Bcl-2参与SCID小鼠体内齐墩果酸诱导HL-60细胞凋亡的调控作用

目的:观察齐墩果酸(OA)对白细胞移植模型小鼠脾脏浸润白血病细胞凋亡数量和Bcl-2蛋白表达的影响,探讨OA对白血病模型鼠的治疗作用机制.方法:取浓度为2×107mL-1体外培养的人早幼粒系白血病HL-60细胞0.5 mL,腹腔注射重症联合免疫缺陷(SCID)小鼠,构建SCID小鼠的HL-60细胞移植瘤模型;模型成功后小鼠分为用药组、白血病模型对照组,并设正常对照组.用药组以200 mg·kg-1OA皮下注射,用药2周后观察各组小鼠的一般状态、外周血象及骨髓象白细胞分类情况,病理学检查脾白血病细胞浸润程度,TUNEL方法测定脾浸润白血病细胞凋亡率,免疫组织化学检测HL-60细胞凋亡相关基因Bcl-2蛋白表达率.结果:成功建立SCID小鼠的HL-60细胞移植瘤模型;用药组小鼠体质量[(15.0±0.8) g]明显高于模型组小鼠[(13.9±0.9) g](P<0.01),小鼠生存期[(50.3±5.5) d]明显高于模型组小鼠[(37.1±4.4) d](P<0.01);与模型组比较,用药组外周血白血病细胞有向正常白细胞分化趋势,可见分叶的白血病细胞,骨髓象中幼稚细胞减少,脾浸润情况改善;用药组小鼠脾浸润白血病细胞凋亡率高于模型组(P<0.01),Bcl-2蛋白表达阳性细胞百分率低于模型组(P<0.01).结论:成功建立白血病移植瘤鼠模型;OA可改变白血病移植瘤模型鼠的一般状态,延长生存期;OA通过降低Bcl-2表达可诱导白血病细胞凋亡.     

天仙子联合湿润烧伤膏治疗化疗性静脉炎的疗效观察

目的 探讨中药天仙子联合湿润烧伤膏治疗化疗性静脉炎的疗效.方法 将115例发生化疗性静脉炎患者,随机分为观察组58例和对照组57例,观察组采用中药天仙子联合湿润烧伤膏治疗,对照组单用湿润烧伤膏治疗.观察并比较2组化疗性静脉炎的总有效率及治疗有效时间.结果 2组总有效率及治疗有效时间比较,差异均有统计学意义(p＜0.01,p＜0.05).结论 采用中药天仙子联合湿润烧伤膏治疗化疗性静脉炎能提高有效率,缩短治疗时间,其疗效优于单用湿润烧伤膏组.     

沙利度胺治疗急性白血病的疗效及对血管调控因子水平的影响

目的 观察沙利度胺联合化疗治疗急性白血病的临床疗效及其对血浆血管内皮生长因子(VEGF)、血管内皮生长因子受体(VEGFR)、碱性成纤维细胞生长因子(bFGF)水平的影响.方法 急性白血病患者36例,随机分为试验组及对照组各18例.每组均予以常规化疗方案标准剂量化疗,试验组同时口服沙利度胺100 mg/d.治疗前及治疗后8周分别采集外周血,双抗体夹心酶联免疫吸附法(ELISA)检测血浆VEGF、VEGFR、bFGF含量.以15位健康体检者为健康对照组.结果 试验组与对照组有效率分别为88.9%(16/18)和77.8%(14/18),差异有统计学意义(x2=4.103,P＜0.05).试验组与对照组治疗前血浆VEGF水平分别为(389.78±249.94)和(318.54±125.78)pg/ml,高于健康组的(132.91±26.66)pg/ml(t=3.141、3.024,均P＜0.01);治疗后分别为(211.74±36.72)和(288.02±31.77)pg/ml,高于健康组(t=2.413、2.324,均P＜0.05);试验组与对照组治疗前VEGF差异无统计学意义(t=1.384,P＞0.05),治疗后差异有统计学意义(t=2.793,P＜0.05).试验组与对照组治疗前血浆VEGFR水平分别为(2490.75±1695.9)和(2322.78±1105.87)pg/ml,高于健康组的(1134.98±378.45)pg/ml(t=2.914、2.783,均P＜0.01);治疗后分别为(1359.71±390.24)和(1753.89±337.04)pg/ml,与健康组相比差异有统计学意义(t=2.572、2.447,均P＜0.05);试验组与对照组治疗前VEGFR差异无统计学意义(t=1.276,P＞0.05),治疗后差异有统计学意义(t=2.486,P＜0.05).试验组与对照组治疗前血浆bFGF水平分别为(2.43±0.27)和(2.4l±0.33)ng/ml,高于健康组的(1.83±0.44)ng/ml(t=4.982、4.171,均P＜0.05);治疗后分别为(2.09±0.17)和(2.11±0.31)ng/ml,与健康组相比差异有统计学意义(t=3.01l、2.773,均P＜0.05);试验组与对照组治疗前及治疗后相比差异无统计学意义(t=0.953、1.282,均P＞0.05).结论 沙利度胺联合化疗可提高急性白血病患者的缓解率,有可能成为一种通过抗血管新生从而抑制白血病细胞生长及浸润的有效治疗方法.     

