Aberrant expression of miR-203 and its clinical significance in gastric and colorectal cancers.
BACKGROUND
MicroRNAs (miRNAs) are small, non-coding RNAs of endogenous origin, they have been increasingly shown to have aberrant expression in many tumor types. miR-203 has not been comprehensively investigated in gastric and colorectal cancers.


METHODS
Total RNA was extracted from tissues of 212 patients with gastric or colorectal cancer as well as from seven gastric and colorectal cell lines. We determined the expression of miR-203 by real-time PCR and calculated using the 2-ΔΔCt method. Then, we assessed miR-203 expression and clinicopathologic characteristics. Finally, we studied the effect of miR-203 on cell proliferation in SGC-7901 cells by MTT.


RESULTS
miR-203 has significantly low expression in colorectal cancer tissues (p < 0.001, paired t test) and cancer cell lines compared to non-tumor counterparts. Moreover, low expression of miR-203 was correlated with tumor size (p = 0.015, non-parametric test) and pT stage (p = 0.005) in colorectal cancer. Although expression of miR-203 was not significant in gastric cancer tissues (p = 0.124), interestingly, miR-203 was correlated with tumor size (p = 0.023), macroscopic type (p = 0.045), and pT stage (p = 0.013). Furthermore, we found miR-203 can inhibit the cell proliferation in SGC-7901 cells.


CONCLUSIONS
miR-203 may be related to the proliferation and invasion of gastric and colorectal cancers.
Department of Surgical Oncology and General Surgery, First Hospital of China Medical University, Shenyang, 110001, People's Republic of China.
Yeunpo
Y
Chiang
Yongxi
Y
Song
Zhenning
Z
Wang
Yue
Y
Chen
Zhenyu
Z
Yue
Huimian
H
Xu
Chengzhong
C
Xing
Zhuangkai
Z
Liu
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000235:genetics*; D009367:Neoplasm Staging; D012334:RNA, Neoplasm / Q000235:genetics*; D012189:Retrospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology; D055815:Young Adult
C546703:MIRN203 microRNA, human; D035683:MicroRNAs; D012334:RNA, Neoplasm