{"id":{"repo_id":"aachen","oai_identifier":"oai:publications.rwth-aachen.de:63421"},"canonical_url":"https://search.dev.ndltd.org/etd/aachen/oai:publications.rwth-aachen.de:63421","repository":{"repo_id":"aachen","name":"RWTH Aachen University","base_url":"https://publications.rwth-aachen.de/oai2d"},"display":{"title":"Hormoneller Einfluss und Effekte des HDAC-Inhibitors TSA in der T-47D- und der MCF-7-Brustkrebszelllinie","abstract":"INTRODUCTION: In Germany, breast cancer is one of the most common causes of death in the field of cancerous disease. The progression of breast cancer is highly influenced by the steroid hormones estrogen and progesterone. In addition, these tumours show variances on the epigenetic level, like gene-specific changes of the histone acetylase and histone deacetylase. The use of histone deacetylase inhibitors (HDACi), like trichostatin A (TSA), in in vitro studies of the clinical phase I and II led to an inhibition of cell growth and stimulated the differentiation of tumour cells. HDACs, especially those HDACs which belong to class I HDACs are part of the transcription conning steroid receptor complexes. Because of this the interaction between the steroids estrogen (E2) and medroxyprogesterone acetate (MPA) and the HDACi TSA was tested in this study.EXPERIMENTAL SET-UP: The mRNA and protein expression of eight different factors were examined in this dissertation. In the first test run, breast cancer cells were substituted with a) E2, b) the combination of E2 + MPA and c) no steroids. The second part of the test run consisted of a) E2+TSA, b) the combination of E2+MPA+TSA and c) only TSA. All tests lasted up to 96 hours. Independently from these test runs experiments with different doses of TSA from 0.2µM/l TSA to 2.0µM/lTSA and a time-experiment with a standard dose of 0.75µM/l TSA over 72 hours were conducted.The eight factors are: 1. histone deacetylase -1, -2 and -3, all three part of the class I HDACs, 2. estrogen receptor alpha (ER alpha), 3. two differentiation markers, Na+-K+- ATPase and zinc alpha 2-glycoprotein (ZAG), 4. clusterin (CLU) and the Kruppel-like factor 4 (KLF 4), both under regulation of estrogen and progesterone.RESULTS: The results of increasing the TSA dose show that a dose higher then 0.5µM/l TSA leads to an explicit inhibition of cell growth and induction of apoptosis which can be explained by a cytotoxic effect of high TSA doses. This TSA concentration also causes a suppression of the protein expression of HDAC-1, -2 and -3 and the ERalpha which can also be explained by the cytotoxic effect. However, a concentration of 0.2µM/l TSA interacts with the protein and mRNA expression on a very low level only. So this was used as the dose in most of the experiments. The differentiation marker Na+-K+- ATPase and the ZAG show under substitution of the steroid hormone MPA an increasing expression. This effect was even stronger in the T47 D cell line than in the MCF 7 cell line.The combination of E2+MPA leads to a suppression of the ERalpha expression compared to E2 alone. The dose of 0.2µM/l TSA has no effect on the expression of the factors mentioned above except Clusterin. In this study a regulation of Clusterin under MPA und TSA in T47 D cells is shown for the first time. The combination of E2+MPA leads to a significant suppression of the CLU mRNA expression. The supplemental addition of 0.2µM/l TSA abrogates the steroid effect. In the MCF 7 cells neither with MPA nor with 0.2µM/l TSA a regulation of CLU could be observed. Only a higher dose of TSA like 0.5µM/l and 0.75µM/l increased the CLU expression independently from the hormone treatment.CONCLUSION: There are two main results of the different experiments: On the one hand higher doses of TSA have a cytotoxic effect on cells. On the other hand there are obvious differences between the regulation of genes in the T47 D and MCF 7 cells. This is very important to know for a specific medical treatment in tumour therapies. Beside this the treatment with MPA seems to play an important role in breast cancer therapy, because different genes show under substitution of MPA a regulation on the mRNA and protein level. For example, the down regulation of the ERalpha after adding MPA can be discussed as an anti-estrogenic effect. Focused on the two differentiation markers the increased expression after substitution of MPA can be a very interesting effect for a specific therapy in progesterone sensitive breast cancers. The gestagen treatment