HSP65-MUC1肿瘤疫苗对小鼠胰腺组织的分子模拟作用

目的:探讨重组抗肿瘤融合蛋白疫苗热激蛋白65-黏蛋白1(HSP65-MUC1)在小鼠体内通过分子模拟方式损伤小鼠胰腺的可能性.方法:21只C57BL/6小鼠随机分为PBS对照组、HSP65组和HSP65-MUC1组(每组7只),分别皮下注射PBS、HSP65和HSP65-MUC1,每周1次,给药3周.无菌分离小鼠脾细胞,利用流式细胞术检测特异性淋巴细胞的增殖情况,组织病理学观察小鼠胰腺的病理改变.结果:流式细胞术检测,与PBS对照组和HSP65组比较,HSP65-MUC1肿瘤疫苗组HSP65-MUC1特异性淋巴细胞升高了16.88%(P<0.001);HSP65特异性淋巴细胞升高了7.29%(P<0.01);与HSP60交叉识别的特异性淋巴细胞升高了5.79%(P<0.05).3个免疫组小鼠胰腺组织HE染色病理均正常.结论:HSP65-MUC1肿瘤疫苗没有通过分子模拟诱导损伤小鼠胰腺.     

卡介苗热休克蛋白70对肿瘤细胞裂解物免疫原性的影响

目的:观察卡介苗热休克蛋白70(BCGHSP70)对肿瘤细胞裂解物(TCL)免疫原性的影响,为TCL相关肿瘤疫苗的制备提供依据.方法:应用冻融法制备B16黑色素瘤细胞裂解物B16TCL,将BCGHSP70与B16TCL在体外混合制备BCGHSP70-B16TCL.将C57BL/6小鼠随机分为BCGHSP70-B16TCL组、PBS组、BCGHSP70组和B16TCL组,分别于第1和14天皮下免疫BCGHSP70-B16TCL、PBS、BCGHSP70和B16TCL.于末次免疫后第7天处死小鼠,MTT法观察不同免疫组小鼠脾淋巴细胞在B16TCL体外刺激后的增殖情况,计算刺激指数(SI).结果:应用冻融法能够使B16细胞完全裂解,所制备的B16TCL中含有丰富的蛋白成分.与PBS组、BCGHSP70组和B16TCL组比较,BCGHSP70-B16TCL组免疫小鼠脾脏明显增大;BCGHSP70-B16TCL免疫组SI高于PBS免疫组(P=0.00)、B16TCL免疫组(P=0.01)和BCGHSP70免疫组(P=0.00).结论:BCGHSP70 能够增强B16TCL的免疫原性,提示BCGHSP70可能作为有效的免疫佐剂用于TCL相关肿瘤疫苗的研究.     

