肝激酶B1增强肺癌H460细胞放射敏感性的体内研究

目的 研究肝激酶B1(LKB1)对肺癌H460细胞裸鼠皮下移植瘤放射敏感性的影响。方法 构建肺癌H460细胞裸鼠皮下移植瘤模型,分别给予空载质粒(pEGFP-Ctrl)、照射+空载质粒(IR+pEGFP-Ctrl)、过表达LKB1质粒(pEGFP-LKB1)、照射+过表达LKB1质粒(IR+pEGFP-LKB1)处理;观察移植瘤生长情况,计算抑瘤率及放射增敏比;并采用免疫组织化学和蛋白印记技术检测各组瘤组织中LKB1表达情况,分析LKB1与放射敏感性的关系。结果 相较于pEGFP-Ctrl组,IR+pEGFP-Ctrl组、pEGFP-LKB1组和IR+pEGFP-LKB1组的肿瘤生长都受到不同程度的抑制,抑瘤率分别为31.30%、14.78%和43.48%,其中IR+pEGFP-LKB1组较其他组最为明显。IR+pEGFP-LKB1组LKB1的放射增敏系数为1.18。转染pEGFP-LKB1组的LKB1在免疫组织化学和蛋白印记水平上表达增高,其余组未见LKB1表达。结论 成功构建肺癌H460细胞裸鼠皮下移植瘤模型,LKB1具有增强肺癌H460细胞裸鼠皮下移植瘤放射敏感性作用。     

放射诱导抑瘤素M靶向肿瘤表达治疗肺癌实验研究

目的利用放射敏感性调控序列诱导抑瘤素M(OSM)靶向肺癌表达，探索肺癌治疗新方法。方法利用基因重组构建放射可调控的OSM表达载体pEO，转染肺腺癌A549细胞，观察γ线照射后细胞OSM表达及其对细胞相对存活分数和存活曲线的影响。利用肺癌移植瘤观察不同处理的抑瘤效应。结果γ线可诱导OSM在pEO转染肺癌细胞表达显著上调，呈剂量依赖性。pEO转染肺癌细胞株对辐射敏感性增强，增殖活性显著受抑。6Gy照射联合pEO转染可显著抑制移植瘤生长，并可使30％的移植瘤完全消退。结论由辐射敏感性启动子驱动的OSM肿瘤靶向性表达，可望为肺癌治疗提供一条新途径。     

非小细胞肺癌病人源性NOD/SCID小鼠和BALB/c裸鼠移植瘤模型的建立及比较

目的：构建人非小细胞肺癌的NOD/SCID小鼠和BALB/c裸鼠移植瘤模型,并探讨移植瘤成瘤性与小鼠品系间的关系,为后续建立优良的动物模型奠定基础。方法：取手术切除获得的23例非小细胞肺癌组织,1 h内移植于NOD/SCID小鼠或BALB/c裸鼠皮下,观察移植瘤成瘤情况,测量移植瘤体积,绘制生长曲线图,计算成瘤率、成瘤潜伏时间和成瘤时间,分析并比较移植成瘤组和未成瘤组所对应患者的相关临床病理指标,并取移植成瘤组和所对应患者的组织标本进行病理学分析。结果：NOD/SCID小鼠皮下移植瘤模型成瘤率（55.6%）,BALB/c裸鼠皮下移植瘤模型（20%）,两者间差异无统计学意义（P > 0.05）,但前者的成瘤潜伏时间和成瘤时间均短于后者（P < 0.05）。患者相关临床病理指标中鳞癌、TNM分期和淋巴结转移情况与移植瘤成瘤建模无明显相关（P=0.109、0.153、0.077）,NOD/SCID小鼠和BALB/c裸鼠皮下移植瘤模型均能保持病人肺癌肿瘤组织的形态学特征。结论：成功构建了NOD/SCID小鼠和BALB/c裸鼠皮下移植瘤模型,NOD/SCID小鼠更适宜用于肺癌病人源性皮下移植瘤模型的建立,非小细胞肺癌移植瘤模型的建立为进行体外抗肿瘤药物的筛选提供了良好的研究工具。     

