Effect of mitogen-activated protein kinase signal transduction pathway on multidrug resistance induced by vincristine in gastric cancer cell line MGC803

AIM:To investigate the correlation between mitogen-activated protein kinase (MAPK) signal transduction pathway and multidrug resistance (MDR) in MGC803 cells.METHODS:Western blot was used to analyze the expression of MDR associated gene in transient vincristine (VCR) induced MGC803 cells, which were treated with or without the specific inhibitor of MAPK, PD098059.Morphologic analysis of the cells treated by VCR with or without PD098059 was determined by Wright-Giemsa staining. The cell cycle analysis was performed by using flow cytometric assay and the drug sensitivity of MGC803 cells which were exposed to VCR with or without PD098059 was tested by using MTT assay.RESULTS:Transient exposure to VCR induced P-gp butnot MRP1 or GST-π expression in MGC803 cells and the expression of P-gp was inhibited by PD098059.Apoptotic bodies were found in the cells treated with VCR or VCR+PD098059. FCM results indicated that more MGC803 cells showed apoptotic phenotype when treated by VCR and PD098059 (rate:31.23%) than treated by VCR only (rate:18.42%) (P<0.05).The IC50(284±13.2 μg/L) of MGC803 cells pretreated with VCR was 2.24-fold as that of negative control group (127±17.6μg/L) and 1.48-fold as that of the group treated with PD098059 (191±27.9μg/L).CONCLUSION:This study shows that the expression of P-gp can be induced by transient exposure to VCR and this induction can be prevented by PD098059, which can block the activity of MAPK. MAPK signal transduction pathway may play some roles in modulating MDR1 expression in gastric cancer.

Inhibition of mouse hepatocyte apoptosis via anti-Fas ribozyme

AIM: TO investigate the effects of anti-Fas ribozyme on Fas expression and apoptosis in primary cultured mouse hepatocytes.METHODS: Mouse hepatocytes were isolated by using collagenase irrigation. A hammerhead ribozyme targeting the Fas mRNA was constructed, and transfected into mouse hepatocytes via Effectene. Then Fas expression in mouse hepatocytes was detected by RT-PCR and western blotting.After being treated with anti-Fas antibody (JO2), hepatocytes viability was measured with MTI- assay. Caspase-3 proteolytic activity was detected, and cell apoptosis was measured according to Annexin V-FITC apoptosis detection kit.RESULTS: Fas expressed in primary mouse hepatocytes.Fas expression in hepatocytes transfected with anti-Fas ribozyme was decreased remarkably and correlated with the resistance to Fas-mediated apoptosis as determined by flow cytometry and caspase-3 proteolytic activity.CONCLUSION: AnU-Fas ribozyme can remarkably decrease the Fas expression in mouse hepatocytes, thus inhibit Fasmediated apoptosis in hepatocytes, It is suggested that anti-Fas ribozyme could significantly increase the resistance of transplanted hepatocytes to apoptosis and improve the survival of transplanted hepatocytes,

Clinical Efficacy and Molecular Mechanism of Nourishing Shen and Supplementing Marrow Principle in Treating β Thalassemia

Objective: To explore the possibility of using traditional Chinese medicine (TCM) in treating β thalassemia, its clinical effect and molecular mechanism of the action.Methods: According to the TCM theory of“Shen producing marrow”, the composite recipe, Yisui Shenxueling Granule (YSSXL), consisting of Chinese drugs for nourishing Shen and supplementing marrow (NS&SM) was given orally to 7 8 patients with β thalassemia (49 of the severe type and 29 of moderate type ), 3 times a day, 10 g each time (for children, the dose would be reduced proper ly), with 3 months as one therapeutic course, and no blood transfusion used in t he course. The clinical therapeutic efficacy and hematologic parameters in patie nts were observed, and systemic gene analysis was conducted with PAGE, PCR, PCR SSCP, RT PCR and DNA sequences analysis and mRNA detection, in order to s tudy the molecular mechanism from the relationships between genetic mutation and clinical efficacy, gene expression and its regulation. Results: YSSXL showed obvious therapeutic effect in treating β thalassemia. Gene analysis revealed that it did not change the genetic mutatio n type, but could obviously increase hemoglobin, fetal hemoglobin (HbF), γ/(β+ γ) globin ratio, γ globin mRNA expression and GM CSF mRNA expression in patients, as well as the GM CSFmRMA in marrow of mice after 60 Co radia tion. Conclusion: YSSXL has a remarkable therapeutic effect on β tha lassemia, and its possible mechanism is its action in unlocking γ gene, in creasing the γ globin expression and enhancing HbF synthesis so as to compe nsate for the gene defect. This study has opened a new path for the treatment of β thalassemia with TCM.