could lead to a higher differentiation and lower malignancy of the cancer cells. The role of clusterin and the opposite effects of MPA and TSA in T47 D cells must be investigated more specifically. Right now two isoforms of clusterin are known. One is called pro-apoptotic because it is expressed during apoptosis, the other anti-apoptotic because it is increased during cell cycle progression. The effects of a specific therapy and the prognosis of breast cancer considering the CLU expression seem to depend on which of the two isoforms is under MPA and/or TSA regulation.","abstract_html":"INTRODUCTION: In Germany, breast cancer is one of the most common causes of death in the field of cancerous disease. The progression of breast cancer is highly influenced by the steroid hormones estrogen and progesterone. In addition, these tumours show variances on the epigenetic level, like gene-specific changes of the histone acetylase and histone deacetylase. The use of histone deacetylase inhibitors (HDACi), like trichostatin A (TSA), in in vitro studies of the clinical phase I and II led to an inhibition of cell growth and stimulated the differentiation of tumour cells. HDACs, especially those HDACs which belong to class I HDACs are part of the transcription conning steroid receptor complexes. Because of this the interaction between the steroids estrogen (E2) and medroxyprogesterone acetate (MPA) and the HDACi TSA was tested in this study.EXPERIMENTAL SET-UP: The mRNA and protein expression of eight different factors were examined in this dissertation. In the first test run, breast cancer cells were substituted with a) E2, b) the combination of E2 + MPA and c) no steroids. The second part of the test run consisted of a) E2+TSA, b) the combination of E2+MPA+TSA and c) only TSA. All tests lasted up to 96 hours. Independently from these test runs experiments with different doses of TSA from 0.2µM/l TSA to 2.0µM/lTSA and a time-experiment with a standard dose of 0.75µM/l TSA over 72 hours were conducted.The eight factors are: 1. histone deacetylase -1, -2 and -3, all three part of the class I HDACs, 2. estrogen receptor alpha (ER alpha), 3. two differentiation markers, Na+-K+- ATPase and zinc alpha 2-glycoprotein (ZAG), 4. clusterin (CLU) and the Kruppel-like factor 4 (KLF 4), both under regulation of estrogen and progesterone.RESULTS: The results of increasing the TSA dose show that a dose higher then 0.5µM/l TSA leads to an explicit inhibition of cell growth and induction of apoptosis which can be explained by a cytotoxic effect of high TSA doses. This TSA concentration also causes a suppression of the protein expression of HDAC-1, -2 and -3 and the ERalpha which can also be explained by the cytotoxic effect. However, a concentration of 0.2µM/l TSA interacts with the protein and mRNA expression on a very low level only. So this was used as the dose in most of the experiments. The differentiation marker Na+-K+- ATPase and the ZAG show under substitution of the steroid hormone MPA an increasing expression. This effect was even stronger in the T47 D cell line than in the MCF 7 cell line.The combination of E2+MPA leads to a suppression of the ERalpha expression compared to E2 alone. The dose of 0.2µM/l TSA has no effect on the expression of the factors mentioned above except Clusterin. In this study a regulation of Clusterin under MPA und TSA in T47 D cells is shown for the first time. The combination of E2+MPA leads to a significant suppression of the CLU mRNA expression. The supplemental addition of 0.2µM/l TSA abrogates the steroid effect. In the MCF 7 cells neither with MPA nor with 0.2µM/l TSA a regulation of CLU could be observed. Only a higher dose of TSA like 0.5µM/l and 0.75µM/l increased the CLU expression independently from the hormone treatment.CONCLUSION: There are two main results of the different experiments: On the one hand higher doses of TSA have a cytotoxic effect on cells. On the other hand there are obvious differences between the regulation of genes in the T47 D and MCF 7 cells. This is very important to know for a specific medical treatment in tumour therapies. Beside this the treatment with MPA seems to play an important role in breast cancer therapy, because different genes show under substitution of MPA a regulation on the mRNA and protein level. For example, the down regulation of the ERalpha after adding MPA can be discussed as an anti-estrogenic effect. Focused on the two differentiation markers the increased