多功能纳米金在肺腺癌A549荷瘤小鼠模型中的放射增敏作用及Micro CT成像研究

目的 探究多功能纳米金在肺腺癌A549荷瘤小鼠模型中的放射增敏作用及Micro CT成像。方法 荷瘤小鼠瘤体内注射纳米金,分别行160 kV X线及6 MV X线不同能量级照射,并测量肿瘤体积变化。瘤体内注射纳米金,在不同时间点行Micro CT扫描,观察纳米金在瘤组织中的成像及沉积时间。结果 对照组与纳米金组肿瘤体积变化无明显差异(P=0.941)。6 MV X线联合纳米金组与6 MV X线组比较肿瘤体积略缩小,但两组没有统计学差异(P=0.730)。160 kV X线联合纳米金组肿瘤体积明显小于160 kV X线组(P=0.026)。Micro CT扫描显示纳米金在肿瘤中的沉积时间可持续30天,成像效果很好,且未见纳米金相关毒性。结论 多功能纳米金对160 kV X线照射肺腺癌A549移植瘤有明显的放射增敏作用;纳米金瘤体的稳定CT成像可作为图像引导放疗肿瘤靶区定位和勾画的一种潜在方法。     

肝素和氢化可的松对人肺癌抑瘤作用的体内实验研究

目的：研究肝素和氢化可的松的联合应用对人肺癌裸鼠皮下移植瘤生长抑制作用和对肿瘤血管生成、肿瘤细胞增殖及凋亡的影响，探讨肝素和氢化可的松联合应用抑制肿瘤血管生成的可能性。方法：建立人肺癌裸鼠皮下移植瘤模型，通过观察瘤体生长情况、免疫组化法测定微血管密度计数和肿瘤组织的增殖情况、电镜观察肿瘤组织凋亡情况和原位细胞凋亡检测，研究肝素和氢化可的松联合应用的抗血管生成和抑瘤作用。结果：肝素和氢化可的松治疗组瘤体生长较对照组明显受抑，且肿瘤组织微血管生成减少、增殖降低、凋亡增多。结论：肝素和氢化可的松联合应用具有明显的抗血管生成和抑瘤作用。     

人重组血管内皮抑素联合放疗对鼻咽癌CNE-2裸鼠移植瘤抑制及其机制的探讨

目的:观察人重组血管内皮抑素(恩度)联合放射治疗对鼻咽癌CNE-2裸鼠移植瘤的生长作用及血管内皮生长因子(VEGF)和增殖细胞核抗原(PCNA)表达的影响.方法:皮下接种CNE-2细胞制作人鼻咽癌CNE-2裸鼠移植瘤模型,小鼠随机分为空白对照组、恩度组、放疗组和恩度联合照射组4组.分别采用生理盐水、恩度、放疗和恩度+放疗等干预.于放疗后11d处死,取出肿瘤,绘制肿瘤生长曲线,计算抑瘤率,免疫组化(Envision)法测定VEGF和PCNA的表达.结果:恩度组、放疗组及恩度联合照射组均能不同程度抑制移植瘤的生长,其中以恩度联合照射组最明显,P＜0.05;VEGF和PCNA蛋白的表达各治疗组有不同程度的降低,其中联合组下降最为明显,P＜0.05.结论:恩度和放疗联用对鼻咽癌裸小鼠有明显肿瘤抑制作用,其机制可能与下调VEGF和PCNA的表达、抑制新生血管的生成,进而抑制细胞增殖有关.     

