Covalent Organic Framework-Based Nanomotor for Multimodal Cancer Photo-Theranostics.

Developing efficient integrated diagnosis and treatment agents based on fuel-free self-movement nanomotors remains challenging in antitumor therapy. In this study, a covalent organic framework (COF)-based biomimetic nanomotor composed of polypyrrole (PPy) core, porphyrin-COF shell, and HCT116 cancer cell membrane coating is reported. Under near-infrared (NIR) light irradiation, the obtained mPPy@COF-Por can overcome Brownian motion and achieves directional motion through self-thermophoretic force generated from the PPy core. The HCT116 cancer cell membrane coating enables the nanomotor to selectively recognize the source cell lines and reduces the bio-adhesion of mPPy@COF-Por in a biological medium, endowing with this NIR light-powered nanomotor good mobility. More importantly, such multifunctional integration allows the COF-based nanomotor to be a powerful nanoagent for cancer treatment, and the high infrared thermal imaging/photoacoustic imaging/fluorescence trimodal imaging-guided combined photothermal/photodynamic therapeutic effect on HCT116 tumor cell is successfully achieved. The results offer considerable promise for the development of COF nanomotors with integrated imaging/therapy modalities in biomedical applications.

Methylenetetrahydrofolate reductase gene polymorphisms association with the risk of diffuse large B cell lymphoma: a meta-analysis.

To date, case-control studies on the association between methylenetetrahydrofolate reductase (MTHFR) and diffuse large B cell lymphoma (DLBCL) have provided either controversial or inconclusive results. To clarify the effect of MTHFR on the risk of diffuse large B cell lymphoma, a meta-analysis of all case-control observational studies was performed. The fixed effects and random effects model showed that the C677T polymorphism was associated with a risk of DLBCL among East Asian populations, and A1298C polymorphism was not associated with a risk of DLBCL among Caucasian and East Asian populations. Our pooled data suggest evidence for a major role of MTHFR C677T polymorphism in the carcinogenesis of DLBCL among East Asian populations.

[Effect of gambogic acid on proliferation of SKM-1 cells and its mechanism].

The aim of this study was to explore the effect of gambogic acid (GA) on MDS SKM-1 cell proliferation, apoptosis and their possible mechanism. Cell proliferation was determined by MTT method. The apoptosis percentage and cell cycle regulation of SKM-1 cells were analyzed by flow cytometry. Morphological features were observed by light microscopy. The mRNA expression of bcl-2 and bax were detected by RT-PCR. The results showed that GA could inhibit the proliferation of SKM-1 cells in a dose- and time-dependent manner (IC50 was 0.37 µg/ml at 48 h), increase the apoptotic percentage of SKM-1 cells, and arrest cell cycle at the G0/G1. The expression of bax mRNA was up-regulated while that of bcl-2 mRNA was down-regulated in SKM-1 cells treated with GA for 48 h. It is concluded that GA can induce apoptosis, which may be related to its effect of arresting cells at phase of G0/G1 and down-regulating bcl-2/bax ratio.

Methylenetetrahydrofolate reductase gene polymorphisms association with the risk of follicular lymphoma: a meta-analysis.

To date, case-control studies on the association between methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and follicular lymphoma have provided controversial results. To clarify the effect of MTHFR polymorphisms on the risk of follicular lymphoma, a meta-analysis of all case-control studies was performed. The fixed effects and random effects model showed that the C677T polymorphism was associated with a risk of follicular lymphoma among Caucasian populations, and A1298C polymorphism was associated with a risk of follicular lymphoma among Asian populations. Our pooled data suggest evidence for a major role of MTHFR polymorphisms in the carcinogenesis of follicular lymphoma.

Endothelial progenitor cells in primary aldosteronism: a biomarker of severity for aldosterone vasculopathy and prognosis.

