NFKB1 and ovarian cancer: However, TAK1 variable exon 12 exerted opposite function that constitutively supported TGF-β-induced EMT and activated nuclear factor-kappa B (NF-κB) signaling pathway, eventually causing chemotherapeutic resistance.25 Breast and ovary cancer cells can overcome deleterious germline mutations in BRCA1 (the gene encoding breast cancer type-1 susceptibility protein) by alternative splicing.