表皮生长因子受体酪氨酸激酶抑制剂ZD1839的研究进展

在过去的几十年中 ,人们一直怀着极大的兴趣研发新药来提高实体瘤的治疗效果。然而 ,传统的细胞毒药物选择性低 ,毒副作用大 ,容易产生耐药性。近 10多年来 ,随着分子肿瘤学的发展以及对肿瘤与宿主之间复杂关系的深入研究 ,发现了某些与肿瘤发生、发展、浸润及转移有关的重要环     

表皮生长因子受体酪氨酸激酶抑制剂ZD1839对宫颈癌细胞的作用

目的探讨选择性表皮生长因子受体酪氨酸激酶抑制剂ZD1839对宫颈癌细胞的作用。方法以宫颈鳞癌Siha细胞,腺癌Hela细胞为研究对象,利用MTT法检测ZD1839单药使用以及与顺铂联用分别对Siha和Hela细胞的增殖抑制作用。采用Burgi法分析联合用药的效果,并用流式细胞仪检测Siha和Hela细胞的细胞周期分布及凋亡率改变。结果单独使用ZD1839能够抑制Siha、Hela细胞的增殖,其IC50值分别是1.48μmol/L、2.67μmol/L,而且抑制作用呈剂量依赖性。ZD1839能增强顺铂对Siha、Hela细胞的抑制作用,Burgi修正公式所得Q值分别为1.06±0.03(Siha)、1.13±0.01(Hela)。ZD1839使G0/G1期细胞增加,S期细胞减少,细胞凋亡率增加。结论ZD1839能够抑制宫颈癌细胞的增殖,并且能够增强顺铂对宫颈癌细胞的抑制作用,该抑制作用可能与其使肿瘤细胞停滞于G1期和诱导肿瘤细胞的凋亡有关。     

表皮生长因子受体酪氨酸激酶抑制剂ZD1839对鼻咽癌细胞系的作用

ZDl839是一种喹唑啉类化合物,它是一种口服的选择性的表皮生长因子受体酪氨酸激酶抑制剂,已被美国食品药品管理局批准用于治疗晚期非小细胞肺癌。鼻咽癌是一种存在表皮生长因子受体表达的上皮源性的恶性肿瘤,ZDl839对其作用如何还未见有报道。本实验通过体外研究初步探讨ZDl839在鼻咽癌治疗中的可能价值。     

表皮生长因子受体酪氨酸激酶抑制剂ZD1839与奥沙利铂联合对人肺癌A549细胞的作用

背景与目的:ZD1839是一种表皮生长因子受体酪氨酸激酶的小分子抑制剂,是目前肺癌分子靶向治疗中较为成熟的药物,因其单药临床有效率低,如何与化疗联合提高抗癌效应受到关注.本实验通过研究ZD1839联合奥沙利铂的不同给药方案对人肺腺癌细胞A549的杀伤作用,探讨两药联合的最佳模式.方法:以药物联合效应测定方法,评价ZD1839和奥沙利铂不同给药顺序对A549细胞的抑制作用,以流式细胞仪测定不同联合方案对A549细胞周期分布及凋亡率的影响.观察ZD1839、奥沙利铂不同给药方案作用时,裸鼠A549细胞移植瘤生长情况,测定肿瘤生长抑制率.结果:先奥沙利铂后ZD1839的序贯给药方案表现出明显的协同作用,药物联合指数为0.51±0.01;而先ZD1839后给予奥沙利铂时,药物联合指数为1.56±0.03,两药间为拮抗作用.先奥沙利铂后ZD1839组G2/M期细胞比例与其他组相比明显增加,达到37.9%(P＜0.05),细胞凋亡率达到22.3%.体内实验表明,先奥沙利铂后ZD1839组抑瘤率最高,达到58.9%;而先奥沙利铂 ZD1839 24 h后ZD1839 48 h组的抑瘤率为52.4%,ZD1839后奥沙利铂组的抑瘤率为30.6%.结论:先奥沙利铂后ZD1839序贯给药对A549细胞增殖的抑制作用更强.     