Immunoelectron microscopic localization of calmodulin in corn root cells

Methods for the localization of plant calmodulin by immuno-gold and immuno-peroxidase electron microscopy have been developed. In both corn root-cap cells and meristematic cells, calmodulin was found to be localized in the nucleus, cytoplasm, mitochondria as well as in the cell wall. In the meristematic cells, calmodulin was distinctly localized on the plasma membrane, cytoplasmic face of rough endoplasmic reticulum and polyribosomes. Characteristically, calmodulin was present in the amyloplasts of root-cap cells. The widespread distribution of calmodulin may reflect its pleiotropic functions in plant cellular activities.

Repression of allo-cell transplant rejection through CⅡTA ribonuclease P^+hepatocyte

AIM: Allo-cell transplant rejection and autoimmune responses were associated with the presence of class Ⅱmajor histocompatibility complex (MHC Ⅱ) molecules on cells.This paper studied the effect of Ribonuclease P (RNase P)against CIITA, which was a major regulator of MHCII molecules, on repressing the expression of MHCII molecules on hepatocyte.METHODS: M1-RNA is the catalytic RNA subunit of RNase P from Escherichia coli. It were constructed that M1-RNA with guide sequences (GS) recognizing the 452, 3408 site of CIITA by PCR from pTK117 plasmid, then were cloned into the EcoRI/Bg/II or EcoR//SalIsite of vector psNAV (osNAV-M1-452-GS, psNAV-M1-3408-GS) respectively. The target mould plate (3176-3560) of CIITA was obtained from Raji cell by RT-PCR, and then inserted into the XhoI/EcoRIof pGEM-7zf(+) plasmid (pGEM-3176). These recombinant plasmids were screened out by sequence analysis. psNAV-M 1-452-GS, psNAV-M1-3408-GS and its target RNA pGEM-3176 were transcribed and then mixed up and incubated in vitro. It showed that M1-3408-GS could exclusively cleave target RNA that formed a base pair with the GS. Stable transfectants of hepatocyte cell line with psNAVl-M1-3408-GS were tested for expression of class Ⅱ MHC through FCM, for mRNA abundance of MHCII, Ii and CIITA by RTPCR., for the level of IL-2 mRNA on T cell by mixed lymphocyte reaction.RESULTS: When induced with recombinant human interferon-gamma (IFN-γ), the expression of HLA-DR, -DP,-DQ on psNAV-M1-3408-GS+ hepatocyte was reduced 83.27 %, 88.93 %, 58.82 % respectively, the mRNA contents of CIITA, HLA-DR, -DP, -DQ and Ii decreased significantly.While T cell expressed less IL-2 mRNA in the case of psNAV-M1-3408-GS+ hepatocyte.CONCLUSION: The Ribonuclease P against CIITA-M1-3408-GS could effectively induce antigen-specific tolerance through cleaving CIITA. These results provided insight into the future application of M1-3408-GS as a new nucleic acid drug against allo-transplantation rejection and autoimmune diseases.

Inhibition of Leukemic Cell Telomerase Activity by Antisense Phosphorothioate Oligodeoxynucleotides

Objective To evaluate the effect of human telomerase reverse transcriptase (hTERT) gene antisense oligodeoxynucleotide (ASODN) ontelomerase activity in K562 cells.Methods Telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay (PCR-ELISA) in K562 cellstreated with ASODN and hTERT mRNA expression was detected by reverse transcriptase polymerase chain reaction (RT-PCR).Results The hTERT mRNA level was decreased, and teloraerase activity was significantly inhibited when the K562 cells were treated withASODN for 48 h.Conclusion It is suggested that hTERT ASODN might specifically inhibit telomerase activity of K562 cells at translation level, and it isfurther proved that hTERT gene has significant correlation with telomerase activity.

