多西他赛作为一线用药治疗卵巢癌研究进展

多西他赛是半合成的紫杉类药物,临床药理学研究证实,多西他赛的抗瘤活性强于紫杉醇,并和紫杉醇没有交叉耐药.已有的研究表明,多西他赛治疗铂类耐药和对紫杉醇耐药的卵巢癌有较好的疗效.近几年,很多研究评价了多西他赛作为一线药物治疗卵巢上皮癌的价值.Ⅰ期和Ⅱ期的临床研究证实,多西他赛联合铂类药物作为一线药物治疗卵巢癌有较好的有效率为58%～89%,而多西他赛联合卡铂化疗的毒副反应比多西他赛联合顺铂少,特别是神经毒性.Ⅲ期临床研究比较了多西他赛联合卡铂方案和目前作为治疗卵巢上皮癌标准一线化疗方案的紫杉醇联合卡铂方案治疗卵巢上皮癌的差别,发现两个方案有相同的有效率,分别为58.7%和59.5%,但是多西他赛联合卡铂化疗的神经毒性更低,所以推荐多西他赛加卡铂联合化疗方案作为卵巢上皮癌的一线化疗方案.     

多西他赛作为一线用药治疗卵巢癌研究进展

多西他赛是半合成的紫杉类药物,临床药理学研究证实,多西他赛的抗瘤活性强于紫杉醇,并和紫杉醇没有交叉耐药。已有的研究表明,多西他赛治疗铂类耐药和对紫杉醇耐药的卵巢癌有较好的疗效。近几年,很多研究评价了多西他赛作为一线药物治疗卵巢上皮癌的价值。Ⅰ期和Ⅱ期的临床研究证实,多西他赛联合铂类药物作为一线药物治疗卵巢癌有较好的有效率为58%～89%,而多西他赛联合卡铂化疗的毒副反应比多西他赛联合顺铂少,特别是神经毒性。Ⅲ期临床研究比较了多西他赛联合卡铂方案和目前作为治疗卵巢上皮癌标准一线化疗方案的紫杉醇联合卡铂方案治疗卵巢上皮癌的差别,发现两个方案有相同的有效率,分别为58.7%和59.5%,但是多西他赛联合卡铂化疗的神经毒性更低,所以推荐多西他赛加卡铂联合化疗方案作为卵巢上皮癌的一线化疗方案。     

肿瘤免疫治疗和化疗的协同效应及其作用机制

近年来肿瘤治疗领域受到关注的热点之一是免疫治疗与化疗的联合应用,大量基础与临床的研究结果表明,恰当的免疫化疗（chemoimmunotherapy） 能够取得较单一疗法更优的抗肿瘤效果,超越了以往认为化疗对免疫系统具有抑制作用、免疫治疗与化疗难以一起应用的传统观念。免疫化疗具有协同抗肿瘤效果的机制是多方面的,化疗可通过增强肿瘤细胞免疫原性、去除免疫抑制以及调节免疫应答反应等方式增强免疫治疗效果;另外,免疫治疗能够逆转肿瘤细胞的化疗耐药性,从而提高肿瘤细胞对化疗药物的敏感性并降低化疗的毒性作用等。目前,肿瘤免疫治疗与化疗协同作用的机制尚未完全清楚,相信通过其相关机制的不断阐明,将进一步提高免疫化疗的抗肿瘤效果并推动其临床应用。     

化疗药物的免疫调节作用研究进展

化疗药物是治疗中晚期肿瘤的有效方法.近年的研究表明,化疗药物还具有免疫调节作用.部分化疗药物可以通过诱导肿瘤细胞免疫原性细胞死亡或者进行"免疫原性调节"增强抗肿瘤免疫.化疗药物还可以影响免疫细胞和肠道菌群.同时,多项化疗联合免疫检查点抑制剂(ICIs)的临床试验正在开展.本文深入探讨化疗药物的免疫调节作用以及化疗与IC...     

