CD71-mediated liposomal arsenic-nickel complex combined with all-trans retinoic acid for the efficacy of acute promyelocytic leukemia

Clinically,arsenic trioxide(ATO)was applied to the treatment of acute promyelocytic leukemia(APL)as a reliable and effective frontline drug.However,the administration regimen of AsⅢwas limited due to its fast clearance,short therapeutic window and toxicity as well.Based on CD71 overexpressed on APL cells,in present study,a transferrin(Tf)-modified liposome(LP)was established firstly to encapsulate AsⅢin arsenic-nickel complex by nickel acetate gradient method.The AsⅢ-loaded liposomes(AsLP)exhibited the feature of acid-sensitive release in vitro.Tf-modified AsLP(Tf-AsLP)were specifically taken up by APL cells and the acidic intracellular environment triggered liposome to release AsⅢwhich stimulated reactive oxygen species level and caspase-3 activity.Tf-AsLP prolonged half-life of AsⅢin blood circulation,lowered systemic toxicity,and promoted apoptosis and induced cell differentiation at lesion site in vivo.Considering that ATO combined with RA is usually applied as the first choice in clinic for APL treatment to improve the therapeutic effect,accordingly,a Tf-modified RA liposome(Tf-RALP)was designed to reduce the severe side effects of free RA and assist Tf-AsLP for better efficacy.As expected,the tumor inhibition rate of Tf-AsLP was improved significantly with the combination of Tf-RALP on subcutaneous tumor model.Furthermore,APL orthotopic NOD/SCID mice model was established by 60CO irradiation and HL-60 cells intravenously injection.The effect of co-administration(Tf-AsLP+Tf-RALP)was also confirmed to conspicuous decrease the number of leukemia cells in the circulatory system and prolong the survival time of APL mice by promoting the APL cells’apoptosis and differentiation in peripheral blood and bone marrow.Collectively,Tf-modified acid-sensitive AsLP could greatly reduce the systemic toxicity of free drug.Moreover,Tf-AsLP combined with Tf-RALP could achieve better efficacy.Thus,transferrinmodified AsⅢliposome would be a novel clinical strategy to improve patient compliance,with promising translation prospects.

All-trans Retinoic Acid,Arsenic Trioxide,and Anthracycline-based Chemotherapy Improves Outcome in Newly Diagnosed Acute Promyelocytic Leukemia Regardless of FLT3-ITD Mutation Status

All-trans retinoic acid(ATRA)and pre-upfront arsenic trioxide(ATO)have revolutionized the therapy of acute promyelocytic leukemia(APL).However,internal tandem duplication of FMS-like tyrosine kinase 3(FLT3-ITD)mutations is associated with increased risk of relapse.The aim of this study was to analyze the prognostic impact of FLT3-ITD on APL patients who received remission induction with ATRA,idarubicin(IDA)and/or ATO,followed by ATRA plus ATO along with anthracycline,as consolidation therapy.A total of 72 patients newly diagnosed with APL were included in this study.83.3%of the patients achieved complete remission(CR)after induction therapy.FLT3-ITD mutations were detected in 16(22.2%)patients and closely related to bcr-3 PML-RARa transcript(P<0.001).The 5-year overall survival(OS)rate was 100%in both FLT3-ITDposltlve and FLT3-ITD^(negatlve)groups,and there was no significant difference in 5-year event-free survival(EFS)between the two groups(78.3%vs.83.3%,P=0.85).ATRA plus ATO and anthracycline-based chemotherapy achieved great outcome in newly diagnosed APL regardless of the FLT3-ITD mutation status.

