PARTIAL PURIFICATION AND CHARACTERIZATION OF AN AUTOCRINE T SUPPRESSOR FACTOR FROM MURINE LEUKEMIA

The leukemia-associated autoinhibitor (LAI-615) derived from murine leukemia L7811 has been investigated intensively in our laboratory. In the following experiments, the partial purification of LA I-615 has been carried out in addition to the observation of phenotype variations of L7811 leuke-mic cells. The factor was purified over 1306-fold by sequential fractionation with Sephadex G-150 gel filtration, DEAE-cellulose ion exchange chromato-graphy, and Mono Q-fast protein liquid chromato-graphy. The molecular weight of LAI-615 was 68,000 as estimated by gel filtration. LAI-615 was a protein but not glycosylated, and it was suggested LAI-615 be secreted in an autocrine manner. Im-munocytochemical staining showed that the expression of Lyt2 phenotype of L7811 leukemic cells was often coincident with the secretion of LAI-615. Moreover, the physicochemical characteristics of LAI-615 was similar to that of T suppressor factor. Thus it is concluded that LAI-615 may be one of TsF-like factors.

Inactivated Sendai Virus Induces Apoptosis in Murine Melanoma Cells by IGF-1R Down-regulation

The mortality of cancer patients has considerably improved due to progress in surgery, chemotherapy and radiotherapy. However, some types of cancers, such as melanoma, remain refractory to conventional strategies. Although melanoma accounts for only 4% of all dermatological malignancies, it is responsible for 80% of mortalities from skin tumors[11. The reported survival rate of melanoma over 5 years is not yet encouraging due to its chemo-resistance and rapid metastasis. Therefore, it is necessary to develop new drugs with potent activity and weak side-effect against melanoma.

Evaluation of antiviral activities of Houttuynia cordata Thunb.extract,quercetin,quercetrin and cinanserin on murine coronavirus and dengue virus infection

Objective:To evaluate the in vitro activities of the ethyl acetate(EA) fraction of Houttuynia cordata(H.cordata) Thunb.(Saururaceae) and three of its constituent flavonoids(quercetin.quercitrin and rutin) against murine coronavirus and dengue virus(DENV).Methods:The antiviral activities of various concentrations of the EA fraction of H.cordata and flavonoids were assessed using virus neutralization tests against mouse hepatitis virus(MHV) and DENV type 2(DENV-2).Cinanserin hydrochloride was also tested against MHV.The EA fraction of H.cordata was tested for acute oral toxicity in C57BL/6 mice.Results:The EA fraction of H.cordata inhibited viral infectivity up to 6 d.Cinanserin hydrochloride was able to inhibit MHV for only 2 d.The 50%inhibitory concentrations(IC_(50)) of the EA fraction of H.cordata added before the viral adsorption stage were 0.98 μg/mL for MHV and 7.50 μg/mL for DENV-2with absence of cytotoxicity.The mice fed with the EA fraction up to 2 000 mg/kg did not induce any signs of acute toxicity,with normal histological features of major organs.Certain flavonoids exhibited comparatively weaker antiviral activity,notably quercetin which could inhibit both MHV and DENV-2.This was followed by quercitrin which could inhibit DENV-2but not MHV,whereas rutin did not exert any inhibitory effect on either virus.When quercetin was combined with quercitrin,enhancement of anti-DENV-2 activity and reduced cytotoxicity were observed.However,the synergistic efficacy of the flavonoid combination was still less than that of the EA fraction.Conclusions:The compounds in H.cordata contribute to the superior antiviral efficacy of the EA fraction which lacked cytotoxicity in vitro and acute toxicity in vim.H.cordata has much potential for the development of antiviral agents against coronavirus and dengue infections.

