Hopfner Michael, Sutter Andreas P, Huether Alexander, Baradari Viola, Scherubl Hans
Klinik fur Gastroenterologie und Gastrointestinale Onkologie, Vivantes-Klinikum Am Urban, Dieffenbachstr. 1, Berlin 10967, Germany.
World J Gastroenterol. 2006 Sep 21;12(35):5635-43. doi: 10.3748/wjg.v12.i35.5635.
To investigate the antineoplastic potency of the novel insulin-like growth factor 1 receptor (IGF-1R) tyrosine kinase inhibitor (TKI) NVP-AEW541 in cell lines and primary cell cultures of human colorectal cancer (CRC).
Cells of primary colorectal carcinomas were from 8 patients. Immunostaining and crystal violet staining were used for analysis of growth factor receptor protein expression and detection of cell number changes, respectively. Cytotoxicity was determined by measuring the release of the cytoplasmic enzyme lactate dehydrogenase (LDH). The proportion of apoptotic cells was determined by quantifying the percentage of sub-G1 (hypodiploid) cells. Cell cycle status reflected by the DNA content of the nuclei was detected by flow cytometry.
NVP-AEW541 dose-dependently inhibited the proliferation of colorectal carcinoma cell lines and primary cell cultures by inducing apoptosis and cell cycle arrest. Apoptosis was characterized by caspase-3 activation and nuclear degradation. Cell cycle was arrested at the G1/S checkpoint. The NVP-AEW541-mediated cell cycle-related signaling involved the inactivation of Akt and extracellular signal-regulated kinase (ERK) 1/2, the upregulation of the cyclin-dependent kinase inhibitors p21(Waf1/CIP1) and p27(Kip1), and the downregulation of the cell cycle promoter cyclin D1. Moreover, BAX was upregulated during NVP-AEW541-induced apoptosis, whereas Bcl-2 was downregulated. Measurement of LDH release showed that the antineoplastic effect of NVP-AEW541 was not due to general cytotoxicity of the compound. However, augmented antineoplastic effects were observed in combination treatments of NVP-AEW541 with either 5-FU, or the EGFR-antibody cetuximab, or the HMG-CoA-reductase inhibitor fluvastatin.
IGF-1R-TK inhibition is a promising novel approach for either mono- or combination treatment strategies of colorectal carcinoma and even for CRC chemoprevention.
研究新型胰岛素样生长因子1受体（IGF-1R）酪氨酸激酶抑制剂（TKI）NVP-AEW541对人结直肠癌（CRC）细胞系和原代细胞培养物的抗肿瘤效力。
原发性结直肠癌细胞来自8例患者。免疫染色和结晶紫染色分别用于分析生长因子受体蛋白表达和检测细胞数量变化。通过测量细胞质酶乳酸脱氢酶（LDH）的释放来确定细胞毒性。通过定量亚G1期（亚二倍体）细胞的百分比来确定凋亡细胞的比例。通过流式细胞术检测细胞核DNA含量反映的细胞周期状态。
NVP-AEW541通过诱导凋亡和细胞周期阻滞剂量依赖性地抑制结直肠癌细胞系和原代细胞培养物的增殖。凋亡的特征是半胱天冬酶-3激活和核降解。细胞周期阻滞在G1/S检查点。NVP-AEW541介导的细胞周期相关信号传导涉及Akt和细胞外信号调节激酶（ERK）1/2的失活、细胞周期蛋白依赖性激酶抑制剂p21（Waf1/CIP1）和p27（Kip1）的上调以及细胞周期促进因子细胞周期蛋白D1的下调。此外，在NVP-AEW541诱导的凋亡过程中BAX上调，而Bcl-2下调。LDH释放的测量表明NVP-AEW541的抗肿瘤作用不是由于该化合物的一般细胞毒性。然而，在NVP-AEW541与5-氟尿嘧啶、或表皮生长因子受体（EGFR）抗体西妥昔单抗、或HMG-CoA还原酶抑制剂氟伐他汀的联合治疗中观察到增强的抗肿瘤作用。
IGF-1R-TK抑制是一种有前景的新型方法，可用于结直肠癌的单药或联合治疗策略，甚至用于结直肠癌的化学预防。