LEUKOCYTOSIS AND RETINOIC ACID SYNDROME IN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA TREATED WITH ARSENIC TRIOXIDE

Objective To study the incidence of leukocytosis and retinoic acid (RA) syndrome in newly diagnosed and relapsed acute promyelocytic leukemia (APL) patients treated with arsenic trioxide (ATO). Methods Thirty patients with newly diagnosed or relapsed APL received ATO for remission induction at the dose of 10 mg/d. RA syndrome was defined when patient was with one or more of the following signs or symptoms: fever, dyspnea, serous cavity effusion, muscular pain, pulmonary infiltration, weight gain, or pulmonary infiltration on chest X-ray.Results Twenty-three (77%) patients achieved complete remission, mean time to remission was 37.1 days. Leukocytosis was observed in 14 (47%) patients, mean time to leukocytosis was 12.7 days, median baseline leukocyte count for patients with leukocytosis was 3.1×10 9/L, which was higher than that for patients who did not develop leukocytosis (2.6×10 9/L, z=-2.635, P=0.008). No other cytotoxic therapy was administered, and the leukocytosis resolved in all cases. The RA syndrome was observed in 9 (30%) patients, mean time to diagnose of RA syndrome was 13.9 days, median baseline leukocyte count for patients with RA syndrome was 3.6×10 9/L, which was higher than that for patients who did not develop RA syndrome (2.6×10 9/L, z=-1.909, P=0.046). No patient died of RA syndrome. Conclusion Leukocytosis and RA syndrome are associated with ATO and baseline leukocyte count respectively, and there is distinct link between leukocytosis and RA syndrome.

Rapid, accurate and serotype independent pipeline for in silico epitope mapping of SARS-CoV-2 antigens: a combined machine learning and Chou’s pseudo amino acid composition method

Here,a new integrated machine learning and Chou’s pseudo amino acid composition method has been proposed for in silico epitope mapping of severe acute respiratorysyndrome-like coronavirus antigens.For this,a training dataset including 266 linear B-cell epitopes,1,267 T-cell epitopes and 1,280 non-epitopes were prepared.The epitope sequences were then converted to numerical vectors using Chou’s pseudo amino acid composition method.The vectors were then introduced to the support vector machine,random forest,artificial neural network,and K-nearest neighbor algorithms for the classification process.The algorithm with the highest performance was selected for the epitope mapping procedure.Based on the obtained results,the random forest algorithm was the most accurate classifier with an accuracy of 0.934 followed by K-nearest neighbor,artificial neural network,and support vector machine respectively.Furthermore,the efficacies of predicted epitopes by the trained random forest algorithm were assessed through their antigenicity potential as well as affinity to human B cell receptor and MHC-I/II alleles using the VaxiJen score and molecular docking,respectively.It was also clear that the predicted epitopes especially the B-cell epitopes had high antigenicity potentials and good affinities to the protein targets.According to the results,the suggested method can be considered for developing specific epitope predictor software as well as an accelerator pipeline for designing serotype independent vaccine against the virus.

CYTOKINE SECRETION IN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA AFTER TREATMENT WITH ALLTRANS RETINOIC ACID

ABSRTACT Objective: To detect the modulation of cytokines production by acute promyelocytic leukemia (APL) cells before or after exposure to all-trans retinoic acid (ATRA). Methods: Diagnoses were performed according to the FAB cytological classification criteria and cytogenetic criteria. Bone marrow or blood samples from APL patients were collected in heparinized microfuge tube. Primary APL cells were separated and purified by traditional Ficoll-Hypaque density centrifugation and enriched after adherence to plastic surfaces. IL-1b, IL-6, IL-8, TNFa and G-CSF levels in the supernatants of cultured leukemia cells were estimated by ELISA method. NBT method was used to detect the differentiation of APL cells at the same time. Results: 96 h after exposure to ATRA at 10-6 M in vitro or 60 mg/day in vivo, APL cells showed a significant increase of IL-1b (P<0.05) and G-CSF (P<0.05) production, and a significant decrease of IL-6 (P<0.05) and IL-8 (P<0.05), however, there was no obvious variation of TNFa. On the other hand, the proliferation of APL cells in vitro was statistically correlated to the IL-1b secretion or G-CSF secretion. And the cell number ratio in patients with detectable IL-1b or G-CSF was higher than that without detectable IL-1b or G-CSF. Conclusion: IL-1b and G-CSF secretion may play an important role in the proliferation of APL cells after exposure to ATRA.