Fibrinogen-like protein 2 fibroleukin expression and its correlation with disease progression in murine hepatitis virus type 3-induced fulminant hepatitis and in patients with severe viral hepatitis B

AIM： To evaluate the expression of fibrinogenlike protein 2 （fgl2） and its correlation with disease progression in both mice and patients with severe viral hepatitis. METHODS： Balb/cJ or A/J mice were infected intraperitoneally （ip） with 100 PFU of murine hepatitis virus type 3 （MHV-3）, liver and serum were harvested at 24, 48, and 72 h post infection for further use. Liver tissues were obtained from 23 patients with severe acute chronic （AOC） hepatitis B and 13 patients with mild chronic hepatitis B. Fourteen patients with mild chronic hepatitis B with cirrhosis and 4 liver donors served as normal controls. In addition, peripheral blood mononuciear cells （PBMC） were isolated from 30 patients （unpaired） with severe AOC hepatitis B and 10 healthy volunteers as controls. Procoagulant activity representing functional prothrombinase activity in PBMC and white blood cells was also assayed. A polyclonal antibody against fgl2 was used to detect the expression of both mouse and human fgl2 protein in liver samples as well as in PBMC by immunohistochemistry staining in a separate set of studies. Alanine aminotransferase （ALT） and total bilirubin （TBil） in serum were measured to assess the severity of liver injury.RESULTS： Histological changes were found in liver sections 12-24 h post MHV-3 infection in Balb/cJ mice. In association with changes in liver histology, marked elevations in serum ALT and TBil were observed. House fgl2 （mfgl2） protein was detected in the endothelium of intrahepatic veins and hepatic sinusoids within the liver 24 h after MHV-3 infection. Liver tissues from the patients with severe AOC hepatitis B had classical pathological features of acute necroinflammation. Human fgl2 （hfgl2） was detected in 21 of 23 patients （91.30%） with severe AOC hepatitis B, while only 1 of 13 patients （7.69%） with mild chronic hepatitis B and cirrhosis had hfgl2 mRNA or protein expression. Twenty-eight of thirty patients （93.33%） with severe AOC hepatitis B and 1 of 10 with mild chronic hepatitis B had detectable hfgl2 expression in PBMC. No hfgl2 expression was found either in the liver tissue or in the PBMC from normal donors. There was a positive correlation between hfgl2 expression and the severity of the liver disease as indicated by the levels of TBil. PCA significantly increased in PBMC in patients with severe AOC hepatitis B. CONCLUSION： The molecular and cellular results reported here in both mice and patients with severe viral hepatitis suggest that virus-induced hfgl2 prothrombinase/fibroleukin expression and the coagulation activity associated with the encoded fgl2 protein play a pivotal role in initiating severe hepatitis. The measurement of hfgl2/fibroleukin expression in PBMC may serve as a useful marker to monitor the severity of AOC hepatitis B and a target for therapeutic intervention.

CD69+NK Cells Contribute to the Murine Hepatitis Virus Strain 3-Induced Murine Hepatitis

Summary： The role of hepatic CD69＋ natural killer （NK） cells in virus-induced severe liver injury and subsequent hepatic failure is not well defined. In this study, a mouse model of fulminant liver failure （FHF） induced by murine hepatitis virus strain 3 （MHV-3） was used to study the role of hepatic CD69＋NK cells in the development of FHF. The CD69 expression in NK cells in the liver, spleen, bone marrow and peripheral blood was detected by using flow cytometry. The correlation between the CD69 level in hepatic NK cells and liver injury was studied. The functional marker （CD107a）, and activating and inhibitory receptor （NKG2D and NKG2A） expressed on CD69＋NK cells and CD69-NK cells were detected by using flow cytometry. Pro-inflammatory cytokines （IL-9, IFN-y and TNF-a） were also examined by using intracellular staining. After MHV-3 infection, the number of CD69＋NK cells in the liver of BALB/cJ mice was increased markedly and peaked at 72 h post-infection. Similar changes were also observed in the spleen, bone marrow and peripheral blood. Meanwhile, the CD69 expression in hepatic NK cells was highly correlated with the serum level of ALT and AST. The expression of CD107a and NKG2D, as well as the production of TNF-a, IFN-7 and IL-9 in hepatic CD69＋NK cells was all significantly up-regulated during 48-72 h post-infection. In contrast, the NKG2A expression was increased in hepatic CD69-NK cells but not in CD69＋NK cells. These results suggested that hepatic CD69＋NK cells play a pivotal role in the pathogenesis of FHF by enhancing degranulation and cytotoxic ability of NK cells and increasing the production of pro-inflammatory cytokines.

