Liang et al. explained in detail some of the miRs that are involved in drug resistance, which include miR-326,40 miR-328 and miR-34a.39 It is determined that miR-31a is a straight target of p53,31 “miR-21 overexpression is associated with the development and progression of multidrug resistance in breast cancer” and hopefully also rising as an original and optimistic reversing target.31,40. The gene discussed is TP53; the disease is breast cancer.