CONTEXT: Primary aldosteronism (PA) is associated with a higher incidence of cardiovascular events, probably through mineralocorticoid receptor (MR)-dependent endothelial cell dysfunction, in comparison with essential hypertension (EH). OBJECTIVE: Our objective was to investigate the number and function of endothelial progenitor cells (EPC) in PA and the relationship with arterial stiffness and disease progression. DESIGN AND SETTING: We conducted a prospective study of the change of EPC number and outcome of PA patients after treatment at a tertiary medical center. PRIMARY OUTCOMES: Changes in arterial stiffness and EPC number after treatment and the curability of hypertension were assessed. PATIENTS: A total of 113 PA patients (87 patients diagnosed with aldosterone-producing adenoma, 26 with idiopathic hyperaldosteronism) and 55 patients with EH participated. RESULTS: PA patients had higher arterial stiffness than EH patients (P = 0.006), with a lower numbers of circulating EPC and endothelial colony-forming units (P < 0.05). The differences were ameliorated at 6 months after unilateral adrenalectomy or treatment with spironolactone. Expression of MR was identified in the EPC. The number of circulating EPC was inversely correlated with the plasma aldosterone concentration (P = 0.021), arterial stiffness (P = 0.029) and serum high-sensitivity C-reactive protein (P = 0.03). High-dose aldosterone (10(-5) and 10(-6) m) attenuated EPC proliferation and angiogenesis in vitro. Among the 45 patients who underwent unilateral adrenalectomy, 32 (71%) were cured of hypertension. The preoperative number of EPC [log(EPC number percent) >-3.6] predicted the curability of hypertension after adrenalectomy (P = 0.003). CONCLUSIONS: The relative deficiency of EPC in PA patients may contribute to aldosterone vasculopathy, which can be reversed by adrenalectomy and spironolactone. High aldosterone levels attenuated EPC proliferation and angiogenesis. Circulating EPC number may be a valuable biomarker to identify PA patients with a high incidence of arterial stiffness and to predict postoperative residual hypertension of aldosterone-producing adenoma.

[Analysis of risk factors for relapse of 82 patients with hematologic malignancies after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To explore the risk factors for relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and the measures of prophylaxis and treatment. METHODS: We summarized the clinical data of 82 patients with hematologic malignancies who were treated in our hospital from August 2003 to December 2008. Factors including age, sex, ABO blood group disparity of donor and recipient as well as the type of donor, status of disease, HLA-match, conditioning regimen, whether or not having developed acute GVHD and chronic GVHD, infusion number of CD34(+) cells, relationship between CMV infection and relapse post-transplantation were considered and analyzed. RESULTS: Single factor analysis indicated that there were five independent risk factors related with the disease relapse (P < 0.05), including status of disease, time of diagnosis to transplantation, acute graft versus host disease (aGVHD), conditioning regimen, and chronic graft versus host disease (cGVHD). Simultaneously, the type of donor was a substantial factor (P < 0.01), determined by multi-factor Cox regression analysis. Cox regression analysis determined that disease status (OR = 2.58, 95%CI 1.26 - 5.01, P = 0.01), time from diagnosis to treatment (OR = 1.98, 95%CI 1.11 - 3.63, P = 0.025) and cGVHD (OR = 3.74, 95%CI 1.96 - 7.97, P < 0.001) were major factors for relapse of the patients who had undergone transplantation. CONCLUSIONS: Relapse remains the primary cause of failure after allo-HSCT. Status of disease, time from diagnosis to treatment and not cGVHD are the major risk factors. Effective prevention and treatment of relapse after engraftment can improve the efficacy of HSCT.

[Effect of hypoxia inducible factor1-α inhibitor on reversal of multidrug resistance of K562/A02 cell line].