增强子结合蛋白C/EBPα对白血病BALB/c裸鼠的肿瘤抑制作用

目的 探讨增强子结合蛋白C/EBPα在白血病裸鼠体内的肿瘤抑制作用.方法 将30只BALB/c裸鼠随机分转染组(10只)、空载组(10只)、对照组(10只),建立皮下瘤模型,并将30只BALB/c裸鼠如上分组建立白血病模型,将C/EBPα稳定表达细胞株pEGFP-C/EBPα-K562、空载细胞株pEGFP-K562及白血病细胞株K562分别经皮下和尾静脉注射到相应组裸鼠体内,形成皮下瘤和血液病模型.观测皮下肿瘤的变化,应用TUNEL检测细胞的凋亡,瑞特-吉姆萨染色观察血液病模型裸鼠外周血和骨髓中白血病细胞增殖能力,RT-PCR检测增殖相关基因的表达.结果 皮下瘤模型中pEGFP-C/EBPα-K562组肿瘤质量及最大直径为(24±0.1)g和(11±2)mm,空载组和对照组分别为(5.1±0.3)g、(19±3)mm和(5.7±0.4)g、(23±3)mm(均P＜0.05),TUNEL检测发现pEGFP-C/EBPα-K562组肿瘤细胞凋亡明显增加(P＜0.05);血液病模型鼠外周血可见白血病细胞,pEGFP-C/EBPα-K562组白血病细胞增殖能力明显低于空载组和对照组,可见明显细胞分化现象,RT-PCR检测发现p53基因上调和c-myc基因下调.结论 增强子结合蛋白C/EBPα在白血病小鼠体内具有促进肿瘤细胞凋亡和抑制白血病细胞增殖的能力,并能促进白血病细胞分化.C/EBPα的白血病抑制作用可能是通过对相应基因的调控来实现.     

氯化镉对裸鼠皮下移植人肝癌SMMC-7721细胞的抑制作用及其对线粒体酶的影响

目的:研究氯化镉对裸鼠皮下移植人肝癌SMMC-7721细胞的抑制作用及对线粒体乳酸脱氢酶(LDH)、ATP酶活性的影响,阐明氯化镉抑制肿瘤生长的机制.方法:建立人肝癌裸鼠皮下荷瘤模型,分别腹腔注射生理盐水(阴性对照组)、5-氟尿嘧啶(阳性对照组)、氯化镉0.5、1.0和2.0 mg·kg-1(氯化镉组),10 d后测定荷瘤体积、脏器指数和血清ALT、AST水平及荷瘤组织线粒体LDH、ATP酶的活性.结果:与阳性对照组比较,氯化镉0.5、1.0和2.0 mg·kg-1组肿瘤抑制率增加,但差异无统计学意义(P>0.05);各组脏器指数变化不明显,其中氯化镉各剂量组肾脏指数高于阳性对照组(P<0.05);与阴性对照组比较,氯化镉各剂量组ALT水平及LDH酶活性显著降低(P<0.05),0.5和1.0 mg·kg-1组AST水平显著降低(P<0.05);1.0和2.0 mg·kg-1组Ca2+-Mg2+-ATPase活性与阴性对照组比较差异具有统计学意义(P<0.05),0.5和2.0 mg·kg-1组Na+-K+-ATPase活性与阳性对照组比较差异具有统计学意义(P<0.05).结论:氯化镉可能干扰线粒体能量代谢,并通过线粒体途径抑制肿瘤生长.     

海藻色素糖蛋白对小鼠H22肝癌细胞增殖与凋亡的影响

目的:研究麒麟菜海藻色素糖蛋白(seaweed pigment glycoprotein,SPG)对小鼠H22肝癌细胞增殖与凋亡的影响.方法:将不同浓度SPG与小鼠H22肝癌细胞共同培养,用MTT法测定癌细胞增殖活性.建立H22移植瘤小鼠肝癌模型,随机分为SPG高、中、低剂量组,对照组及环磷酰胺组.实验组小鼠每天分别给予不同剂量(100、50、10 mg/kg)的SPG灌胃,连续10 d,对照组同法给予等量生理盐水,环磷酰胺组小鼠腹腔注射20 mg/kg环磷酰胺,隔日一次.各组小鼠均于末次给受试物后24 h处死,取肿瘤组织用免疫组化法检测各组Bcl-2和Bax蛋白表达.结果:SPG高剂量组瘤细胞增殖活性(0.545±0.002)明显高于对照组(0.404±0.008)(P<0.05);SPG高剂量组Bcl-2和Bax蛋白阳性表达率分别为16.78%和38.1%,对照组分别为65.16%和4.68%,两组间的差异具有统计学意义(P<0.05).结论:SPG具有抑制小鼠H22肝癌细胞增殖、促进其凋亡的作用.     

