Combination of flavone acetic acid (FAA) with adriamycin,cis-platinum and difluoromethylornithine (DFMO) in vitro against human colon cancer cells

Summary Unresectable solid tumors in the metastatic stage are quite resistant to current chemotherapy and radiation therapy regimens. Flavone acetic acid (FAA) is a novel antitumor agent which appears to work through a different mechanism than the conventional chemotherapeutic agents. In preclinical studies it has shown effectiveness against a variety of transplantable murine and human tumors and appears to be solid tumor selective. It also has non-overlapping toxicities as compared to conventional agents. We therefore investigated FAA in vitro against human colon cancer cells and explored whether its effectiveness could be enhanced in combination with other agents such as adriamycin (ADR), cis-platinum (CP) and difluoromethyornithine (DFMO) — an inhibitor of polyamine biosynthesis. Addition of FAA for 24 hours in liquid media produced dose dependent growth inhibition. Using soft agar colony assay, growth was inhibited by 58% by 3mM FAA and only 1.4% by 0.375mM FAA. The combination of FAA and cis-platinum produced synergism at the lower doses tested. The combination of FAA and adriamycin produced antagonism at all doses tested and the combination of FAA with DFMO did not produce results significantly different from DFMO alone. We conclude that enhancement of FAA activity can be achieved in combination with conventional antitumor agents, but may be drug and dose specific.     

乳癌病人单次卡铂和阿霉素化疗诱发的染色体损伤和细胞生物学毒性

应用常规染色体畸变分析和胞浆分裂阻滞微核（ｃｙｔｏｋｉｎｅｓｉｓｂｌｏｃｋｍｉｃｒｏｎｕｃｌｅｉ，ＣＢＭＮ）法对１０例接受单次卡铂（平均剂量为４６２．９ｍｇ／ｍ２）和单次阿霉素（平均剂量为４８．１ｍｇ／ｍ２）化疗的乳癌病人血样进行了淋巴细胞染色体畸变（ｃｈｒｏｍｏｓｏｍｅａｂｅｒａｔｉｏｎ，ＣＡ）和微核（ｍｉｃｒｏｎｕｃｌｅｉ，ＭＮ）的观察分析，并通过有丝分裂指数（ｍｉｔｏｔｉｃｉｎｄｅｘ，ＭＩ）及核分裂指数（ｎｕｃｌｅａｒｄｉｖｉｓｉｏｎｉｎｄｅｘ，ＮＤＩ）观测了细胞毒性。结果表明，单次卡铂和阿霉素化疗均引起了ＣＡ和ＭＮ显著性增加，所观察到的ＣＡ主要为单体畸变，其中单体间隙（ｃｈｒｏｍａｔｉｄｇａｐ，ｃｔｇ）的增加最为显著，染色体型畸变未见显著性变化；卡铂引起ＭＩ明显减低，阿霉素对ＭＩ的影响不显著；两种化疗药物均未对ＮＤＩ产生显著性影响；通过ＭＩ及ＮＤＩ测量的细胞毒性之间显著性相关，但ＣＡ分析和ＣＢＭＮ法测得的染色体损伤之间缺乏相关性。     

Anthracycline-induced cardiotoxicity: Overview of studies examining the roles of oxidative stress and free cellular iron

The risk of cardiotoxicity is the most serious drawback to the clinical usefulness of anthracycline antineoplastic antibiotics, which include doxorubicin (adriamycin), daunorubicin or epirubicin. Nevertheless, these compounds remain among the most widely used anticancer drugs. The molecular pathogenesis of anthracycline cardiotoxicity remains highly controversial, although the oxidative stress-based hypothesis involving intramyocardial production of reactive oxygen species (ROS) has gained the widest acceptance. Anthracyclines may promote the formation of ROS through redox cycling of their aglycones as well as their anthracycline-iron complexes. This proposed mechanism has become particularly popular in light of the high cardioprotective efficacy of dexrazoxane (ICRF-187). The mechanism of action of this drug has been attributed to its hydrolytic transformation into the iron-chelating metabolite ADR-925, which may act by displacing iron from anthracycline-iron complexes or by chelating free or loosely bound cellular iron, thus preventing site-specific iron-catalyzed ROS damage. However, during the last decade, calls for the critical reassessment of this “ROS and iron” hypothesis have emerged. Numerous antioxidants, although efficient in cellular or acute animal experiments, have failed to alleviate anthracycline cardiotoxicity in clinically relevant chronic animal models or clinical trials. In addition, studies with chelators that are stronger and more selective for iron than ADR-925 have also yielded negative or, at best, mixed outcomes. Hence, several lines of evidence suggest that mechanisms other than the traditionally emphasized “ROS and iron” hypothesis are involved in anthracycline-induced cardiotoxicity and that these alternative mechanisms may be better bases for designing approaches to achieve efficient and safe cardioprotection.     

