BRCA1 and ovarian cancer: Both PARP1 and IGF-1 are potential direct targets of let-7e according to miRWalk and microRNA.org, our study showed that let-7e negatively regulated the expression of PARP1 and IGF-1 in ovarian cancer cell lines, indicating that PARP1 and IGF-1 might link let-7e to Rad51 and BRCA1, although that remains to be verified in further studies.