噬菌体随机12肽库筛选肝癌患者血清肿瘤标记物的初步研究

目的：从噬菌体随机多肽文库中,筛选出能与肝癌患者血清特异性结合的短肽分子.方法：采用肝癌患者血清作为配基,筛选以融合蛋白形式在丝状噬菌体M13外壳蛋白Ⅲ表达的随机12肽文库.按吸附一洗脱一扩增的淘筛过程,经3轮淘筛后,随机挑取噬菌体克隆用ELISA检测其特异性,评价分析其诊断肝癌的价值.结果：经3轮淘筛后,特异性结合的噬菌体富集增加近100倍.用.ELISA检测第3轮筛选后随机挑取的单个噬菌体克隆,其中特异性最好的3个克隆具有诊断肝癌的潜在价值.结论：噬菌体展示肽库技术,可以有效进行肝癌相关抗原肽的筛选研究,为获得特异性诊断试剂进而为肝癌的诊断提供依据.     

噬菌体肽库在宫颈癌血清肿瘤标志物筛选中的应用

目的:用噬菌体随机12肽库对宫颈癌患者血清进行差异性筛选,筛选出能与宫颈癌患者血清特异性结合的肿瘤标志物。方法:应用噬菌体随机12肽库对宫颈癌患者和正常人血清进行三轮差异性筛选,用ELISA法检测噬菌体克隆对宫颈癌患者血清结合的特异性。结果:经过三轮筛选,噬菌体富集率逐轮提高,提高近100倍。用ELISA法对50例宫颈癌患者血清和50例健康者血清检测验证,其中获得一株与宫颈癌患者血清特异结合较好的噬菌体,对宫颈癌的早期诊断具有潜在价值。结论:筛选出能与早期宫颈癌患者血清高亲和力特异结合的短肽,为研究宫颈癌肿瘤标志物及宫颈癌的早期诊断奠定了基础。     

MDA-MB-231乳腺癌细胞特异性多肽的初步筛选

目的 利用噬菌体展示技术,从噬菌体随机十二肽库中筛选出能够特异性结合MDA-MB-231乳腺癌细胞的噬菌体克隆.方法 以人正常乳腺细胞为减性筛选细胞、MDA-MB-231乳腺癌细胞为靶细胞,对噬菌体随机十二肽库进行筛选,挑取富集后的阳性单克隆噬菌体,酶联免疫吸附试验（ELISA）及DAB染色鉴定阳性噬菌体的特异性及亲和力.结果 经过3轮筛选,噬菌体得到约113倍的富集,随机挑选11株单克隆噬菌体,ELISA显示8号噬菌体单克隆对乳腺癌细胞的亲和力是对照的6.5倍,DAB鉴定亦显示其对乳腺癌细胞的特异性及亲和力最高,命名为LK-8.结论 利用噬菌体筛选技术成功筛选出能够特异性结合MDA-MB-231乳腺癌细胞的特异性噬菌体单克隆LK-8,可为进一步合成特异性多肽用于早期诊断和靶向治疗乳腺癌奠定基础.     

宫颈癌HeLa细胞特异性结合肽的筛选及鉴定

背景与目的:宫颈癌的分子靶向治疗具有很好的疗效,同时可以显著减少抗癌药物对人体自身的损伤,因此备受关注。本研究利用噬菌体体内展示技术筛选及鉴定宫颈癌特异性结合肽,将有可能成为化疗药物的靶向载体,为宫颈癌靶向药物治疗奠定基础。方法:体外培养宫颈癌HeLa细胞接种裸鼠,建立肿瘤动物模型。将随机肽库尾静脉注入裸鼠体内,循环15 min,心脏灌注后回收肿瘤组织噬菌体扩增、纯化并以此作为起始物进行第2轮的筛选,如此进行3轮体内筛选后挑取噬菌体克隆,进行免疫组化及ELISA实验,初步鉴定噬菌体克隆对宫颈癌细胞的亲和力及特异性,并将具有强亲和力的克隆进行测序。结果:ELISA结果显示,随机挑选10个噬菌体单克隆中8个克隆对HeLa细胞具有很强的亲和力,将这8个克隆进行测序,获得相同短肽序列LLRSTGF。结论:利用噬菌体展示技术筛选出与宫颈癌细胞HeLa特异性结合的短肽,进一步与化疗药物结合,为宫颈癌靶向治疗提供新的方法。     

