PGR and ovarian serous carcinoma: Several previous studies demonstrated PR expression as a biomarker to predict better prognosis of endometrioid and high-grade serous ovarian carcinoma (Jonsson et al., 2015; Lee et al., 2005; Lenhard et al., 2012; Sieh et al., 2013), while lost PR expression was associated with advanced stages of ovarian cancer (Feng et al., 2016).