Project description:Full title: comparison of the genomic (arrayCGH) profiles of endometrial cancer with and without prior prolonged tamoxifen treatment for primary breast cancer Purpose: Tamoxifen has been a very effective treatment for breast cancer for several decades, however, at the same time increases the risk of endometrial cancer, especially after prolonged exposure. In addition, tamoxifen has been associated with a higher proportion of unfavorable uterine tumor subtypes (carcinosarcomas and serous adenocarcinomas) with worse survival. We investigated whether endometrial tumors, which developed after prolonged tamoxifen treatment for breast cancer, are genetically different from endometrial tumors without preceding tamoxifen exposure. Experimental design: Array CGH was used on archival formalin-fixed paraffin embedded (FFPE) endometrial tumors to determine genomic aberrations. We compared the genomic profiles of 52 endometrial tumors from breast cancer patients after long-term (>=2 years) tamoxifen use (endometrioid adenocarcinomas n=26, carcinosarcomas n=14 and serous adenocarcinomas n=12) with endometrial tumors from unexposed breast cancer patients (n=45). Genomic profiles were correlated with tamoxifen exposure, tumor subtypes and histopathological characteristics of the endometrial tumors. Results: The common uterine corpus cancers of the endometrioid subtype show few genomic aberrations. Tumors with many genomic aberrations were in general ER-negative. In contrast, carcinosarcomas and serous adenocarcinomas showed many aberrations, however they were indistinguishable from each other. Tumors that developed after prolonged tamoxifen use did not show more or different aberrations than unexposed tumors. This was true for all tumor subtypes. Conclusion: Endometrial carcinomas that develop after prolonged tamoxifen use can not be distinguished from non-users on basis of their tumor genomic profile. 52 endometrial tumors from breast cancer patients after long-term (>=2 years) tamoxifen use (endometrioid adenocarcinomas n=26, carcinosarcomas n=14 and serous adenocarcinomas n=12) and 45 endometrial tumors from unexposed breast cancer patients
Project description:Full title: comparison of the genomic (arrayCGH) profiles of endometrial cancer with and without prior prolonged tamoxifen treatment for primary breast cancer Purpose: Tamoxifen has been a very effective treatment for breast cancer for several decades, however, at the same time increases the risk of endometrial cancer, especially after prolonged exposure. In addition, tamoxifen has been associated with a higher proportion of unfavorable uterine tumor subtypes (carcinosarcomas and serous adenocarcinomas) with worse survival. We investigated whether endometrial tumors, which developed after prolonged tamoxifen treatment for breast cancer, are genetically different from endometrial tumors without preceding tamoxifen exposure. Experimental design: Array CGH was used on archival formalin-fixed paraffin embedded (FFPE) endometrial tumors to determine genomic aberrations. We compared the genomic profiles of 52 endometrial tumors from breast cancer patients after long-term (>=2 years) tamoxifen use (endometrioid adenocarcinomas n=26, carcinosarcomas n=14 and serous adenocarcinomas n=12) with endometrial tumors from unexposed breast cancer patients (n=45). Genomic profiles were correlated with tamoxifen exposure, tumor subtypes and histopathological characteristics of the endometrial tumors. Results: The common uterine corpus cancers of the endometrioid subtype show few genomic aberrations. Tumors with many genomic aberrations were in general ER-negative. In contrast, carcinosarcomas and serous adenocarcinomas showed many aberrations, however they were indistinguishable from each other. Tumors that developed after prolonged tamoxifen use did not show more or different aberrations than unexposed tumors. This was true for all tumor subtypes. Conclusion: Endometrial carcinomas that develop after prolonged tamoxifen use can not be distinguished from non-users on basis of their tumor genomic profile.
Project description:Tamoxifen, a small molecule inhibitor that binds the Estrogen Receptor alpha (ERα), blocks breast cancer progression while increasing the risk for endometrial cancer. In this study, we assessed genome-wide ERα-chromatin interactions in surgical specimens of endometrial tumors from patients who were previously treated for breast cancer with tamoxifen, and endometrial tumors from patients who were treated without tamoxifen. We compared ERα and signal at differential ERα sites in endometrial tumors of nine patients who received tamoxifen with endometrial tumors with six patients who never used tamoxifen. In addition, we performed H3K27ac (a marker for activity) ChIPs on the above mentioned endometrial tumors, and assed this signal at differential ERα sites. Compared to endometrial tumors of non-users, tamoxifen-associated endometrial tumors exposed higher H3K27ac intensities at ERα sites that are enriched in tamoxifen-associated endometrial tumors. Four tamoxifen-associated endometrial tumors that we used in our analysis have been previously published as Tumor A, B, D, and E in GSE81213.
Project description:Tamoxifen, a small molecule inhibitor that binds the Estrogen Receptor alpha (ERα), blocks breast cancer progression while increasing the risk for endometrial cancer. In this study, we assessed genome-wide ERα-chromatin interactions in surgical specimens of endometrial tumors from patients who were previously treated for breast cancer with tamoxifen, and endometrial tumors from patients who were treated without tamoxifen. We compared ERα and signal at differential ERα sites in endometrial tumors of nine patients who received tamoxifen with endometrial tumors with six patients who never used tamoxifen. In addition, we performed H3K27ac (a marker for activity) ChIPs on the above mentioned endometrial tumors, and assed this signal at differential ERα sites. Compared to endometrial tumors of non-users, tamoxifen-associated endometrial tumors exposed higher H3K27ac intensities at ERα sites that are enriched in tamoxifen-associated endometrial tumors. Four tamoxifen-associated endometrial tumors that we used in our analysis have been previously published as Tumor A, B, D, and E in GSE81213.