The Experimental and Clinical Study on the Effect of Curcumin on Cell Cycle Proteins and Regulating Proteins of Apoptosis in Acute Myelogenous Leukemia

To investigate whether the Bcl- 2 gene family is involved in m odulating mechanism of apoptosis and change of cell cycle protein induced by curcumin in acute myeloid leukemia HL - 6 0 cell line and primary acute m yelogenous leukem ic cells,the Bcl- 2 family member Mcl- 1,Bax and Bak and cell cycle proteins including P2 7kipl,P2 1wafl,cyclin D3and p Rbp- were selected and their ex- pression detected by SABC imm uno- histochem ical stain m ethod.The attitude of sub- G1 peak in DNA histogram was determined by FCM.The TU NEL positive cell percentage was identified by term inal deoxynucleotidyl transferase (Td T ) - m ediated Biotin d U NP end labeling technique.It was found that when HL - 6 0 cells were treated with 2 5μm ol/ L curcumin for 2 4 h,the expression level of Mcl- 1was down- regulated,but that of Bax and Bak up- regulated time- dependently.There was significant difference in the expression level of Mcl- 1,Bax and Bak between the curcumin- treated groups and control group(P<0 .0 5 - 0 .0 1) .At the sam e time,curcumin had no effect on progress of cell cycle in prim aty acute m yelogenous leukemia at newly diagnosis,but could in- crease the peak of Sub- G1 (P<0 .0 5 ) ,and down- regulate the expression of Mcl- 1and up- regulate the expression of Bax and Bak with the difference being statistically significant.The expression of P2 7kipl,P2 1wafl and p Rbp- were elevated and thatof cyclin D3decreased in the presence of curcum in. These findings suggested thatthe Bcl- 2 gene fam ily indeed participated in the regulatory process of apoptosis induced by curcumin in HL - 6 0 cells and AML cells.Curcumin can induce apoptosis of primary acute myelogenous leukemic cells and disturb cell cycle progression of HL - 6 0 cells.The m echanism appeared to be m ediated by perturbing G0 / G1 phases checkpoints which associated with up- regulation of P2 7kipl,P2 1wafl and p Rbp- expression,and down- regulation of cyclin D3.

Gene Analysis of Arsenic Trioxide—induced Apoptosis of Lymphoma Cells

Objective The effect of arsenic trioxide on apoptosis gene expression of Raji cell was explored when Raji cells were incubated with 0.5μmol/L of arsenic trioxide for 6h。Methods Cell culture,extraction and isolation of mRNA,preparation of probes labeled with fluorescence,hybridization technique of DNA chip(each chip containing 200 apoptosis genes,Chinese Shanghai Biostar,In.)were used.Results Arsenic trioxide induced significant changes in 10%(20/200 genes)of the apoptosis genes:18 genes were downregulated,only two upregulated.In particular,inhibitors of apoptosis protein,such as X-linked inhibitor of apoptosis protein,were significantly downregulated.P53 and the other apoptosis genes were also downregulatec.Of the upregulated genes,high expression of heat-shock protein could promote apoptosis of Raji cells.Conclusion The inhibitors of apoptosis protein play an important role in the process of arsenic trioxide-induced apoptosis of Raji cells.

Amplification of Surface Antigen P43 Gene and Its Application in Detection of Toxoplasma Gondii in Allogeneic Hematopoietic Stem Cell Transplantation

Objective:To establish a rapid,specific and sensitive diagnostic technique for the human Toxoplasma gondii infection in the recipi-ents with allogeneic hematopoietic stem cell transplantation and discuss its clinical significance.Methods:30 patients undergoing allogeneic hematopoietic stem cell transplantation were detected by using ELISA and PCR.Results:Among 30 recipients undergiong allogeneic hematopoietic stem cell transplantation,3 were positive for Toxoplasma gondiii antigen and 5 for surface antigen p43 gene with the positive rate being 13.3% and 16.67% respectively.20 healthy people(negative for anti-Tox antibody)were also tested by using ELISA and PCR.Conclusion:PCR is an accurate,relatively rapid,sensitive and specific method for detecting P43 gene of Toxoplasma gondii.Be-canuse PCR can be applied to a variety of different clinical samples,it can be considered as a valuable additional tool for identification of Toxoplasma gondii infections.

