad caspase inhibitor z-VAD-fmk. CONCLUSION: Berbamine exerts antiproliferative effects on human hepatocellular carcinoma SMMC7721 cells. The anticancer activity of berbamine could be attributed partly to its inhibition of cell proliferation and induction of apoptosis in cancer cells through loss in mitochondrial transmembrane potential and caspase activation.

[The mechanism of apoptosis of chronic myeloid leukemia cells induced by the novel p210 bcr/abl inhibitor berbamine].

OBJECTIVE: To investigate the mechanism of apoptosis of chronic myeloid leukemia (CML) cells induced by the novel p210 bcr/abl inhibitor berbamine. METHODS: Human Ph+ CML leukemia K562 cells, which express endogenous p210 bcr/abl protein, were cultured in RPMI 1640 and treated with berbamine as indicated time and dose. Flow cytometry (FCM) and Annexin-V-Fluos/PI staining kit were used to evaluate the apoptosis of leukemic cells; FCM and cytoperm/cytofix plus Caspase-3-McAb-PE were employed to measure the leukemic cells with activated Caspase-3. Phosphorylation of p210 bcr/abl protein in the leukemic cells were assessed by a combination of immunoprecipitation (IP) with c-abl antibody and Western blotting with p-Tyr (pY99) antibody. The protein levels of p210 bcr/abl, Hsp90 and Hsp70 in the leukemic cells were determined by Western blotting with antibodies to c-abl, Hsp90, and Hsp70 respectively. RESULTS: After treatment with berbamine at 8 microg/ml for 48 h, the percentages of leukemic cells expressing activated caspase-3 and apoptotic cells were 45.69% and 48.43% respectively. IP and WB results showed that berbamine at low concentration markedly inhibited phosphorylation of p210 bcr/abl protein in the leukemia cells, and the amount of phosphorylated p210 bcr/abl in the leukemia cells exposed to berbamine at 8 microg/ml for 6 h were only 8.41% of that of untreated leukemia cells without the protein levels of p210 bcr/abl down-regulated. Significantly, berbamine also down-regulated chaperone Hsp90 protein, and the amount of Hsp90 protein in the leukemia cells treated with berbamine at 8 microg/ml for 48 h accounted for 18.37% of that of the untreated leukemia cells. Berbamine at 8 microg/ml had no obvious effect on chaperone Hsp70 protein expression associated with the resistance of leukemia cells to apoptosis. CONCLUSION: (1) Berbamine induces caspase-3-mediated apoptosis of Ph+ leukemia cells through inhibiting phosphorylation of p210 bcr/abl protein and down-regulating its chaperone Hsp90 protein. (2) Unlike Hsp90 inhibitor GA that upregulates Hsp70, berbamine has no obvious effect on chaperone Hsp70 protein expression in leukemia cells, suggesting that berbamine may be a novel class of Hsp90 inhibitor, and further study is required.

[Effects of berbamine on growth of leukemia cell line NB4 and its mechanism].

OBJECTIVE: To determine effects of berbamine on the growth of leukemia cell line NB4 and explore its possible mechanisms. METHODS: The growth of NB4 cells was examined with MTT assay. Morphological analysis and DNA agarose electrophoresis were used to detect apoptosis in NB4 cells, and the apoptosis rate was measured by flow cytometry. The PML/RAR alpha mRNA was determined by nested-PCR, and the Survivin mRNA was tested by RT-PCR. The expression of caspase 3 protein in NB4 cells was evaluated by flow cytometry. RESULT: The growth of NB4 cells was inhibited significantly after treated with berbamine at different concentrations for different time points, the IC(50)value was 3.860 microg/ml at 48 hours. Morphology analysis showed the characteristics of apoptosis, and the DNA agarose electrophoresis showed the typical DNA ladder. The apoptosis rate increased from 2.83% to 58.44% after treated with berbamine at 12 microg/ml for 48 hours. The expression of PML/RAR alpha mRNA presented no significant changes, however, Survivin mRNA was decreased dramatically. The protein expression of Caspase 3 increased significantly from 2.06% to 70.89% after treated with berberine at a concentration of 12 mug/ml for 48 hours. CONCLUSION: Berbamine could inhibit the growth of leukemia cell line NB4. The induction of cell apoptosis may be one of the mechanisms for suppressing the growth of leukemia cell line NB4. Inhibition of Survivin mRNA and upregulation of Caspase 3 protein might be also involved in cell apoptosis.

[Overexpression of Shp-2 is associated with the unlimited growth and apoptosis resistance of p210 bcr-abl-mediated chronic myeloid leukemia].