Project description:A specific form of endometrial cancer (EC) can develop in breast cancer patients previously treated with tamoxifen (ET), an antagonist of estrogen receptor (ER) α that inhibits proliferation of ER positive breast cancer. ET tumors have a different phenotype than endometrial tumors which typically develop de novo without previous exposure to tamoxifen (EN). Here we aimed to identify specific protein markers that could serve as specific molecular targets in either phenotype. A set of total 45 formalin-fixed paraffin-embedded (FFPE) endometrial tumor tissue and adjacent myometrial tissue samples were analyzed using LC-MS/MS in SWATH-MS mode. We found that calcyphosin (CAPS) levels were elevated in EN tumors compared to ET tumors. The higher CAPS level in EC tissue invading to myometrium support its relationship to EC aggressiveness. Further, stathmin (STMN1) levels were found significantly elevated in ET vs. EN tumors and significantly associated with patient survival. This finding connects elevated levels of this cell cycle regulating, proliferation-associated protein with tamoxifen exposure. In a summary, using SWATH-MS we show that CAPS and STMN1 should be recognized as clinicopathologically different EC markers of which STMN1 is specifically connected with a previous tamoxifen exposition.
Project description:Tamoxifen, which is used to treat breast cancer, increases the risks of endometrial cancer. In this study, we performed a genome-wide assessment of ERα-chromatin interactions in surgical specimens obtained from patients with tamoxifen-associated endometrial cancer. ERα was found at active enhancers in endometrial cancer cells as marked by the presence of RNA polymerase II and the histone marker H3K27Ac. Our results define conserved sites for genomic interplay between FOXA1 and ERα in breast cancer and tamoxifen-associated endometrial cancer.
Project description:Estrogen receptor alpha (ESR1) mutations have been identified in hormone therapy resistant breast cancer and primary endometrial cancer. Analyses in breast cancer suggests that mutant ESR1 exhibits estrogen independent activity. In endometrial cancer, ESR1 mutations are associated with worse outcomes and less obesity, however experimental investigation of these mutations has not been performed. Using a unique CRISPR/Cas9 strategy, we introduced the D538G mutation, a common endometrial cancer mutation that alters the ligand binding domain of ESR1, while epitope tagging the endogenous locus. We discovered estrogen-independent mutant ESR1 genomic binding that is significantly altered from wildtype ESR1. The D538G mutation impacted expression, including a large set of non-estrogen regulated genes, and chromatin accessibility, with most affected loci bound by mutant ESR1. Mutant ESR1 is unique from constitutive ESR1 activity as mutant-specific changes are not recapitulated with prolonged estrogen exposure. Overall, D538G mutant ESR1 confers estrogen-independent activity while causing additional regulatory changes in endometrial cancer cells that are distinct from breast cancer cells.
Project description:Estrogen receptor alpha (ESR1) mutations have been identified in hormone therapy resistant breast cancer and primary endometrial cancer. Analyses in breast cancer suggests that mutant ESR1 exhibits estrogen independent activity. In endometrial cancer, ESR1 mutations are associated with worse outcomes and less obesity, however experimental investigation of these mutations has not been performed. Using a unique CRISPR/Cas9 strategy, we introduced the D538G mutation, a common endometrial cancer mutation that alters the ligand binding domain of ESR1, while epitope tagging the endogenous locus. We discovered estrogen-independent mutant ESR1 genomic binding that is significantly altered from wildtype ESR1. The D538G mutation impacted expression, including a large set of non-estrogen regulated genes, and chromatin accessibility, with most affected loci bound by mutant ESR1. Mutant ESR1 is unique from constitutive ESR1 activity as mutant-specific changes are not recapitulated with prolonged estrogen exposure. Overall, D538G mutant ESR1 confers estrogen-independent activity while causing additional regulatory changes in endometrial cancer cells that are distinct from breast cancer cells.
Project description:Estrogen receptor alpha (ESR1) mutations have been identified in hormone therapy resistant breast cancer and primary endometrial cancer. Analyses in breast cancer suggests that mutant ESR1 exhibits estrogen independent activity. In endometrial cancer, ESR1 mutations are associated with worse outcomes and less obesity, however experimental investigation of these mutations has not been performed. Using a unique CRISPR/Cas9 strategy, we introduced the D538G mutation, a common endometrial cancer mutation that alters the ligand binding domain of ESR1, while epitope tagging the endogenous locus. We discovered estrogen-independent mutant ESR1 genomic binding that is significantly altered from wildtype ESR1. The D538G mutation impacted expression, including a large set of non-estrogen regulated genes, and chromatin accessibility, with most affected loci bound by mutant ESR1. Mutant ESR1 is unique from constitutive ESR1 activity as mutant-specific changes are not recapitulated with prolonged estrogen exposure. Overall, D538G mutant ESR1 confers estrogen-independent activity while causing additional regulatory changes in endometrial cancer cells that are distinct from breast cancer cells.
Project description:An increased incidence of endometrial cancer has been described for patients that have received tamoxifen to treat breast cancer. Using samples from endometrial tumors, isolated from surgivcal specimens of patients who previously received tamoxifen treatment for breast cancer, we aimed to identify whether there are specific somatic mutations enriched in this population, relative to endometrial tumors from the general population. For this, WES was performed on matched endometrial tumors and healthy tissue (n=21).