Inhibition of Telomerase Activity of Lymphoblastic Leukemic Cells by hTERT Antisense

To investigate the effect of antisense, human telomerase reverse transcriptase (hTERT) mRNA oligodeoxynucleotide on telomerase activity of lymphoblastic leukemic cells. Methods: Telomerase activity was measured by the telomerase PCR ELISA assay kit (TRAP), hTERT protein by immunochemistry and flowcytometry, hTERT mRNA expression by reverse transcription polymerase chain reaction (RT-PCR) assay and gel-image system. Results: Incubation of lymphoblastic leukemic cells (Jurkat, Raji and CEM cell lines) with 10 μmol/L AS PS-ODN could significantly decline the mRNA and hTERT after 72 h, and the telomerase activity was significantly down-regulated or inhibited. Conclusion: The hTERT AS PS-ODN was an excellent inhibitor for telomerase activity of lymphoblastic leukemic cells.

Effects of All－trans Retinoic Acid on hTERT Gene Expression and Telomerase Activity of HL－60 Cells

Objective: To investigate the effects of all-trans retinoic acid (ATRA) on human telomerase reverse transcriptase (hTERT) protein expression and telomerase activity in HL-60 cells. Methods: The expression of hTERT protein was assayed by immunofluorescence using fluoresce isothiocyanate label and telomerase activity was determined by polymerase chain reaction enzyme-linked immunoassay with HL-60 cells untreated or treated with ATRA. Cell cycle was analyzed by flow cytometry. Results: After treatment with 1μmol/L ATRA for 24, 48, 72 h, mean fluorescence intensity of hTERT protein in HL-60 cells was 61.87±4.36, 37.47±2.85， 33.45±2.37，respectively. There was a significant decrease in hTERT protein expression compared to the cells untreated, and the effect had statistically significant difference (P<0.05).Telomerase activity was decreased significantly in HL-60 cells treated with 1μmol/L ATRA for 48, 72h as compared to the cells untreated (P<0.05). Conclusion: ATRA could inhibit telomerase activity and hTERT gene expression in HL-60 cells.

口服抗凝药物实验室监测方法研究

对口服抗凝药物实验监测有关方法进行了探讨，介绍了一种简便易行较为敏感的实验方法“Hepato－Quick”。实验表明：此法所用试剂加入因子V和纤维蛋白原，大大提高了试验的特异性。所采用的稀释法，减少了非特异性抗凝物质对试验的干扰。该法突出的优点是可采用毛细血管血进行检测。比较表明：血浆法与毛细血管法有良的相关性（r＝0.9836，P＜0.001）。

Reversal of P—glycoprotein—mediated multidrug resistance by pyronaridine

An association between P-glycoprotein(Pgp) level and poor clinical outcome has been found.Efforts have been made to search for the modulators of tumor multidrug resistance (MDR) from the components of Chinese herbs and the molecules developed in China.Pyronaridine (PND)was found to be able to reverse MDR to doxorubicine(DOX) in K562/A02 and MCF7/ADR,expressing Pgp with more efficacy than verapamil.PDN increased the accumulation of DOX and reduced efflux of Rh123 in the two cell lines.The reversibility prersisted for at least 24h after removel of the drug from the culture medium.When administered orally or parenterally,PND significantly enhanced the in vivo antitumor activity of DOX in K562/A02 xenografts,but did not significantly increase the toxicity or alter the plasma pharmacokinetics of DOX.In view of PND has been safely used in clinic for the treatment of malaria for more than 20 years at high dose,the modulator might be the promision in the reversal of MDR in the clinic.