COMPARISON OF CLINICAL OBSERVATIONS BETWEEN PATIENTS WITH ACUTE PROMYELOCYTIC LEUKEMIA TREATED WITH ALL-TRANS RETINOIC ACID AND CHEMOTHERAPY

Clinical observations were retrospectively compared between 2 matched groups of patients with acute promyelocytic leukemia (APL) each 20. The first group were treated with chemotherapy, the other with all-tram retinoic acid (ATRA) alone at a dose of 45-60mg/M^2/d. The complete remission (CR) rate of ATRA group was significantly higher than that of chemotherapy (90% vs 55%). The time for obtaining CR as well as the duration of fever and hospitalization were shorter and the amount of blood transfused was less in the former than in the latter group. Seven cases were complicated by DIC and 4 died in the group of chemotherapy, while no case was by of DIC or death in the ATRA group. The mechanism was discussed. ATRA is an alternative effective drug for remission induction therapy in APL with high rate of CR.

Dehydroabietic acid chemosensitizes drug-resistant acute lymphoblastic leukemia cells by downregulating survivin expression

Objective:To explore the mechanism of drug resistance in acute lymphoblastic leukemia and the anti-tumor effect of combination therapy of dehydroabietic acid and vincristine against acute lymphoblastic leukemia cells.Methods:Acute lymphoblastic leukemia cells REH and CCRFCEM were employed to detect the anti-tumor effect of vincristine and doxorubicin on proliferation and apoptosis using EdU assay,human active caspase-3 Quantikine ELISA kit,and flow cytometry.Vincristine-resistant REH cells(REH-R),survivin knockdown and overexpressing REH cells were established to verify the role of survivin in drug resistance.Additionally,in vitro and in vivo assays were performed to determine the effect of dehydroabietic acid on the cytotoxicity of vincristine.Results:Vincristine and doxorubicin markedly suppressed proliferation and induced apoptosis of REH and CCRF-CEM cells.Survivin expression was upregulated in REH-R cells compared with REH cells.Knockdown of survivin expression obviously restored the sensitivity of REH-R cells to vincristine.Akt phosphorylation was also increased in REH-R cells compared to REH cells.In addition,LY294002,a PI3k/Akt pathway blocker,inhibited survivin expression and enhanced cytotoxicity of vincristine to REH-R cells.Dehydroabietic acid effectively reduced survivin expression in REH-R cells,thereby enhancing the therapeutic effect of vincristine on drug-resistant cells.Survivin overexpression markedly reduced the effect of dehydroabietic acid on enhancing the anti-proliferation and inducing apoptosis effect of vincristine.Moreover,the combination of dehydroabietic acid with vincristine significantly extended the survival rate in a mouse xenograft model of acute lymphoblastic leukemia,compared with vincristine treatment alone.Conclusions:Dehydroabietic acid may be used as a potential candidate for the treatment of acute lymphoblastic leukemia in combination with vincristine.

Clinical variations of serum levels of ferritin,folic acid and vitamin B_(12) in acute leukemia patients

Acute leukemia is one of the most common hematologic malignancies and its exact mechanism of development is unknown yet.In clinical,acute leukemia always accompany with abnormal iron balance.Ferritin,folic acid and vitamin B12 are important components of blood cells.In this study,we measured variations of serum levels of ferritin(SF),folic acid and vitamin B12 in the acute leukemia patients under different disease stages including first diagnosed stage,complete remission(CR) stage and not remission(NR) or relapse stage.It demonstrated that serum SF levels in patients at the first diagnosed stage and NR or relapse stage were significantly higher than the CR stage in acute myelocytic leukemia(AML) patients and acute lymphoblastic leukemia(ALL) patients(P<0.05).The serum folic acid levels in patients at the first diagnosed stage and NR or relapse stage were significantly lower than the CR stage in AML patients and ALL patients(P<0.001).Whereas,serum vitamin B12 levels in AML patients were significantly higher at the first diagnosed stage and NR or relapse stage than the CR stage(P<0.001).And it was significantly higher in ALL patients at the NR or relapse stage than at the first diagnosed stage and CR stage(P<0.05).There are obvious variations of serum levels of SF,folic acid and vitamin B12 in acute leukemia patients under different stages.Increased serum levels of SF and vitamin B12 and decreased levels of folic acid may correlate to the active degree of acute leukemia as well as tumor load.

