In ovarian cancer, Let-7 is a family of tumor suppressor miR, inhibiting a downstream component of the EGFR signaling network (KRAS), regulating cancer-cell proliferation [115], protein that belongs to the non-histone chromosomal high-mobility group (HMGA2) associated with both malignant and benign tumor formation, as well as certain characteristic cancer-promoting mutations [116] and c-Myc [117]; then Let-7 has been identified as a potential maker for early diagnosis [118]. This evidence concerns the gene KRAS and cancer.