羟基红花黄色素A对小鼠Lewis肺癌移植瘤的抑制作用

目的 研究羟基红花黄色素A(hydroxysafflor yellow A,HSYA)对C57BL/6小鼠Lewis肺癌移植瘤的血管抑制作用.方法 C57BL/6近交系小鼠30只,造模后,分为5组,每组6只,分别使用生理盐水、环磷酰胺(CTX)及HSYA(分低、中、高3个剂量)作用于动物模型.观察各组肿瘤体积大小,分析小鼠生长曲线,并在造模第22天处死所有小鼠,无菌条件下剥取瘤组织进行HE染色,观察不同浓度HSYA在不同视野下对肿瘤血管的抑制情况.结果 HSYA中、小剂量组对小鼠移植瘤血管生成有一定抑制作用.结论 中药羟基红花黄色素A(HSYA)对Lewis肺癌小鼠移植瘤血管生成有一定的抑制作用.     

生酮饮食对人肺癌细胞裸鼠皮下移植瘤生长的影响

目的： 建立人肺癌细胞裸鼠皮下移植瘤模型,观察生酮饮食对裸鼠皮下移植瘤生长的影响并对其作用机制进行研究。方法： 10只雌性BALB/c裸鼠右下肢皮下注射人肺癌A549细胞,建立肺癌细胞裸鼠移植瘤模型后,随机分为标准饮食组（SD组）和生酮饮食组（KD组）,分组当天测量裸鼠体质量、移植瘤体积、血糖及血酮浓度,以后每5 d测量1次。接种肿瘤细胞后第30天,摘眼球取血处死裸鼠,取血后进行血脂四项检测。剥离移植瘤组织,分别采用Western blot及免疫组织化学方法检测裸鼠移植瘤组织中4-HNE蛋白的表达水平。结果： 接种肿瘤细胞后第15天起,KD组裸鼠血酮浓度较SD组升高,血糖浓度较SD组降低,差异均有统计学意义（P < 0.05）。接种肿瘤细胞后第20天起,KD组裸鼠体质量及移植瘤体积小于SD组,差异均有统计学意义（P < 0.05）。接种肿瘤细胞后第30天,KD组裸鼠的总胆固醇（CHOL）、高密度脂蛋白胆固醇（HDL-C）、低密度脂蛋白胆固醇（LDL-C）浓度高于SD组,甘油三酯（TG）浓度低于SD组,差异均有统计学意义（P < 0.05）。Western blot法分析结果显示KD组裸鼠移植瘤组织中4-HNE蛋白相对表达水平（1.45±0.10）高于SD组（1.00±0.03）,差异有统计学意义（P < 0.05）。免疫组化法检测结果显示KD组裸鼠移植瘤组织中4-HNE表达水平（4.40±0.89）高于SD组（2.40±0.89）,差异有统计学意义（P < 0.05）。结论： 生酮饮食可以抑制人肺癌细胞裸鼠皮下移植瘤的生长,其作用机制可能与肿瘤细胞氧化应激的增强有关。     

小紫胡汤合并放疗对C57／BL荷瘤小鼠的实验研究

目的 研究荷瘤小鼠放疗合并中药小柴胡汤对瘤体的病理学变化.方法 对C57/BL小鼠63只,随机分为9组,每组7只鼠,设空白对照组(即未移植肿瘤组),实验对照组(即移植瘤未予处理组)、小柴胡汤治疗组、用6mev电子束单纯照射组（又分10，15，20Gy3个剂量组）和小柴胡汤联合照射组（10、15、20Gy3个剂量组）。照射后10d取瘤组织光镜观察病理学的变化。结果 荷瘤鼠经不同方法治疗后肿瘤形态学的变化。小柴胡汤联合20Gy照射组明显优于其他各组的效果。结论 小柴胡汤联合照射增强抗肿瘤效果。     