Sweet syndrome and differentiation syndrome in a patient with acute promyelocytic leukemia

The differentiation syndrome is an inflammatory reaction with increased capillary permeability that occurs in up to 25% of patients with acute promyelocytic leukemia treated with all-trans retinoic acid. A 50-year-old man with acute promyelocytic leukemia underwent chemotherapy with idarubicin and all-trans retinoic acid. On day +21 the patient developed pruritic prepatelar papules as well as several 10 mm subcutaneous nodules in both thighs accompanied by persistent fever. On the day +25 the patient presented with bilateral pulmonary crackles, infiltrates in the right lower lobe and severe hypotension which required dopamine infusion. Biopsy of one of the thighs nodules was performed. A Sweet syndrome associated to a differentiation syndrome was suspected. All-trans retinoic acid therapy was discontinued and dexamethasone was administered. In 48 h the patient showed remission of the fever and the infiltrates and the skin lesions acquired a residual aspect. It is debatable whether these two syndromes are distinct entities with common mechanisms or whether they are poles of the same spectrum. Dermatologists and hematologists must be aware of these two syndromes and its pathophysiologic association.

Successful treatment of relapsed acute promyelocytic leukemia with arsenic trioxide in a hemodialysis-dependent patient: A case report

BACKGROUND Arsenic trioxide(ATO)is recommended for patients who do not achieve molecular remission or who have molecular or morphologic relapse.However,there are no guidelines for adjusting ATO dosage in patients with severe renal failure or on dialysis.Herein,we report the successful treatment of relapsed acute promyelocytic leukemia(APL)in a patient on hemodialysis with ATO single agent and review the cases in literature.CASE SUMMARY A 46-year-old woman who has been on hemodialysis to chronic glomerulonephritis for 15 years visited our hospital for pancytopenia.She had been seen for pancytopenia 3 years ago and had been diagnosed with APL.She also received chemotherapy for APL but unfortunately was lost to follow-up after her second consolidation chemotherapy.She was noted to have pancytopenia by her nephrologist during hemodialysis 1 mo ago.Bone marrow biopsy and reverse transcriptase-polymerase chain reaction(RT-PCR)tests revealed a diagnosis of relapsed APL.Treatment for relapsed APL with ATO single agent was started and she achieved molecular remission after administering 24 doses of ATO.Thus far,four consolidation therapies have been performed with the ATO single agent,and,to date,the molecular remission has been maintained as negative promyelocytic leukemia/retinoic acid receptor-αfusion gene as confirmed by RTPCR testing for two years.CONCLUSION This is a rare case of relapsed APL successfully treated with the single agent ATO in a patient on hemodialysis.

Myeloid sarcoma of the colon as initial presentation in acute promyelocytic leukemia:A case report and review of the literature

BACKGROUND Myeloid sarcoma(MS)rarely occurs in acute promyelocytic leukemia(APL)at onset,but it can develop in relapse cases,especially after APL treated with alltrans retinoic acid(ATRA).Therefore little is known about the clinical features and suitable treatment for APL related MS due to the rarity of the disease,although this may be different from the treatment and prognosis of MS in the relapse stage.To our best knowledge,this is the second case report of APL initial presentation as colon MS.CASE SUMMARY A 77-year-old woman complained of intermittent right lower abdominal pain,black stool,and difficult defecation for 2 mo.Physical examination showed diffuse tenderness during deep palpation and an anemic appearance.Laboratory findings showed positivity for fecal occult blood testing;white blood cell count:3.84×109/L;hemoglobin:105 g/L;platelet count:174×109/L;and negativity for tumor markers.Abdominal enhanced computed tomography showed a space occupying lesion in the colon(1.9 cm).Fibrocolonoscopy revealed a polypoid and ulcerated mass measuring 2.5 cm.The tumor was removed.To our surprise,MS was confirmed by immunohistochemistry.PML/RARαfusion gene was detected in colon specimens by fluorescent in situ hybridization and real-time reverse transcription polymerase chain reaction,which was consistent with the bone marrow.She was diagnosed as having APL related MS.A smooth and unobstructed intestinal wall was found by fibrocolonoscopy,and continuous molecular remission was confirmed in both the bone marrow and colon after four courses of ATRA+arsenic trioxide(ATO).ATRA+ATO showed a favorable therapeutic response for both APL and MS.CONCLUSION Early use of ATRA can benefit APL patients,regardless of whether MS is the first or recurrent manifestation.