甲硝唑联合利多卡因含漱治疗化疗并发口腔溃疡的临床分析

目的 探讨甲硝唑联合利多卡因含漱治疗化疗并发口腔溃疡的临床效果.方法 采用回顾性分析的方法,分析我院收治化疗并发口腔溃疡患者临床资料,依据治疗方式不同分为观察组和对照组.结果 观察组临床治疗的总有效率明显高于对照组,差异有统计学意义(P＜0.05).两组患者均无不良反应发生.结论 甲硝唑联合利多卡因含漱治疗化疗并发口腔溃疡的临床效果明显,值得临床推广应用.     

阿仑膦酸钠联合钙剂治疗老年性骨质疏松的疗效观察

目的:比较阿仑膦酸钠联合钙剂与单用钙剂治疗重度老年性骨质疏松症的疗效差异.方法:本研究为随机对照试验,入组的42例老年性骨质疏松患者随机分为两组,分别联合服用阿仑膦酸钠及钙尔奇D600(治疗组,n=21)或单独服用钙尔奇D (对照组,n=21),治疗3月.分别于试验前后以疼痛数字评价量表评价患者骨痛情况,并测定骨密度(BMD)及血清钙、磷、碱性磷酸酶等指标.结果:试验结束时治疗组患者骨痛好转率及BMD改善率显著高于对照组,血清骨代谢的生化指标则无明显差异.结论:阿仑膦酸钠联合钙剂治疗老年性骨质疏松症疗效显著优于单用钙剂.     

Importance of cyclophosphamide-induced bystander effect on T cells for a successful tumor eradication in response to adoptive immunotherapy in mice

Cyclophosphamide (CTX) increases the antitumor effectiveness of adoptive immunotherapy in mice, and combined immunotherapy regimens are now used in some clinical trials. However, the mechanisms underlying the synergistic antitumor responses are still unclear. The purpose of this study was (a) to evaluate the antitumor response to CTX and adoptive immunotherapy in mice bearing four different syngeneic tumors (two responsive in vivo to CTX and two resistant); and (b) to define the mechanism(s) of the CTX-immunotherapy synergism. Tumor-bearing DBA/2 mice were treated with a single injection of CTX followed by an intravenous infusion of tumor-immune spleen cells. In all the four tumor models, a single CTX injection resulted in an impressive antitumor response to the subsequent injection of spleen cells from mice immunized with homologous tumor cells independently of the in vivo response to CTX alone. Detailed analysis of the antitumor mechanisms in mice transplanted with metastatic Friend leukemia cells revealed that (a) the effectiveness of this combined therapy was dependent neither on the CTX-induced reduction of tumor burden nor on CTX-induced inhibition of some putative tumor-induced suppressor cells; (b) the CTX/immune cells' regimen strongly protected the mice from subsequent injection of FLC, provided the animals were also preinoculated with inactivated homologous tumor together with the immune spleen cells; (c) CD4(+) T immune lymphocytes were the major cell type responsible for the antitumor activity; (d) the combined therapy was ineffective in mice treated with antiasialo-GM1 or anti-IFN-alpha/beta antibodies; (e) spleen and/ or bone marrow cells from CTX-treated mice produced soluble factors that assisted in proliferation of the spleen cells. Altogether, these results indicate that CTX acts via bystander effects, possibly through production of T cell growth factors occurring during the rebound events after drug administration, which may sustain the proliferation, survival, and activity of the transferred immune T lymphocytes. Thus, our findings indicate the need for reappraisal of the mechanisms underlying the synergistic effects of CTX and adoptive immunotherapy, and may provide new insights into the definition of new and more effective strategies with chemotherapy and adoptive immunotherapy for cancer patients.     

Zinc depletion suppresses tumor growth in mice

The hypothesis that in tumor-bearing animals an increase of host hepatic zinc metallothionein (Zn-MT) causes a restriction of zinc in the tumor tissue was studied. Three types of tumors were induced in laboratory mice by cell transplant. Tumor growth appears to be inhibited under zinc-deficient conditions, even in cases where zinc deficiency was started after tumor cell transplant. The survival times of tumor-bearing mice were prolonged by administration of cadmium chloride, which induces the synthesis of a combined zinc-cadmium metallothionein derivative in the host liver, but not in the tumor tissue, leading to an increase of hepatic zinc in the treated animals. The uptake of 65Zn by the liver of Cd-treated, tumor bearing mice was significantly higher than that of controls whereas uptake of 65Zn by tumor cells was significantly higher in controls than in the treated animals. These results suggest that restriction of zinc intake suppresses tumor growth.     

