Zhang Jianjun, Zafrullah Mohammad, Yang Xia, Yin Xianglei, Zhang Zhigang, Fuks Zvi, Kolesnick Richard
Laboratory of Signal Transduction, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
Cancer Biol Ther. 2008 Sep;7(9):1490-5. doi: 10.4161/cbt.7.9.6472. Epub 2008 Sep 15.
While antisense oligonucleotide (AS-ODN) technology holds promise for the treatment of cancer, to date there have been no clinical successes. Unfortunately, current assays are not sufficiently sensitive to measure tissue ODN levels. Hence it has not been possible to ascertain whether treatment failures result from failure of drug delivery. To investigate the relationship between drug uptake and therapeutic effect, we developed an ultrasensitive noncompetitive hybridization-ligation enzyme-linked immunosorbent assay (NCHL-ELISA) to quantify Kinase Suppressor of Ras1 (KSR1) AS-ODN drug uptake in plasma and tumor tissues. In mice harboring PANC-1 pancreatic cancer xenografts and continuously infused with AS-ODN, our ELISA detects plasma and tumor KSR1 AS-ODN levels over an extended range, from 0.05 nM to 20 nM. Using this sensitive assay, we demonstrate that KSR1 repression in pancreatic cancer xenografts correlates highly with AS-ODN uptake into tumor tissues. In contrast, plasma drug levels do not correlate with tumor drug content or target downregulation. These studies indicate the efficacy of our ELISA, and suggest that tumor biopsy material will need to be procured to estimate the potential of this antisense technology.
虽然反义寡核苷酸（AS-ODN）技术有望用于癌症治疗，但迄今为止尚未取得临床成功。不幸的是，目前的检测方法不够灵敏，无法测量组织中的ODN水平。因此，尚无法确定治疗失败是否是由于药物递送失败所致。为了研究药物摄取与治疗效果之间的关系，我们开发了一种超灵敏的非竞争性杂交连接酶联免疫吸附测定法（NCHL-ELISA），用于定量血浆和肿瘤组织中Ras1激酶抑制因子（KSR1）AS-ODN的药物摄取。在携带PANC-1胰腺癌异种移植瘤并持续输注AS-ODN的小鼠中，我们的ELISA可在0.05 nM至20 nM的广泛范围内检测血浆和肿瘤中的KSR1 AS-ODN水平。使用这种灵敏的检测方法，我们证明胰腺癌异种移植瘤中KSR1的抑制与AS-ODN摄取到肿瘤组织中高度相关。相比之下，血浆药物水平与肿瘤药物含量或靶点下调无关。这些研究表明了我们ELISA的有效性，并提示需要获取肿瘤活检材料来评估这种反义技术的潜力。