Correlation between plasma hydrogen sulfide and homocysteine in patients with acute promyelocytic leukemia

Objective: To investigate the correlation between plasma hydrogen sulfide (H2S), homocysteine (Hcy), folic acid and vitamin B12 in patients with acute promyelocytic leukemia (APL) before and after treatment. Methods:A total of 26 hospitalized patients with APL were randomly selected as case group and 26 healthy persons as control group. The concentration of H2S, Hcy and folic acid in plasma of case group and control group were measured, respectively. The statistically significant difference was investigated by comparing the acute onset phase and clinical remission of case group with those of healthy control group. Results:The concentration of H2S and Hcy of plasma in patients of case group during acute onset phase significantly increased, and concentration of folic acid significantly decreased, and there were both statistically significant differences as compared with those during clinical remission and those of control group (P<0.01). The concentration of H2S and Hcy of plasma in patients of case group during clinical remission after treatment decreased, and concentration of folic acid increased. The result was close to that of healthy control group, and there was no statistically significant difference (P>0.05). The change in concentration of plasma H2S was positively correlated with that of Hcy and negatively correlated with that of folic acid in patients of case group before and after treatment. Conclusions:The increase of plasma H2S in patients with APL may be related to the changes in concentration of Hcy and folic acid.

Central nervous system recurrence in a patient treated for acute promyelocytic leukemia,resulting in sideroblastic anemia:A case report

BACKGROUND Previous cases that have been stated in this article have displayed that around 1%to 7%of patients that have been treated with chemotherapy for acute promyelocytic leukemia developed myelodysplastic syndrome or acute myeloid leukemia.One can see that’s why this case presentation of a 60-year-old man that had a good response to acute promyelocytic leukemia treatment,that later presented with a central nervous system recurrence of acute promyelocytic leukemia and acquired sideroblastic anemia(a form of myelodysplasia)from treatment is a unique case report.CASE SUMMARY The presence of central nervous system relapse in acute promyelocytic leukemia patients is very unlikely compared to recurring mainly in the bone marrow.It is also uncommon to be diagnosed with sideroblastic anemia(form of myelodysplastic syndrome)as a result from treatment for acute promyelocytic leukemia.This case report highlights the detection,treatment/maintenance with idarubicin,all-trans-retinoic-acid,arsenic trioxide,methotrexate,6-mercaptopurine,and ommaya reservoir intrathecal methotrexate administration in a patient that had central nervous system relapse of acute promyelocytic leukemia and acquired sideroblastic anemia.CONCLUSION In essence,first time relapse concerning the central nervous system in treated acute promyelocytic leukemia patients who had a good response to therapy is very uncommon.The acquirement of a myelodysplastic syndrome such as ringed sideroblastic anemia is also rare regarding this patient population.Although such cases are infrequent,this case report represents a unique insight of the detection,treatment,and maintenance of a 60-year-old man diagnosed with acute promyelocytic leukemia,resulting in the acquirement of sideroblastic anemia and central nervous system relapse.