表皮生长因子受体酪氨酸激酶抑制剂联合化疗治疗肺癌的研究进展

表皮生长因子受体(EGFR)酪氨酸激酶抑制剂(EGFR-TKI)对EGFR突变肺癌患者表现出很好的疗效,对于EGFR野生型肺癌患者化疗药物是首选,EGFR-TKI和化疗药物联合在基础研究方面表现出良好的协同作用,而在临床研究方面与其两药联合的时序有关.     

表皮生长因子受体与酪氨酸激酶抑制剂在NSCLC靶向治疗中的研究

近年来，随着分子生物学和人类基因组学的发展，人们对肺癌的发生发展、侵袭、转移的分子机制，以及一些生物信息传导通路的认识得到进一步加深，与肺癌相关的表皮生长因子受体（epidermal growth factor receptor，EGFR）作为治疗靶点也日益受到人们关注。EGFR的激活会引起自身磷酸化及其它许多胞内物质的磷酸化从而促进细胞的有丝分裂与分化能力，     

伊立替康联合顺铂与拓扑替康联合顺铂二线治疗小细胞肺癌的比较研究

目的：回顾性观察伊立替康联合顺铂（IP组）与拓扑替康联合顺铂（TP组）二线治疗难治型小细胞肺癌的近期、远期疗效及毒副作用。方法：共62例患者，均为一线EP方案治疗失败且在3～6个月内出现进展，IP组：伊立替康60mg／m^2，第1、8天，DDP25mg／m^2，第1～3天，静脉滴注；TP组：拓扑替康0．75mg／m^2，第1—5天，DDP25mg／m^2，第1～3天，静脉滴注。均21天为1周期。每2个周期评价疗效。结果：IP组30例，有效率33，3％（10／30），TP组32例，有效率37．5％（12／32），两组近期疗效无差异（P〉0．05）。两组中位疾病进展时间（mTFP）均为3．0个月；中位生存期（MST）分别为12个月和11．5个月，无显著性差异（P〉0．05）。两组毒副作用主要表现为：Ⅲ-Ⅳ度粒细胞下降TP组高于IP组（31．3％vs．23．3％），但两组无显著性差异（P〉0．05）；Ⅲ-Ⅳ度血小板下降TP组高于IP组（18．8％vs．6．6％），两组有显著性差异（P〈0．05）；延迟性腹泻IP组高于TP组（30．0％vs．3．1％）。结论：伊立替康联合顺铂与拓扑替康联合顺铂二线治疗难治型小细胞肺癌均取得较好疗效，两方案毒副作用均可以耐受。     

