PRDM9 and ovarian serous adenocarcinoma: To this end, nuclei were isolated following an optimized protocol for single nuclei RNA sequencing53 and sorted from a serous ovarian cancer cell line PEO1 treated with tazemetostat, a clinically approved epigenetic inhibitor of the histone methyltransferase EZH2 that methylates lysine 27 of histone 3.154 (Fig. 5a).