Correlation of over-expressions of miR-21 and Notch-1 in human colorectal cancer with clinical stages.
OBJECTIVE
The aim of the study was to identify expressions of Notch-1, microRNA-21 (miR-21), and phosphatase and tensin homolog (PTEN) in colorectal cancer (CRC), and to explore their relationship with clinical stages and metastatic status of CRC.


METHODS
102 CRC patients were enrolled and clinical data were analyzed. Expressions of Notch-1 and miR-21 in CRC and adjacent non-tumor tissues of these patients were measured by real time-PCR. Protein expressions of Notch-1 and PTEN of 12 paired tissues were determined by Western blot and immunohistochemistry. The correlations between gene expressions in different clinical stages as well as metastatic status were evaluated by linear regression.


RESULTS
Notch-1 was over-expressed in 86.27% (88/102) CRC tissues, particularly in advanced stages, while miR-21 expression was increased to 74.51% (76/102) in CRC tissues compared with matched adjacent non-tumor tissues. The expressions of Notch-1 and miR-21 were positively correlated with CRC development, especially in advanced-stages (r(2)=0.3839, p<0.01). Expressions of PTEN were significantly down-regulated in CRC tissues and negatively correlated with expressions of Notch-1 (r(2)=0.5207, p<0.01) and miR-21 (r(2)=0.6996, p<0.01).


CONCLUSIONS
These data indicate that the crosstalk between Notch-1 and miR-21 is involved in CRC development through degradation of PTEN.
Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China.
Yao
Y
Xiong
Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China.
Yuan-Yuan
YY
Zhang
Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China; Department of Pharmacology, School of Pharmacy, Chengdu Medical College, Chengdu, Sichuan 610083, PR China.
Yi-Ying
YY
Wu
Department of Gastrointestinal Surgery Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, PR China.
Xiao-Dong
XD
Wang
Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China.
Li-Hong
LH
Wan
Department of Gastrointestinal Surgery Center, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, PR China.
Li-
L
Li
Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan 610041, PR China; 985 Science and Technology Platform for Innovative Drugs, Sichuan University, Chengdu, Sichuan 610041, PR China. Electronic address: zhoulm01@163.com.
Li-Ming
LM
Zhou
D000368:Aged; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000096:biosynthesis*; D008875:Middle Aged; D009367:Neoplasm Staging; D051881:Receptor, Notch1 / Q000096:biosynthesis*
C524940:MIRN21 microRNA, human; D035683:MicroRNAs; C497761:NOTCH1 protein, human; D051881:Receptor, Notch1
Clinic stages; Colorectal cancer; Notch-1; PTEN; miR-21