表皮生长因子受体酪氨酸激酶抑制剂Gefitinib对鼻咽癌荷瘤裸鼠移植瘤生长作用的实验研究

背景与目的:Gefitinib是一种喹唑啉类化合物,它是一种口服的选择性的表皮生长因子受体酪氨酸激酶抑制剂,已被美国FDA批准用于治疗晚期非小细胞肺癌.我们在体外的研究结果显示Gefitinib对鼻咽低分化鳞癌细胞株CNE2和SUNE1以及鼻咽高分化鳞癌细胞株CNE1的增殖皆有明显的抑制作用.本实验通过体内研究方法初步探讨Gefitinib对鼻咽癌荷瘤裸鼠移植瘤的生长有无抑制作用,同时探讨Gefitinib与细胞毒药物顺铂合用在体内对鼻咽癌生长的影响.方法:将处于对数生长期的CNE2细胞制成1×107/ml的细胞悬液,取0.2 ml的CNE2细胞悬液接种于裸鼠右侧腋窝皮下,7天后肿瘤体积在100～200 mm3之间,根据性别分层,按肿瘤体积大小将裸鼠随机分成溶剂对照组、Gefitinib(100 mg/kg)组、Gefitinib(200mg/kg)组、DDP组、Gefitinib(100 mg/kg)+DDP组.每组动物数8只,雌雄各半.Gefitinib灌胃给药,1周内连续5天,连用4周;DDP腹腔注射给药,每周1次,共4次.药物处理前及处理后每2天测量每只裸鼠肿瘤的长、宽最大垂直直径的大小,计算肿瘤体积.用药结束后2天,处死裸鼠,取出肿瘤组织,称重,计算抑瘤率.结果:治疗后各组裸鼠肿瘤体积的生长曲线显示溶剂对照组的生长速度在各时间点上均快于治疗组.进一步统计学分析显示治疗结束时,Gefitinib(200 mg/kg)组的肿瘤体积明显小于溶剂对照组(P=0.02);而Gefitinib(100 mg/kg)组和溶剂对照组相比,肿瘤体积的变化则无显著性差异(P=0.163),DDP组以及Gefitinib(100 mg/kg)+DDP组的肿瘤体积皆明显小于溶剂对照组(P值分别为0.007和0.001),DDP组与Gefitinib(100 mg/kg)+DDP组的肿瘤体积的比较则无显著性差异.Gefitinib(100 mg/kg)组抑瘤率26.3%,Gefitinib(200 mg/kg)组抑瘤率30.6%,DDP组抑瘤率45.7%,Gefitinib(100 mg/kg)+DDP组抑瘤率54.8%.Gefitinib(100mg/kg)组与溶剂对照组相比,治疗结束后平均瘤重无显著性差异;Gefitinib(200 mg/kg)组、DDP组、Gefitinib(100 mg/kg)+DDP组与溶剂对照组平均瘤重皆有显著性差异,DDP组与Gefitinib(100 mg/kg)+DDP组平均瘤重无显著性差异.结论:Gefitinib对CNE2鼻咽癌荷瘤裸鼠移植瘤的生长具有抑制作用,其与DDP合用未能显著增强DDP的抗CNE2鼻咽癌荷瘤裸鼠移植瘤的效果.     

伊立替康、奥沙利铂及氟尿嘧啶对人大肠癌LoVo细胞株作用的实验研究

目的：研究国产盐酸伊立替康（CPT-11）、奥沙利铂（L-OHP）及氟尿嘧啶（5-FU）对人大肠癌细胞株LoVo的生长抑制作用。方法：采用MTT法观察上述药物单药应用、两药及三药同时或序贯联合应用对大肠癌LoVo细胞生长的影响,评价药物联合应用的效果。结果：单药应用、两药联合及三药联合应用均对大肠癌LoVo细胞有显著的抑制作用（P〈0．05）;两药联合应用均优于各自单药的抑制效果,CPT-11联合L-OHP弱于CPT-11或L-OHP与5-FU联合的抑制效果（P〈0．05）,由L-OHP到CPT-11小剂量序贯联合具有明显的协同作用;三药联合应用的抑制效果显著优于两药联合（P〈0．05）,由5-FU＋L-OHP到5-FU＋CPT-11的序贯联合应用与三药同步联合应用无显著性差异（P〉0．05）,但由5-FU＋CPT-11到5-FU＋L-OHP序贯应用时明显低于三药同步应用的效果（P〈0．05）,且三药全量及半量联合应用效果差异无显著性（P〉0．05）。结论：由5-FU＋L-OHP到5-FU＋CPT-11的小剂量序贯联合应用具有高效协同抑制大肠癌细胞株LoVo的作用,可为临床难治性和复发性大肠癌患者的化疗及小剂量序贯化疗提供参考。     

ZD1839 ('Iressa'), a specific oral epidermal growth factor receptor-tyrosine kinase inhibitor, potentiates radiotherapy in a human colorectal cancer xenograft model

The effect of ZD1839 ('Iressa'), a specific inhibitor of the tyrosine kinase activity of the epidermal growth factor receptor, on the radiation response of human tumour cells (LoVo colorectal carcinoma) was evaluated in vitro and in vivo. ZD1839 (0.5 microM, incubated days 1-5) significantly increased the anti-proliferative effect of fractionated radiation treatment (2 Gy day(-1), days 1-3) on LoVo cells grown in vitro (P=0.002). ZD1839 combined with either single or fractionated radiotherapy in mice bearing LoVo tumour xenografts, also produced a highly significant increase in tumour growth inhibition (P< or = 0.001) when compared to treatment with either modality alone. The radio-potentiating effect of ZD1839 was more apparent when radiation was administered in a fractionated protocol. This phenomenon may be attributed to an anti proliferative effect of ZD1839 on tumour cell re-population between radiotherapy fractions. These data suggest radiotherapy with adjuvant ZD1839 could enhance treatment response. Clinical investigation of ZD1839 in combination with radiotherapy is therefore warranted.     