Enhancement of tumor killing using a combination of tumor immunization and HSV-tk suicide gene therapy

Tumor cells genetically modified with the herpes simplex virus thymidine kinase (HSV-tk) gene in combination with ganciclovir (GCV) demonstrate a "bystander effect". Previous attempts to enhance the bystander tumor killing by combining cytokine genes with HSV-tk/GCV have met with varying results. The present study was designed to determine the effects of tumor immunization in combination with HSV-tk gene-modified tumor cells and GCV on tumor killing and to determine if the bystander tumor killing could be enhanced. Tumor-bearing mice immunized with syngeneic tumor (KBALB) prior to treatment with an i.p. injection of xenogeneic HSV-tk gene-modified tumor cells (PA-1STK) had prolonged animal survival (group 4, 56.4 days). In contrast, unimmunized tumor-bearing mice (group 2) or tumor-bearing mice immunized to the xenogeneic PA-1STK tumor cells (group 5) showed a mean survival of about 27 days after receiving an i.p. injection of PA-1STK cells and GCV. Control groups, which were either not immunized and did not receive HSV-tk cells (group 1) or immunized but treated only with GCV (group 3) showed short survival (16-18 days). Analysis of tumors for cytokine mRNA expression revealed increased TNF-alpha and IL-1alpha mRNA expression in group 4 mice. Furthermore, IL-2 mRNA expression was detectable on days 2 and 4 only in group 4 mice. Immunophenotypic analysis for tumor-infiltrating lymphocytes demonstrated an increase in macrophage (4%, p = 0.0001) and T cells (1.8%, p < 0.001) in group 4 mice with an enhanced T-cell response as compared with mice from groups 1, 2 and 3. Our results demonstrate that tumor immunization combined with HSV-tk/GCV treatment results in increased animal survival with enhanced immune response. Furthermore, the cytokine milieu observed in the present study can modulate the tumor micro-environment in vivo from one that is immunosuppressive to one that is immune-stimulatory.     

Posttraumatic hypothermia in the treatment of axonal damage in an animal model of traumatic axonal injury

Twenty-one-day-old BALB/c mice were shaved on the back to synchronize hair growth. On day 30 or 31, when at least 90% of mice exhibited hair regrowth in the shaved area, 1,25(OH)2D3 was applied topically to the shaved area daily for 5 days. On the 6th day, cyclophosphamide (Cytoxan, CTX) was injected i.p. to induce hair loss in the shaved area. Alopecia was induced in a dose-dependent manner by CTX treatment within 1 to 2 weeks. This effect was reduced significantly if mice were pre-treated with 1,25(OH)2D3, though only slight protection was observed in female mice. Interestingly, this 1,25(OH)2D3-mediated protection against hair loss was attenuated in male mice but became more significant in female mice when they were inoculated with the EMT-6 murine mammary tumor prior to treatment. More importantly, topical treatment with 1,25(OH)2D3 alone was able to inhibit EMT-6 tumor growth in both male and female BALB/c mice. Furthermore, 1,25(OH)2D3 pre-treatment also augmented the anti-tumor effect of CTX. Our results demonstrate that topical application of 1,25(OH)2D3 can protect against CTX-induced alopecia both in tumor-free and in tumor-bearing mice in a sex-dependent manner. Moreover, 1,25(OH)2D3 was shown, either alone or in combination with CTX, to inhibit tumor growth.     

