Further, the overexpression of miRNA-21 in IHD was seen to be associated with the apoptosis regulatory proteins [B-cell lymphoma 2 (BCL-2)] and phosphatase and tensin homolog (PTEN), suggesting an additional role as a regulator of the cell cycle in stress responses, as demonstrated in a study examining patients with stable, unstable angina and controls (26). Here, PTEN is linked to angina unstable.