PDCD4 and urinary bladder carcinoma: In addition, Zhong et al. [91] reported that lncRNA PTENP1 “sponged” miR-20a to elevate the expression level of programmed cell death 4 (PDCD4), a tumor suppressor that induces apoptosis and inhibits cell growth, invasion, and metastasis [92], resulting in inhibition of the viability and migration of bladder cancer cells.