expression after substitution of MPA can be a very interesting effect for a specific therapy in progesterone sensitive breast cancers. The gestagen treatment could lead to a higher differentiation and lower malignancy of the cancer cells. The role of clusterin and the opposite effects of MPA and TSA in T47 D cells must be investigated more specifically. Right now two isoforms of clusterin are known. One is called pro-apoptotic because it is expressed during apoptosis, the other anti-apoptotic because it is increased during cell cycle progression. The effects of a specific therapy and the prognosis of breast cancer considering the CLU expression seem to depend on which of the two isoforms is under MPA and/or TSA regulation.","abstract_has_math":false,"creators":["Fiedor, Annette Stephanie"],"institution":"Publikationsserver der RWTH Aachen University","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":["Krusche, Claudia Astrid"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009","date_published":"2009","updated_at":"2026-07-30T19:43:35Z","subjects":["info:eu-repo/classification/ddc/610","Brustkrebs","Histon-Deacetylase","Östrogene","Medizin","T47D","Trichostatin A","MCF7","steroid hormones","breast cancer"],"languages":["ger"],"rights":["info:eu-repo/semantics/openAccess"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124852%22"],"render_values":[{"text":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124852%22","href":"https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124852%22","code":true}]}]},"links":{"outbound_url":"https://publications.rwth-aachen.de/record/63421","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Krusche, Claudia Astrid"]},{"key":"dc:creator","label":"Author","values":["Fiedor, Annette Stephanie"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:coverage","label":"Dc Coverage","values":["DE"]},{"key":"dc:date","label":"Dc Date","values":["2009"]},{"key":"dc:publisher","label":"Institution","values":["Publikationsserver der RWTH Aachen University"]},{"key":"dc:relation","label":"Dc Relation","values":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-29851"]},{"key":"dc:type","label":"Dc Type","values":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["info:eu-repo/classification/ddc/610","Brustkrebs","Histon-Deacetylase","Östrogene","Medizin","T47D","Trichostatin A","MCF7","steroid hormones","breast cancer"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["ger"]},{"key":"dc:rights","label":"Dc Rights","values":["info:eu-repo/semantics/openAccess"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://publications.rwth-aachen.de/record/63421","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124852%22"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["INTRODUCTION: In Germany, breast cancer is one of the most common causes of death in the field of cancerous disease. The progression of breast cancer is highly influenced by the steroid hormones estrogen and progesterone. In addition, these tumours show variances on the epigenetic level, like gene-specific changes of the histone acetylase and histone deacetylase. The use of histone deacetylase inhibitors (HDACi), like trichostatin A (TSA), in in vitro studies of the clinical phase I and II led to an inhibition of cell growth and stimulated the differentiation of tumour cells. HDACs, especially those HDACs which belong to class I HDACs are part of the transcription conning steroid receptor complexes. Because of this the interaction between the steroids estrogen (E2) and medroxyprogesterone acetate (MPA) and the HDACi TSA was tested in this study.EXPERIMENTAL SET-UP: The mRNA and protein expression of eight different factors were examined in this dissertation. In the first test run, breast cancer cells were substituted with a) E2, b) the combination of E2 + MPA and c) no steroids. The second part of the test run consisted of a) E2+TSA, b) the combination of E2+MPA+TSA and c) only TSA. All tests lasted up to 96 hours. Independently from these test runs experiments with different doses of TSA from 0.2µM/l TSA to 2.0µM/lTSA and a time-experiment with a standard dose of 0.75µM/l TSA over 72 hours were conducted.The eight factors are: 1. histone deacetylase -1, -2 and -3, all three part of the class I HDACs, 2. estrogen receptor alpha (ER alpha), 3. two differentiation markers, Na+-K+- ATPase and zinc alpha 2-glycoprotein (ZAG), 4. clusterin (CLU) and the Kruppel-like factor 4 (KLF 4), both under regulation