OBJECTIVE: To study the reversal effect of the hypoxia inducible factor (HIF)-1α inhibitor, YC-1, on multidrug resistance of K562/A02 cells and its mechanism. METHODS: Pre- and post- incubation with adriamycin (ADM) alone or in combination with YC-1 for 48 h, the proliferation capacity of K562/A02 and K562 cells were evaluated by MTT assay. The apoptosis rate of K562/A02 cells after treated with 0, 5, 10 and 20 µmol/L YC-1 alone or in combination with 1 mg/L ADM and intracellular ADM concentration were analyzed by flow cytometry (FCM). The mRNA levels of HIF-1α and mdr1 genes were determined by semi-quantitative RT-PCR. The protein levels of HIF-1α and P-glycoprotein (P-gp) were detected by Western blot. RESULTS: The IC(50) of ADM for K562 and K562/A02 cells were (1.56 ± 0.07) mg/L and (42.98 ± 3.15) mg/L respectively. The resistance of K562/A02 cells to ADM was 27.55- fold higher of that of K562 cells. After treatment with YC-1 (5 µmol/L, 10 µmol/L, 20 µmol/L) for 48h, the resistances of K562/A02 cells to ADM were 24.63-, 16.38- and 10.71- fold increase respectively. After treatment of K562/A02 cell with YC-1 (0 µmol/L, 5 µmol/L, 10 µmol/L, 20 µmol/L) alone or in combination with 1 mg/L ADM for 48 h, the apoptotic rates were (1.9 ± 0.9)%, (4.9 ± 0.9)%, (5.8 ± 1.1)%, and (9.3 ± 1.4)% and (2.3 ± 0.7)%, (8.2 ± 1.2)%, (19.0 ± 1.7)%, and (34.5 ± 2.4)% respectively. The intracellular flucorescence intensity of ADM were 232 ± 33, 1300 ± 219, 1961 ± 240 and 3342 ± 269 in the combined treatment group. With the increase in YC-1 concentration, the levels of mdr1 mRNA reduced, while that of HIF-1α mRNA had no obvious change. Furthermore, the expressions of HIF-1α and P-gp were also decreased in K562/A02 cells. CONCLUSION: YC-1, as a HIF-1 inhibitor, can reverse multidrug resistance of K562/A02 cells through down-regulating HIF-1α and P-gp.

[Effects of hypoxia-inducible factor inhibitor on expression of HIF-1alpha and VEGF and induction of apoptosis in leukemic cell lines].

This study was purposed to investigate the effect of a hypoxia-inducible factor inhibitor (YC-1) on expression of hypoxia-inducible factor 1alpha (HIF-1alpha) and vascular endothelial growth factor (VEGF) as well as induction of apoptosis in leukemic cell lines. RT-PCR was used to determine the levels of HIF-1alpha mRNA and VEGF mRNA in K562, U937 and Jurkat cells. After treatment of U937 cell with 4 micromol/L YC-1, cell apoptosis was assayed by DAPI staining under fluorescent microscope and flow cytometry with Annexin V-FITC/PI staining; the expression levels of HIF-1alpha mRNA and VEGF mRNA were measured with RT-PCR; the expression levels of HIF-1alpha, VEGF, BAX, BCL-2 and caspase-3 proteins were measured by Western blot. The results showed that HIF-1alpha mRNA and VEGF mRNA were expressed in all three leukemia cell lines. After treatment of U937 cell with 4 micromol/L YC-1 for 0, 8, 16 and 24 hours, the changes of morphologic features of U937 cells could be observed under fluorescent microscope and the apoptotic rates significantly increased in time-dependent manner, they were (4.87 +/- 0.70)%, (27.27 +/- 2.00)%, (51.53 +/- 2.81) and (60.5 +/- 3.20)% respectively, the expression levels of VEGF mRNA reduced, while the expression levels of HIF-1alpha mRNA had no obviously changes.Furthermore, the expression of HIF-1alpha, VEGF and BCL-2 decreased, while the expression of BAX and caspase-3 increased, the ratio of BAX/BCL-2 increased in time-dependent manner (r = 0.973, p < 0.01). It is concluded that HIF-1alpha mRNA and VEGF mRNA are all expressed in in K562, U937 and Jurkat cells, YC-1 has significant effect on down-regulating the protein expression of HIF-1alpha and VEGF, and induces the apoptosis in U937. The mechanism of apoptosis in leukemic cells may involve in up-regulating BAX/BCL-2 ratio and expression of protein caspase-3.

[Effect of PDMP, a glucosylceramide synthase inhibitor, on reversion of daunorubicin resistance in human leukemia cell line K562/A02].

This study was purposed to investigate the reversal effect of glucosylceramide synthase (GCS) inhibitor D, L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP) hydrochloride, on multidrug resistance in K562/A02 cells and its mechanism. The IC(50) (the half maximal inhibitory concentration) of PDMP was measured by MTT method. Cell apoptosis and intracellular daunorubicin (DNR) concentration were detected by flow cytometry. The expression of GCS and mdr1 genes were assayed by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot. The results showed that the IC(50) of DNR in K562 and K562/A02 cells were 0.23 +/- 0.02 and 7.15 +/- 0.24 microg/ml respectively. When the concentration of PDMP was equal to or less than 20 micromol/L ( < / = 20 micromol/L), the obviously inhibitory effect on proliferation of K562 and K562/A02 cells was not observed, but both 20 micromol/L and 10 micromol/L PDMP could enhance the sensitivity of K562/A02 cells to DNR (p < 0.01) and the reversal multiples were 2.59 and 1.69 respectively. After treating with 20 micromol/L and 10 micromol/L PDMP for 48 hours, the concentration of DNR in K562/A02 cells increased (p < 0.05) and the apoptotic rate also was elevated (p < 0.01). The expressions of GCS and mdr1 genes were down-regulated at mRNA and protein levels after treating K562/A02 cells with 20 micromol/L PDMP for 48 hours. It is concluded that PDMP can enhance the sensitivity of K562/A02 cells to DNR by increasing cell apoptosis rate and accumulation concentration of DNR in cells, which may be related to down-regulated expressions of GCS and mdr1 genes.