Investigation of Blood Trace Elements in Acute Leukemia Patients by PIXE

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Studies of Liposomal bcl-2 Antisense Oligode-oxynucleofide Induction of Apoptosis in Raji Cells

OBJECTIVE To explore the effect of liposomal G3139 and transfected antisense phosphorothioate oligodeoxynucleotides directed against the coding region of the bcl-2 messenger RNA and the translation site on apoptosis in Raji cells.METHODS Cytotoxic effects were measured by use of the MTT method; The expression levels of Bcl-2 protein were assayed by immunofiuorescence using a fluoresce isothiocyanate label. Apoptosis was determined by morphological observation and flow cytometric analysis.RESULTS The 2 antisense oligonucleotides and G3139 can reduce Bcl-2 protein levels and Raji cell viability (IC50=4.54, 4.72 and 4.26 μmol/L, respectively), and induce apoptosis. A scrambled sequence control oligonucleotide and empty liposomes did not alter cell viability, Bcl-2 protein expression or apoptosis rates. There was no difference in reducing Bcl-2 protein levels and apoptosis rates found among the 3 antisense oligonucleotides.CONCLUSION The 2 antisense oligodeoxynucleotides of bcl-2 messenger RNA can effectively induce apoptosis of Raji cells. The 2 antisense sequences and G3139 have a similarity in their antisense effect.

Experession of Bax in Lung Cancer Cell Apoptosis Induced by Peroxisome Proliferator－activated Receptor－γ Anoists

Objective:To discuss the relationship between Bax expression level and lung cancer cell apoptosis induced by peroxisome proliferator-activated receptor-γ(PPAR-γ) agonists.Methods:RT-PCR and Western blot analyis were used to detect PPAR-γ expression in the lung cancer cells,and TUNEL was used to detect apoptosis induced by PPAR-γ agnoists,while in situ hybridization and immunohistochemistry were used to monitor the changes of Bax mRNA and protein expression levels after apoptosis induced.Results PPAR-γ expression was detectable in two kinds lung cancer cells (including Non-small cell lung cancer and small cell lung cancer) ,and PPAR-γ agonists could inhibit lung cancer growth through inducing apoptosis.The apoptostic rates in control group,15d-PGJ2 group and cilitazone group were (1.86±0.49)%,(25.8±2.9)±,and (17.3±1.9)%,(P<0.01)respectively;Bax mRNA expression rates in the three groups were (8.75± 1.36)%,(66.2±12.86)%,and(29.5±6.5)%(P<0.01)respectively;Bax protein expression rates in the three groups were(9.2±1.45)%,(63±10.4)%,and (34.5±6.0）%(P<0.05) respectively.Conclusion PPAR-y is predicted to be a new targes in treating lung cancer in the future,and Bax is most likely to work in treating lung cancer apoptosis induced by PPAR-y agnoists as a factor to induce apoptosis.

ANTI-HUMAN PLATELET TETRASPANIN(CD9)MONOCLONAL ANTIBODIES INDUCE PLATELET INTEGRIN αbβ3 ACTIVATION IN A Fc RECEPTOR INDEPENDENT FASHION

This study characterized the activation of platelet integrin α bβ3 induced by two anti human platelet tetraspanin monoclonal antibodies(mAbs),HI117 and SJ9A4. Methods.Using 125 I labeled human fibrinogen(Fg),specific Fg binding to human platelets induced by HI117 and SJ9A4 was measured as indication of activation of platelet integrin αbβ3 by the two mAbs. Results.HI117 and SJ9A4(10μg/ml and 20μg/ml) induced evident specific Fg binding to human platelets,suggesting that the two mAbs evoked activation of platelet integrin αbβ3.Further study indicated that HI117 and SJ9A4 induced integrin αⅡbβ3 activation independent of platelet Fc receptors, and that HI117 and SJ9A4 induced integrin αbβ3 activation was inhibited by sphingosing, aspirin, apyrase, and/or PGI2. Conclusion.The anti platelet tetraspanin(CD9)mAbs,HI117 and SJ9A4, can induce platelet integrin αⅡbβ3 activation independent of Fc receptors.Three signaling pathways,i.e.thromboxane,secreted ADP, and cAMP pathways may be involved in the process,with protein kinase C activation presumably being the common step of the three pathways.

