The present invention relates to compositions and methods for treating, characterizing and diagnosing ovarian cancer. In particular, the present invention provides methods for treating and/or preventing ovarian cancer in a subject by administering to the subject an effective amount of Mullerian Inhibiting substance and/or an effective amount of an agent that inhibits BCRP1. The present invention further provides methods to identify and/or enrich for populations of ovarian cancer stem cells and populations of somatic ovarian stem cells, in particular, enrichment for populations of coelomic somatic ovarian stem cells, subcoelomic/stromal somatic ovarian stem cells and periphilar medullary somatic ovarian stem cells. The present invention also provides somatic ovarian stem cell markers and ovarian cancer stem cell markers, as well as methods to identify agents which selectively inhibit the proliferation of ovarian cancer stem cells as compared to somatic ovarian stem cells.Linvention concerne des compositions et des méthodes de diagnostic, de caractérisation et de traitement du cancer de lovaire. Linvention concerne en particulier des méthodes de traitement et/ou de prévention du cancer de lovaire chez une patiente, par ladministration dune quantité efficace dune substance anti-Müllérienne et/ou dune quantité efficace dun agent qui inhibe BCRP1. Linvention concerne également des méthodes permettant didentifier et/ou denrichir des populations de cellules souches cancéreuses ovariennes et des populations de cellules souches somatiques ovariennes, en particulier denrichir des populations de cellules souches somatiques ovariennes coelomiques, de cellules souches somatiques ovariennes sous-coelomiques/stromales et de cellules souches somatiques ovariennes médullaires périphilaires. Linvention concerne encore des marqueurs de cellules souches somatiques ovariennes et des marqueurs de cellules souches cancéreuses ovariennes, ainsi que des méthodes didentification dagents inhi
