L lines (ARK1 and ARK2) were kindly provided by Dr. Alessandro

L lines (ARK1 and ARK2) were kindly provided by Dr. Alessandro Santin (Yale School of Table 3. Co-occurrence of ESCO1 mutations with CHTF18 or ATAD5 mutations in EC.Identification of orthologous genesA consolidated list of known and candidate human orthologues of yeast chromosome stability genes (with demonstrated roles in sister chromatid cohesion) was identified through standard crossspecies approaches. Briefly, InParanoid 7 and HomoloGene databases were queried to identify known orthologues, while BLASTp was employed to identify the top-hit candidates (based on E-value) from the non-redundant protein sequences within the Homo sapiens database.Mutation Status CHTF18-mutated (n = 2) CHTF18-nonmutated (n = 105) ATAD5-mutated (n = 5) ATAD5-nonmutated (n = 102)No. of ESCO1-mutated P-value1 Cases ( ) 2 (100 ) 2 (1.90 ) 2 (40 ) 2 (1.96 ) P = 0.0102 P = 0.1 Two-tailed Fisher’s exact test. doi:10.1371/journal.pone.0063313.tCohesion Gene Mutations in Endometrial CancerMedicine). Endometrioid endometrial cancer cell lines (RL-95-2, HEC1A, HEC1B, ANC3A) and a cell line derived from a poorly differentiated endometrial adenocarcinoma (KLE) were obtained from the American Type Culture Collection, or the NCI Developmental Therapeutics Program cell line repository. Cells were washed in phosphate-buffered saline followed by lysis in icecold RIPA buffer (Thermo Scientific) containing 1 mM Naorthovanadate, 10 mM NaF, and 1X protease inhibitor cocktail (Roche). Lysates were centrifuged and equal amounts of the cleared lysate were denatured at 95uC in 26 SDS sample buffer (Sigma) prior to SDS-PAGE and transfer to PVDF membranes (Bio-Rad). Primary and HRP-conjugated secondary antibodies were: aMRE-11 (Cell Signaling), aCHTF18 (Novus Biological), aESCO1 (Novus Biological), a-a/b-Tubulin (Cell Signaling), goat anti-mouse HRP (Cell Signaling), and goat anti-rabbit HRP (Cell Signaling). Immunoreactive proteins were visualized with enhanced chemiluminescence (Pierce).mutationassessor.org/), SIFT (http://sift.jcvi.org/), and Polyphen2 (http://genetics.bwh.harvard.edu/pph2/index.shtml).Calculation of discovery screen powerThe estimated power to detect one gene mutation in a set of 24 ^ tumors is 1?(1-X)24, where X is the actual fraction of tumors with a mutation in that gene.Results and DiscussionIn 23148522 a mutation discovery screen, we analyzed 24 primary NEECs for the presence of nucleotide variants within the coding exons and splice junctions of 21 candidate chromosome instability genes, which are expressed, at variable levels, in endometrial cancer cell lines (Figure S1). Nineteen of these genes are implicated in the regulation of sister-chromatid cohesion, based on their sequence homology to cohesion genes in S. cerevisiae (Table 1). The 24 NEECs consisted of 17 serous ECs and 7 clear cell ECs; five of the serous tumors (T33, T45, T65, T69, T70) were recently subjected to whole exome sequencing [52]. We included only MSI-stable tumors in the discovery screen; the MSI data have been reported elsewhere [52]. We obtained high inhibitor quality sequence data for 87.6 (5.64 Mb) of bases (6.44 Mb) targeted. After excluding variants that were annotated as single nucleotide polymorphisms (SNPs) within dbSNP (Build 129), there were 109 unique nucleotide variants that represented potential somatic mutations. To determine whether these variants were somatic mutations or germline variants, we reamplified and sequenced the variant positions from the appropriate tumor DNA and matched no.L lines (ARK1 and ARK2) were kindly provided by Dr. Alessandro Santin (Yale School of Table 3. Co-occurrence of ESCO1 mutations with CHTF18 or ATAD5 mutations in EC.Identification of orthologous genesA consolidated list of known and candidate human orthologues of yeast chromosome stability genes (with demonstrated roles in sister chromatid cohesion) was identified through standard crossspecies approaches. Briefly, InParanoid 7 and HomoloGene databases were queried to identify known orthologues, while BLASTp was employed to identify the top-hit candidates (based on E-value) from the non-redundant protein sequences within the Homo sapiens database.Mutation Status CHTF18-mutated (n = 2) CHTF18-nonmutated (n = 105) ATAD5-mutated (n = 5) ATAD5-nonmutated (n = 102)No. of ESCO1-mutated P-value1 Cases ( ) 2 (100 ) 2 (1.90 ) 2 (40 ) 2 (1.96 ) P = 0.0102 P = 0.1 Two-tailed Fisher’s exact test. doi:10.1371/journal.pone.0063313.tCohesion Gene Mutations in Endometrial CancerMedicine). Endometrioid endometrial cancer cell lines (RL-95-2, HEC1A, HEC1B, ANC3A) and a cell line derived from a poorly differentiated endometrial adenocarcinoma (KLE) were obtained from the American Type Culture Collection, or the NCI Developmental Therapeutics Program cell line repository. Cells were washed in phosphate-buffered saline followed by lysis in icecold RIPA buffer (Thermo Scientific) containing 1 mM Naorthovanadate, 10 mM NaF, and 1X protease inhibitor cocktail (Roche). Lysates were centrifuged and equal amounts of the cleared lysate were denatured at 95uC in 26 SDS sample buffer (Sigma) prior to SDS-PAGE and transfer to PVDF membranes (Bio-Rad). Primary and HRP-conjugated secondary antibodies were: aMRE-11 (Cell Signaling), aCHTF18 (Novus Biological), aESCO1 (Novus Biological), a-a/b-Tubulin (Cell Signaling), goat anti-mouse HRP (Cell Signaling), and goat anti-rabbit HRP (Cell Signaling). Immunoreactive proteins were visualized with enhanced chemiluminescence (Pierce).mutationassessor.org/), SIFT (http://sift.jcvi.org/), and Polyphen2 (http://genetics.bwh.harvard.edu/pph2/index.shtml).Calculation of discovery screen powerThe estimated power to detect one gene mutation in a set of 24 ^ tumors is 1?(1-X)24, where X is the actual fraction of tumors with a mutation in that gene.Results and DiscussionIn 23148522 a mutation discovery screen, we analyzed 24 primary NEECs for the presence of nucleotide variants within the coding exons and splice junctions of 21 candidate chromosome instability genes, which are expressed, at variable levels, in endometrial cancer cell lines (Figure S1). Nineteen of these genes are implicated in the regulation of sister-chromatid cohesion, based on their sequence homology to cohesion genes in S. cerevisiae (Table 1). The 24 NEECs consisted of 17 serous ECs and 7 clear cell ECs; five of the serous tumors (T33, T45, T65, T69, T70) were recently subjected to whole exome sequencing [52]. We included only MSI-stable tumors in the discovery screen; the MSI data have been reported elsewhere [52]. We obtained high quality sequence data for 87.6 (5.64 Mb) of bases (6.44 Mb) targeted. After excluding variants that were annotated as single nucleotide polymorphisms (SNPs) within dbSNP (Build 129), there were 109 unique nucleotide variants that represented potential somatic mutations. To determine whether these variants were somatic mutations or germline variants, we reamplified and sequenced the variant positions from the appropriate tumor DNA and matched no.