[Reversal of multidrug-resistance in human leukemia cell line K562/A02 by tyrosine kinase inhibitors].

This study was aimed to investigate the reversal effect of tyrosine kinase inhibitors (TKI) Imatinib and Nilotinib on multidrug-resistant cell line K562/A02. The expression levels of mdr-1 mRNA and bcr-abl mRNA were assayed by RT-PCR. The protein levels of P-glycoprotein (P-gp) and P210 were detected by Western blot. The daunorubicin (DNR) accumulation in K562/A02 cells were analyzed by flow cytometry (FCM). The results showed that the 0.0625 micromol/L Imatinib or 5 nmol/L Nilotinib alone had no cytotoxic effect on the inhibition of K562/A02 cells. When K562/A02 cells were treated with Imatinib or Nilotinib alone for 48 hours, the expressions of mdr-1 mRNA, der/abl mRNA, P-gp and P210 protein were all down-regulated, furthermore the effect of Nilotinib was stronger than that of Imatinib. The detection of fluorescence intensity revealed that the DNR concentration in K562/A02 cells treated with Imatinib or Nilotinib alone for 48 hours were 7.85% and 12.02% of K562 cells respectively. It is concluded that the tyrosine kinase inhibitors show great effect reversing drug resistance of cells, moreover, the effect of Nilotinib is stronger than that of Imatinib.

[Construction and identification of Mdr-1-shRNA eukaryotic expression vector].

This study was purposed to construct and identify the short hairpin RNA (shRNA) eukaryotic expression vector for targeting gene mdr-1 which may play an important role in K562/A02. Short hairpin RNA (shRNA) aiming at the target sequence was to synthesized, the 3491-3509, 1539-1557and 3103-3121 nucleotide of mdr-1 mRNA were selected as targets. The selected nucleotides were cloned in the plasmid pGCSilencer-U6-neo-GFP respectively, and the resultant recombinant plasmids were named as pGY1-1, pGY1-2 and pGY1-3. The sequences of the recombinant plasmids were identified by DNA sequencing and PCR electrophoresis. The recombinant plasmids were transfected into the cell line K562/A02 by lipofection. After being transfected for 48 hours, the inhibition of mdr-1 mRNA was detected by real time-PCR, and P-gp expression was detected by Western blot. The results showed that the specific oligonucleotide was cloned into the vector successfully, and the expression of mdr-1 mRNA and P-gp in K562/A02 cells was reduced after transfecting the recombinant plasmid, as compared to the control group. It is concluded that the shRNA eukaryotic expression vector has been successfully established which can inhibit the expression of mdr-1 mRNA, setting up the basis to futher explore the effects of mdr-1 on cell line of K562/A02.

[Analysis on laboratory and clinical characteristics in 65 cases of myelodysplastic syndrome].