靶向免疫检查点的肿瘤免疫治疗现状与趋势

针对免疫检查点的阻断是众多激活抗肿瘤免疫的有效策略之一。免疫检查点是指免疫系统中存在的一些抑制性信号通路,通过调节外周组织中免疫反应的持续性和强度避免组织损伤,并参与维持对于自身抗原的耐受。利用免疫检查点的抑制性信号通路抑制T细胞活性是肿瘤逃避免疫杀伤的重要机制。细胞毒性T淋巴细胞相关抗原-4（cytotoxic T lymphocyte-associated antigen-4,CTLA-4）抗体Ipilimumab是首个被美国FDA批准靶向免疫检查点的治疗药物,对其他的免疫检查点如程序性死亡蛋白-1（programmed death protein-1,PD-1）及其配体的抑制能够有效治疗多种肿瘤,而且能诱发持续的肿瘤缓解。靶向免疫检查点在抗肿瘤免疫治疗中有着广阔的应用前景,由于经典的化疗药物具有免疫调节作用,使得免疫治疗与化疗的联合成为新的趋势。      

白蛋白结合型紫杉醇在局部晚期/晚期头颈部肿瘤治疗中的研究进展及展望

化疗在局部晚期/晚期头颈部肿瘤的治疗中发挥重要作用,对提高肿瘤局部控制率、延缓肿瘤进展、减少远处转移及延长患者生存时间有重要的意义。TP（紫杉醇类加铂类）和TPF（紫杉醇类、顺铂及5-氟尿嘧啶）方案是头颈部肿瘤的经典有效化疗方案,故紫杉醇类（如紫杉醇和多西他赛）是头颈部肿瘤常用的化疗药物。白蛋白结合型紫杉醇作为一种新型紫杉醇类药物,以其独特剂型优势,已在多个临床试验中显示出良好的疗效及安全性。本文总结了以白蛋白结合型紫杉醇为基础分别联合其他不同化疗药物方案治疗局部晚期/晚期头颈部肿瘤的安全性及有效性,对白蛋白结合型紫杉醇在局部晚期/晚期头颈部肿瘤中应用的最新临床研究作一综述,并对未来该药治疗局部晚期/晚期头颈部肿瘤进行展望。      

叶绿酸防治肿瘤的作用及其机制研究进展

目的:总结国内外关于叶绿酸(CHL)在肿瘤防治研究中的作用及其相关机制的进展.方法:应用PubMed及CNKI期刊全文数据库检索系统,以"CHL、肿瘤"等为关键词,检索2000-2010年的相关文献497篇.纳入标准:1)CHL的理化特点;2)CHL防治肿瘤的作用;3)CHL防治肿瘤的作用机制.根据纳入标准,符合分析的文献30篇.结果:CHL具有很强的抗诱变性和较好的抗肿瘤作用.其机制涉及抗氧化和清除自由基活性;抑制致癌物DNA加合物的形成;免疫调节的潜能等.结论:CHL在肿瘤防治中显示了良好的应用前景,值得进一步深入研究.     

肿瘤免疫逃逸的研究进展

目的:探讨肿瘤免疫治疗的方法,指导理论研究和临床应用。方法:应用NCBI的PubMed文献数据库,以主要组织相容性复合物Ⅰ类分子、调节性T细胞和半乳糖凝集素等为关键词,检索2005-01-2009-10文献1080篇。纳入标准:1)抗原呈递机制的改造。2)免疫抑制因子。3)免疫调节细胞。4)负向调节途径。5)Fas/FasL的反击。最后纳入分析30篇文献,并加入早期原始文献1篇。结果:肿瘤细胞可通过多种途径逃避机体免疫系统的监视,包括肿瘤诱导的抗原呈递的减弱,免疫抑制因子的上调,增加或补充调节细胞的数量参与到免疫抑制网络,这些细胞包括调节性T细胞,骨髓的抑制性细胞,特殊的成熟和不成熟的调节性树突状细胞的亚群,另外,负向共刺激信号的激活和Fas系统的反击策略也是肿瘤逃避免疫杀伤的基本手段。结论:肿瘤免疫逃避机制的多样性,决定了抗肿瘤免疫治疗的复杂性,采取有效的抗肿瘤策略,对于临床免疫治疗将有着积极的作用。     