OBJECTIVE: To investigate the expression level of Shp-2 tyrosine phosphatase in chronic myeloid leukemia (CML) and its relationship with the unlimited growth and apoptosis resistance of p210 bcr/abl-induced malignant cells. METHODS: In this study, p210 bcr/abl positive leukemia cell specimens were obtained from 25 CML cases, meanwhile, bone marrow and peripheral blood cell samples from 8 non-tumor individuals and 10 normal individuals were used as p210 bcr/abl negative controls. K562 and KU812 leukemia cells were used as p210 bcr/abl positive controls, and KG-1 leukemia cell line was used as Shp-2 positive control. Specimens of peripheral blood and bone marrow of 25 adult patients of chronic myelocytic leukemia, 15 males and 10 females, aged 28-64, were collected. Specimens of bone marrow of 8 basically healthy adult volunteers and specimens of peripheral blood of 10 healthy adult volunteers were used as controls. The total cell protein was collected and the expression of Shp-2 was examined by Western blotting. Human leukemia cells of the line K562 were cultured. Shp-2 specific sense and antisense oligonucleotides were added into the culture fluid respectively. The cell apoptosis was detected by flow cytometry (FCM). STI571, specific inhibitor of p210 bcr/abl was added into the cultured fluid of K562 cells, then Western blotting and FCM were used to detect the protein expression of Shp-2 and p210 bcr/abl, and cell apoptosis. RESULTS: Phosphorylated Shp-2 (pShp)-2 protein was overexpressed in 92% (23/25) of the CML cells, but lowly expressed or not expressed in the normal hematopoietic cells. The mean pShp-2 protein/beta-actin ratio of the primary CML leukemia cells was 0.91 +/- 0.62, significantly higher than those of the normal bone marrow cells and peripheral blood hematopoietic cells (0.16 +/- 0.09 and 0.03 +/- 0.05 respectively, both P < 0.01). The apoptotic rates of the CML cells treated by Shp-2 specific antisense oligonucleotide of the concentrations of 1 micromol/L and 4 micromol/L respectively for 72 h was 7.98% and 20.29% respectively, both significantly higher than that of the control group (4.06%, P < 0.01). The number of clone of CML cells treated by 0.25 micromol/L and 1.0 micromol/L Shp-2 specific antisense oligonucleotide for 7 days were 67% (37/60) and 11.9% (5/42) that of the control group. Twenty-four and 48 hours after the stimulation of STI571 the expression level of Shp-2 protein in the CML cells decreased time-dependently and the CML cell apoptotic rates were 31.15% and 38.69% respectively, both lower than that of the control group (33.6%). The number of clone of CML cells effected by 0.25 micromol/L and 1.0 micromol/L Shp-2 specific antisense oligonucleotide for 7 days was 67% (37/60) and 11.9% (5/42) that of the control group. Twenty-four and 48 hours after the stimulation of STI571 the expression level of Shp-2 protein in the CML cells decreased time-dependently and the CML cell apoptotic rates were 31.15% and 38.69% respectively, both lower than that of the control group (33.6%). CONCLUSION: (1) The pShp-2 protein is overexpressed in CML cells, which is associated with the unlimited growth and apoptosis resistance of malignant cells. (2) Shp-2 is upregulated by p210 bcr/abl oncoprotein in CML.

[Cytotoxicity and apoptosis of human osteosarcoma U2OS cells induced by recombinant soluble AZURIN].

OBJECTIVE: To investigate the effects of recombinant AZURIN protein of P. aeruginosa on growth and apoptosis of U2OS cells. METHODS: The AZURIN gene was amplified from the genome of P.aeruginosa by PCR, and cloned into prokaryotic expression vector pQE30. The soluble AZURIN protein was expressed in E. coli cells M15, then purified and refolded. After treatment of AZURIN, the cell cycle, proliferation and apoptosis were determined by morphological observation, MTT assay, flow cytometry(FCM) and DNA fragmentation assay. Mitochondrial membrane potential(DeltaPsim) was measured by FCM. RESULTS: The purity of recombinant protein AZURIN reached to 99.1%. Proliferation of U2OS cells were significantly inhibited 12 h after AZURIN (100-200 mg/L) treatment. Apoptosis peak and DNA ladder were observed. Mitochondrial membrane potential decreased gradually from 12 h to 72 h after AZURIN treatment. CONCLUSION: The recombinant AZURIN inhibit the growth of the human osteosarcoma U2OS cells and inducs apoptosis in vitroìwhich may be associated with the decrease of mitochondrial membrane potential.

[Molecular cloning of a novel retroviral NP9 gene of human endogenous retrovirus and its viral protein expression].