随机十二肽噬菌体展示文库筛选血型B抗原模拟多肽的实验研究

目的:筛选出替代血型B抗原的模拟多肽,用多肽抗原替代糖类抗原.方法:抗血型B抗原的单克隆抗体作为固相筛选靶分子,对随机十二肽噬菌体展示文库进行生物淘选(bio-panning),经包被-结合-洗脱-扩增等循环3轮,对筛选的克隆ELISA鉴定,并通过剂量依赖实验验证其结合特异性.最后提取DNA测序,确定模拟肽氨基酸序列.结果:3轮筛选结束,得到2个亲和力较强的十二肽序列TKNMLSL-PVGPG和HSLKHTQMSYSS.结论:经过生物筛选得到模拟多肽序列,利用噬菌体展示技术筛选糖类抗原的模拟肽具有可行性,为糖类抗原的研究提供一种新思路.     

胃癌SGC7901细胞特异性结合肽的筛选及鉴定

目的筛选与人胃癌细胞株SGC7901特异性亲和的短肽,提高胃癌治疗的针对性。方法建立裸鼠胃癌模型,将噬菌体随机环7肽文库通过尾静脉注射入裸鼠体内,每轮筛选后测噬菌体效价。采用免疫组化及ELISA等方法,对目标噬菌体进行检测,提取噬菌体DNA,进行序列测定。结果经过4轮筛选,噬菌体在胃癌肿瘤组织中得以明显富集。免疫组化结果显示肿瘤组织为强阳性。ELISA结果显示:随机挑选的13个克隆中12个对SGC7901细胞的亲和力高。序列测定结果:PPRWMPS出现的次数最多。结论提示短肽PPRWMPS可能对荷瘤裸鼠模型的胃癌组织具有很强地结合力,有望成为胃癌治疗的靶点。     

利用体内噬菌体展示技术筛选肝癌组织特异性结合肽

目的 筛选人源肝癌组织特异性结合短肽。方法 体外培养人源肝癌细胞株BEL-7402,建立荷瘤裸鼠模型。尾静脉注射噬菌体12肽文库至荷瘤裸鼠体内,循环20min后回收肿瘤组织中噬菌体,同时取正常对照组织进行噬菌体效价测定和免疫绀化观察。将同收的噬菌体扩增、纯化,并以此作为起始物进行下一轮筛选。经过3轮体内筛选,得到与肝癌组织或细胞特异结合的肽段。随机挑选噬菌体单克隆进行测序,分析序列㈣源性后进行体外细胞酶联免嫂吸附试验（ELISA）和体内回输实验,验证噬菌体克隆的导向性。结果 经过3轮体内筛选,瘤组织中噬菌体的回收率逐步提高,回收量随着输入量的增加迅速增加,而每轮筛选肝组织中的噬菌体回收晕始终保持在一个恒定范围,并不随输入量的增加而增加。免疫组化结果硅示,第3轮筛选后,瘤组织中的噬菌体得到高水平富集,同时其他组织的非特异性结合降至最低,肝癌细胞特异性结合最强的是A54号单克降,A67、B2号单克隆次之。B2的导向效果最好,A54次之。通过对噬菌体单克隆的序列分析,初步确定了PSS／FTT基序。结论 利用体内噬菌体展示技术,可以成功筛选到与肝癌细胞或组织特异结合的噬菌体肽。     