Regression of established mouse leukemia by GM-CSF-transduced tumor vaccine: implications for cytotoxic T lymphocyte responses and tumor burdens

This study investigated the therapeutic effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on a mouse leukemia model. By using a retroviral vector, mouse GM-CSF cDNA was transduced into a highly tumorigenic T leukemia cell line, RL male 1. Injection of GM-CSF-secreting RL male 1 cells into syngeneic BALB/c mice elicited protective immunity in the animals, which could regress preestablished tumors introduced either by a subcutaneous or in an intravenous route. However, the therapeutic effects were less prominent in the mice inoculated with a large tumor load or in mice treated later. Winn tests further demonstrated that the splenocytes from the late-treated group conferred poorer protective effects in terms of reducing the growth of parental RL male 1 cells in naive mice than the splenocytes from the early-treated group. Nonetheless, upon stimulation in vitro, the activity of tumor-specific cytotoxic T lymphocytes (CTL) was comparable in the splenocytes of both groups of mice. Histological analysis also indicated that the CD8+ T cells appeared as early as 3 days following vaccination at the vaccine sites and at the tumor sites in both groups of mice. Above observations implied that the T cells in the animals bearing large tumors appeared to be in a state of suppression or anergy. Systematic histological analyses for 2 weeks provided further insight into various infiltrates at the vaccine sites and at the tumor sites in response to the inoculation of GM-CSF-secreting tumor vaccine.     

Cellular and humoral immunity to leukemia cells in BCG-induced growth control of a murine leukemia

The antitumor effects of weekly iv injections of 1.0 mg BCG and/or sc injections of 10(7) irradiated leukemia cells were studied in an isogeneic, transplantable lymphoid leukemia in the C57BL/6 mouse. The injections were started at day 1 after ip inoculation of 10(5) leukemia cells. BCG prolonged the survival time of most animals and cured 22%. BCG plus irradiated cells cured only about 10% of the mice, and irradiated cells alone had no curative effect. Individual tumor-bearing mice in the various experimental groups were examined with respect to ascites tumor cell number; complement-dependent cytotoxic antibodies in sera; direct and antibody-dependent cytotoxicity to tumor cells of lymphoid cells from peritoneal fluid, the spleen, and peripheral lymph nodes; and the cytology of ascites, the spleen, and lymph nodes. Only the antibody-dependent lymphocyte-mediated cytotoxicity (ADLMC) was correlated with the ascites tumor cell number, since the ADLMC was high only in mice with a tumor cell number less than that of the controls. Furthermore, since mice with a low tumor cell number had predominantly only lymphocytes as the nonmalignant cell type in their peritoneal fluid, ADLMC may have had an important role in BCG-induced control of tumor growth.     

低剂量辐射对环磷酰胺化疗毒性作用的影响

Objective:The aim of the study was to investigate the effects as well as the possible mechanisms of low dose y-ray pre-irradiation on hepatic damage, DNA damage of peripheral lymphocytes and genetic material damage caused by high dosage of cyclophosphamide (CTX). Methods: Kunming strain male mice were randomly divided into five groups:control group, sham-irradiated group, low dose irradiation group (LDR group), cyclophosphamide chemotherapy group (CTX group) and low close irradiation combined with chemotherapy group (LDR + CTX group). Having being raised for one week,all the mice were implanted subcutaneously with S180 cells in the left inguen (control group excluded). On days 8 and 11,mice of LDR and LDR + CTX groups were given 75 mGy whole-body y-irradiation, 30 h later mice of CTX and LDR + CTX groups were injected I.p. 3.0 mg cyclophosphamide. All the mice were sacrificed on day 13. DNA damage of the peripheral lymphocytes was analyzed using single cell gel electrophoresis (SCGE); ALT activity, total protein (TP) and albumin (ALB)of the plasma were analyzed using automatic biochemistry analyzer; MDA content, SOD and GSH-PX activity of the hepatic homogenate were analyzed using chromometry; genetic material damage was analyzed using micronucleus frequency (MNF)of polychromatoerythrocytes (PCE) in bone marrow. Results: 1. Differences of MDA contents, SOD and GSH-PX activity of hepatic homogenate between 5 groups had notable statistical significance (P < 0.01); in control group MDA content was the lowest, SOD and GSH-PX activity were the highest, while in CTX group MDA content was the highest, SOD and GSH-PX activity were the lowest; compared with CTX group MDA content decreased significantly (P < 0.01) and SOD and GSH-PX activity increased significantly (P <0.05) in LDR + CTX group. 2. Differences of ALT activity of plasma between 5 groups had no statistical significance (F = 1.262, P > 0.05). Differences of TP and ALB of plasma between 5 groups had statistical sig-nificance (F = 12.879 and 6.336 respectively, P < 0.01); TP and ALB in control group were higher than those of other groups and compared with sham-irradiated group, TP and ALB in LDR group elevated significantly (P < 0.05). 3. Differences of DNA damage of peripheral lymphocytes had notable statistical significance (F = 6.383, P < 0.01); DNA damage in control group was the lightest, while DNA damage in CTX group was the severest; compared with CTX group, DNA damage in LDR + CTX group was much lighter (P < 0.05). 4. MNF of PCE between 5 groups had remarkable significance (F = 179.652, P < 0.01);compared with control group and sham-irradiated group, MNF in CTX group increased significantly (P < 0.01); compared with CTX group, MNF in LDR + CTX group had a tendency of decline, which had no statistical significance (P > 0.05). Conclusion:1. CTX can damage the hepatic tissue through oxidative stress; 75 mGy y-irradiation before CTX chemotherapy can induce activities of anti-oxidative enzymes, promote elimination of free radicals, so as to alleviate the damaging effects of oxidative stress to hepatic tissue caused by high-close chemotherapy. 2. A 75 mGy y-irradiation before CTX chemotherapy has no obvious effect on ALT activity of plasma, but may have protective effect on the protein synthesis function of liver. 3. High-close CTX chemotherapy can cause DNA damage of peripheral lymphocytes; 75 mGy y-irradiation before chemotherapy may have certain protective effect on DNA damage. 4. CTX has potent mutagenic effect, can cause significant increase of MNF of PCE;75 mGy y-ray pre-irradiation did not show obvious protection against genetic toxicity of high-dose CTX chemotherapy.     

