Relationship of TGF-β and IL-4R gene polymorphisms with risk of classical Hodgkin lymphoma / 中华血液学杂志

<p><b>OBJECTIVE</b>This study was aimed to analyze the relationship between single nucleotide polymorphisms of transforming growth factor-β1 G-800A and C-509T, interleukin-4 receptor V75I and susceptibility of CHL in adults.</p><p><b>METHODS</b>Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was applied to analyze the expressed alleles of the selected SNP loca. The relationship between genomic polymorphisms of TGF-β1 and IL-4R and susceptibility of CHL were coupled with clinical data.</p><p><b>RESULTS</b>TGF-β1G-800A and TGF-β1C-509T had obvious linkage equilibrium (D' = 0.879, r(2) = 0.83, P = 0.020). GT haplotype distribution frequencies in mixed cellularity Hodgkin lymphoma cases and control group were of 53.1% and 34.2%, respectively, with statistically significant (OR = 2.35, P = 0.000); distribution frequencies of mutant gene T/T in disease and control groups were of 38.8% and 15.3%, respectively, also with statistically significant (OR = 3.654, P = 0.000); frequencies of nodular sclerosis CHL patients with IL-4R V75I mutant gene A/A in disease and control groups were of 19.2% and 41.75%, respectively, also with statistically significant (OR = 3.156, P = 0.000).</p><p><b>CONCLUSION</b>Single nucleotide polymorphisms of TGF-β1 G-800A, C-509T and IL-4R V75I has a significant correlation with Chinese susceptibility to classical Hodgkin lymphoma.</p>

Synergism between carnosic acid and arsenic trioxide on induction of acute myeloid leukemia cell apoptosis is associated with modulation of PTEN/Akt signaling pathway / 中国结合医学杂志

<p><b>OBJECTIVE</b>To investigate the synergistic effects of carnosic acid (CA) with arsenic trioxide (As₂O₃) on proliferation and apoptosis in HL-60 human myeloid leukemia cells, and the major cellular signaling pathway involved in these effects.</p><p><b>METHODS</b>HL-60 cellular proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis. Cell cycle distribution and apoptosis were monitored by flow cytometry. The activation of casepase-9, Bcl-2-associated agonist of cell death (BAD), p-BAD, p27, phosphatase and tensin homolog deleted on chromosome ten (PTEN), Akt, p-Akt was assessed by Western blot analysis. The expression of PTEN mRNA was tested by reverse transcription polymerase chain reaction (RT-PCR) analysis.</p><p><b>RESULTS</b>CA reduced HL-60 cell viability in a dose- and time-dependent manner, and induced G1 arrest and apoptosis. Moreover, CA upregulated PTEN expression, blocked the Akt signaling pathway, subsequently inhibited phosphorylation of BAD, reactivated caspase-9, and elevated levels of p27. CA also augmented these effects of As₂O₃.</p><p><b>CONCLUSION</b>CA might be a novel candidate of the combination therapy for leukemia treatment; these effects were apparently associated with the modulation of PTEN/Akt signaling pathway.</p>

Study on reversing mechanism of multidrug resistance of K562/A02 cell line by carnosic acid / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the effects of carnosic acid (CA) on reversal of the multidrug resistance (MDR) of human leukemia cell line K562/A02 and its mechanism.</p><p><b>METHODS</b>MTT assay was used to determine the sensitivity of K562/A02 cells to adriamycin (ADM) pre-and post-treated with CA. Flow cytometry (FCM) and laser scanning confocal microscopy (LSCM) were used to measure intracellular fluorescence intensity and concentration of ADM respectively. The expression level of mdr1 was detected by semi-quantitative RT-PCR. P-glycoprotein (P-gp) expression was detected by FCM and Western blot.</p><p><b>RESULTS</b>CA decreased IC(50) of ADM in K562/A02 cells from 16.31 µg/mL to 1.35 µg/mL, being a 12.08-fold decrease. The intracellular ADM fluorescence intensity of K562/A02 was increased from 17.05 to 60.53 after treated with CA (P < 0.01). In living K562/A02 cells, after treated with CA, the diffuse distribution of intracellular ADM was recovered in both nuclear and cytoplasm, and the concentration of intracellular ADM increased from 4.93µg/mL to 15.43µg/mL. RT-PCR assay showed that CA inhibited the expressions of mdr1 mRNA in K562/A02 cells (P < 0.01). Mean fluorescence intensity of P-gp detected by FCM in CA-treated K562/A02 was decreased to 22.80 as compared with that in untreated K562/A02 cells (44.40, P < 0.05).</p><p><b>CONCLUSION</b>CA can reverse the MDR of K562/A02 cells in vitro. The mechanism may be associated with down-regulation of mdr1 and inhibition of P-gp function.</p>

Experimental study on immunotherapy with dendritic cell in leukemic mice model / 中华血液学杂志

<p><b>OBJECTIVE</b>To explore the feasibility and efficiency of immunotherapy with dendritic cell (DC) in leukemic mice model after allogeneic bone marrow transplantation (allo-BMT).</p><p><b>METHODS</b>Mature DC were expanded from mice bone marrow mononuclear cells (MNC) by adding mouse granulocyte-macrophage colony stimulating factor (mGM-CSF) and interleukin-4 (mIL-4). Three days later they were pulsed with frozen thawing L7212 leukemia-related antigen. Mice bearing leukemia received allo-BMT at d 0, and then were divided into control group (A), T cells group (B) and DC + T cells group (C) to receive respective immune therapy at d 14. The survival rate, survival time, occurrence of graft-versus-host disease (GVHD), cytotoxicity of spleen cells and serum cytokine level were observed. The survivors in each group were rechallenged with L7212 cells to observe the immune response to the leukemia.</p><p><b>RESULTS</b>Mature DC were successfully induced from bone marrow MNC. In groups B and C, the relapse rates were 30% and 0%, while the long term survival rates after BMT was 30% and 70% respectively. Both of the differences were statistically significant (P < 0.05). However, the incidence of GVHD in these two groups were similar. The mean survival times were (32.95 +/- 13.29) days and (41.15 +/- 13.88) days, respectively (P < 0.01). MTT assay indicated that spleen cells from group C had specific killing activity to L7212 cells. Enzyme-labeled immunosorbent assay (ELISA) showed that the serum IL-2 level in group C was (419.75 +/- 26.66) pg/ml, being significantly higher than that in the other two groups (P < 0.01). When the survivors were rechallenged with L7212 cells, there was difference between the survival rates of groups C and B (85.7% vs 33.3%, P < 0.05).</p><p><b>CONCLUSION</b>Immunotherapy with leukemia related antigen-pulsed DC in combination with donor lymphocyte infusions is an effective approach to reinforce GVL effect and decrease relapse after allo-BMT.</p>