Locked nucleic acid in situ hybridization analysis of miR-21 expression during colorectal cancer development

Nobutake Yamamichi, Ryoichi Shimomura, Ken Ichi Inada, Kouhei Sakurai, Takeshi Haraguchi, Yuka Ozaki, Shuji Fujita, Taketoshi Mizutani, Chihiro Furukawa, Mitsuhiro Fujishiro, Masao Ichinose, Kazuya Shiogama, Yutaka Tsutsumi, Masao Omata, Hideo Iba

研究成果: Article査読

170 被引用数 (Scopus)

抄録

Purpose: To better understand microRNA miR-21 function in carcinogenesis, we analyzed miR-21 expression patterns in different stages of colorectal cancer development using in situ hybridization (ISH). Experimental Design: Locked nucleic acid (LNA)/DNA probes and a biotin-free tyramide signal amplification system were used in ISH analyses of miRNA expression. Conditions for specific detection of miR-21 were determined using human cell lines and miR-21-expressing lentiviral vectors. Expression was determined in 39 surgically excised colorectal tumors and 34 endoscopically resected colorectal polyps. Results: In the surgical samples, miR-21 expression was much higher in colorectal cancers than in normal mucosa. Strong miR-21 expression was also observed in cancer-associated stromal fibroblasts, suggesting miR-21 induction by cancer-secreted cytokines. Protein expression of PDCD4, a miR-21 target, was inversely correlated with miR-21 expression, confirming that miR-21 is indeed a negative regulator of PDCD4 in vivo. In the endoscopic samples, miR-21 expression was very high in malignant adenocarcinomas but was not elevated in nontumorigenic polyps. Precancerous adenomas also frequently showed miR-21 up-regulation. Conclusion: Using the LNA-ISH system for miRNA detection, miR-21 was detectable in precancerous adenomas. The frequency and extent of miR-21 expression increased during the transition from precancerous colorectal adenoma to advanced carcinoma. Expression patterns of miR-21 RNA and its target, tumor suppressor protein PDCD4, were mutually exclusive. This pattern may have clinical application as a biomarker for colorectal cancer development andmight be emphasized by self-reinforcing regulatory systems integrated with the miR-21 gene, which has been previously shown in cell culture.

本文言語English
ページ(範囲)4009-4016
ページ数8
ジャーナルClinical Cancer Research
15
12
DOI
出版ステータスPublished - 15-06-2009

All Science Journal Classification (ASJC) codes

  • 腫瘍学
  • 癌研究

フィンガープリント

「Locked nucleic acid in situ hybridization analysis of miR-21 expression during colorectal cancer development」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル