吉非替尼和西妥昔单抗对携带表皮生长因子受体突变的非小细胞肺癌的不同作用。

Differential effects of gefitinib and cetuximab on non-small-cell lung cancers bearing epidermal growth factor receptor mutations.

作者信息

Mukohara Toru, Engelman Jeffrey A, Hanna Nasser H, Yeap Beow Y, Kobayashi Susumu, Lindeman Neal, Halmos Balázs, Pearlberg Joseph, Tsuchihashi Zenta, Cantley Lewis C, Tenen Daniel G, Johnson Bruce E, Jänne Pasi A

机构信息

Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.

出版信息

J Natl Cancer Inst. 2005 Aug 17;97(16):1185-94. doi: 10.1093/jnci/dji238.

DOI:10.1093/jnci/dji238

PMID:16106023

Abstract

BACKGROUND

Many patients with non-small-cell lung cancer (NSCLC) who achieve radiographic responses to treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors gefitinib and erlotinib have somatic mutations in the EGFR tyrosine kinase domain. However, little is known about the efficacy of cetuximab, an antibody against the EGFR extracellular domain, in EGFR mutant NSCLC.

METHODS

NSCLC cell lines carrying wild-type EGFR (A549, H441, and H1666) or mutant EGFR (H3255, DFCILU-011, PC-9, and HCC827) were treated with various dilutions of gefitinib or cetuximab relative to maximal achievable serum concentration. Cell growth was analyzed by the MTS assay, with differences between dose-response curves analyzed nonparametrically. Apoptosis was analyzed by propidium iodide staining and immunoblotting for PARP. Phosphorylation of EGFR and the downstream signaling components ERK1/2 and Akt were analyzed by immunoblotting. Statistical tests were two-sided.

RESULTS

Growth of NSCLC lines with wild-type EGFR was slightly (A549 and H441) or moderately (H1666) inhibited by gefitinib and cetuximab, and the effects of the two agents were similar. Both agents also induced no (H441) or moderate (H1666) apoptosis in NSCLC cells with wild-type EGFR. By contrast, gefitinib was statistically significantly more effective than cetuximab at inhibiting growth of EGFR mutant cells (H3255: P = .003, DFCILU-011: P = .011, and PC-9: P = .003), and gefitinib-treated EGFR mutant cells had higher levels of apoptosis than cetuximab-treated cells (mean fold increase in apoptosis by 1 microM of gefitinib and 10 microg/mL of cetuximab relative to control, H3255: 8.3 [95% confidence interval {CI} = 4.8 to 11.8] and 2.1 [95% CI = 2.0 to 2.2], respectively, P = .025; DFCILU-011: 5.7 [95% CI = 5.1 to 6.3] and. 0.9 [95% CI = 0.3 to 1.5], respectively, P < .001). Gefitinib treatment decreased EGFR, ERK1/2, and Akt phosphorylation in EGFR mutant cell lines whereas cetuximab had relatively little effect. Both gefitinib and cetuximab inhibited the growth of HCC827 cells, but gefitinib inhibited growth to a greater extent (P = .003).

CONCLUSIONS

EGFR mutations in NSCLC cells are associated with sensitivity to gefitinib but not to cetuximab.

摘要

背景

许多非小细胞肺癌（NSCLC）患者在接受表皮生长因子受体（EGFR）酪氨酸激酶抑制剂吉非替尼和厄洛替尼治疗后出现影像学反应，其EGFR酪氨酸激酶结构域存在体细胞突变。然而，对于抗EGFR细胞外结构域抗体西妥昔单抗在EGFR突变型NSCLC中的疗效知之甚少。

方法

用相对于最大可达到血清浓度的不同稀释度的吉非替尼或西妥昔单抗处理携带野生型EGFR（A549、H441和H1666）或突变型EGFR（H3255、DFCILU - 011、PC - 9和HCC827）的NSCLC细胞系。通过MTS试验分析细胞生长情况，用非参数方法分析剂量反应曲线之间的差异。通过碘化丙啶染色和PARP免疫印迹分析细胞凋亡情况。通过免疫印迹分析EGFR以及下游信号成分ERK1/2和Akt的磷酸化情况。统计检验为双侧检验。

结果

野生型EGFR的NSCLC细胞系的生长受到吉非替尼和西妥昔单抗的轻度（A549和H441）或中度（H1666）抑制，两种药物的作用相似。两种药物在野生型EGFR的NSCLC细胞中均未诱导（H441）或中度（H1666）凋亡。相比之下，吉非替尼在抑制EGFR突变细胞生长方面在统计学上显著比西妥昔单抗更有效（H3255：P = 0.003，DFCILU - 011：P = 0.011，PC - 9：P = 0.003），并且吉非替尼处理的EGFR突变细胞比西妥昔单抗处理的细胞具有更高的凋亡水平（相对于对照，1μM吉非替尼和10μg/mL西妥昔单抗诱导凋亡的平均倍数增加，H3255分别为8.3 [95%置信区间{CI}=4.8至11.8]和2.1 [95% CI = 2.0至2.2]，P = 0.025；DFCILU - 011分别为5.7 [95% CI = 5.1至6.3]和0.9 [95% CI = 0.3至1.5]，P < 0.001）。吉非替尼处理降低了EGFR突变细胞系中EGFR、ERK1/2和Akt的磷酸化，而西妥昔单抗的作用相对较小。吉非替尼和西妥昔单抗均抑制HCC827细胞的生长，但吉非替尼抑制作用更强（P = 0.003）。