CpG对X线放射治疗Lewis肺癌小鼠移植瘤的增敏效应

目的: 探讨含胞嘧啶磷酸盐鸟嘌呤基序的寡脱氧核苷酸（cytosinephosphateguanine oligodeoxynucleotide，CpG ODN）对X线照射荷瘤小鼠Lewis肺癌的放疗增敏作用。方法: 在小鼠右前腋窝接种Lewis肺癌细胞，制备荷瘤小鼠模型，将32只荷瘤小鼠随机分为4组：对照组，无任何处理； X线照射组，3 Gy/次，第1、3、5、8、10、12天照射，总剂量18 Gy； CpG组，第1、3、5、8、10、12天注射，每次腹腔注射CpG ODN 0.05 mg；D组：CpG+X 线照射组,每次X线照射前6 h腹腔注射CpG ODN。观察各组移植瘤生长速度和各治疗组移植瘤生长延迟时间，HE染色法观察移植瘤组织病理变化，TUNEL法检测细胞凋亡。结果: 成功建立荷Lewis肺癌小鼠模型，经治疗后各组小鼠移植瘤体积都较对照组明显减小（P<0.01），CpG+X线照射组移植瘤体积最小；X线照射组移植瘤的生长延迟时间为2.1 d，CpG组为2.3 d，CpG+X线照射组为4.8 d，CpG ODN的放射增敏比为2.09。HE染色病理观察到各治疗组都较对照组移植瘤坏死明显，CpG+X线照射组最显著。TUNEL法检测对照组瘤组织细胞凋亡率为（2.75±0.89）%，X线照射组为（4.87±1.13）%，CpG组为（7.63±1.41）%，CpG+X线照射组为（32.63±4.66）%；各治疗组都明显高于对照组，CpG+X线照射组显著高于X线放射组和CpG组(P<0.01)。结论: CpG ODN能明显提高Lewis肺癌移植瘤对X线的放射敏感性，促进肿瘤细胞凋亡。     

重组内皮抑素对肿瘤血管结构和乏氧改善作用的实验观察

目的 观察重组内皮抑素作用下小鼠Lewis肺癌移植瘤在血管退化前是否存在血管正常化时间窗,在此时间窗内肿瘤乏氧是否改善.方法 激光共聚焦显微镜动态观察重组内皮抑素作用下肿瘤血管的形态学变化,免疫组化染色检测不同时间段肿瘤乏氧细胞比例,观测肿瘤生长情况并绘制肿瘤生长曲线.结果 重组内皮抑素处理后肿瘤血管密度逐渐下降,连续治疗9 d较对照组下降最为明显.重组内皮抑素处理后周细胞覆盖内皮细胞比例逐渐增加,第3天开始明显增加,第5天增加最明显,第7天后明显下降.对照组基底膜与内皮细胞连接松散,厚度增加,而重组内皮抑素处理后,基底膜与内皮细胞连接紧密,厚度下降.在重组内皮抑素处理后第5天肿瘤乏氧细胞比例下降最明显,连续5 d用重组内皮抑素,肿瘤生长未见加快.结论 重组内皮抑素能使肿瘤血管正常化,其时间窗为治疗后3～7 d;此时肿瘤氧供明显改善,为临床联合应用放疗和重组内皮抑素提供了实验依据.

Abstract：

Objective To investigate whether recombinant human endostatin can create a time window of vascular normalization prior to vascular pruning to alleviate hypoxia in Lewis lung carcinoma in mice. Methods Kinetic changes in morphology of tumor vasculature in response to recombinant human endostatin were detected under a confocal microscope with immunofluorescent staining in Lewis lung carcinomas in mice. The hypoxic cell fraction of different time was assessed with immunohistochemical staining . Effects on tumor growth were monitored as indicated in the growth curve of tumors . Results Compared with the control group vascularity of the tumors was reduced over time by recombinant human endostatin treatment and significantly regressed for 9 days. During the treatment, pericyte coverage increased at day 3, increased markedly at day 5, and fell again at day 7. The vascular basement membrane was thin and closely associated with endothelial cells after recombinant human endostatin treatment, but appeared thickened, loosely associated with endothelial cells in control tumors. The decrease in hypoxic cell fraction at day 5 after treatment was also found. Tumor growth was not accelerated 5 days after recombinant human endostatin treatment. Conclusions Recombinant human endostatin can normalize tumor vasculature within day 3 to 7, leading to improved tumor oxygenation. The results provide important experimental basis for combining recombinant human endostatin with radiation therapy in human tumors.     

