Compared to the cells transfected with the miR-203 agomir, the cells co-transfected with both the miR-203 agomir and let-7 antagomir exhibited a significantly increased proliferation rate and decreased apoptosis (Fig. S4), suggesting that miR-203 inhibits the proliferation and promotes the apoptosis of lung cancer cells by suppressing LIN28B and enhancing let-7 biogenesis. The gene discussed is LIN28B; the disease is lung cancer.