A study in humans demonstrated that the mir-660 was significantly downregulated in the prefrontal cortex of antidepressant-free depressed suicide subjects compared to non-psychiatric controls, with expression measured at 0.811 of control (p=0.0277) [Smalheiser et al. DOI:10.1371/journal.pone.0033201]. A study in humans demonstrated that the mir-660 was downregulated in the BA9 region of the brain in subjects with major depressive disorder who died by suicide [Yoshino & Dwivedi DOI:10.3389/fpsyt.2020.543893]. In a separate human study investigating sacubitril/valsartan resistance in heart failure patients, the mir-660 was identified as a potential biomarker, though its expression change was not consistent with initial microarray data during qRT-PCR validation in peripheral blood mononuclear cells [Su et al. DOI:10.1016/j.ejphar.2023.175547].