Treatment-related leukemia in breast cancer patients treated with fluorouracil-doxorubicin-cyclophosphamide combination adjuvant chemotherapy: the University of Texas M.D. Anderson Cancer Center experience

PURPOSE: Adjuvant chemotherapy for breast cancer has been the routine practice in the past decade. A number of studies have observed an increased incidence of treatment-related leukemias following chemotherapy with alkylating agents and/or topoisomerase II inhibitors. We evaluated the incidence of treatment-related leukemias in breast cancer patients treated in four adjuvant and two neoadjuvant chemotherapy trials at The University of Texas M.D. Anderson Cancer Center. PATIENTS AND METHODS: Between 1974 and 1989, 1,474 patients with stage II or III breast cancer were treated in six prospective trials of adjuvant (n = 4) or neoadjuvant (n = 2) chemotherapy with fluorouracil, doxorubicin, and cyclophosphamide (CTX) (FAC) with or without other drugs. The median observation time was 97 months. In 1,107 patients, FAC chemotherapy was given postoperatively; 367 patients received induction chemotherapy, as well as postoperative chemotherapy. Eight hundred ten patients had surgery followed by radiotherapy and chemotherapy; 664 patients had surgery and chemotherapy only. Patients in two adjuvant and one neoadjuvant study received higher cumulative doses of CTX compared with those in the other studies. RESULTS: Fourteen cases of leukemia were observed. Twelve of these patients had received radiotherapy and chemotherapy, and two had received chemotherapy only. Six of the reported patients with leukemia were treated with a cumulative CTX dose of greater than 6 g/ m2. Five of these patients had received both radiotherapy and chemotherapy. The median latency period in the 14 patients was 66 months (range, 22 to 113). Six of 10 patients with adequate cytogenetic analyses had abnormalities that involved chromosomes 5 and/or 7. The rest of the patients had nonspecific cytogenetic abnormalities or lacked cytogenetic information. The 10-year estimated leukemia rate was 1.5% (95% confidence interval [CI], 0.7% to 2.9%) for all patients treated, 2.5% (95% CI, 1.0% to 5.1%) for the radiotherapy-plus-chemotherapy group, and 0.5% (95% CI, 0.1% to 2.4%) for the chemotherapy-only group; this difference was statistically significant (P = .01). The 10-year estimated leukemia risk for the higher-dose (> 6 g/m2) CTX group was 2% (95% CI, 0.5% to 5.0%) compared with 1.3% (95% CI, 0.4% to 3.0%) for the lower-dose group, a difference that was not statistically significant (P = .53). CONCLUSION: These data illustrate that patients treated with adjuvant FAC chemotherapy plus radiotherapy have a slightly increased risk of leukemia. This information needs to be considered in the treatment plans for patients with breast cancer. However, for most patients, the benefits of adjuvant therapy exceed the risk of treatment-related leukemia.     

