Reversal of multidrug resistance of the drug resistant human multiple myeloma cell line MOLP-2/R by curcumin and its relation with FA/BRCA pathway / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the reverse effect of mutidrug resistance of curcumin combined with melphalan on the mutidrug-resistant human multiple myeloma cell line MOLP-2/R and the relation with FA/BRCA pathway.</p><p><b>METHODS</b>The inhibitory effects of the drugs on the growth of MOLP-2/R cells were determined by MTT assay. Cell cycle analysis, intracellular drug concentration and apoptosis were assayed by flow cytometry. The expression of FANCD2 monoubiquitination was determined by Western blot analysis.</p><p><b>RESULTS</b>Co-administration of curcumin and melphalan had an synergistic inhibitory effects on the proliferation, IC50 of melphalan with 10 micromol/L curcumin reduced from 45.5 micromol/L to 19 micromol/L in MOLP-2/R cells. The apoptosis percentage of MOLP-2/R cells was significantly increased from (23.3 +/- 0.6)% to (52.6% +/- 0.8)% by the treatment of melphalan 20 micromol/L plus curcumin 10 micromol/L with the increased percentage of cells in the G2/M phase (from 9.1% to 18.5%) and enhanced intracellular drug concentration of MOLP-2/ R cells (from 15.2 +/- 0.3 to 21.4 +/- 0.8 ). The effects were accompanied with inhibition of FA/BRCA pathway by down regulation of FANCD2 protein monoubiquitination.</p><p><b>CONCLUSION</b>Curcumin combined with melphalan results in synergistic effects and reverses multiple drug resistance of MOLP-2/R cells effectively. The inhibition of FA/BRCA pathway may be the mechanism.</p>

Protection against doxorubicin-induced oxidative damage in normal blood cells by naringenin / 中国实验血液学杂志

The objective of this study was to investigate the protection by naringenin against doxorubicin-induced oxidative damage in normal blood cells. Inhibiting effects of naringenin, doxorubicin and naringenin combined with doxorubicind on K562 cells and polymorphonuclear leukocytes were detected with MTT method, the level of reactive oxygen species (ROS) and lipid peroxidation (MDA), the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were examined with spectrophotometric method in the K562 cells and polymorphonuclear leukocytes. The results indicated that the proliferation of K562 cells was not inhibited by the cytotoxicity of doxorubicin in combination of naringenin with doxorubicin. As compared with the doxorubicin, the addition of naringenin after doxorubicin for 1 hour, the levels of reactive oxygen species (ROS) and lipid peroxidation (MDA) obviously decreased, the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) obviously increased in the polymorphonuclear leukocytes, but these were not changed obviously in K562 cells. It is concluded naringenin can protect against doxorubicin-induced oxidative damage in normal blood cells. The mechanism of naringenin may be elevating activities of antioxidant enzyme and degrading oxidative production level in normal blood cells, and meanswhile decreasing level of oxidative products.

Mechanism of ligustrazine promoting hematopoietic reconstitution in syngenic bone marrow transplanted mice / 中国实验血液学杂志

The objective of this study was to investigate the effect of ligustrazine on the expression of stem cell factor mRNA (SCF) in bone marrow tissue and explore the mechanism of hematopoietic reconstitution after bone marrow transplantation (BMT). The colony forming unit of spleen (CFU-S) were counted, the survival rate at days 7, 14 and 21 after BMT were measured, as well as the expression level of SCF mRNA was detected by RT-PCR. The results showed that in ligustrazine group CFU-S counts on day 10 and survival rate, expression level of SCF mRNA on day 7, 14 and 21 after BMT were higher than that in the control group (p < 0.01 or p < 0.05). In conclusion, ligustrazine promotes the recovery of hematopoietic cells in bone marrow, enhances the repair of bone marrow microvessels, and then improves bone marrow microenvironment and promotes hematopoietic reconstitution.

