Taken together, these results suggest that although miR-182 is expressed at higher levels in localized prostate cancer, its levels are lower in aggressive cancers, suggesting a biphasic role for this miRNA that may be exploited for prognostic and/or therapeutic purposes to reduce prostate cancer progression.
In vitro studies revealed that overexpression of miR-182 promoted cell proliferation, colony formation, migration, invasion and inhibited cell apoptosis; in vivo results demonstrated that silencing of miR-182 mediated by inhibitor dramatically reduced prostate cancer xenograft tumor growth.
In this regard, we suggest that miR-182-5p may be a key androgen receptor-regulated factor that contributes to the development and metastasis of Chinese prostate cancers and may be a potential target for the early diagnosis and therapeutic studies of prostate cancer.
RESULTS A total of 162 miRNAs were differentially expressed between normal and prostate cancer samples, including 128 up-regulated and 38 down-regulated ones; hsa-mir-153-2, hsa-mir-92a-1, and hsa-mir-182 (up-regulated); and hsa-mir-29a, hsa-mir-10a, and hsa-mir-221 (down-regulated) were identified as good biomarkers.
Comparing with the other 18 types of cancers listed in The Cancer Genome Atlas Data Portal, we found that the combination of both miRNA-182 and miRNA-200c being up-regulated and miRNA-221 being down-regulated only happens in prostate cancer.
Results show that miR-182 and 187 are promising biomarkers for prostate cancer prognosis to identify patients at risk for progression and for diagnosis to improve the predictive capability of existing biomarkers.
In conclusion this is the first report documenting that over-expression of miR-182-5p is associated with prostate cancer progression and potentially useful as a prognostic biomarker.
Overexpressed microRNA-182 promotes proliferation and invasion in prostate cancer PC-3 cells by down-regulating N-myc downstream regulated gene 1 (NDRG1).