Identification of a new microRNA expression profile as a potential cancer screening tool.
OBJECTIVE
Small non-coding microRNAs (miRNAs) are key components of cancer development and are considered as potential biomarkers for cancer diagnosis and treatment monitoring. This study investigated miRNA expression profiles of human cancer cells in order to develop a screening method for lung cancer.


METHODS
A series of lung cancer related miRNAs (miR-21, miR-145, miR-155, miR-205, miR-210, miR-92, miR-17-5p, miR-143, miR-182, miR-372, let-7a) were selected as candidates for miRNA expression profiles of human lung cancer cell lines (A549, SK-mes-1). MicroRNA u6 was the endogenous control. Cancer cell lines for positive controls; breast MCF-7, prostate Du-145, and glioblastoma U118. The negative control was normal lung fibroblast cell line MRC-5. RT-PCR was performed on StepOnePlus (Applied Biosystem, USA). MiRNA expressions of malignant cells were compared with normal fibroblast cells as well as endogenous control (u6) using the thermal cycle at threshold. Assessment of miRNA expression profiles were then performed using agglomerative hierarchical cluster analysis software (SPSS13, USA).


RESULTS
We demonstrated that miR-21, miR-182 and let7-5a were over-expressed, and miR-145 and miR-155 were under-expressed in all cancer cell lines. Combined with the cluster analysis we were able to clearly distinguish cell lines for normal fibroblasts, breast cancer, prostate cancer, glioblastoma, and lung cancer.


CONCLUSIONS
There is potential utility of screening for lung cancer with miRNA expression profiles. Future work will focus on the sensitivity of such miRNA expression profiles in screening sputum for lung cancer, which can be performed in real time.
Roa
Wilson
W
Alberta Laboratory for Environmental Cancer Risk & Assessment, Alberta, Canada.
Brunet
Bryan
B
Guo
Linghong
L
Amanie
John
J
Fairchild
Alysa
A
Gabos
Zsolt
Z
Nijjar
Tirath
T
Scrimger
Rufus
R
Yee
Don
D
Xing
James
J
D045744:Cell Line, Tumor; D016000:Cluster Analysis; D015536:Down-Regulation / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics / Q000378:metabolism; D009369:Neoplasms / Q000175:diagnosis* / Q000235:genetics*; D012342:RNA, Small Nuclear / Q000032:analysis / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015854:Up-Regulation / Q000235:genetics
D035683:MicroRNAs; D012342:RNA, Small Nuclear; C541010:MIRN145 microRNA, human; C524942:MIRN155 microRNA, human; C534425:MIR205, human; C524940:MIRN21 microRNA, human; C541874:MIRN92 microRNA, human; C538984:Mirn182 microRNA, human; C405486:U6 small nuclear RNA; C487931:mirnlet7 microRNA, human