title: ERα and ERβ expression in correlation with Ki-67, Bcl-2 and Bak in primary tumors and lymph node metastases of breast cancer: The effect of pre-operative chemotherapy.
abstract: This study aimed to assess the pre-operative chemotherapy impact on the relationship between estrogen receptor (ER) expression and markers of proliferation and apoptosis in primary and metastatic breast cancer. Immunohistochemical examinations were conducted on surgically removed ductal invasive breast cancers and their lymph node metastases in 135 patients. A total of 64 patients from this group underwent pre-operative chemotherapy and in 71 cases the surgery was performed without primary chemotherapy. A negative correlation between ERα and Ki-67 was found in primary tumors and lymph node metastases. A positive correlation was observed between ERα and Bcl-2. A positive correlation was also noted between ERβ and Bak, suggesting that the two ERs were involved in the regulation of proteins responsible for the control of the apoptotic process. Assessment of the expression of the proteins conducted separately in primary tumors and lymph node metastases did not reveal a significant effect of pre-operative chemotherapy on the correlations of ERs with Ki-67, Bcl-2 and Bak. However, the analysis of the correlations between the receptor expression in primary tumors and Ki-67, Bcl-2 and Bak in lymph node metastases showed a statistically significant impact of pre-operative chemotherapy on the correlations of ERα and Bcl-2 with ERβ and Bak, confirming involvement of the two ERs in the regulation of apoptosis during breast carcinogenesis.
authors.affiliation: Department of Pathology, Maria Sklodowska-Curie Memorial Bialystok Oncology Center, 15-027 Bialystok.
authors.forename: Luiza
authors.initials: L
authors.lastname: Kanczuga-Koda
authors.forename: Mariusz
authors.initials: M
authors.lastname: Koda
authors.forename: Jakub
authors.initials: J
authors.lastname: Tomaszewski
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Jarzabek
authors.forename: Joanna
authors.initials: J
authors.lastname: Lotowska
authors.forename: Marek
authors.initials: M
authors.lastname: Baltaziak
authors.forename: Urszula
authors.initials: U
authors.lastname: Sulkowska
authors.forename: Maria
authors.initials: M
authors.lastname: Sobaniec-Lotowska
authors.forename: Stanisław
authors.initials: S
authors.lastname: Sulkowski