Murine models based on acute myeloid leukemia-initiating stem cells xenografting

Acute myeloid leukemia(AML) is an aggressive malignant disease defined by abnormal expansion of myeloid blasts. Despite recent advances in understanding AML pathogenesis and identifying their molecular subtypes based on somatic mutations, AML is still characterized by poor outcomes, with a 5-year survival rate of only 30%-40%, the majority of the patients dying due to AML relapse. Leukemia stem cells(LSC) are considered to be at the root of chemotherapeutic resistance and AML relapse. Although numerous studies have tried to better characterize LSCs in terms of surface and molecular markers, a specific marker of LSC has not been found, and still the most universally accepted phenotypic signature remains the surface antigens CD34+CD38- that is shared with normal hematopoietic stem cells. Animal models provides the means to investigate the factors responsible for leukemic transformation, the intrinsic differences between secondary post-myeloproliferative neoplasm AML and de novo AML, especially the signaling pathways involved in inflammation and hematopoiesis. However, AML proved to be one of the hematological malignancies that is difficult to engraft even in the most immunodeficient mice strains, and numerous ongoing attempts are focused to develop "humanized mice" that can support the engraftment of LSC. This present review is aiming to in-troduce the field of AML pathogenesis and the concept of LSC, to present the current knowledge on leukemic blasts surface markers and recent attempts to develop best AML animal models.

B lymphoma Moloney murine leukemia virus insertion region 1: An oncogenic mediator in prostate cancer

B lymphoma Moloney murine leukemia virus insertion region 1 (BMI1), a core member of polycomb repressive complex 1 (PRC1), has been intensely investigated in the field of cancer epigenetics for decades. Widely known as a critical regulator in cellular physiology, BMI1 is essential in self-renewal and differentiation in different lineages of stem cells. BMI1 also plays a significant role in cancer etiology for its involvement in pathological progress such as epithelial–mesenchymal transition (EMT) and cancer stem cell maintenance, propagation, and differentiation. Importantly, overexpression of BMI1 is predictive for drug resistance, tumor recurrence, and eventual therapy failure of various cancer subtypes, which renders the pharmacological targeting at BMI1 as a novel and promising therapeutic approach. The study on prostate cancer, a prevalent hormone-related cancer among men, has promoted enormous research advancements in cancer genetics and epigenetics. This review summarizes the role of BMI1 as an oncogenic and epigenetic regulator in tumor initiation, progression, and relapse of prostate cancer.

Establishment of Murine Infection Models with Biological Clones of Dengue Viruses Derived from a Single Clinical Viral Isolate

Dengue virus(DENV)is a single-stranded RNA virus transmitted by mosquitoes in tropical and subtropical regions.It causes dengue fever,dengue hemorrhagic fever and dengue shock syndrome in patients.Each year,390 million people are estimated to be infected by four serotypes of dengue virus,creating a great burden on global public health and local economy.So far,no antiviral drug is available for dengue disease,and the newly licensed vaccine is far from satisfactory.One large obstacle for dengue vaccine and drug development is the lack of suitable small animal models.Although some DENV infection models have been developed,only a small number of viral strains can infect immunodeficient mice.In this study,with biologically cloned viruses from a single clinical isolate,we have established two mouse models of DENV infection,one is severe lethal infection in immunocompromised mice,and the other resembles self-limited disease manifestations in Balb/c mice with transient blockage of type I IFN responses.This study not only offers new small animal models of dengue viral infection,but also provides new viral variants for further investigations on dengue viral pathogenesis.