OBJECTIVE: To investigate the relationship between retroviruses and autoimmune diseases, to clone the novel retroviral NP9 gene from human endogenous retrovirus (HERV), and to construct its expression vector. METHODS: The viral NP9 gene was amplified and cloned by RT-PCR and T-A clone techniques, and its sequence was determined with Perkin-Elmer 377 DNA Sequencer. The amplified viral NP9 gene was subcloned into the prokaryotic express vector pQE30. The recombinant plasmids were identified by restriction endonuclease digestion and sequencing. The recombinant pQE30-NP9 protein was expressed in M15 host cells under the IPTG induction and showed with SDS-PAGE,and the corresponding NP9 viral protein was identified with Western blot analysis. RESULT: A specific band of 250 bp was amplified using RT-PCR from total RNA of peripheral blood mononuclear cells (PBMCs) from patients with systemic lupus erythematosus (SLE) and confirmed as the NP9 gene via T-A clone and DNA sequencing analyses. SDS-PAGE profile showed a clear protein band with a relative molecular weight 9 kD in the IPTG-induced samples, which was confirmed as viral NP9 protein by Western blot analysis. CONCLUSION: The NP9 gene has been successfully isolated and cloned from PBMCs of SLE patients and the corresponding NP9 viral protein expressed in prokaryotic expression vector.

Expression of a novel human retroviral NP9 gene and potential roles of its protein in systemic lupus erythematosus patients.

OBJECTIVE: To investigate the expression of a novel retroviral (NP9) gene transcripts and the possible role of its protein in systemic lupus erythematosus (SLE) patients. METHODS: The retroviral NP9 gene in SLE patients was isolated and cloned using RT-PCR and TA cloning techniques, and it was analyzed by sequencing. The expression of the NP9 genes in 40 patients with SLE and 48 normal controls using RT-PCR was detected. NCBI BLAST and DNASIS 3.1 software were used to analyze the features of protein of NP9 gene. RESULTS: The positive ratio (77.5%) of the mRNA expression of the retroviral NP9 gene in SLE patients is significantly higher than that (8.3%) in normal subjects (P<0.01). The recombinant NP9 protein comprises 74 AA with pI 9.59. Amino acid sequence analysis indicates that the retroviral NP9 protein shares higher homologies with several human proteins with important biological functions. CONCLUSION: SLE patients possess specific novel retroviral NP9 transcripts. The expression of the retroviral NP9 gene may involve in the genesis or development of SLE.

[Selective inducement effect of bacterial redox protein azurin on apoptosis of human osteosarcoma cell line U2OS].

BACKGROUND & OBJECTIVE: Bacterial redox protein azurin can selectively inhibit proliferation, and induce apoptosis in various human cancer cells. These in vitro findings have been confirmed in vivo in nude mice bearing tumor xenograft. Furthermore, azurin could diminish tumor volume in nude mice bearing tumor xenograft with no evidence of toxicity. The mechanism of its action is unknown. This study was designed to explore the effects of azurin on apoptosis of osteosarcoma cell line U2OS, and its molecular mechanism. METHODS: U2OS cells were cultured with different concentrations of azurin. Cell viability was detected by MTT assay. The 50% inhibitory concentration (IC(50)) of azurin was calculated by Bliss method. Apoptotic morphology and apoptotic body of U2OS cells were observed under fluorescent microscope, and transmission electron microscope. DNA ladder was observed through agarose gel electrophoresis. Cell apoptosis was determined by flow cytometry (FCM). Protein levels of Bax, Bcl-2, and Caspase-3 were quantified by Western blot. RESULTS: Azurin inhibited growth and induced apoptosis of U2OS cells in a dose-dependent manner 48 h after treatment, with the IC(50) of(114.54+/-7.65) mg/L. Moreover, its inhibitory effect was significantly higher on U2OS cells than on MG63 cells or L-02 cells under the same concentrations (P<0.05). When treated with 100 or 200 mg/L of azurin for 24 h, U2OS cells showed typical apoptotic morphology, typical DNA ladder bands were observed. No apoptotic feature was observed in control cells. Sub-G1 peak and apoptotic peak of U2OS cells were observed when exposed to 200 mg/L of azurin for 48 h with the apoptosis index of 35.8%, cell cycle was arrested in G1 phase. Bcl-2 was down-regulated when U2OS cells were treated with azurin for 24 h, while Bax and caspase-3 were up-regulated. CONCLUSIONS: Azurin could selectively induce apoptosis of human osteosarcoma U2OS cells. The induction of apoptosis by azurin may be closely associated with down-regulation of Bcl-2, up-regulation of Bax, and activation of Caspase-3.