SU11248 maintenance therapy prevents tumor regrowth after fractionated irradiation of murine tumor models

Receptor tyrosine kinase activation contributes to cell viability during cytotoxic therapy. The novel broad spectrum receptor tyrosine kinase inhibitor, SU11248, inhibits vascular endothelial growth factor receptor 2, platelet-derived growth factor receptor, c-kit, and fetal liver tyrosine kinase 3. In this study, we maintained SU11248 plasma levels beyond the completion of radiotherapy to determine whether tumor regrowth can be delayed. The antiangiogenic effects of SU11248 were demonstrated using human umbilical vein endothelial cells in vitro. Apoptosis increased and clonogenic survival decreased when SU11248 was used in combination with radiation from 0 to 6 Gy on endothelial cells. In vivo tumor growth delay was increased in C57B6J mice with Lewis lung carcinoma or glioblastoma multiform (GL261) hind limb tumors. Mice were treated with daily i.p. injections (40 mg/kg) of SU11248 during 7 days of radiation treatment (21 Gy). Combined treatment with SU11248 and radiation significantly reduced tumor volume as compared with either treatment alone. Concomitant reduction in vasculature was confirmed using the dorsal vascular window model. The vascular length established using images taken from a consistent quadrant in the window show the combination therapy was more effective in destroying tumor vasculature than either treatment alone. SU11248 maintenance administration beyond the completion of radiotherapy results in prolongation of tumor control. In summary, SU11248 enhances radiation-induced endothelial cytotoxicity, resulting in tumor vascular destruction and tumor control when combined with fractionated radiotherapy in murine tumor models. Moreover, inhibition of angiogenesis well beyond radiation therapy may be a promising treatment paradigm for refractory human neoplasms.     

A specific antagonist of the p110delta catalytic component of phosphatidylinositol 3'-kinase, IC486068, enhances radiation-induced tumor vascular destruction

The phosphatidylinositol 3'-kinase (PI3k)/protein kinase B (PKB/Akt) signal transduction pathway plays a critical role in mediating endothelial cell survival and function during oxidative stress. The role of the PI3k/Akt signaling pathway in promoting cell viability was studied in vascular endothelial cells treated with ionizing radiation. Western blot analysis showed that Akt was rapidly phosphorylated in response to radiation in primary culture endothelial cells (human umbilical vascular endothelial cells) in the absence of serum or growth factors. PI3k consists of p85 and p110 subunits, which play a central upstream role in Akt activation in response to exogenous stimuli. The delta isoform of the p110 subunit is expressed in endothelial cells. We studied the effects of the p110delta specific inhibitor IC486068, which abrogated radiation-induced phosphorylation of Akt. IC486068 enhanced radiation-induced apoptosis in endothelial cells and reduced cell migration and tubule formation of endothelial cells in Matrigel following irradiation. In vivo tumor growth delay was studied in mice with Lewis lung carcinoma and GL261 hind limb tumors. Mice were treated with daily i.p. injections (25 mg/kg) of IC486068 during 6 days of radiation treatment (18 Gy). Combined treatment with IC486068 and radiation significantly reduced tumor volume as compared with either treatment alone. Reduction in vasculature was confirmed using the dorsal skinfold vascular window model. The vascular length density was measured by use of the tumor vascular window model and showed IC486068 significantly enhanced radiation-induced destruction of tumor vasculature as compared with either treatment alone. IC486068 enhances radiation-induced endothelial cytotoxicity, resulting in tumor vascular destruction and tumor control when combined with fractionated radiotherapy in murine tumor models. These findings suggest that p110delta is a therapeutic target to enhance radiation-induced tumor control.     