Differential radiosensitisation by ZD1839 (Iressa), a highly selective epidermal growth factor receptor tyrosine kinase inhibitor in two related bladder cancer cell lines

The epidermal growth factor receptor (EGFR) is expressed in a wide variety of epithelial tumours including carcinoma of the bladder. Stimulation of the EGFR pathway is blocked by ZD1839 (Iressa), a highly selective EGFR tyrosine kinase inhibitor. Radical radiotherapy is an established organ sparing treatment option for muscle invasive bladder cancer and this study has explored the possibility for the use of ZD1839 as a radiosensitiser in this scenario. The effect of combination treatment with ZD1839 (0.01 microM) and ionising radiation in the established bladder cancer cell lines MGH-U1 and its radiosensitive mutant clone S40b was measured by clonogenic assays. A highly significant radiosensitising effect was seen in both cell lines (P < 0.001 for MGH-U1 and S40b cell lines). This effect was independent of the concentration of the drug and the duration of exposure prior to treatment with ionising radiation. Cell cycle kinetics of both cell lines was not significantly altered with ZD1839 (0.01 microM) as a single agent. A modest induction of apoptosis was observed with ZD1839 (0.01 microM) as a single agent, but a marked induction was observed with the combination treatment of ZD1839 and ionising radiation. These results suggest a potentially important role for ZD1839 in combination with radiotherapy in the treatment of muscle invasive bladder cancer.     

The effect of gefitinib (Iressa,ZD1839) in combination with oxaliplatin is schedule-dependent in colon cancer cell lines

Background Clinical trials of gefitinib (Iressa, ZD1839) in combination with cytotoxic agents have been carried out or are ongoing in several varieties of tumor. To provide a rationale for future clinical trials, the effects of combining gefitinib with oxaliplatin in different sequences of administration and different dose ratios in two colon cancer cell lines were evaluated.Materials and methods The colon cancer cell lines HT-29 and LoVo were used. The methods consisted of median effect and combination index analysis, Western blot, mass spectrometry, and a cell death ELISA.Results In vitro analysis demonstrated that the combination effects of the two agents were sequence-dependent. Changing the sequence of administration from gefitinib first to gefitinib last changed the combination effect from antagonism to synergy. The dose ratio between the two agents affected the combination effects. When equiactive doses of the two agents were used with the sequence gefitinib following oxaliplatin, the greatest level of synergism was obtained (CI=0.6±0.2, P=0.032). Further evaluation revealed that gefitinib significantly inhibited removal of Pt-DNA adducts (P<0.05), providing a potential explanation for the sequence-dependent synergy observed with gefitinib following oxaliplatin. However, this effect was not dose-dependent. Additional studies demonstrated that gefitinib enhanced the effects of oxaliplatin by maintaining oxaliplatin-induced apoptosis, and equiactive dose of gefitinib following oxaliplatin induced prominent enhancement of apoptosis.Conclusions Oxaliplatin followed by an equiactive relative dose of gefitinib is an appropriate combination for evaluation in colon cancer.     

ZD1839, a novel,oral epidermal growth factor receptor-tyrosine kinase inhibitor,as salvage treatment in patients with advanced non-small cell lung cancer. Experience from a single center participating in a compassionate use program

Objective: We evaluated the efficacy and tolerability of the orally active, selective epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) ZD1839 in patients with pretreated advanced non-small cell lung cancer (NSCLC) participating in a compassionate use program. Patients and methods: Thirty-one patients with advanced, unresectable and progressive NSCLC, previously treated with one or two chemotherapy regimens, received ZD1839 250 mg orally once daily. Patients who had received only one prior chemotherapy regimen had to be considered unsuitable for second-line chemotherapy. Results: The disease control rate was 32% (95% CI: 15.8–48.7) (1/31 patients had a partial response and 9/31 patients had stable disease) and the median overall survival 23 weeks (range 4–40). Symptom improvement was reported by 39% of patients overall and by 83% of patients who achieved disease control. The median time to symptom improvement was 3 weeks (range 2–4). Adverse events were generally mild (grade I or II) and reversible and consisted mostly of skin rash, diarrhea and fatigue. Conclusions: ZD1839 demonstrated clinically meaningful antitumor activity with significant improvement in symptoms in this heavily pretreated group of patients with advanced NSCLC. Furthermore, ZD1839 showed a favorable toxicity profile, with the majority of adverse events being mild and reversible.     