β-tubulin与紫杉醇类耐药在肺癌中的研究进展

目的:总结国内外关于β-tubulin与紫杉醇类耐药在肺癌治疗中的基础与临床研究进展。方法:应用Medline及CNKI期刊全文数据库系统,以"肺癌"、"微管蛋白(tubulin)"、"紫杉醇"、"化疗"为关键词,检索2010-2011年前相关文献。共检索到英文文献371篇,中文文献82篇。纳入标准:1)微管蛋白分子研究;2)肺癌细胞系与tubulin及紫杉醇类化疗耐药研究;3)与tubulin及紫杉醇类化疗耐药相关肺癌临床试验研究。结果:基础与临床研究均揭示β-tubulinⅢ与紫杉醇类耐药存在明确的负相关性,其可通过突变、过表达、多药耐药等机制诱发紫杉醇类化疗耐药,β-tu-bulinⅢ高表达预示肺癌患者预后不佳。结论:β-tubulinⅢ与肺癌含紫杉醇类化疗方案耐药相关,对其抑制或逆转为肺癌提高化疗效果提供了重要新思路。     

多西紫杉醇药物浓度-时间曲线下面积给药方式在乳腺癌患者中的应用

多西紫杉醇是一种半合成的紫杉烷类抗肿瘤药物。其通过抗微管作用抑制细胞分裂增殖,达到抑制肿瘤的目的,因此,在各期乳腺癌中均有较广泛的应用。由于其血液学不良反应大,临床上个体间用药剂量差异明显,甚至出现不规范用药现象。为了使用更高的药物剂量去获得患者的最大耐受,使患者得到以最佳治疗效果和最小不良反应为目的的精准治疗,笔者对多西紫杉醇的药代动力学及其与化疗不良反应的关系,以及依据体表面积和依据药物浓度-时间曲线下面积给药方式的相关研究进展作一综述,以期为临床上合理调节用药量提供参考。     

Effects of paclitaxel and docetaxel on EGFR-expressing human carcinoma cells under normoxic versus hypoxic conditions in vitro

Human malignant tumors, such as non-small lung, breast, ovarian, head and neck, prostate, stomach and colorectal cancers express a number of growth factor receptors (e.g. EGFR or EGFR family members) that are regulated by tumor hypoxia and contribute to tumor growth and failure of cytotoxic therapy. Paclitaxel and docetaxel are indispensable substances in the treatment of these tumors. Despite the active clinical use of taxanes, little is known about their cytotoxic activity under hypoxia. The aim of the present work was to compare the cytotoxic effect of taxanes, paclitaxel and docetaxel on the EGFR-expressing carcinoma cell lines A431, MDA-MB-231 and NCI-H358 under normoxic and hypoxic conditions. The two taxanes caused different cell cycle distribution and varying aneuploid cell formation under hypoxia. EGFR-overexpressing carcinoma cells showed hypoxia to severely affect the cytotoxicity of paclitaxel, whereas docetaxel preserved its tumor cell-killing activity even at lowest concentrations (0.5 nM), as was observed for both taxanes under normoxia.     

Effects of Paclitaxel and Docetaxel on EGFR-Expressing Human Carcinoma Cells Under Normoxic Versus Hypoxic Conditions In Vitro

Abstract

Human malignant tumors, such as non-small lung, breast, ovarian, head and neck, prostate, stomach and colorectal cancers express a number of growth factor receptors (e.g. EGFR or EGFR family members) that are regulated by tumor hypoxia and contribute to tumor growth and failure of cytotoxic therapy. Paclitaxel and docetaxel are indispensable substances in the treatment of these tumors. Despite the active clinical use of taxanes, little is known about their cytotoxic activity under hypoxia. The aim of the present work was to compare the cytotoxic effect of taxanes, paclitaxel and docetaxel on the EGFR-expressing carcinoma cell lines A431, MDA-MB-231 and NCI-H358 under normoxic and hypoxic conditions. The two taxanes caused different cell cycle distribution and varying aneuploid cell formation under hypoxia. EGFR-overexpressing carcinoma cells showed hypoxia to severely affect the cytotoxicity of paclitaxel, whereas docetaxel preserved its tumor cellkilling activity even at lowest concentrations (0.5 nM), as was observed for both taxanes under normoxia.     