The aim of this study was to gain more insight into the understanding of myelodysplastic syndrome in the clinical and laboratory features. The clinical data of 65 patients with MDS were reviewed and analysed. According to FAB criteria, 65 patients were classified as follows: 27 patients with RA, 1 patient with RAS, 33 patients with RAEB, 3 patients with RAEB-T, and 1 patient with CMML. The median age of them was 66 years old (range 19-89 years), and 6 patients had a history of toxic exposure (secondary MDS). The bone marrow smears, bone marrow biopsy and cytogenetic examinations were performed in this study. The results showed that dysplasia was found in 64 patients examined with bone marrow smears (98.5%), among them trilineage dysplasia in 21 patients (32.3%), bilineage dysplasia in 33 patients (50.8%), only erythroid dysplasia in 8 cases (12.3%) and 2 patients (3.1%) only with myeloid dysplasia. The bone marrow biopsy was performed in 38 patients, abnormal localization of immature precursor (ALIP) occurred in 6 cases. 29 patients had abnormal karyotypes, accounting for 59.2% of the 49 patients subjected cytogenetic examination. The abnormal chromosome was the major cytogenetic abnormality, which occurred more often in secondary MDS and the patients with RAEB or RAEB-T. Among the 49 patients who had received cytogenetic examination, 15 patients transformed into AML with the incidence of 30.61%, but only 3 out of 20 patients in the group of normal chromosome transformed into AML (15%), while 12 out of 29 patients in the group of abnormal karyotypes transformed into AML (41.4%). The median time of following up was 35 months (range 2 - 106 months). The median survival time was 26.8 months and 8 months in the patients with normal karyotype and chromosome aberrations respectively. In conclusion, the incidence of MDS in our country is younger than that in Western countries, the rate of abnormal chromosome in high risk MDS is higher than that in low risk MDS. Meanwhile, those who have the change of chromosome are related to the transformation of MDS into AML and have shorter survival time than those MDS patients with normal karyotypes.

MDR reversal activity of bromotetrandrine in vitro and in vivo.

The present study was aimed to evaluate the MDR reversal activity of bromotetrandrine (BrTet) in vitro and in vivo. The inhibitory effects of adriamycin (ADM) used alone or in combination with BrTet or Tet on the proliferation of K562 and K562/A02 cells were evaluated by MTT assay. The ADM accumulation and the protein levels of P-glycoprotein (P-gp) were detected by flow cytometry. The mRNA levels of P-gp were determined by RT-PCR. The in vivo effect of BrTet and Tet was investigated by using nude mice grafted with sensitive human leukemia cell line K562 and MDR cell line K562/A02. The results showed that BrTet at 0.25, 0.5 and 1 micromol/L reversed the resistance to ADM in MDR K562/A02 cells in a dose-dependent manner. Flow cytometry suggested that BrTet significantly increased the intracellular accumulation of ADM in K562/A02 cells in a dose-dependent manner. BrTet also inhibited the overexpression of P-gp in K562/A02 cells, and down-regulated mdr1 expression. In nude mice bearing K562 xenografts on the left flank and K562/A02 xenografts on the right flank, intraperitoneal injection of 10 mg/kg BrTet significantly enhanced the antitumor activity of ADM against K562/A02 xenografts with inhibitory rates of 26.1%, while ADM alone inhibited the growth of K562/A02 xenografts only by 5.8%. No enhancement effect by BrTet was seen in K562 xenografts. It is concluded that BrTet shows significant MDR reversal activity in vitro and in vivo. Its activity may be related to the inhibition of P-gp overexpression and the increase intracellular accumulation of anticancer drugs. BrTet may be a promising-MDR modulator for eventual assessment in the clinic.

[Auto-hematopoietic stem cell transplantation for multiple myeloma accompanied with amyloidosis in four limbs].

The study was aimed to investigate the effective therapeutic method for patients with multiple myeloma accompanied with amyloidosis. A 58-year-old patient diagnosed as multiple myeloma accompanied with amyloidosis in four limbs was enrolled in this study. The various clinical and laboratorial examinations were performed, including bone marrow smear, immunologic test, radiography and so on. Patient received chemotherapeutic drugs and then autologous hematopoietic stem cell transplantation (auto-HSCT). The result showed that hematopoietic reconstitution was achieved at 23 days after auto-HSCT. Immunofixation electrophoresis was normal. There was only 0.6% plasma cells in the bone marrow. In conclusion, the auto-HSCT may be an effective treatment for multiple myeloma accompanied with amyloidosis in four limbs.

[Enhancement of reversing drug resistance of K562/A02 cells to adriamycin by ultrasound-induced cavitation].

