Expression And Its Significance Of 10 MicroRNAs In Prostate Cancer

Background & Objective MicroRNA (miRNA) is a kind of naturally occurring small non-coding RNA containing 20 to 23 nucleotides in length. The experimental evidence supported an indispensable role of miRNA in some physiological and pathological processes,especially in the initiation and progression of human malignancies. The present research was undertaken to evaluate the differential expression of 10 miRNAs in prostate cancer and its significance, and further determine whether the expression profiles consisted of 10 miRNAs could be used as novel biomarkers for early detection and prognostic assessment of prostate cancer.Methods: The expression profiling of these 10 miRNAs were investigated using the method of locked nucleic acid (LNA)-modified oligonucleotide in situ hybridization(ISH).And the technology of tissue microarray(TMA) was employed using the formalin-fixed, paraffin-embedd (FFPE) specimens taken from 52 patients with prostate cancer and 38 patients with benign prostatic hyperplasia.Results: 1.Compared with benign prostatic hyperplasia,the expression of 7 miRNAs decreased in prostate cancer, including miR-15b,miR-16,let-7g,let-7d,miR-101,miR- 126 and miR-98,however,the expression of miR-96,miR-182 and miR-183 increased in prostate cancer. So the expressions of all 10 miRNAs between the prostate cancer and benign prostatic hyperplasia tissues were significantly different(P<0.05). 2.The positive rate of these 10 miRNAs was significantly related to the Gleason Grading of prostate cancer (P<0.05).There was no significant correlation between the expression of these miRNAs and age and the concentration of serum PSA of the patient(P>0.05). We also found that the expression of miR-15b,miR-96,miR-182 and miR-126 correlated with clinical stages of tumor (P <0.05). In addition,the expression of miR-96,miR-126 and miR-98 correlated with lobus prostatae of tumor invasion (P < 0.05). 3.The expression of miR-15b was related to that of miR-96, miR-182 and miR-183 in prostate cancer,respectively(P<0.01,r=0.39;P<0.05,r=0.31;P<0.01,r=0.38).There was a significant correlation among the expressions of miR-96,miR-182 and miR-183 in prostate cancer(P<0.01,r=0.38;P<0.01,r=0.45;P<0.01,r=0.51).In addition,the expression of let-7d was related to that of let-7g(P<0.01,r=0.37),and there was also a correlation between the expression of miR-16 and let-7g(P<0.01, r=0.54),so was between the expression of let-7d,let-7g and miR-98(P<0.01,r=0.37;P<0.01,r=0.46).There were no significant correlations between the expression of other miRNAs we studied in prostate cancer(P>0.05).Conclusion The results suggest that miRNAs are involved in the initiation and progression of prostate cancer and miRNA expression profiling could have relevance to the biological and clinical behavior of prostate cancer.The expression profiles consisted of several miRNAs is contributed to the pathological diagnosis and grading of prostate cancer, they might be novel biomarkers for early detection and prognostic assessment of prostate cancer.