白细胞介素-18对Lewis肺癌小鼠移植瘤生长及移植瘤细胞凋亡的作用

 目的 探讨IL-18对Lewis肺癌小鼠移植瘤生长及移植瘤细胞凋亡的作用。 方法 复制Lewis肺癌小鼠模型16只,随机分为IL-18治疗组与荷瘤模型组,每组8只,分别予IL-18、生理盐水于接种第7日起每日1次腹腔注射,连续7次。观察IL-18对小鼠健康状况、移植瘤变化的影响,并用TUNEL方法检测其对移植瘤细胞凋亡的作用。 结果 IL-18对小鼠健康状况无明显影响, 对移植瘤的生长有抑制作用,肿瘤抑制率为75%,对移植瘤细胞的凋亡有促进作用。 结论 IL-18可通过促进肿瘤细胞凋亡等途径对Lewis肺癌产生抑制作用,有望成为肺癌治疗的新策略。     

贝伐珠单抗诱导肿瘤血管正常化的时间窗及与紫杉醇联合治疗肺癌荷瘤鼠的实验研究

目的 探讨贝伐珠单抗诱导肿瘤血管正常化的时间窗及贝伐珠单抗联合紫杉醇对小鼠肺腺癌移植瘤的抑瘤效果。方法 选取成功构建的人肺腺癌A549裸鼠皮下移植瘤模型54只,实验分为两部分：第一部分荷瘤小鼠24只随机分为两组：对照组和贝伐珠单抗组各12只,分别腹腔注射生理盐水和贝伐珠单抗5 mg／kg,于给药后选取第1、3、5、8天共4个时间点,每个时间点各3只,测量瘤体体积及裸鼠体质量,采用Western blotting和免疫荧光法分别检测瘤体内血管内皮生长因子（VEGF）水平和微血管密度（MVD）。第二部分小鼠30只随机分为四组：对照组、紫杉醇单药组和贝伐珠单抗单药组各5只及联合组15只。联合组于贝伐珠单抗给药当天及给药后第3、5天各选取5只腹腔注射紫杉醇,紫杉醇和贝伐珠单抗的剂量分别为3 mg／kg和5 mg／kg,于给药后选取第3、7、10、14、17、20天共6个时间点测量瘤体体积,21天后处死裸鼠称取瘤体质量,采用Western blotting和免疫组化法分别检测瘤体VEGF水平和MVD。结果 在第一部分实验中,与对照组相比,贝伐珠单抗组给药后肿瘤的生长得到抑制,以第三天抑制效应最显著,此时瘤体的体积最小,瘤体内VEGF含量表达减少,瘤体MVD也相应减少。在第二部分实验中,与对照组相比,贝伐珠单抗不同时间点联合紫杉醇给药均可显著抑制肿瘤生长,以贝伐珠单抗联合紫杉醇第三天给药组抑制效应更为显著,且瘤体的体积、质量、VEGF含量及MVD均较其他联合给药组少。结论 贝伐珠单抗诱导的血管正常化时间窗可能在给药后第1～3天,在该时间窗内联合紫杉醇可达到最大的抗肿瘤效应。     

Antitumor and vascular effects of apatinib combined with chemotherapy in mice with non-small-cell lung cancer

Objective The aim of this study was to investigate the antitumor and vascular effects of apatinib use combined with chemotherapy on mice with non-small-cell lung cancer (NSCLC). Methods First, 60 tumor-bearing nude mice were randomly divided into control, low-dose, and high-dose groups. Four nude mice per group were sacrificed before administration and on days 1, 3, 7, and 10 after administration. HIF-1α expression in tumor tissues was detected. Second, 32 nude mice were randomly divided into control, premetrexed, synchronous, and sequential groups. The weights and tumor volumes of mice were recorded. Results (1) HIF-1α expression decreased significantly on days 3 and 7 after low-dose apatinib treatment. There was no significant difference in HIF-1α expression in the high-dose apatinib group (P > 0.05). MMP-2 and MMP-9 expression levels in the low-dose apatinib group were significantly lower than those in the control group (P < 0.05). (2) In the low-dose apatinib group, the microvessel density increased gradually from days 3 to 7 post-treatment, while that in the high-dose apatinib group decreased significantly. (3) The inhibitory effect of sequential therapy using low-dose apatinib and pemetrexed was optimal, while that of synchronous treatment was not better than that of pemetrexed usage alone. Sequential treatment using low-dose apatinib and pemetrexed exerted the best antitumor effect. (4) The expression levels of p-AKT, p-mTOR, p-MEK, and p-ERK in the sequential group were significantly lower than those in the other three groups (P < 0.05). Conclusion Apatinib usage involves certain considerations, such as dose requirements and time window for vascular normalization during lung cancer treatment in nude mice, suggesting that dynamic contrast-enhanced magnetic resonance imaging and other tests can be conducted to determine the vascular normalization window in patients with lung cancer and to achieve the optimal anti-vascular effect.     

