Additionally, ectopic miR-let-7 cluster expression can weaken DDP resistance in ovarian cancer cells by inhibiting high mobility group AT-hook 1 (HMGA1), RAD51 recombinase (RAD51), and BRCA1, indicating that the miR-let-7 cluster might be a candidate biomarker to predict ovarian cancer responders to DDP treatment (Xiao et al., 2017; Chen Y. N. et al., 2019). This evidence concerns the gene BRCA1 and ovarian cancer.