ABCB1 and ovarian carcinoma: Xing et al (2007) recently reported that knock down of P-glycoprotein reverses taxol resistance in ovarian cancer multicellular spheroids. An increased expression of MDR1 was found to be associated with an unfavourable prognosis of ovarian cancer in some studies (Materna et al, 2004; Penson et al, 2004), but not in others (Yokoyama et al, 1999; Ozalp et al, 2002).