This study was aimed to investigate the effects of low frequency and power ultrasound combined with adriamycin on apoptosis of drug-resistant leukemia cell line K562/A02 in vitro, to find out the parameters of optimal exposure, and to explore the possible mechanism reversing drug-resistance of K562/A02 cells. The K562/A02 cells in logarithmic growth phase were used in experiments. The experiments were divided into 4 groups: group control, group adriamycin (A02) alone, group ultrasound (US) alone and group A02+US. The trypan blue dye exclusion test and MTT assay were used to determine the cell viability; Wright's staining was used to detect the apoptosis; the flow cytometry was used to analyze the drug concentration, and the scanning electron microscopy was used to observe the changes of cell surface. The results showed that the significant differences in cell viability, intracellular adriamycin concentration and changes of cell membrane were found between ultrasound-treated and untreated cells in the presence of various concentration of adriamycin. The exposure to ultrasound at 20 kHZ, 0.25 W/cm2 for 60 seconds could obviously decrease LC50 of adriamycin to K562/A02 cells, while the exposure to ultrasound at 20 kHZ, 0.05 W/cm2 for 60 seconds could kill K562/A02 cells at once. After being treated by low frequency ultrasound, the small holes with diameter about 1-2 microm in the cell surface appeared. The ultrasound increased the adriamycin concentration in the cells, accelerated the formation of apoptotic bodies, and promoted apoptosis of adriamycin-resistant cells. It is concluded that the ultrasound at optimal parameters enhances inhibitory effect of adriamycin on drug-resistant cell line, thereby reverses drug-resistance of drug-resistant cell line through sound-hole effect in tumor cells resulting from ultrasound induced cavitation.

Synergistic effect of the combination of nanoparticulate Fe3O4 and Au with daunomycin on K562/A02 cells.

In this study, we have explored the possibility of the combination of the high reactivity of nano Fe3O4 or Au nanoparticles and daunomycin, one of the most important antitumor drugs in the treatment of acute leukemia clinically, to inhibit MDR of K562/A02 cells. Initially, to determine whether the magnetic nanoparticle Fe3O4 and Au can facilitate the anticancer drug to reverse the resistance of cancer cells, we have explored the cytotoxic effect of daunomycin (DNR) with and without the magnetic nano-Fe3O4 or nano-Au on K562 and K562/A02 cells by MTT assay. Besides, the intracellular DNR concentration and apoptosis of the K562/A02 cells was further investigated by flow cytometry and confocal fluorescence microscopic studies. The MDR1 gene expression of the K562/A02 cells was also studied by RT-PCR method. Our results indicate that 5.0 x 10(-7) M nano-Fe3O4 or 2.0 x 10(-8) M nano-Au is biocompatible and can apparently raise the intracellular DNR accumulation of the K562/A02 cells and increase the apoptosis of tumor cells. Moreover, our observations illustrate that although these two kinds of nanoparticles themselves could not lower the MDRI gene expression of the K562/A02 cells, yet they could degrade the MDR1 gene level when combining with anticancer drug DNR. This raises the possibility to combine the nano-Fe3O4 or nano-Au with DNR to reverse the drug resistance of K562/A02 cells, which could offer a new strategy for the promising efficient chemotherapy of the leukemia patients.

[Effect of tetrandrine in combination with droloxifen on the expression of NF-kappaB protein in K562 and K562/A02 cell lines].

OBJECTIVE: To study the effect of tetrandrine (Tet) in combination with droloxifen (DRL) on the expression of nuclear factor kappa B (NF-kappaB) in K562 and K562/A02 cell lines and its reversal mechanism. METHODS: The activation of NF-kappaB in K562 and K562/A02 cell lines and the effect of Tet or DRL alone or in combination on NF-kappaB protein expression were determined with immunocytochemistry and Western blotting respectively. RESULTS: (1) K562/A02 cells displayed higher level of NF-kappaB protein expression than K562 cells. (2) The application of Tet or DRL alone or in combination had no effect on NF-kappaB expression in K562 cells at 6 h and 12 h (P > 0.05). (3) Tet and DRL alone or in combination could significantly down-regulate NF-kappaB protein expression in nuclei of K562/A02 cells. The effect was more significant in combination than either alone. This effect was more significant at 12 h than at 6 h. CONCLUSIONS: (1) Activation of NF-kappaB may be involved in the mechanism of MDR of K562/A02 cell line. (2)Inhibition of NF-kappaB activation may be involved in the reversal of multidrug resistance in K562/A02 cells by Tet and DRL.

[Phenylhexyl isothiocyanate reducing U266 cell line methylation level of p16 gene].