Comparison of antiangiogenic activities using paclitaxel (taxol) and docetaxel (taxotere)

Tumor growth requires a competent vascular supply and angiogenesis has been considered as a potential target for the treatment of several cancers. The two clinically approved taxanes, paclitaxel and docetaxel, are novel antimitotic agents that are under extensive investigation in clinical trials. Both taxanes have demonstrated significant activity against many solid tumors, but little is known about the effect of paclitaxel and docetaxel on endothelial cell function and angiogenic processes. The purpose of our study was to examine and compare the effects of these drugs on angiogenic processes in vitro and in vivo. These processes include: proliferation, migration and differentiation of cultured human umbilical vein endothelial cells (HUVEC) (in vitro), capillary sprouting of rat aortic ring explants (ex vivo) and HT1080 tumor growth in vivo. Our results demonstrate that endothelial cells are 10-100-fold more sensitive to these drugs than tumor cells. Additionally, comparison of the taxanes demonstrated that angiogenesis is blocked by both drugs primarily via inhibition of proliferation and differentiation (tube assay) and induction of cell death. Docetaxel, however, appears to be more potent at inhibiting angiogenesis, with an IC(50) concentration 10x less than that of paclitaxel. We conclude that these important findings should be taken in account in clinical trials where tumor angiogenesis is being targeted.     

Advances in the use of taxanes in the adjuvant therapy of breast cancer

Among the novel chemotherapeutic drugs introduced in the 1990s, the taxanes have emerged as the most powerful compounds in breast cancer. Paclitaxel and docetaxel have been evaluated in the metastatic setting before proceeding with adjuvant trials. The adjuvant strategies of development of both taxanes have been different, mostly as a result of pharmacokinetic differences and dose-schedule issues. As a consequence, paclitaxel was studied nearly exclusively in sequential programs such as AC (doxorubicin/cyclophosphamide) followed by paclitaxel or doxorubicin, followed by paclitaxel, followed by cyclophosphamide. In contrast, docetaxel has been investigated in sequence (AC followed by docetaxel) and in combination chemotherapy (doxorubicin/docetaxel and docetaxel/doxorubicin/cyclophosphamide). Available results of large-scale phase III trials confirm that the taxanes have the potential to change the natural history of early-stage breast cancer. It is becoming clear that sequential chemotherapy and polychemotherapy approaches with taxanes are to be considered in the treatment of patients with node-positive breast cancer. Further results are eagerly awaited to fully understand the role of taxanes and to optimize their impact on early-stage breast cancer. It is our opinion that the real pending issue is no longer whether taxanes will make a difference in the adjuvant setting (the answer is most likely yes), but the definition of their optimal strategic use for maximum patient benefit.     

DJ-927, a novel oral taxane,overcomes P-glycoprotein-mediated multidrug resistance in vitro and in vivo

DJ-927 is a novel taxane, which was selected for high solubility, non-neurotoxicity, oral bioavailability, and potent antitumor activity. In this study, we compared the in vitro and in vivo efficacy of DJ-927 with those of paclitaxel and docetaxel. DJ-927 exhibited stronger cytotoxicity than paclitaxel and docetaxel in various tumor cell lines, especially against P-glycoprotein (P-gp)-expressing cells. The cytotoxicity of DJ-927, unlike those of other taxanes, was not affected by the P-gp expression level in tumor cells, or by the co-presence of a P-gp modulator. When intracellular accumulation of the three compounds was compared, intracellular amounts of DJ-927 were much higher than those of paclitaxel or docetaxel, particularly in P-gp-positive cells. In vivo , DJ-927 showed potent antitumor effects against two human solid tumors in male BALB/c- nu/nu mice, and yielded significant life-prolongation in a murine liver metastasis model with male C57BL/6 mice, in which neither paclitaxel nor docetaxel was effective. The results demonstrate the superior efficacy of orally administered DJ-927 over intravenously administered paclitaxel or docetaxel against P-gp-expressing tumors, probably due to higher intracellular accumulation. A phase I clinical trials of DJ-927 is currently ongoing in the US. (Cancer Sci 2003; 94: 459–466)     

