MALAT1 and prostate cancer: In addition, our findings also demonstrate the presence of a double-negative feedback loop between MALAT1 and miR-421; wherein MALAT1 sequesters miR-421 and averts its binding to target proteins, while miR-421 posttranscriptionally suppresses MALAT1, suggesting that reciprocal regulation between MALAT1 and miR-421 regulates the expression of HR genes in prostate cancer.