Ogawa Kazuhiko, Utsunomiya Tohru, Mimori Koshi, Tanaka Fumiaki, Haraguchi Naotsugu, Inoue Hiroshi, Murayama Sadayuki, Mori Masaki
Department of Molecular and Surgical Oncology, Medical Institute of Bioregulation, Kyushu University, Beppu, Japan.
Int J Oncol. 2006 Mar;28(3):705-13.
Identification of the genes that are differentially-expressed between radiosensitive and radioresistant cancer cells is important to the ability to predict the clinical effectiveness of radiotherapy. We established radioresistant human pancreatic cancer cell lines using fractionated irradiation in order to identify genes that are differentially-expressed between parental lines and radioresistant cell sublines. Six pancreatic cancer cell lines (PK-1, PK-8, PK-9, T3M4, MiaPaCa2 and PANC-1) were treated with 10 Gy fractionated irradiation at approximately two-week intervals (total dose 150-180 Gy). Five radioresistant sublines (PK-1, PK-8, PK-9, T3M4, and MiaPaCa2) were successfully established. Using oligonucleotide microarrays containing 17,086 genes, we identified 73 up-regulated genes and 55 down-regulated genes common to radioresistant sublines. Subsequent analysis by quantitative RT-PCR confirmed the reliability of our microarray strategy. Up-regulated genes were associated with growth factor (example, amphiregulin), cell-cycle check point (MAPKAPK2), intracellular signaling pathway (regucalcin), and angiogenesis stimulation (angiopoietin 2). Down-regulated genes were associated with apoptosis (caspase 8), retinoid esterification (lecithin retinol acyltransferase), and electron transport (calcium-activated chloride channel 1). Some of these genes have known association with response to radiation, such as caspase 8 and MAPKAPK2, but others are novel. Global gene analysis of radioresistant sublines may provide new insights into the mechanisms underlying clinical radioresistance and to improving the efficacy of radiotherapy for pancreatic cancer.
鉴定在放射敏感和放射抗性癌细胞之间差异表达的基因对于预测放射治疗的临床效果至关重要。我们使用分次照射建立了放射抗性人胰腺癌细胞系，以鉴定亲代细胞系和放射抗性细胞亚系之间差异表达的基因。六个胰腺癌细胞系（PK-1、PK-8、PK-9、T3M4、MiaPaCa2和PANC-1）每隔约两周接受10 Gy分次照射（总剂量150-180 Gy）。成功建立了五个放射抗性亚系（PK-1、PK-8、PK-9、T3M4和MiaPaCa2）。使用包含17,086个基因的寡核苷酸微阵列，我们鉴定出放射抗性亚系共有的73个上调基因和55个下调基因。随后通过定量RT-PCR分析证实了我们微阵列策略的可靠性。上调基因与生长因子（例如 Amphiregulin）、细胞周期检查点（MAPKAPK2）、细胞内信号通路（Regucalcin）和血管生成刺激（血管生成素2）相关。下调基因与凋亡（半胱天冬酶8）、视黄醇酯化（卵磷脂视黄醇酰基转移酶）和电子传递（钙激活氯离子通道1）相关。其中一些基因已知与辐射反应有关，如半胱天冬酶8和MAPKAPK2，但其他一些是新发现的。对放射抗性亚系的全基因分析可能为临床放射抗性的潜在机制提供新见解，并有助于提高胰腺癌放射治疗的疗效。