Morphological and morphometric analysis of paclitaxel and docetaxel-induced peripheral neuropathy in rats

The experimentally induced neurotoxic effects of paclitaxel and docetaxel have never been compared, since no animal models of docetaxel peripheral neurotoxicity have yet been reported. In this experiment, we examined the effect of the chronic administration of these two taxanes in the Wistar rat using neurophysiological, neuropathological and morphometrical methods. Our results showed that both paclitaxel and docetaxel induced a significant, equally severe and dose-dependent reduction in nerve conduction velocity. On the contrary, the morphometric examination demonstrated that the effect on the nerve fibres was more severe after paclitaxel administration when the same schedule was used. However, the overall severity of the pathological changes was milder than expected on the basis of the neurophysiological results. Our results support the hypothesis that taxanes (and particularly docetaxel) may exert their neurotoxic effect not only on the microtubular system of the peripheral nerves, but also on other less obvious targets.     

Concurrent radiation therapy and paclitaxel or docetaxel chemotherapy in high-risk breast cancer

PURPOSE: Evidence supports the inclusion of the taxanes in the treatment of breast cancer. A recent randomized trial has shown a survival advantage to the addition of paclitaxel in the adjuvant treatment of node-positive patients. Several studies have suggested diminished local control if adjuvant radiation is delayed, while in vitro and in vivo studies have demonstrated a benefit of concurrent administration of taxanes with radiation. For these reasons, we began in 1995 to administer radiation therapy concurrently with the taxanes in advanced breast cancer. This retrospective review examines the feasibility of such treatment. METHODS AND MATERIALS: Forty-four patients were treated with concurrent radiation and either paclitaxel (29 patients) or docetaxel (15 patients). One patient received both paclitaxel and docetaxel. Eighteen patients were treated for recurrent disease, 9 had received prior radiation. Toxicity was assessed by the RTOG scale for acute and late effects. RESULTS: Concurrent radiation and taxane chemotherapy was well tolerated. Nine patients (20%) experienced Grade 3 acute skin toxicity. This was more likely with docetaxel than paclitaxel (p = 0. 04). Among patients undergoing breast conservation, there were no Grade 3 toxicities. With a median follow-up of 11 months, 1 patient has developed breast fibrosis. CONCLUSION: Concurrent administration of both paclitaxel and docetaxel with radiation resulted in acceptable toxicity. Overall, the acute skin toxicity seen with docetaxel was more pronounced. However, among patients undergoing breast conservation the taxanes were both well tolerated. Further study is necessary to assess the impact of concurrent treatment on long-term outcome.     

Taxanes for breast cancer: an evidence-based review of randomized phase II and phase III trials

The taxanes paclitaxel and docetaxel have an important role in the treatment of breast cancer, and numerous randomized trials have evaluated their efficacy for this indication. A systematic, evidence-based review was performed, which included all randomized, controlled trials evaluating taxanes for the treatment of early-or advanced-stage breast cancer that were identified in CANCERLIT and MEDLINE searches. The primary objectives of this review were to determine the dose and schedule for each taxane that was associated with the most favorable therapeutic index, and to determine whether (and under what circumstances) the taxanes improved survival. The search revealed 18 randomized phase II (n = 1) or phase III (n = 17) trials. For metastatic breast cancer, the dose and schedule associated with the most favorable therapeutic index for paclitaxel was 175 mg/m2 given as a 3-hour infusion every 3 weeks, and docetaxel was 60-100 mg/m2 given as a 1-hour infusion every 3 weeks. Survival was improved under the following circumstances: (1) when 4 cycles of paclitaxel (175 mg/m2 every 3 weeks) was given following 4 cycles of conventional doxorubicin-cyclophosphamide for axillary node-positive operable breast cancer, (2) when trastuzumab was added to paclitaxel as first-line therapy for metastatic breast cancer that overexpressed HER2/neu, and (3) when docetaxel was given as second-line therapy for anthracycline-resistant disease. Although a survival benefit was found for taxanes as a component of first-line therapy in two of six trials, the interpretation of both positive trials was confounded by a lack of crossover to taxane therapy in those who were initially randomized to receive standard therapy. The taxanes improve survival in patients with early-stage breast cancer and selected patients with metastatic breast cancer. Further research is necessary in order to identify the efficacy of docetaxel relative to paclitaxel, the optimal dose of docetaxel, the role of weekly taxane therapy, the role of trastuzumab plus taxanes in early-stage disease, and whether taxanes are more effective when given concomitantly or sequentially in patients with early-stage disease.     