环状RNA hsa_circ_0085576调控微小RNA-498/B细胞特异性莫洛尼鼠白血病病毒整合位点1轴对口腔鳞状细胞癌细胞迁移和侵袭的影响

目的探究环状RNA hsa_circ_0085576对口腔鳞状细胞癌(OSCC)细胞迁移和侵袭的影响及其分子机制。方法使用实时荧光定量聚合酶链反应(qRT-PCR)和蛋白印迹法检测OSCC细胞中hsa_circ_0085576、微小RNA-498(miR-498)以及B细胞特异性莫洛尼鼠白血病病毒整合位点1(BMI-1)的表达水平。使用CCK-8、划痕实验、Transwell实验以及qRT-PCR、蛋白印迹法分别检测SCC-15细胞增殖活力、迁移及侵袭能力以及相关基因和蛋白的相对表达量。结果OSCC细胞中hsa_circ_0085576与BMI-1表达上调,miR-498表达下调(P<0.05)。下调hsa_circ_0085576表达或过表达miR-498后SCC-15细胞的增殖活性、划痕愈合率、侵袭细胞数目以及细胞周期蛋白D1、波形蛋白表达水平下调,miR-498和E-钙黏蛋白表达水平上调(P<0.05);抑制miR-498表达可减弱下调hsa_circ_0085576表达对OSCC细胞增殖、迁移及侵袭的抑制作用;上调BMI-1表达可减弱过表达miR-498对OSCC细胞增殖、迁移及侵袭的抑制作用。结论下调hsa_circ_0085576表达可通过激活miR-498/BMI-1轴抑制OSCC细胞增殖、迁移及侵袭。

血清miR-340-5p、Bmi-1与老年急性脑梗死后血管性认知障碍的相关性研究

目的探讨血清微小RNA-340-5p(miR-340-5p)、B细胞特异性Moloney小鼠白血病病毒整合位点1(Bmi-1)与老年急性脑梗死后血管性认知障碍(VCI)的相关性。方法选取2021年3月至2023年2月就诊的103例老年急性脑梗死患者作为研究对象,根据MoCA评分将患者分为VCI组(n=60)和无VCI组(n=43)。比较2组患者的一般资料;采用实时荧光定量PCR(RT-qPCR)法检测2组血清中miR-340-5p、Bmi-1的表达情况;ENCORI预测miR-340-5p与Bmi-1的靶向关系;Pearson法分析VCI患者血清miR-340-5p与Bmi-1表达水平相关性;Spearman相关分析血清miR-340-5p、Bmi-1水平与MoCA评分的相关性;Logistic回归分析老年急性脑梗死患者发生VCI的影响因素;受试者工作特征(ROC)曲线分析血清miR-340-5p、Bmi-1水平对老年急性脑梗死患者发生VCI的诊断价值。结果VCI组患者吸烟史、既往脑梗病史占比显著高于无VCI组(P<0.05),MoCA评分显著低于无VCI组,差异有统计学意义(P<0.05);与无VCI组相比,VCI组miR-340-5p表达水平均明显降低(P<0.05),Bmi-1表达水平明显升高,差异有统计学意义(P<0.05);ENCORI网站预测结果显示,miR-340-5p与Bmi-1可能存在靶向关系;且VCI组患者血清miR-340-5p表达水平与Bmi-1呈负相关,血清miR-340-5p表达与MoCA评分呈正相关,Bmi-1表达与MoCA评分呈负相关(P<0.05);Logistics回归分析结果显示,MoCA评分、miR-340-5p是影响老年急性脑梗死患者发生VCI的保护因素(P<0.05),吸烟史、既往脑梗死病史、Bmi-1是影响老年急性脑梗死患者发生VCI的危险因素(P<0.05);ROC曲线分析结果显示,血清miR-340-5p、Bmi-1表达水平(AUC=0.851、0.886)对老年急性脑梗死后VCI有良好的诊断效果,且二者联合诊断效果更佳(AUC=0.947,Z二者联合-miR-340-5p=3.018、P=0.003,Z二者联合-Bmi-1=2.636,P=0.008)。结论老年急性脑梗死后VCI患者血清,miR-340-5p表达下调,Bmi-1表达上调,二者表达水平与老年急性脑梗死患者发生VCI过程密切相关。

Chronic myeloid leukemia-from the Philadelphia chromosome to specific target drugs:A literature review