Radiation improves the distribution and uptake of liposomal doxorubicin (caelyx) in human osteosarcoma xenografts

Liposomal drug delivery appears to improve the antitumor effect and reduce toxicity compared with the free drug. The therapeutic index may be improved further by combining cytotoxic drugs and radiotherapy. Successful therapy requires that the cytotoxic agents reach the tumor cells. Therefore, we studied tumor growth and the microdistribution of liposomal doxorubicin (Caelyx) with and without additional ionizing radiation in human osteosarcoma xenografts in athymic mice. Caelyx was injected i.v. 1 day before single or fractionated radiotherapy. Both chemoirradiation regimens induced significant tumor growth delays and worked synergistically. Confocal laser scanning microscopy showed that intact liposomes were located in close proximity to endothelial cells, and the distribution of released doxorubicin was heterogeneous. Before radiotherapy, hardly any doxorubicin was localized in the central parts of the tumor. Radiotherapy increased the tumor uptake of doxorubicin by a factor of two to four, with drug being redistributed farther from the vessels in the tumor periphery and located around vessels in the central parts of the tumor. Colocalization of doxorubicin and hypoxic cells showed no distribution of drug into hypoxic areas. Dynamic contrast-enhanced magnetic resonance imaging (MRI) 1 day before the injection of Caelyx and 2 days after treatment start showed that the combined treatment reduced the vascular volume and the vascular transfer rate of the MRI tracer. The results show that chemoirradiation with Caelyx induces synergistic treatment effects. Improved intratumoral drug uptake and distribution are responsible to some extent for the enhanced antitumor effect.     

IL-18对Lewis肺癌小鼠移植瘤生长的抑制作用

目的：观察IL-18对Lewis肺癌小鼠移植瘤生长的抑制作用。方法：建立Lewis肺癌小鼠皮下移植瘤模型16只，按随机数字法分为IL-18治疗组、荷瘤模型组，每组8只，分别给予IL-18、生理盐水于接种第7日起腹腔注射。观察IL-18对移植瘤体积变化及瘤重的影响。结果：IL-18对小鼠健康状况无明显影响，但对小鼠移植瘤生长有明显抑制作用，肿瘤抑制率为75％。结论：IL-18可抑制Lewis肺癌小鼠移植瘤的生长，其机制值得深入研究。     

Thrombospondin-1 and pigment epithelium-derived factor enhance responsiveness of KM12 colon tumor to metronomic cyclophosphamide but have disparate effects on tumor metastasis

The anti-tumor activity, metronomic chemotherapy sensitization potential and metastatic effects of the endogenous angiogenesis inhibitors thrombospondin-1 and PEDF were investigated in KM12 colon adenocarcinoma xenografts. Thrombospondin-1 and PEDF decreased KM12 tumor microvessel density, increased macrophage infiltration, and improved responsiveness to metronomic cyclophosphamide (CPA) treatment, but did not activate the anti-tumor innate immunity that metronomic CPA induces in other tumor models. Moreover, thrombospondin-1, but not PEDF, significantly increased KM12 metastasis to the lung, while PEDF augmented the anti-metastatic activity of metronomic CPA. Thus, while thrombospondin-1 and PEDF both increase the KM12 tumor responsiveness to metronomic CPA, they have disparate effects on tumor metastasis.