ZD1839 (Iressa), a novel epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, potently inhibits the growth of EGFR-positive cancer cell lines with or without erbB2 overexpression.

Overexpression of the growth factor receptors EGFR and erbB2 occurs frequently in several human cancers and is associated with aggressive tumour behaviour and poor patient prognosis. We have investigated the effects of ZD1839 (Iressa), a novel EGFR tyrosine kinase inhibitor, on the growth, in vitro and in vivo, of human cancer cell lines expressing various levels of EGFR and erbB2. Proliferation of EGFR-overexpressing A431 and MDA-MB-231 cells in vitro was potently inhibited (50%-70%) by ZD1839 with half-maximally effective doses in the low nanomolar range. In parallel, ZD1839 blocked autophosphorylation of EGFR and prevented activation of PLC-gamma 1, ERK MAP kinases and PKB/Akt by EGF. It also inhibited proliferation in EGFR(+) cancer cell lines overexpressing erbB2 (SKBr3, SKOV3, BT474) by between 20% and 80%, effects which correlated with inhibition of EGF-dependent erbB2 phosphorylation and activation of ERK MAP kinase and PKB/Akt in SKOV3 cells. Oral administration of ZD1839 inhibited the growth of MDA-MB-231 and SKOV3 tumours, established as xenografts in athymic mice, by 71% and 32%, respectively. Growth inhibition coincided with reduced proliferation but no change in apoptotic index. Collectively, these results show that ZD1839, at the doses studied, is a potent inhibitor of proliferation not only in cells overexpressing EGFR but also in EGFR(+) cells that overexpress erbB2.     

Enhancement of tumor radioresponse by combined treatment with gefitinib (Iressa, ZD1839), an epidermal growth factor receptor tyrosine kinase inhibitor, is accompanied by inhibition of DNA damage repair and cell growth in oral cancer

Molecular blockade of EGFR with either an EGFR MAb or an EGFR TKI enhances the radiosensitivity of human SCCs. In the present study, we investigated whether treatment with the EGFR TKI gefitinib (Iressa, ZD1839) improves the response to radiotherapy in the OSCC cell lines HSC2 and HSC3. We examined potential mechanisms that may contribute to the enhanced radiation response induced by gefitinib. Growth inhibition was observed in vitro with radiation or gefitinib. A cooperative antiproliferative effect was obtained when cancer cells were treated with radiation followed by gefitinib. Cells treated with a combination of radiation and gefitinib arrested in G(1) and G(2)-M phases, with a decrease in the S-phase population. While radiation alone did not significantly affect MEK1/2 and p38 MAPK autophosphorylation, the combination of gefitinib and radiation completely inhibited the downstream signaling of EGFR. Results from DNA damage repair analysis in cultured OSCC cells demonstrated that gefitinib had a strong inhibitory effect on DNA-PKc pathways after radiation. Tumor xenograft studies demonstrated that the combination of gefitinib and radiation caused growth inhibition and tumor regression of well-established OSCC tumors in athymic mice; tumor volume was reduced from 1,008.2 to 231.4 mm(3) in HSC2 cells (p < 0.01) and from 284.2 to 12.4 mm(3) in HSC3 cells (p < 0.01). Immunohistochemical analysis of OSCC xenografts revealed that gefitinib caused a striking decrease in tumor cell proliferation when combined with radiotherapy. Overall, we conclude that gefitinib enhances tumor radioresponse by multiple mechanisms that may involve antiproliferative growth inhibition and effects on DNA repair after exposure to radiation.     