Clinical Analysis of 43 Patients with Ught Chain Multiple Myeloma

OBJECTIVE To investigate the clinical characteristics and laboratory findings of patients with light-chain multiple myeloma. METHODS Fourty-three patients with light chain myeloma over a 13year period were analyzed retrospectively and 43 cases with IgG type myeloma in the same period were used as control. RESULTS Of the 43 patients, 28 were male, 15 were female, with an overall mean age of 57 years (range, 36-71). At the time of onset, the main symptoms were fatigue and dizziness (23 cases, 53.5%) and bone pain (25, 58.1%). The main signs were anemia (28, 65.1%) and bone pressure pain (23, 53.5%). Of 39 patients with determined staging, 38 were in stage Ⅲ and 1 stage Ⅰ. Renal function examinations were performed for 31 patients. Among them, 16 were in stage ⅢB and 15 in ⅡA. Hypercalcemia (≥3 mmol/L) occurred in 2 cases. Of 18 patients, 3 had proteinuria ≥12 g per 24 hours. Osteolytic lesions appeared in 27 of 31 cases. No abnormal globulin peaks were found in the serum protein electrophoretic bands. Serum and urine immunoelectrophoresis showed that 10 cases were kappa light chain, 29 were lambda light chain and 4 were both. Nineteen patients received chemotherapy, of which 8 cases obtained complete remission and 11 had no remission. CONCLUSION Because of poor differentiation, skeletal destruction and renal dysfunction, light chain multiple myeloma patients have meager therapeutical efficacy and poor prognosis.

Extracorporeal regulation effect of cytokines combination on stem cell or progenitor of umbilical blood

AIM:To study the regulation effect of different cytokines combinations on stem cell or progenitor of umbilical blood when no blood serum and matrix exist. METHODS: Collect and analyze the 23 sample of umbilical blood. RESULTS:(1) The combination of SCF+Flk2/Flt3 ligand and(FL)±TPO can amplify CD34,+,CD34+Thy 1+,CD34+CD33+and LTC IC in umbilical blood effectively and rapidly.(2) After add solubility type (sIL 6R)of IL 6 and IL 6 receptor into this combination, the stem cell or progenitor proliferated prominently;When add IL 6 alone(without sIL 6R), the content of CD34+cells and LTC IC didn’t increased obviously in early stage, but the amplification of CFU Mix and BFU E was not prominent as CFU GM. (3)Detect apoptosis rate of cells by FITC Annexin Ⅴlabeled by membranous change in early stage of cellular apoptosis. After add Flt3L and /or IL 6+sIL 6R, the Annexin Ⅴpositive cells decreased from 15.2%～19.1%to 2.8%～3.5%. CONCLUSION: In suspending system composed with SCF+TPO+Flt3L+IL 6+sIL 6R without matrix and blood serum, the umbilical blood can not only produce large amount of committed progenitor but also keep certain quantitive hematopoietic cells of early stage.

Clonal Expansion and Cytotoxicity of TCRVβ Subfamily T Cells Induced by CML and K562 Cells

OBJECTIVE To investigate the anti-leukemia effect, the distribution and clonal expansion of TCRVβ subfamily T cells in T cells from cord blood and adult peripheral blood induced by CML cells and K562 cells in vitro. METHODS Peripheral blood T cells from one adult donor and 3 cases of cord blood were stimulated with CML cells and K562 cells and further amplified by a suspended T cell-bulk culture,in order to induce CML specific cytotoxic T lymphocytes. The induced T cells were further analyzed for the specific cytotoxicity in CML by LDH assay, the phenotype identification by indirect immunofiuorescence technique and the distribution and clonal expansion of TCRVβ subfamily by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan analysis, respectively. RESULTS Oligoclonal and oligoclonal tendency T cells with higher specific cytotoxicity from cord blood and adult peripheral blood could be induced by stimulation with CML cells and K562 cells. CONCLUSIONS Specific cytotoxic T cells for an anti-CML effect could be induced by CML cells and K562 cells .The induced T cells which have the characteristic of specific cytotoxicity against CML cells may come from the clonal expansion of TCRVβ subfamily T cells.