Relation of apoptosis of K562 cells induced by naringenin in vitro to enzyme activity changes of caspase-3 and caspase-8 and expression of FAS/FASL proteins / 中国实验血液学杂志

The objective of this study was to investigate the apoptosis-inducing effect and underlying mechanism of naringenin (NGEN) on K562 cells in vitro. The inhibition of NGEN on K562 cells was evaluated by means of MTT assay so as to observe the cytotoxicity of NGEN; The morphological changes of the cells treated by NGEN were observed by transmission electron microscope; cell apoptosis rate influenced by NGEN was assessed by flow cytometry; the enzyme activity changes of caspase-3 and caspase-8 in the process of NGEN-induced K562 apoptosis were detected by Caspase Colorimetric Assay Kit; immunohistochemistry technique was used to detect FAS, FASL protein expression in K562 cells. The results showed that the growth of cells was inhibited by NGEN in dose-and time-dependent manners (p<0.05); NGEN-induced K562 cells apoptosis and sub-G1 peak was observed; some typically early and final phase changes of cell apoptosis were revealed under transmission electron microscope; the enzyme activity of caspase-3 and caspase-8 and the expression of FAS remarkably increased, meanwhile the expression of FASL was down-regulated (p<0.05). It is concluded that NGEN exerts anti-cancer effect by inducing K562 cell apoptosis, and the regulation of the expression of FAS and FASL. The caspase-3 and caspase-8 co-pathway brings about one of the mechanisms.

Construction of FANCA mutant protein from Fanconi anemia patient and analysis of its function / 中华血液学杂志

<p><b>OBJECTIVE</b>To study FANCA protein expression in Fanconi anemia patient's (FA) cells and explore its function.</p><p><b>METHODS</b>FANCA protein expression was analyzed in 3 lymphoblast cell lines derived from 3 cases of type A FA (FA-A) patients using Western blot. Nucleus and cytoplasm localization of FANCA protein was analyzed in one case of FA-A which contained a truncated FANCA (exon 5 deletion). The FANCA mutant was constructed from the same patient and its interaction with FANCG was evaluated by mammalian two-hybrid (M2H) assay.</p><p><b>RESULTS</b>FANCA protein was not detected in the 3 FA-A patients by rabbit anti-human MoAb, but a truncated FANCA protein was detected in 1 of them by mouse anti-human MoAb. The truncated FANCA could not transport from cytoplasm into nucleus. The disease-associated FANCA mutant was defective in binding to FANCG in M2H system.</p><p><b>CONCLUSIONS</b>FANCA proteins are defective in the 3 FA-A patients. Disfunction of disease-associated FANCA mutant proved to be the pathogenic mutations in FANCA gene. Exon 5 of FANCA gene was involved in the interaction between FANCA and FANCG.</p>

Expression of survivin and P63 protein in B cell non-Hodgkin's lymphoma and their effects on cell apoptosis and proliferation / 中国实验血液学杂志

The study was aimed to explore the possible roles of survivin and P63 protein in the development and progression of B cell non-Hodgkin's lymphoma (B-NHL) and their relation with cell apoptosis and proliferation. TdT-mediated dUTP nick end labeling (TUNEL) and immunohistochemistry were used to detect the survivin and P63 protein expression, cell apoptosis and proliferating cell nuclear antigen (PCNA) level in 43 cases of B-NHL and 10 cases of reactive hyperplasia lymphoid (RHL) tissues. The results indicated that the positive rates of survivin and P63 protein expression were 69.8% (30/43) and 82.7% (30/43) respectively. The expression of survivin and P63 protein was 10% (1/10) and 40% (4/10) in RHL tissues of 10 cases. The expression of survivin in aggression B-NHL was higher than that in indolent B-NHL (83.3% vs 46.2%, P < 0.01). The expression of P63 proteins in aggressive B-NHL was higher than that in indolent B-NHL (86.7% vs 76.9%, P > 0.05). Apoptotic index (AI) and proliferation index (PI) correlated positively with expression of survivin (r = 0.429, P < 0.01; r = 0.348, P < 0.01), and so do with expression of P63 proteins (r = 0.451, P < 0.01; r = 0.369, P < 0.05). In addition, AI and PI were positively related (r = 0.598, P < 0.001). It is concluded that survivin may participate in the regulation mechanism of B-NHL cell apoptosis and proliferation, P63 as an oncogene enhances proliferation and takes part in the development of B-NHL. There may be a close relationship between survivin and P63 protein in the regulation of lymphocyte proliferative kinetics.