抗内毒素噬菌体抗体库的构建及筛选

目的构建一个鼠源性的抗内毒素单链噬菌体抗体库,从中筛选出对内毒素具有较高亲和力的单链抗体。方法从小鼠脾细胞中提取总RNA,通过RT-PCR技术扩增出小鼠抗体重链、轻链可变区基因（VH,VL）,用Linker将VH,VL交联形成单链抗体可变区片段（ScFv）。经NotⅠ,SfiⅠ双酶切后与经同样双酶切的pCANTAB5E载体相连,转化入大肠杆菌TG1以构建鼠抗内毒素单链噬菌体抗体库。在援救噬菌体抗体库后,用内毒素淘筛特异性的ScFv,富集的噬菌体阳性克隆重新感染TG1。在96孔板分别援救单个含特异性ScFv的TG1菌落,最后随机挑选出190个菌落经ELISA检测抗内毒素ScFv。结果小鼠血清中抗内毒素的效价为1∶12800。提取的总RNA浓度为12.3813μg/ml,纯度较好。扩增出的VH长约340bp,VL约320bp,ScFv约800bp。转化入TG1后有约1.9×107个菌落。淘筛一轮过后即有3×104阳性菌落长出,190个菌落经ELISA检测有2个阳性克隆。结论成功地构建了一个库容量为1.9×107的鼠抗内毒素单链噬菌体抗体库,并从中筛选出了2株抗内毒素ScFv。     

胃癌细胞特异性结合肽的筛选及鉴定

目的 筛选与胃癌细胞特异性结合的多肽。方法 以正常细胞为吸附细胞,胃癌细胞为筛选靶细胞对噬菌体随机12肽库进行消减筛,用细胞酶联免疫吸附试验（ELISA）、免疫细胞和组织化学法及裸鼠正常组织结合实验鉴定阳性克隆并进行DNA测序。结果 经三轮筛选,利用ELISA从随机挑选的24个噬菌体克隆中得到8个与胃癌细胞具有高结合力的噬菌体阳性克隆,经免疫细胞化学及裸鼠正常组织结合试验鉴定,发现第20、24两个克隆能与胃癌细胞特异性结合,而不与正常细胞和裸鼠组织结合,噬菌体阳性克隆氨基酸序列无同源性。结论 得到两个序列不同的特异性结合胃癌细胞的噬菌体克隆,这可为进一步的研究提供实验依据。     

应用噬菌体随机肽库筛选肿瘤MUC1/Y黏蛋白结合肽

目的：探索用噬菌体随机肽库筛选可用于肿瘤导向治疗的新型小分子载体。方法：以MUC1/Y黏蛋白的胞外段蛋白（MUC1/Yex）为靶分子,用凝胶亲和法和酶联板法分别筛选十二肽噬菌体随机肽库,ELISA鉴定阳性克隆,DNA序列测定后确定MUC1/Yex结合肽的氢基酸序列;免疫组化鉴定阳性噬菌体克隆及正常及肿瘤细胞的结合能力及特异 性。结果：通过4轮筛选,共获得3种MUC1/Yex的结合肽,分别为HHWHSRSQLSWF,HLKHKNYLPPTP和GNWYRHPHYLQP,其中HXXHS表位可能在与MU1/Yex的结合中起重要作用。阳性噬菌体克隆可与肿瘤细胞系MCF7,OVCA3,而不与正常外周血淋巴细胞结合。结论：筛选获得的MUC1/Yex结合肽具有一定的亲合力和肿瘤特异性,可进一步用于肿瘤导向治疗的研究。     

Experience with Impedance Phlebography Compared with Venography

Venography is a particularly reliable method for the diagnosis of deep venous thrombosis but is not suitable as a screening test. Impedance phlebography represents another attempt to discover a simple, non-invasive and reliable method of detecting deep venous thrombosis. It does not, however, meet these criteria.     

