ROCK1 and Familial prostate cancer: In the same year, Kosaka et al. [148] studied the ability of an exosome-transferred miRNA known to be downregulated in prostate cancer (miR-146a) to restore conditions of growth inhibition in recipient cells; they found that miR-146a was not only able to inhibit cell growth, but did so by knocking down the Rho-associated protein kinase 1 (ROCK1), a known target gene for miR-146a [148].