of estrogen and progesterone.RESULTS: The results of increasing the TSA dose show that a dose higher then 0.5µM/l TSA leads to an explicit inhibition of cell growth and induction of apoptosis which can be explained by a cytotoxic effect of high TSA doses. This TSA concentration also causes a suppression of the protein expression of HDAC-1, -2 and -3 and the ERalpha which can also be explained by the cytotoxic effect. However, a concentration of 0.2µM/l TSA interacts with the protein and mRNA expression on a very low level only. So this was used as the dose in most of the experiments. The differentiation marker Na+-K+- ATPase and the ZAG show under substitution of the steroid hormone MPA an increasing expression. This effect was even stronger in the T47 D cell line than in the MCF 7 cell line.The combination of E2+MPA leads to a suppression of the ERalpha expression compared to E2 alone. The dose of 0.2µM/l TSA has no effect on the expression of the factors mentioned above except Clusterin. In this study a regulation of Clusterin under MPA und TSA in T47 D cells is shown for the first time. The combination of E2+MPA leads to a significant suppression of the CLU mRNA expression. The supplemental addition of 0.2µM/l TSA abrogates the steroid effect. In the MCF 7 cells neither with MPA nor with 0.2µM/l TSA a regulation of CLU could be observed. Only a higher dose of TSA like 0.5µM/l and 0.75µM/l increased the CLU expression independently from the hormone treatment.CONCLUSION: There are two main results of the different experiments: On the one hand higher doses of TSA have a cytotoxic effect on cells. On the other hand there are obvious differences between the regulation of genes in the T47 D and MCF 7 cells. This is very important to know for a specific medical treatment in tumour therapies. Beside this the treatment with MPA seems to play an important role in breast cancer therapy, because different genes show under substitution of MPA a regulation on the mRNA and protein level. For example, the down regulation of the ERalpha after adding MPA can be discussed as an anti-estrogenic effect. Focused on the two differentiation markers the increased expression after substitution of MPA can be a very interesting effect for a specific therapy in progesterone sensitive breast cancers. The gestagen treatment could lead to a higher differentiation and lower malignancy of the cancer cells. The role of clusterin and the opposite effects of MPA and TSA in T47 D cells must be investigated more specifically. Right now two isoforms of clusterin are known. One is called pro-apoptotic because it is expressed during apoptosis, the other anti-apoptotic because it is increased during cell cycle progression. The effects of a specific therapy and the prognosis of breast cancer considering the CLU expression seem to depend on which of the two isoforms is under MPA and/or TSA regulation."]},{"key":"dc:source","label":"Dc Source","values":["Aachen : Publikationsserver der RWTH Aachen University 85 S. : Ill., graph. Darst. (2009). = Aachen, Techn. Hochsch., Diss., 2009"]},{"key":"dc:title","label":"Title","values":["Hormoneller Einfluss und Effekte des HDAC-Inhibitors TSA in der T-47D- und der MCF-7-Brustkrebszelllinie"]}]}],"canonical_facts":{"dc:contributor":["Krusche, Claudia Astrid"],"dc:coverage":["DE"],"dc:creator":["Fiedor, Annette Stephanie"],"dc:date":["2009"],"dc:description":["INTRODUCTION: In Germany, breast cancer is one of the most common causes of death in the field of cancerous disease. The progression of breast cancer is highly influenced by the steroid hormones estrogen and progesterone. In addition, these tumours show variances on the epigenetic level, like gene-specific changes of the histone acetylase and histone deacetylase. The use of histone deacetylase inhibitors (HDACi), like trichostatin A (TSA), in in vitro studies of the clinical phase I and II led to an inhibition of cell growth and stimulated the differentiation of tumour cells. HDACs, especially those HDACs which belong to class I HDACs are part of the transcription conning steroid receptor complexes. Because of this the interaction between the steroids estrogen (E2) and medroxyprogesterone acetate (MPA) and the HDACi TSA was tested in this study.EXPERIMENTAL SET-UP: The mRNA and protein expression of eight different factors were examined in this dissertation. In the first test run, breast cancer cells were substituted with a) E2, b) the combination of E2 + MPA and