Compliance with guidelines and correlation with outcome in patients with advanced germ-cell tumours

PurposeTo evaluate prior compliance with guidelines in patients treated with salvage chemotherapy for advanced germ-cell tumours (GCT).Patients and methodsData concerning the initial management of patients requiring salvage chemotherapy for GCT at Institut Gustave Roussy between 2000 and 2010 were obtained and correlated with recommendations for treatment. Criteria of non-compliance were defined based on guidelines. Compliance with guidelines, predictive factors for non-compliance and the impact on outcome were analysed.ResultsAmong 82 patients treated in the salvage setting, guidelines to initial treatment were followed in only 41 cases (50%). The most common non-compliance criteria were non-adherence to the planned dose (16%), an inappropriate interval between first-line chemotherapy cycles (16%), the lack of post-chemotherapy surgery (16%) and a long interval to post-chemotherapy surgery (48%). Compliance with standard care was better in cancer centres than in other hospitals (private or public) (Odd Ratio (OR): 6.9, P = 0.001). A poor-risk status according to the International Germ Cell Cancer Collaborative Group (IGCCCG) was also predictive of compliance in univariate but not in multivariate analysis. No significant difference in outcome after salvage chemotherapy was observed. Patients relapsing after non-compliant first-line therapy tended to be more easily salvaged, which is consistent with the fact that their initial treatment was inadequate. Some of these relapses were therefore probably not due to true biologically refractory disease.ConclusionGuidelines for first-line treatment are adhered to in only half the patients requiring salvage chemotherapy. As the only predictive factor for non-compliance was the treating centre, centralisation of patients with GCT in well-trained hospitals should be recommended.     

Treatment with methylnaltrexone is associated with increased survival in patients with advanced cancer

BackgroundMethylnaltrexone (MNTX), a peripherally acting μ-opioid receptor (MOR) antagonist, is FDA-approved for treatment of opioid-induced constipation (OIC). Preclinical data suggest that MOR activation can play a role in cancer progression and can be a target for anticancer therapy.Patients and methodsPooled data from advanced end-stage cancer patients with OIC, despite laxatives, treated in two randomized (phase III and IV), placebo-controlled trials with MNTX were analyzed for overall survival (OS) in an unplanned post hoc analysis. MNTX or placebo was given subcutaneously during the double-blinded phase, which was followed by the open-label phase, allowing MNTX treatment irrespective of initial randomization.ResultsIn two randomized, controlled trials, 229 cancer patients were randomized to MNTX (117, 51%) or placebo (112, 49%). Distribution of patients' characteristics and major tumor types did not significantly differ between arms. Treatment with MNTX compared with placebo [76 days, 95% confidence interval (CI) 43–109 versus 56 days, 95% CI 43–69; P = 0.033] and response (laxation) to treatment compared with no response (118 days, 95% CI 59–177 versus 55 days, 95% CI 40–70; P < 0.001) had a longer median OS, despite 56 (50%) of 112 patients ultimately crossing over from placebo to MNTX. Multivariable analysis demonstrated that response to therapy [hazard ratio (HR) 0.47, 95% CI 0.29–0.76; P = 0.002) and albumin ≥3.5 (HR 0.46, 95% CI 0.30–0.69; P < 0.001) were independent prognostic factors for increased OS. Of interest, there was no difference in OS between MNTX and placebo in 134 patients with advanced illness other than cancer treated in these randomized studies (P = 0.88).ConclusionThis unplanned post hoc analysis of two randomized trials demonstrates that treatment with MNTX and, even more so, response to MNTX are associated with increased OS, which supports the preclinical hypothesis that MOR can play a role in cancer progression. Targeting MOR with MNTX warrants further investigation in cancer therapy.Clinical trials numberNCT00401362, NCT00672477.     

Costs associated with complications are lower with capecitabine than with 5‐fluorouracil in patients with colorectal cancer

BACKGROUND:

Capecitabine, an oral alternative to 5‐fluorouracil (5‐FU) in patients with colorectal cancer (CRC), has equal clinical efficacy and a favorable safety profile; however, its use may be limited because of unit cost concerns. In this study, the authors measured the cost of chemotherapy‐related complications during treatment with capecitabine‐ and 5‐FU–based regimens.