Rationale and use of epirubicin-based therapy in the adjuvant setting

The taxanes paclitaxel and docetaxel have an important role in the treatment of breast cancer, and numerous randomized trials have evaluated their efficacy for this indication. A systematic, evidence-based review was performed, which included all randomized, controlled trials evaluating taxanes for the treatment of early- or advanced-stage breast cancer that were identified in CANCERLIT and MEDLINE searches. The primary objectives of this review were to determine the dose and schedule for each taxane that was associated with the most favorable therapeutic index, and to determine whether (and under what circumstances) the taxanes improved survival. The search revealed 18 randomized phase II (n=1) or phase III (n=17) trials. For metastatic breast cancer, the dose and schedule associated with the most favorable therapeutic index for paclitaxel was 175 mg/m2 given as a 3-hour infusion every 3 weeks, and docetaxel was 60-100 mg/m2 given as a 1-hour infusion every 3 weeks. Survival was improved under the following circumstances: (1) when 4 cycles of paclitaxel (175 mg/m2 every 3 weeks) was given following 4 cycles of conventional doxorubicin- cyclophosphamide for axillary node-positive operable breast cancer, (2) when trastuzumab was added to paclitaxel as first-line therapy for metastatic breast cancer that overexpressed HER2/neu, and (3) when docetaxel was given as second-line therapy for anthracycline-resistant disease. Although a survival benefit was found for taxanes as a component of first-line therapy in two of six trials, the interpretation of both positive trials was confounded by a lack of crossover to taxane therapy in those who were initially randomized to receive standard therapy. The taxanes improve survival in patients with early-stage breast cancer and selected patients with metastatic breast cancer. Further research is necessary in order to identify the efficacy of docetaxel relative to paclitaxel, the optimal dose of docetaxel, the role of weekly taxane therapy, the role of trastuzumab plus taxanes in early-stage disease, and whether taxanes are more effective when given concomitantly or sequentially in patients with early-stage disease     

Taxanes synergize with the bispecific antibody MDXH447 to enhance antibody-dependent cell-mediated cytotoxicity

The interaction between antibody based therapy and cytotoxic chemotherapy is complex. To explore these interactions we investigated, in vitro, the effects of IC20 growth inhibitory concentrations of taxanes on bispecific antibody-mediated tumor cell cytotoxicity. MDXH447 is a bispecific antibody with specificity for the high affinity IgG receptor (CD64) and the type I epidermal growth factor receptor type (EGF-R). A431 cells, an epidermoid carcinoma cell line that over expresses EGF-R, were exposed to a range of IC20 growth inhibitory concentrations of paclitaxel or docetaxel. Interferon gamma activated monocytes were armed with MDXH447 and a standard chromium release antibody-dependent cell-mediated cytotoxicity (ADCC) assay was performed. Using the Chou and Talalay median effect analysis, we found that MDXH447-mediated ADCC was enhanced when A431 target cells were pretreated with paclitaxel or docetaxel. Median effect analysis of these interactions supported a synergistic interaction (CI < 1). Pretreatment of A431 cells with taxanes did not increase EGF-R expression compared to untreated controls. A431 epidermoid carcinoma cells pretreated with IC20 growth inhibitory concentrations of taxanes enhanced interferon gamma activated monocyte mediated ADCC killing through MDXH447.