c) no steroids. The second part of the test run consisted of a) E2+TSA, b) the combination of E2+MPA+TSA and c) only TSA. All tests lasted up to 96 hours. Independently from these test runs experiments with different doses of TSA from 0.2µM/l TSA to 2.0µM/lTSA and a time-experiment with a standard dose of 0.75µM/l TSA over 72 hours were conducted.The eight factors are: 1. histone deacetylase -1, -2 and -3, all three part of the class I HDACs, 2. estrogen receptor alpha (ER alpha), 3. two differentiation markers, Na+-K+- ATPase and zinc alpha 2-glycoprotein (ZAG), 4. clusterin (CLU) and the Kruppel-like factor 4 (KLF 4), both under regulation of estrogen and progesterone.RESULTS: The results of increasing the TSA dose show that a dose higher then 0.5µM/l TSA leads to an explicit inhibition of cell growth and induction of apoptosis which can be explained by a cytotoxic effect of high TSA doses. This TSA concentration also causes a suppression of the protein expression of HDAC-1, -2 and -3 and the ERalpha which can also be explained by the cytotoxic effect. However, a concentration of 0.2µM/l TSA interacts with the protein and mRNA expression on a very low level only. So this was used as the dose in most of the experiments. The differentiation marker Na+-K+- ATPase and the ZAG show under substitution of the steroid hormone MPA an increasing expression. This effect was even stronger in the T47 D cell line than in the MCF 7 cell line.The combination of E2+MPA leads to a suppression of the ERalpha expression compared to E2 alone. The dose of 0.2µM/l TSA has no effect on the expression of the factors mentioned above except Clusterin. In this study a regulation of Clusterin under MPA und TSA in T47 D cells is shown for the first time. The combination of E2+MPA leads to a significant suppression of the CLU mRNA expression. The supplemental addition of 0.2µM/l TSA abrogates the steroid effect. In the MCF 7 cells neither with MPA nor with 0.2µM/l TSA a regulation of CLU could be observed. Only a higher dose of TSA like 0.5µM/l and 0.75µM/l increased the CLU expression independently from the hormone treatment.CONCLUSION: There are two main results of the different experiments: On the one hand higher doses of TSA have a cytotoxic effect on cells. On the other hand there are obvious differences between the regulation of genes in the T47 D and MCF 7 cells. This is very important to know for a specific medical treatment in tumour therapies. Beside this the treatment with MPA seems to play an important role in breast cancer therapy, because different genes show under substitution of MPA a regulation on the mRNA and protein level. For example, the down regulation of the ERalpha after adding MPA can be discussed as an anti-estrogenic effect. Focused on the two differentiation markers the increased expression after substitution of MPA can be a very interesting effect for a specific therapy in progesterone sensitive breast cancers. The gestagen treatment could lead to a higher differentiation and lower malignancy of the cancer cells. The role of clusterin and the opposite effects of MPA and TSA in T47 D cells must be investigated more specifically. Right now two isoforms of clusterin are known. One is called pro-apoptotic because it is expressed during apoptosis, the other anti-apoptotic because it is increased during cell cycle progression. The effects of a specific therapy and the prognosis of breast cancer considering the CLU expression seem to depend on which of the two isoforms is under MPA and/or TSA regulation."],"dc:identifier":["https://publications.rwth-aachen.de/record/63421","https://publications.rwth-aachen.de/search?p=id:%22RWTH-CONV-124852%22"],"dc:language":["ger"],"dc:publisher":["Publikationsserver der RWTH Aachen University"],"dc:relation":["info:eu-repo/semantics/altIdentifier/urn/urn:nbn:de:hbz:82-opus-29851"],"dc:rights":["info:eu-repo/semantics/openAccess"],"dc:source":["Aachen : Publikationsserver der RWTH Aachen University 85 S. : Ill., graph. Darst. (2009). = Aachen, Techn. Hochsch., Diss., 2009"],"dc:subject":["info:eu-repo/classification/ddc/610","Brustkrebs","Histon-Deacetylase","Östrogene","Medizin","T47D","Trichostatin A","MCF7","steroid hormones","breast cancer"],"dc:title":["Hormoneller Einfluss und Effekte des HDAC-Inhibitors TSA in der T-47D- und der MCF-7-Brustkrebszelllinie"],"dc:type":["info:eu-repo/semantics/doctoralThesis","info:eu-repo/semantics/publishedVersion"]},"updated_at":"2026-07-30T19:43:35Z"}