METHODS:

Patients with CRC who received at least 1 administration of capecitabine or 5‐FU during 2004 and 2005 were identified from the Thomson MarketScan research databases. Monthly frequency and cost for 23 complications were recorded. Logistic regression was used to predict complication probability. General linear models were used to predict monthly complication cost and total monthly expenditure.

RESULTS:

In total, 4973 patients with CRC met the inclusion criteria for this analysis. Although the most frequently observed complications were the same between capecitabine and 5‐FU (nausea and vomiting, infection, anemia, neutropenia, diarrhea), each was observed with greater frequency in 5‐FU–based regimens. The mean predicted monthly complication cost was significantly higher (by 136%) with 5‐FU monotherapy than with capecitabine monotherapy (difference, $601; 95% confidence interval [95% CI], $469‐$737). In addition, the mean predicted monthly complication cost for 5‐FU+oxaliplatin was higher than the cost with capecitabine plus oxaliplatin (difference, $1165; 95% CI, $892‐$1595). When acquisition, administration, and complication costs were taken into consideration, there were no significant differences in the total cost between capecitabine regimens and 5‐FU regimens.

CONCLUSIONS:

Capecitabine compared well with 5‐FU–based therapy in patients with CRC and was associated with lower complication rates and associated costs. Cancer 2009. © 2009 American Cancer Society.     

Living with secondary breast cancer: coping with an uncertain future with unmet needs

JOHNSTON S.R.D. (2010) European Journal of Cancer Care 19 , 561–563 Living with secondary breast cancer: coping with an uncertain future with unmet needs     

奥沙利铂联合羟基喜树碱治疗晚期胃癌临床分析

背景与目的体外及体内的临床研究显示,奥沙利铂(L-OHP)对多种肿瘤有显著抑制作用并与绝大多数抗癌药物具有相加或协同细胞毒作用.本文旨在观察L-OHP联合羟基喜树碱(HCPT)治疗晚期胃癌的近期疗效和患者耐受性,并与传统的化疗方案进行对比.方法采用非随机的分组方法将43例晚期胃癌患者分为L-OHP+HCPT方案组(治疗组)与Vp-16+CF+5-FU(ELF)方案组(对照组),其中男性28例,女性15例,中位年龄59岁,KPS评分≥60,观察两组的近期疗效和患者耐受性.结果治疗组24例有效率58.3%(14/24),对照组19例有效率42.1%(8/19).治疗组有效率高于对照组,两组差异有显著性(P<0.05).两组不良反应主要是骨髓抑制、恶心、呕吐、口腔炎、周围神经炎、静脉炎、脱发等,均在Ⅰ、Ⅱ度范围内.结论L-OHP联合HCPT方案治疗晚期胃癌疗效较好,不良反应可以耐受.     

Varicella-Zoster Virus Prophylaxis with Low-Dose Acyclovir in Patients with Multiple Myeloma Treated with Bortezomib

BackgroundVaricella-zoster virus (VZV) reactivation is a common complication in patients with multiple myeloma (MM) treated with bortezomib, with an incidence rate of 10%-60%. The aim of our study was to analyze the effect of acyclovir prophylaxis in this patient population.Patients and MethodsWe studied 98 consecutive patients with relapsed MM treated with bortezomib. Bortezomib 1.3 mg/m² was given on days 1, 4, 8, and 11 of a 21-day cycle. At first, patients did not receive any VZV prophylaxis, but because of the high incidence of VZV reactivation, VZV prophylaxis with acyclovir was implemented subsequently.ResultsA total of 11 patients treated with bortezomib did not have any VZV prophylaxis, and 4 of these 11 patients (36%) developed VZV reactivation in the form of herpes zoster. No VZV reactivations were observed in the 32 patients who received acyclovir 400 mg 3 times daily or the 55 patients who received acyclovir in a dose reduced to 400 mg once daily during bortezomib treatment.ConclusionVaricellazoster virus reactivation is a common and serious adverse effect of bortezomib treatment. Acyclovir 400 mg once daily is sufficient to protect from VZV reactivation in patients with MM treated with bortezomib.