Chronic myeloid leukemia(CML)is a myeloproliferative neoplasm and was the first neoplastic disease associated with a well-defined genotypic anomaly―the presence of the Philadelphia chromosome.The advances in cytogenetic and molecular assays are of great importance to the diagnosis,prognosis,treatment,and monitoring of CML.The discovery of the breakpoint cluster region(BCR)-Abelson murine leukemia(ABL)1 fusion oncogene has revolutionized the treatment of CML patients by allowing the development of targeted drugs that inhibit the tyrosine kinase activity of the BCR-ABL oncoprotein.Tyrosine kinase inhibitors(known as TKIs)are the standard therapy for CML and greatly increase the survival rates,despite adverse effects and the odds of residual disease after discontinuation of treatment.As therapeutic alternatives,the subsequent TKIs lead to faster and deeper molecular remissions;however,with the emergence of resistance to these drugs,immunotherapy appears as an alternative,which may have a cure potential in these patients.Against this background,this article aims at providing an overview on CML clinical management and a summary on the main targeted drugs available in that context.

3D腹腔镜结肠癌根治手术疗效分析及预后评价

目的探讨3D腹腔镜结肠癌根治手术疗效及安全性,分析Bmi-1和CDX-2表达与结肠癌临床病理特征及预后的关系。方法对比分析腹腔镜手术与开腹手术2组切口总长度、手术时间、术中失血量、清扫淋巴结数目、术后12 h疼痛评分、肠功能恢复时间及术后平均住院日7项指标;采用免疫组化EliVision TM plus两步法检测结肠癌组织Bmi-1和CDX-2的表达,分析其与患者年龄、瘤体大小、分化等级、淋巴结转移及5年内复发转移5项临床病理特征的相关性。结果腹腔镜组与开腹组比较,手术时间、清除淋巴结数目无显著差异,但切口总长度小,手术失血量少,术后12 h疼痛评分低,肠功能恢复快,术后平均住院日短。结肠癌组织Bmi-1和CDX-2阳性率分别为79.1%和64.2%。Bmi-1表达与年龄、瘤体大小、分化等级无关,在有淋巴结转移、5年内复发转移患者中其阳性率显著高于无淋巴结转移、5年内无复发转移者;CDX-2表达与年龄、瘤体大小无关,在低分化等级、有淋巴结转移、5年内复发转移患者中其阳性率显著低于(高+中)分化、无淋巴结转移、5年内无复发转移者。Bmi-1和CDX-2表达呈负相关性。结论3D腹腔镜结肠癌手术具有满意的根治效果和安全性,癌组织Bmi-1高表达、CDX-2低表达预示术后易发生复发转移,患者预后不良。

Hepatitis B reactivation in chronic myeloid leukemia patients receiving tyrosine kinase inhibitor

Hepatitis B virus(HBV) reactivation is a well-recognized complication in patients with chronic HBV infection receiving cytotoxic or immunosuppressive chemotherapy.Imatinib mesylate and nilotinib are selective Bcr/Abl tyrosine kinase inhibitors,which are now widely used in the treatment of patients with chronic myeloid leukemia.Although HBV reactivation induced by imatinib mesylate has been reported,nilotinib-related HBV reactivation has not been reported in the English literature.We report here 2 cases of HBV reactivation in chronic myeloid leukemia patients receiving imatinib mesylate and a novel case of nilotinib related HBV reactivation.

Enzyme-Linked Immunosorbent Assays Using the Recombinant gp51 and p24 of Bovine Leukemia Virus for Immunodetection of the Disease

Enzyme-linked immunosorbent assay (ELISA) is often used to test bovine leukemia virus (BLV) infection. However, commercially available kits test in South America detect only antibodies against the gp51 protein. With the aim to improve the sensitivity of the test, we developed here a two-step indirect dual ELISA test that included both proteins p24 and gp51, expressed and produced in E. coli and baculovirus expression system respectively. Two hundred ten BLV sera, stated as double positive or double negative by the combination of commercial agar gel immunodiffusion (AGID) assay and a gp51-ELISA test, were tested with our in house dual rp24/rgp51 ELISA. Firstly, we checked the purified, optimized and standardized proteins as antigen by the checkerboard technique, and set up our in house ELISA test. The concordance correlation coefficient (CCC) and coefficient of variation (CV) intraplate repeatability levels were within the values established by the international standards. The statistical analysis demonstrated the value of sera correctly ranked highest (93.48%), and for 0.3 cutoff, the sensitivity was 95.65% and the specificity 91.30%. In conclusion, the rp24/rgp51 ELISA developed and standardized here demonstrated to have good analytical characteristics to be considered for screening of BLV.