Two different schedules of irinotecan (CPT-11) in patients with advanced colorectal carcinoma relapsing after a 5-fluorouracil and leucovorin combination. A randomized study

Purpose To evaluate the efficacy and safety of irinotecan as second-line treatment in patients with advanced colorectal cancer (ACC) failing or relapsing after 5-fluorouracil (5-FU) plus leucovorin (LV) standard chemotherapy.Patients and methods Irinotecan was randomly administered in two different schedules (once every 3 weeks, and every 10 days) in patients failing prior 5-FU plus LV. Patients were randomized to two treatment groups: group A received irinotecan 350 mg/m² every 21 days and group B received irinotecan 175 mg/m² days 1 and 10 every 21 days.Results Group A comprised 60 patients: 34 male/26 female, median age 64 years (range 48–70 years), and median Karnofsky performance status (PS) 90. Their metastatic sites included liver (n=47), lymph nodes (n=27), lung (n=14), abdomen (n=14), pelvis (n=8), "other" (n=2), and local recurrence (n=12). Group B comprised 60 patients: 36 male/24 female, median age 62 years (46–70 years), and median PS 90. Their metastatic sites included liver (n=49), lymph nodes (n=29), lung (n=17), abdomen (n=16), pelvis (n=11), "other" (n=2), and local recurrence (n=13). Group A showed the following responses: complete response (CR) 2, partial response (PR) 12, stable disease (SD) 21, progressive disease (PD) 26, overall response rate (ORR) 23%, tumor growth control 58%. Group B showed the following responses: CR 1, PR 14, SD 22, PD 23; ORR 25%; tumor growth control 62%. Toxicities included acute cholinergic syndrome (group A 53%, group B 19%; P<0.0001), late-onset diarrhea grade 1/2 (group A 21%, group B 46%) and grade 3/4 (group A 41%, group B 66%; P<0.0001), nausea and vomiting grade 1/2 (group A 34%, group B 59%) and grade 3/4 (group A 30%, group B 12%; P<0.0001), neutropenia grade 3/4 (group A 27%, group B 28%; P<0.03), with febrile neutropenia seen in only four patients in group A, anemia grade more than 2 (group A 28%, group B 12%; P<0.05), asthenia grade more than 3 (group A 24%, group B 18%; P<0.001), and alopecia grade more than 3 (group A 40%, group B 34%; P<0.2).Conclusions The present study indicates that, in patients with ACC who have relapsed after 5-FU plus LV, the administration of irinotecan fractionated into two doses every 21 days yields a similar efficacy to, but a much lower incidence of toxicity than, the same total dose of irinotecan administered once every 21 days.     

Phase I pharmacokinetic trial of the selective oral epidermal growth factor receptor tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in Japanese patients with solid malignant tumors.

BACKGROUND: This phase I dose-escalating study investigated the tolerability and toxicity of the selective epidermal growth factor receptor tyrosine kinase inhibitor gefitinib ('Iressa', ZD1839) in Japanese patients with solid tumors. Thirty-one patients were included. PATIENTS AND METHODS: Patients initially received a single oral dose of gefitinib followed by 10-14 days of observation. Oral gefitinib was subsequently administered on 14 consecutive days, every 28 days. Dose escalation was from 50 mg/day to a maximum of 925 mg/day or dose-limiting toxicity (DLT). RESULTS: Most adverse events were mild (grade 1/2); the most frequent were an acne-like rash and gastrointestinal effects. Two of six patients at 700 mg/day had DLT; no further dose escalation occurred. C(max) was reached within 3-7 h and exposure to gefitinib increased with dose. Mean terminal half-life following multiple dosing was 50.1 h (range 27.8-79.7 h). A partial response (duration 35-361 days) was observed in five of the 23 patients with non-small-cell lung cancer over a range of doses (225-700 mg/day), and seven patients with a range of tumors had disease stabilization (duration 40-127 days). CONCLUSIONS: In conclusion, gefitinib showed a favorable tolerability profile in Japanese patients. The safety profile, pharmacokinetic parameters and antitumor activity observed in our study are comparable to those observed in patients from the USA and Europe.