microRNA inhibits prostate cancer metastasis by suppressing a surface protein (CD44) commonly found on prostate cancer stem cells. A research team led by scientists at The University of Texas MD Anderson Cancer Center reported in an advance online publication at Nature Medicine1.
The researchers demonstrated that miR-34a inhibits prostate cancer stem cells by suppressing CD44 and most significantly, that intravenous treatment of tumor-bearing mice with synthetic miR-34a reduced tumor burden by half in one tumor type. It also steeply reduced lung metastases in another tumor type, resulting in increased animal survival.
In a previous groundbreaking study, researchers at Memorial Sloan-Kettering Cancer Center found a specific set of microRNAs for which expression is specifically lost as human breast cancer cells develop metastatic potential2. Furthermore, they show that restoring the expression of these microRNAs in malignant cells reduces overall tumor growth and proliferation and suppresses metastatic cell invasion.
1. Liu C, Kelnar K, Liu B, Chen X, Calhoun-Davis T, Li H, Patrawala L, Yan H, Jeter C, Honorio S, Wiggins JF, Bader AG, Fagin R, Brown D, Tang DG. (2011) The microRNA miR-34a inhibits prostate cancer stem cells and metastasis by directly repressing CD44. Nat Med [Epub ahead of print]. [abstract]
2. Tavazoie SF, Alarcón C, Oskarsson T, Padua D, Wang Q, Bos PD, Gerald WL, Massagué J. (2008) Endogenous human microRNAs that suppress breast cancer metastasis. Nature 451(7175), 147-52. [abstract]
MDACC News Release 1/16/11
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