脂肪酸代谢相关基因ACSL1在急性髓系白血病中的作用及潜在价值

目的:通过生物信息学数据分析脂肪酸代谢相关基因长链酯酰辅酶A合成酶1(ACSL1)在急性髓系白血病(AML)中的作用及潜在价值。方法:使用基因表达谱交互分析(GEPIA)数据库分析ACSL1基因在AML患者和健康对照人群中的表达水平。使用R包(以最优截断值10.73为高、低表达的分界)survminer绘制ACSL1高、低表达组的Kaplan-Meier生存曲线,分析ACSL1基因表达与AML患者生存率之间的相关性。使用R语言中timeROC包绘制ACSL1的受试者工作特征(ROC)曲线,探究ACSL1基因对正常和AML患者的诊断效率。通过单基因富集分析(GSEA),明确ACSL1基因的作用通路。采用Kaplan-Meier生存分析确定ACSL1表达水平与患者总生存期(OS)之间的关系。通过单因素和多因素Cox回归分析建立预后模型,确定ACSL1是否为AML的独立预后因素以及验证模型的预测效果。结果:ACSL1在AML患者中的表达水平较健康对照组明显升高(P<0.05),对AML具有诊断意义,且ACSL1高表达组患者生存较差,预后不良(P=0.045)。ROC曲线显示,ACSL1诊断AML患者1、2、3年生存时间的曲线下面积(AUC)均大于0.6,说明ACSL1预测准确率较高。富集分析表明,ACSL1主要通过脂肪酸降解、脂肪酸代谢等途径在AML发生和发展中发挥重要作用。单因素Cox分析显示年龄和ACSL1表达水平是影响AML患者总生存率的高风险因素(HR>1,P<0.05),多因素Cox分析显示年龄、染色体异常分数、基因突变分数是AML影响患者预后的独立因素(P<0.05)。结论:脂肪酸代谢相关基因ACSL1在AML中高表达,在多个致癌通路和脂肪酸代谢通路中富集,与不良预后密切相关,可作为AML的潜在治疗靶点和预后生物标志物。

全反式维甲酸联合小剂量阿糖胞苷对急性髓系白血病细胞磷脂酰肌醇3激酶/蛋白质丝氨酸苏氨酸激酶信号通路的作用机制研究

目的:探讨全反式维甲酸(ATRA)联合小剂量阿糖胞苷(Ara-C)对急性髓系白血病细胞磷脂酰肌醇3激酶(PI3K)/蛋白质丝氨酸苏氨酸激酶(AKT)信号通路的作用机制。方法:选取人急性髓系白血病细胞HL-60,分为空白对照组(未经任何处理的HL-60细胞)、Ara-C组(加入0.5μmol/LAra-C)、ATRA组(加入2μmol/LATRA)、ATRA+Ara-C组(加入2μmol/LATRA和0.5μmol/LAra-C),继续培养24、48、72h,采用CCK8检测HL-60细胞活力,AnnexinV双染法检测HL-60细胞凋亡,qRT-PCR检测PI3K、AKT-mRNA表达,Westernblot检测PI3K/AKT信号通路相关蛋白表达,并进行细胞形态学观察。结果:空白对照组HL-60细胞活力高于Ara-C+ATRA组、Ara-C组、ATRA组,Ara-C组、ATRA组HL-60细胞活力高于Ara-C+ATRA组(均P<0.05)。Ara-C+ATRA组HL-60细胞凋亡率高于Ara-C组、ATRA组,Ara-C组、ATRA组HL-60细胞凋亡率高于空白对照组(均P<0.05)。HL-60细胞胞体多呈圆形,可见瘤状突起,胞核多为类圆形,Ara-C组、ATRA组染色质凝聚,颜色变深,部分胞核变小,Ara-C+ATRA组染色质凝聚,颜色变深,可见核固缩、核碎裂。空白对照组HL-60细胞PI3K、AKTmRNA表达高于Ara-C组、ATRA组,Ara-C组、ATRA组HL-60细胞PI3K、AKTmRNA表达高于Ara-C+ATRA组(均P<0.05)。空白对照组HL-60细胞P-PI3K、P-AKT蛋白表达高于Ara-C组、ATRA组,Ara-C组、ATRA组HL-60细胞P-PI3K、P-AKT蛋白表达高于Ara-C+ATRA组(均P<0.05)。结论:Ara-C+ATRA能通过抑制PI3K/AKT信号通路激活,促进HL-60细胞凋亡。

阿魏酸通过调节PTEN/PI3K/AKT信号通路抑制急性T淋巴细胞白血病进展

目的探究阿魏酸是否可通过调控PTEN/PI3K/AKT信号通路在体内外抑制急性T淋巴细胞白血病进展。方法将急性T淋巴细胞白血病Jurkat细胞分为对照组、阿魏酸处理组和LY294002处理组进行体外实验,对照组正常培养;阿魏酸处理组分别给予不同浓度(1.25、2.5、5、10、20、40、80、160µmol/L)阿魏酸,采用CCK-8法检测细胞增殖能力,筛选实验浓度;LY294002处理组给予50µmol/L PI3K/AKT抑制剂LY294002,采用克隆形成实验、流式细胞术、Transwell实验检测细胞增殖、凋亡、侵袭情况,采用Western blot检测核蛋白Ki67、增殖细胞核抗原(PCNA)、cleaved caspase-3、cleaved caspase-9、E-cadherin、N-cadherin、Vimentin、PTEN、p-PI3K、PI3K、p-AKT和AKT蛋白相对表达量。使用30只雄性BALB/c裸鼠建立移植瘤裸鼠模型,平均分为正常组和阿魏酸处理组进行体内实验,正常组接种Jurkat细胞后以生理盐水灌胃,阿魏酸处理组接种Jurkat细胞后以75 mg/kg阿魏酸灌胃,比较移植瘤质量和体积变化,并检测肿瘤组织中Ki67、cleaved caspase-3/caspase-3、E-cadherin、N-cadherin、PTEN、p-PI3K、PI3K、p-AKT和AKT水平。结果体外实验中,与对照组比较,5、10、20µmol/L阿魏酸处理组和LY294002处理组细胞克隆形成率、细胞侵袭数、Ki67、PCNA、N-cadherin、Vimentin、p-PI3K/PI3K、p-AKT/AKT明显降低/减少(P<0.05),细胞凋亡率、cleaved caspase-3/caspase-3、cleaved caspase-9/caspase-9、E-cadherin、PTEN明显升高(P<0.05)。体内实验中,与正常组比较,阿魏酸处理组裸鼠肿瘤质量减轻,肿瘤体积减小,肿瘤组织中Ki67、N-cadherin、p-PI3K/PI3K、p-AKT/AKT明显降低,cleaved caspase-3/caspase-3、E-cadherin、PTEN明显升高,差异均有统计学意义(P<0.05)。结论阿魏酸在体内外均可抑制急性T淋巴细胞白血病Jurkat细胞的增殖及侵袭,并诱导细胞凋亡,其作用机制可能与调控PTEN/PI3K/AKT信号通路有关。

新藤黄酸对急性淋巴细胞性白血病的调控机制

目的探究新藤黄酸对急性淋巴细胞性白血病细胞Nalm-6的增殖、迁移、侵袭的影响及作用机制。方法使用不同浓度的新藤黄酸处理Nalm-6细胞,通过MTT实验、软琼脂克隆形成实验、transwell迁移实验与transwell侵袭实验来检测新藤黄酸对Nalm-6细胞增殖、迁移、侵袭的影响。通过凋亡坏死检测试剂盒检测Nalm-6细胞的凋亡情况,通过Western blot实验检测Nalm-6细胞中c-Myc、P21蛋白表达情况。结果新藤黄酸可呈剂量依赖性抑制Nalm-6细胞的增殖、克隆形成、迁移与侵袭,导致Nalm-6细胞凋亡,下调c-Myc表达,上调P21表达。结论新藤黄酸可通过调控c-Myc和P21抑制Nalm-6,有望为急性淋巴细胞性白血病提供新的潜在治疗选择。

Pathophysiology, clinical features and radiological findings of differentiation syndrome/all-trans-retinoic acid syndrome