Aggressive natural killer cell leukemia with skin manifestation associated with hemophagocytic lymphohistiocytosis:A case report

BACKGROUND Aggressive natural killer cell leukemia(ANKL)is a rare natural killer cell neoplasm characterized by systemic infiltration of Epstein–Barr virus and rapidly progressive clinical course.ANKL can be accompanied with hemophagocytic lymphohistiocytosis(HLH).Here,we report a case of ANKL with rare skin lesions as an earlier manifestation,accompanied with HLH,and review the literature in terms of etiology,clinical manifestation,diagnosis and treatment.CASE SUMMARY A 30-year-old woman from Northwest China presented with the clinical characteristics of jaundice,fever,erythema,splenomegaly,progressive hemocytopenia,liver failure,quantities of abnormal cells in bone marrow,and associated HLH.The immunophenotypes of abnormal cells were positive for CD2,cCD3,CD7,CD56,CD38 and negative for sCD3,CD8 and CD117.The diagnosis of ANKL complicated with HLH was confirmed.Following the initial diagnosis and supplementary treatment,the patient received chemotherapy with VDLP regimen(vincristine,daunorubicin,L-asparaginase and prednisone).However,the patient had severe adverse reactions and complication such as severe hematochezia,neutropenia,and multiple organ dysfunction syndrome,and died a few days later.CONCLUSION This is the first reported case of ANKL with rare skin lesions as an earlier manifestation and associated with HLH.

Bovine Leukemia Virus Gene Segment Detected in Human Breast Tissue

Background: Bovine Leukemia Virus (BLV) is known by infections in bovine cattle and produce, in 30% of infected animals, persistent lymphocytosis significantly impacts the beef industry. It has been proposed that this virus could be transmitted to humans and be present in cases of breast cancer. Aim: to determine the presence of 380 bp of gag gene segment of BLV in paraffin-embedded breast tissue. Study Design: Control-case study. Methodology: 106 tissue samples were collected. 53 were cancer positive samples and 53 were negative samples for this pathology. After dewaxing tissues, DNA was extracted, amplified and sequenced. Phylogenetic analysis was done in order to verify BLV gene segment, presence and origin. Results: 43 samples were positive (40.5%) for BLV segment. In the case group this segment was found in 35.8% of the samples and in the control group, BLV presented in 45.2% of the samples. Phylogenetic analysis confirmed BLV presence and had shown a high homology between amplified gene sequences obtained from human breast tissues and those coming from bovine cattle with leukosis reported by GenBank. Conclusion: The presence of BLV genes in humans and its location in breast tissue can be confirmed, however, it should be clarified as a possible promoter of malignancy processes on this tissue.

ESTABLISHMENT OF A CELL LINE INFECTED WITH SRS MOUSE LEUKEMIA VIRUS AND ITS BIOLOGICAL CHARACTERISTICS

NIH/3T3 cells were infected with a cell-free extract from the mouse SRS ascltic tumor and propagated at vitro. Experimental results showed that type A and type C virus particles were observed in the cytoplasm of infected NIH/ 3T3 cells by electron-microscopy, X-C assay and reverse transcriptase were both positive. Free proviral-DN A of the leukemia vims was found in the infected NIH/3T3 cell by Southern blot hybridization.Morphologically, the NIH/3T3 cells infected in vitro appeared spherical and formed monolayer cell colonies of various sizes after 24 - 48 hours. When the cultured cells were Inoculated into nude mice (BALB/ c, nu nu ) subcutaneously, flbrosarcoma was Induced, 100%. Inoculation of the cell-free extract of the same cultured cells into Inbred SW-1 newborn mice, resulted in the production of lymphocytic leukemia and lymphoma in 52. 3% within 191 days.

