Identification of microRNA that correctly inhibits KRAS-related downstream signal transduction in KRAS mutant colorectal cancer

鉴定正确抑制 KRAS 突变结直肠癌中 KRAS 相关下游信号转导的 microRNA

• 批准号: 24659608
• 负责人: YAMAMOTO Hirofumi
• 金额: $ 2.33万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Challenging Exploratory Research
• 财政年份: 2012
• 资助国家: 日本
• 起止时间: 2012-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-24659608/
• 关键词: KRAS; colorectal cancer; microRNA; RAF/MEK/ERK pathway; PI3K/Akt pathway; carbonate apatite; nanoparticle; AKT; 大腸癌; K-ras遺伝子変異; セツキシマブ; MAPK/ERK; AP-１

The antiEGFR monoclonal antibodies are effective in patients with metastatic CRC with KRAS wild type. However, KRAS mutant mCRC shows resistance to the antiEGFR antibodies. To identify miRNAs that inhibit KRAS mutant CRCs, we first introduced KRASG12V cDNA into HEK293 and MRC5. After miRNA microarray analyses we searched which candidate miRNAs would inhibit two major KRAS-associated signal transduction pathways using SRE and AP1 luciferase reporter assays. And we found 2 miRNAs. miR-4689 regulated not only RAF/MEK/ERK pathway but also PI3K/Akt pathway by directly binding to both 3UTR of KRAS and the coding sequence of Akt1. Down-regulation of Akt1 led to sequential induction of pro-apoptotic factors and inhibition of anti-apoptotic molecules. Systemic administration of miR-4689 with super carbonate apatite nanoparticles in nude mice significantly inhibited the growth of pre-established DLD1 xenografts compared to miR-NC with a proof of down-regulation of KRAS and Akt1.

抗EGFR单克隆抗体在KRAS野生型转移性CRC患者中有效。然而，KRAS突变型mCRC显示出对抗EGFR抗体的耐药性。为了鉴定抑制KRAS突变CRC的miRNA，我们首先将KRASG 12 V cDNA引入HEK 293和MRC 5中。在miRNA微阵列分析后，我们使用SRE和AP 1荧光素酶报告基因分析来寻找哪些候选miRNA会抑制两种主要的KRAS相关信号转导途径。我们发现了2个miRNAs。miR-4689通过与KRAS的3UTR和Akt 1的编码序列直接结合，不仅调节RAF/MEK/ERK通路，还调节PI 3 K/Akt通路。Akt 1的下调导致促凋亡因子的连续诱导和抗凋亡分子的抑制。与miR-NC相比，在裸鼠中全身给予miR-4689和超碳酸盐磷灰石纳米颗粒显著抑制了预先建立的DLD 1异种移植物的生长，并证明了KRAS和Akt 1的下调。

项目成果

大腸癌の治療剤

结直肠癌的治疗

• 发表时间: 2014