Page 246 - ebook

[D. Medicine/Translational Research] D-7

High-metastatic Potential MicroRNAs in Human Colorectal

Cancer

Hagyeong Lee¹,², Eun Hwangbo¹,², Huiwon Do³, Yu Rim Lee⁴, Se Young Jang⁴, Min Kyu Kang⁵, Jung Gil

Park⁵, Hye Won Lee⁶, Won Young Tak⁴, Soo Young Park⁴, Keun Hur¹,²*

¹Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Daegu 41944,

Korea, ²BK21 Plus KNU Biomedical Convergence Program, Department of Biomedical Science, Kyungpook National
University, Daegu 41566, Korea, ³Department of Biomedical Convergence Science and Technology, School of

Convergence, Kyungpook National University, Daegu 41566, Korea, ⁴Department of Internal Medicine, School of
Medicine, Kyungpook National University, Daegu 41944, Korea, ⁵Department of Internal Medicine, College of

Medicine, Yeungnam University, Daegu 42415, Korea

Over the 50% of colorectal cancer (CRC) patients undergo distant metastasis, which is a major cause of high mortality
rate. Epithelial-to-mesenchymal transition (EMT) is an initial and essential step for cancer metastasis. MicroRNAs

(miRNAs) have been identified as upstream regulator in cancer metastasis and EMT-related genes. In this study, we
aimed to discover miRNAs which are highly associated with CRC metastasis. To induce in vitro EMT-induction system,

SW480 (CRC cell line) was treated with TGF-β. Total RNAs were isolated from CRC cell line and paired exosome.
Total miRNAs were extracted from CRC patients' serum. The miRNAs expression pattern was identified using

nanoString nCounter analysis and validated using qRT-PCR. In comparison between parental SW480 and EMT-
induced SW480, 6 up-regulated and 55 down-regulated miRNAs in EMT-induced SW480 were discovered. Through

the validation process, up-regulated hsa-miR-29a-3p and hsa-miR-29b-3p were identified as EMT-specific miRNAs.
In clinical validation analysis using serum samples from CRC patients, hsa-miR-29a-3p was significantly increased in

CRC patients with distant metastasis compared to patients without metastasis. In the present study, high level of
miR-29a-3p was associated with EMT status as well as metastasis status. This unique miRNA may serve as a potential

biomarker for predicting metastasis of CRC patients.