In acute promyelocytic leukemia, differentiation thera-py based on all-trans-retinoic acid can be complicated by the development of a differentiation syndrome(DS). DS is a life-threatening complication, characterized by respiratory distress, unexplained fever, weight gain, interstitial lung infiltrates, pleural or pericardial effusions, hypotension and acute renal failure. The diagnosis of DS is made on clinical grounds and has proven to be difficult, because none of the symptoms is pathognomonic for the syndrome without any definitive diagnostic criteria. As DS can have subtle signs and symptoms at presentation but progress rapidly, end-stage DS clinical picture resembles the acute respiratory distress syndrome with extremely poor prognosis; so it is of absolute importance to be conscious of these complications and initiate therapy as soon as it was suspected. The radiologic appearance resembles the typical features of cardiogenic pulmonary edema. Diagnosis of DS remains a great skill for radiologists and haematologist but it is of an utmost importance the cooperation in suspect DS, detect the early signs of DS, examine the patients' behaviour and rapidly detect the complications.

Effects of Gambogic Acid on the Regulation of Nucleoporin Nup88 in U937 Cells

In order to investigate the anti-leukemia effects of gambogic acid （GA） and its relation to the regulation of nucleoporin Nup88 in U937 cells in vitro, the inhibitory effect of GA on the growth of U937 cells was examined by using MTT assay. Apoptosis was detected by Annexin-V FITC/PI double-labeled cytometry. Cell cycle regulation was studied by propidium iodide method. Both flow cytometry （FCM） and RT-PCR were employed to assess the expression of Nup88, and the localization of Nup88 was determined by confocal microscopy. The results indicated that GA had strong inhibitory effect on cell proliferation and apoptosis induction activity in U937 cells in vitro in a time-and dose-dependent manner. The 24-h IC50 value was （1.019±0.134） mg/L. Moreover, GA induced arrest of U937 cells in G0/G1 phase. Over-expression of Nup88 was found in U937 cells, whereas GA could significantly down-regulate both the protein and mRNA levels of Nup88. Nup88 was diffusely distributed between nucleus and cytoplasm and was located at the cytoplasmic side of nuclear rim, and occasionally in cytoplasm. It is suggested that GA exerts its anti-leukemia effects by regulating the expression and distribution of nucleoporin Nup88. It promises to be new agent for the treatment of acute leukemia.

Loss of LAT1 sex-dependently delays recovery after caerulein-induced acute pancreatitis

BACKGROUND The expression of amino acid transporters is known to vary during acute pancreatitis(AP)except for LAT1(slc7a5),the expression of which remains stable.LAT1 supports cell growth by importing leucine and thereby stimulates mammalian target of rapamycin(mTOR)activity,a phenomenon often observed in cancer cells.The mechanisms by which LAT1 influences physiological and pathophysiological processes and affects disease progression in the pancreas are not yet known.AIM To evaluate the role of LAT1 in the development of and recovery from AP.METHODS AP was induced with caerulein(cae)injections in female and male mice expressing LAT1 or after its knockout(LAT1 Cre/LoxP).The development of the initial AP injury and its recovery were followed for seven days after cae injections by daily measuring body weight,assessing microscopical tissue architecture,mRNA and protein expression,protein synthesis,and enzyme activity levels,as well as by testing the recruitment of immune cells by FACS and ELISA.RESULTS The initial injury,evaluated by measurements of plasma amylase,lipase,and trypsin activity,as well as the gene expression of dedifferentiation markers,did not differ between the groups.However,early metabolic adaptations that support regeneration at later stages were blunted in LAT1 knockout mice.Especially in females,we observed less mTOR reactivation and dysfunctional autophagy.The later regeneration phase was clearly delayed in female LAT1 knockout mice,which did not regain normal expression of the pancreas-specific differentiation markers recombining binding protein suppressor of hairless-like protein(rbpjl)and basic helixloop-helix family member A15(mist1).Amylase mRNA and protein levels remained lower,and,strikingly,female LAT1 knockout mice presented signs of fibrosis lasting until day seven.In contrast,pancreas morphology had returned to normal in wild-type littermates.CONCLUSION LAT1 supports the regeneration of acinar cells after AP.Female mice lacking LAT1 exhibited more pronounced alterations than male mice,indicating a sexual dimorphism of amino acid metabolism.