It has been widely established that miR-21 promotes survival and proliferation of cancer cells by directly inhibiting its targets, including PTEN, Programmed Cell Death 4 (PDCD4), reversion-inducing-cysteine-rich protein with kazal motifs (RECK), and sprouty RTK signaling antagonist 2 (SPRY2). The gene discussed is RECK; the disease is cancer.