WIF1 and ovarian carcinoma: DKK1 is induced by p53 because the Dkk1 transcription start site has a p53 responsive element (Caricasole et al., 2004[9]; Wang et al., 2000[58]), whereas DKK1 and Wnt inhibitory factor-1 (WIF1) significantly activated the transcription of p53 in ovarian carcinoma cells (Ko et al., 2014[30]).