Use of chlorotoxin for targeting of primary brain tumors

Gliomas are primary brain tumors that arise from differentiated glial cells through a poorly understood malignant transformation. Although glioma cells retain some genetic and antigenic features common to glial cells, they show a remarkable degree of antigenic heterogeneity and variable mutations in their genome. Glioma cells have recently been shown to express a glioma-specific chloride ion channel (GCC) that is sensitive to chlorotoxin (CTX), a small peptide purified from Leiurus quinquestriatus scorpion venom [N. Ullrich et al, Neuroreport, 7: 1020-1024, 1996; and N. Ullrich and H. Sontheimer, Am. J. Physiol. (Cell Physiol.), 270: C1511-C1521, 1996]. Using native and recombinant 125I-labeled CTX, we show that toxin binding to glioma cells is specific and involves high affinity [dissociation constant (Kd)=4.2 nM] and low affinity (Kd=660 nml) binding sites. In radioreceptor assays, 125I-labeled CTX binds to a protein with Mr=72,000, presumably GCC or a receptor that modulates GCC activity. In vivo targeting and biodistribution experiments were obtained using 125I- and (131)I-labeled CTX injected into severe combined immunodeficient mice bearing xenografted gliomas. CTX selectively accumulated in the brain of tumor-bearing mice with calculated brain: muscle ratios of 36.4% of injected dose/g (ID/g), as compared to 12.4% ID/g in control animals. In the tumor-bearing severe combined immunodeficient mice, the vast majority of the brain-associated radioactivity was localized within the tumor (tumor:muscle ratio, 39.13% ID/g; contralateral brain:muscle ratio, 6.68%ID/g). Moreover, (131)I-labeled CTX distribution, visualized through in vivo imaging by gamma ray camera scans, demonstrates specific and persistent intratumoral localization of the radioactive ligand. Immunohistochemical studies using biotinylated and fluorescently tagged CTX show highly selective staining of glioma cells in vitro, in situ, and in sections of patient biopsies. Comparison tissues including normal human brain, kidney, and colon were consistently negative for CTX immunostaining. These data suggest that CTX and CTX-conjugated molecules may serve as glioma-specific markers with diagnostic and therapeutic potential.     

Cisplatin-based neoadjuvant chemotherapy and combined resection for ethmoid sinus adenocarcinoma reaching and/or invading the skull base

OBJECTIVE: To review our experience with cisplatin-based neoadjuvant chemotherapy before en bloc resection via a combined neurosurgical and transfacial approach for ethmoid sinus adenocarcinoma reaching and/or invading the skull base. DESIGN: Case series. SETTING: A tertiary care center and university teaching hospital. PATIENTS: Twenty-two patients with primary untreated ethmoid sinus adenocarcinoma reaching and/or invading the skull base consecutively treated between 1984 and 1992 with cisplatin-based neoadjuvant chemotherapy and combined neurosurgical and transfacial approach. MAIN OUTCOME MEASURES: Statistical analysis of survival, local control, nodal recurrence, distant metastasis, and metachronous second primary tumor incidence based on the Kaplan-Meier actuarial method. Univariate analysis was performed to analyze the relationships between various factors, survival, and local recurrence. Clinical response, histological response, toxic effects of chemotherapy, and postoperative course were also reported. RESULTS: The Kaplan-Meier 3-year survival, local control, nodal recurrence, and distant metastasis estimates were 68.1%, 65.7%, 5.3%, and 10%, respectively. Metachronous second primary tumor was not encountered in our series. Survival was statistically more likely to be reduced in patients with intrasphenoidal tumor extent (P = .04) and local recurrence (P = .01). Local recurrence was statistically more likely in patients with intrasphenoidal tumor extent (P = .002) and no response to cisplatin-based neoadjuvant chemotherapy (P = .03). CONCLUSIONS: The results achieved suggest that cisplatin-based neoadjuvant chemotherapy before combined neurosurgical and transfacial approach should be further investigated for the treatment of ethmoid sinus adenocarcinoma reaching and/or invading the skull base.