This study was purposed to investigate whether phenylhexyl isothiocyanate (PHI) can reduce p16 gene methylation level or not. The myeloma U226 cell line was cultured with PHI of 0, 5, 10 micromol/L for 72 hours, then DNA was extracted. Hydrosulfite was used to treat the genome DNA of healthy adult, PCR amplification was carried out by using this DNA as template. The gene chip detecting methylation changes of 3 CpG in promoter region of p16 gene was constructed by designing a pair of probes which contain one methylated and one unmethylated probes. This pair of probes was used to detect 3 consecutive sites of CpG island in p16 gene. The standard curve was constructed by using gene chip after the methylated and unmethylated DNA were mixed at different ratio. Then treated samples of U266 cells were dotted on gene chip, obtained results were compared with standard curve to get the quantitative results. The results indicated that the probes on chip had excellent reproducible ability and precision, the methylation level of p16 gene in U266 cells treated with 0, 5 and 10 micromol/L of PHI was determined as 78.2%, 61.7% and 54.8%, respectively. It is concluded that the PHI can reduce the methylation level of p16 gene in U266 cells.

[Sodium valproate synergizes adriamycin to inhibit proliferation and induce apoptosis in myelodysplastic syndrome cell line].

The aim of this study was to investigate the tumor suppression efficacy of a histone deacetylase inhibitor, sodium valproate combined with adriamycin in the treatment of myelodysplastic syndrome cell line MUTZ-1. After treated with different concentrations of sodium valproate alone, adriamycin alone or combination of them, growth curve of MUTZ-1 cell line were detected; growth of the tumor cells were analyzed by flow cytometry and morphology method. The results indicated that when the myelodysplastic syndrome cell line MUTZ-1 was treated with adriamycin (0.039 microg/ml, 0.078 microg/ml, 0.156 microg/ml, 0.312 microg/ml, 0.4 microg/ml), the tumor growth inhibition rates were 5.08 +/- 0.79%, 12.32 +/- 2.39%, 23.65 +/- 1.34%, 43.33 +/- 2.38% and 47.85 +/- 1.46% (p < 0.05), 0.25 mmol/L sodium valproate did not show apoptosis effect, but could synergize adriamycin to promote apoptosis. When the myelodysplastic syndrome cell line MUTZ-1 treated with two drug combination, the tumor growth inhibition rates were 23.46 +/- 1.12%, 49.87 +/- 0.84%, 52.37 +/- 1.05%, 78.43 +/- 4.34% and 82.47 +/- 1.04% (p < 0.05), and displayed concentration-dependent manner. All the data above were significantly different from those in control (p < 0.05). Sodium valproate showed obvious effect at concentration of 0.078 microg/ml adriamycin. After treated with 0.25 mmol/L sodium valproate and 0.078 microg/ml adriamycin for 72 hours, MUTZ-1 cell line showed typical apoptosis morphological character. It is concluded that sodium valproate may enhance the efficacy of adriamycin on MUTZ-1 cell line.

[Nonmyeloablative peripheral blood stem cell transplantation for chronic myeloid leukemia in chronic and accelerated phases].

The aim of this study was to investigate the effect of nonmyeloablative peripheral blood stem cell transplantation in treatment of chronic myeloid leukemia in chronic phase (CML-CP) and accelerated phase (CML-AP). 24 patients with CML including 16 in CML-CP and 8 in CML-AP were treated with nonmyeloablative conditioning regimen for peripheral blood stem cell transplantation (PBHSCT). The conditioning regimen included fludarabine (30 mg/m(2)x6 d), busulphan [4 mg/(kg.d)x2 d] and CTX [350 mg/(m2.d)x2 d] combined with or without Ara-C. The donors were HLA-identical (n=20) and 5/6 antigen-matched (n=4). The dynamic observation of hematopoietic recovery in all patients was carried out. The results indicated that all the patients were successfully engrafted. The mean time for increase of the number of neutrophils to more than 0.5x10(9)/L and platelet more than 20x10(9)/L were 13 days and 11.5 days respectively. Out of 12 patients, 9 patients showed complete donor chimerism and 3 patients showed mixed chimerism at 30 days after transplantation. At 180 days after transplantation, 18 survival patients showed complete donor chimerism. 18 patients remained alive after a median follow-up length of 24 months (4-48 months). 2 cases died of severe acute GVHD and 1 case died of chronic GVHD, 2 cases died of interstitial pneumonia and 1 case died of relapsed. In conclusions, nonmyeloablative peripheral blood stem cell transplantation is an effective therapeutic method for CML patients in chronic phase and accelerated phase.