阿霉素不同剂量静脉注射的药动学及其临床意义

采用ＨＰＬＣ法测定１４例肿瘤患者使用不同剂量阿霉素的血药浓度，并计算药代参数。４０ｍｇ／ｍ２和２５ｍｇ／ｍ２两组的血药峰浓度、ＡＵＣ、Ｖｃ差异有显著性。阿霉素的药代动力学存在明显的个体差异，血药峰浓度、Ｖｃ、Ｋ１２与疗效相关。     

高脂饲料加重大鼠阿霉素肾病的实验病理学研究

探讨高脂饲料加剧阿霉素肾病大鼠高脂血症及肾组织形态学改变的作用。用ＡＤＲ静脉注射建立大鼠肾病模型，饲喂含１．５％胆固醇、５％猪油的高脂饲料，观察大鼠尿蛋白排泄量，测定血肖中脂质有关指标以及检查肾组织形态学改变。饲喂高脂饲料的ＡＤＲ肾病大鼠，血清脂质水平在整个试验过程中均明显高于饲喂基础饲料的ＡＤＲ肾病大鼠，肾小球病变也显著加重，饲喂高脂饲料所致高脂血症是导致大鼠ＡＤＲ肾病进行性进展的重要因素之一。     

Results of a randomized study of early stage Hodgkin's disease using ABVD,EBVD, or MBVD

From January 1986 to December 1989, 157 previously untreated patients, with Hodgkin's disease stage I or II without bulky disease, were enrolled in a clinical comparative study. The objectives of the study were to compare the efficacy and safety of using epirubicine or mitoxantrone instead of adriamycin in the combination chemotherapy regimen ABVD (adriamycin, bleomycin, vinblastine, and dacarbazine). The complete response rate was better in the patients treated with the ABVD or EBVD regimens compared to the MBVD arm. Also, differences in overall survival and relapse-free survival were better in the patients who received ABVD or EBVD compared to the MBVD regimen. Hematological, gastrointestinal and cardiac toxicity were similar in the three groups. Dose intensity, delays and complications were also similar in the three groups. The mitoxantrone-containing regimen was found to have less efficacy in comparison to the other regimens tested in the present study in patients with favorable stage I or II Hodgkin's disease. © 1995 Wi1ey-Liss Inc.     

聚维酮联合阿霉素体外抑制膀胱癌细胞T24生长并预防膀胱癌患者术后复发

目的探讨聚维酮(PVP)联合阿霉素(ADM)对人膀胱癌细胞株T24的作用及预防膀胱癌术后复发的疗效。方法MTT法检测细胞生长抑制率,流式细胞仪检测细胞周期和黏附作用。对231例浅表膀胱癌患者术后膀胱灌注PVP ADM(实验组)或生理盐水 ADM(对照组),观察预防复发效果。结果2·5%PVP作用24h和72h细胞生长抑制率为15·11%和49·57%;7·5%浓度时,抑制率升为35·42%和79·66%。单用0·25mg/LADM作用48h抑制率为39·05%;合用2·5%和7·5%PVP抑制率升为68·51%和88·39%。5%PVP能使T24细胞的G0/G1期比率下降和G2/M期比率上升。PVP能提高抗鼠IgG1对T24细胞的黏附作用。194例患者获随访,实验组复发率明显降低,复发时间明显延长(均P<0·01)。结论PVP通过阻滞细胞周期G2/M期和增强黏附作用来抑制T24细胞生长,与ADM联合具有协同作用。PVP联合ADM膀胱灌注预防浅表膀胱癌术后复发疗效确切,副作用少。     

Thermal gradients in microtitration plates. Effects on enzyme-linked immunoassay

Temperature studies of microtitration plates demonstrate that the use of a common bacteriology incubator for heating the plates can cause a phase lag of over 30 min for the fluid in the wells to reach 37°C from ambient temperature, and that a temperature gradient of as much as 1.6°C can exist between the peripheral and center wells. This gradient is a cause of the ‘rim’ or edge effect noted in enzyme immunoassay using microtitration plates. The problem is corrected by the use of a specially designed forced air microtitration plate incubator.     

Modulation of osteopontin in proteinuria-induced renal interstitial fibrosis

Proteinuria is associated with macrophage-dependent interstitial fibrosis (IF). Osteopontin (OPN), a macrophage chemoattractant, may be involved in the transition of proteinuria to IF but protective properties have also been reported. To elucidate whether OPN may be involved in the proteinuria-induced cascade of tubulointerstitial damage, renal expression of OPN was studied during the development of proteinuria-induced renal damage and during anti-proteinuric intervention with ACE inhibition (ACEi). First, the temporal relationships between proteinuria, interstitial OPN induction, and IF in adriamycin nephrosis (AN), a model of chronic proteinuria-induced renal damage, were studied. Second, the effect of anti-proteinuric treatment on OPN expression was investigated. The time course of OPN induction and markers of renal damage was studied in rats with unilateral AN at 6-week intervals until week 30. In a second study, a renal biopsy was taken 6 weeks after induction of bilateral AN; subsequently, rats were treated with ACEi until termination (week 12). In unilateral AN, proteinuria developed gradually and stabilized at week 10. In proteinuric kidneys, OPN expression was induced from week 12 onwards. Simultaneously, a progressive increase in interstitial macrophages, alpha-smooth muscle actin (alpha-SMA), collagen type III, and focal glomerulosclerosis (FGS) was observed. In bilateral AN, ACEi reduced proteinuria and OPN protein and stabilized fibrosis. In untreated animals, OPN mRNA increased, with stable OPN protein and fibrosis and increased FGS. Thus, in AN, development of proteinuria is followed by up-regulation of OPN along with markers of renal damage. The up-regulation of OPN is reversible by anti-proteinuric treatment without a corresponding reduction in fibrosis. Whereas these data are consistent with a role for OPN in the cascade of transition from proteinuria to fibrosis, intervention with ACEi showed that reduction of OPN does not attenuate established fibrosis.     

阿霉素性心肌病之心肌线粒体酶的细胞化学研究

阿霉素性心肌病之心肌线粒体SDH和CCO的细胞化学观察发现,多数线粒体的酶活性较弱,少数较强或中等,并与ADR的累积用量和心肌损伤程度有关。作者认为SDH和CCO活性降低,线粒体能量代谢障碍在ADR引起心肌病的过程中起着重要作用。