A novel mouse model of adult T-cell leukemia cell invasion into the spinal cord

Adult T-cell leukemia( ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type I infection, and 10%-25% of patients show central nervous system( CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg-Prkdc~ (scid) Il2 rg ^(tm1Wjl)/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly(I.M.) at 5 weeks of age, 8(80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously(S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV-1-specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV-1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement.

Cerebral Localization of Chronic Lymphocytic Leukemia Simulating Progressive Multifocal Leukoencephalopathy: The Lessons from a Case

Background: Central neurological involvement is the most frequent extra hematological manifestation of chronic lymphocytic leukemia;it is multifactorial and rarely due to a cerebral localization of the disease. We report a case of cerebral localization of chronic lymphoid leukemia whose clinical and radiological aspects were very suggestive of progressive multifocal leukoencephalopathy. Case Presentation: A 65-year-old patient who was HIV-negative (human immunodeficiency virus), had consulted for bilateral axillary, cervical and inguinal lymphadenopathy associated with major asthenia and hyper lymphocytosis (lymphocyte count was 11 giga/l). Chronic lymphocyticleukemia with TP53 mutation was diagnosed and treatment with Ibrutinib 420 mg/day was initiated. After 2 months of treatment, the evolution was marked by the onset of neurological disorders whose clinical-radiological presentation and temporal evolution had led to the diagnosis of progressive multifocal leukoencephalopathy. In the absence of virological evidence in the cerebrospinal fluid analysis, a stereotactic biopsy of the brain lesions had been performed, making it possible to formally rule out this infectious hypothesis and to demonstrate cerebral invasion by tumour cells. Immuno-chemotherapy combining Rituximab-Cyclophosphamide-Doxorubicin-Vincristine-Prednisone-Ibrutinib (RCHOP-Ibrutinib) with intrathecal chemotherapy resulted in a very good clinical-radiological response. Conclusion: The appearance of neurological manifestations in the context of chronic lymphocytic leukemia must systematically lead to a search for a cerebral localization of the disease. In the absence of virological evidence in the cerebrospinal fluid, any suspicion of progressive multifocal leukoencephalopathy in this context should lead to the histological study of brain lesions.

BMI-1抑制剂PTC-596对人乳腺癌MCF-7细胞增殖、周期和凋亡的影响

目的 分析BMI-1抑制剂PTC-596对人乳腺癌MCF-7细胞增殖、周期和凋亡的影响。方法以人乳腺癌MCF-7细胞为肿瘤细胞模型,正常培养为阴性对照组,25、50 nmol/L PTC-596处理SGC-7901细胞48 h为低、高药物浓度实验组。利用CCK8法分析细胞增殖能力;流式细胞术分别结合PI单染、DCFHDA探针、JC-1探针以及PI/FITC-Annexin V双染分析细胞周期、活性氧(reactive oxygen species, ROS)累积、线粒体膜电位和凋亡细胞比例;Western blot法检测细胞BIM-1蛋白和周期相关蛋白CyclinD1、CyclinB1、P21以及凋亡相关蛋白Bax、Bcl-2、c-PARP蛋白相对表达水平。结果 与对照组相比,PTC-596高效抑制人乳腺癌MCF-7细胞的增殖,处理48 h后IC_(50)为(49.33±7.02)nmol/L。低、高药物浓度实验组细胞中BMI-1表达显著减少(P <0.01)。实验组细胞中CyclinB1和P21相对表达增加,CyclinD1表达减少,细胞有丝分裂被抑制,出现G_2/M期周期阻滞;同时活性氧累积增多,线粒体膜电位下降,Bax表达上调,Bcl-2表达下调,c-PARP增加,凋亡细胞比例从2.04%显著上升为10.56%、26.74%。与对照组相比较,以上结果差异均有统计学意义(P <0.05)。结论 PTC-596高效杀伤人乳腺癌MCF-7细胞,其机制可能与抑制BMI-1、诱导细胞周期阻滞和内源性线粒体途径细胞凋亡密切相关。