Verena Kirn

GDM Alters Expression of Placental Estrogen Receptor α in a Cell Type and Gender-Specific Manner

Objective: The nuclear receptor estrogen receptor α (ERα) is one of the key players in energy balance, insulin resistance, and trophoblast differentiation. We tested the hypothesis that gestational diabetes mellitus (GDM) alters expression of placental ERα in a cell type-specific manner and that this regulation may involve epigenetic changes. Study Design: Expression of ERα was analyzed by immunohistochemistry using the semiquantitative immunoreactive score in 80 placentas (40 GDM/40 controls). Quantitative real-time polymerase chain reaction (PCR) measured ERα messenger RNA (mRNA) in decidual tissue. Methylation-specific PCR was performed to analyze cytosine-phosphatidyl-guanine-island methylation of the ERα promoter. Results: Expression of ERα protein is upregulated (P = .011) in GDM in extravillous trophoblasts but not in syncytiotrophoblast. Gestational diabetes mellitus downregulated ERα in decidual vessels only in pregnancies with male but not female fetuses. Furthermore, mRNA of the ERα encoding gene estrogen receptor gene 1 (ESR1) was increased (+1.77 fold) in GDM decidua when compared to controls (P = .024). In parallel, the promoter of ESR1 was methylated only in decidua of healthy control individuals but not in GDM. Conclusion: Gestational diabetes mellitus affects expression of placental ERα in a cell type-dependent way, on epigenetic level. These data link GDM with epigenetic deregulations of ERα expression and open new insights into the intrauterine programming hypothesis of GDM.

Intraoperative Boost Radiotherapy during Targeted Oncoplastic Breast Surgery: Overview and Single Center Experiences

Breast-conserving surgery followed by whole-breast irradiation is the standard local therapy for early breast cancer. The international discussion of reduced importance of wider tumor-free resection margins than “tumor not touching ink” leads to the development of five principles in targeted oncoplastic breast surgery. IORT improves local recurrence risk and diminishes toxicity since there is less irradiation of healthy tissue. Intraoperative radiotherapy (IORT) can be delivered in two settings: an IORT boost followed by a conventional regimen of external beam radiotherapy or a single IORT dose. The data from TARGIT-A and ELIOT reinforce the conviction that intraoperative radiotherapy during breast-conserving surgery is a reliable alternative to conventional postoperative fractionated irradiation, but only in a carefully selected population at low risk of local recurrence. We describe our experiences with IORT boost (50 kV energy X-rays; 20 Gy) in combination with targeted oncoplastic breast surgery in a routine clinical setting. Our experiences demonstrate the applicability and reliability of combining IORT boost with targeted oncoplastic breast surgery in breast-conserving therapy of early breast cancer.

Oncoplastic breast reconstruction after IORT

Prospective randomized clinical trials have shown that breast-conserving surgery followed by radiotherapy gives equivalent survival rates compared with mastectomy. The indications for breastconserving therapy in breast cancer are expanding. The integration of oncoplastic surgery techniques with breast-conserving segmentectomy is a new approach that allows more extensive resections and results in more cosmetic favourable outcomes. During the last years we have defined five reconstruction principles in oncoplastic breast-conserving surgery. With these five principles we were able to perform more than 95% of all immediate reconstructions of partial mastectomy defects during breast-conserving surgery, resulting in optimized local and aesthetic outcomes. The oncoplastic reconstruction principles of partial mastectomy defects during breast-conserving surgery are as follows: glandular rotation, dermoglandular rotation, tumoradapted reduction mammoplasty, thoracoepigastric flap, Latissimus dorsi flap. Usually the whole breast is percutaneously irradiated after breast-conserving surgery. Depending on different risk factors, a local boost dose is applied to the tumor bed, which leads to a further reduction of local recurrences. Recently, the concept of intraoperative radiotherapy (IORT) as boost during breast-conserving surgery has been introduced internationally. From a surgical point of view intraoperative boost radiotherapy with a mobile device generating low-energy X-rays (Intrabeam ® ) can be combined with all oncoplastic principles for reconstructing partial mastectomy defects. The advantage of an oncoplastic reconstruction after breastconserving surgery and IORT boost irradiation should be recommended to improve local outcome, to avoid seroma formation and to improve the cosmetic outcome after treatment.

Promotor analysis of ESR1 in endometrial cancer cell lines, endometrial and endometriotic tissue

PurposeThe nuclear hormone receptor estrogen receptor α (ERα) is pivotal for numerous processes in the cell. As a transcription factor, it regulates eukaryotic gene expression and affects cellular proliferation and differentiation in target tissues. Moreover, ERα is known for its influence on various gynecological diseases and carcinogenesis. Since its expression is often altered in diseased tissues and this alteration was found to be caused by hypermethylation of the ESR1 promotor region in cancer, including breast and colorectal cancer, the aim of this study is to elucidate if the expression of ERα is also regulated epigenetically in endometriosis and endometrial cancer.MethodsUsing real-time methylation-specific PCR (rt-MSP), we examined endometrial and endometriotic tissues as well as five endometrial cancer cell lines and compared the methylation status with the actual expression of ERα.ResultsThe results of our study indicate that, though its expression is altered in endometrial and endometriotic tissue, ERα is not regulated by methylation of the promotor region in endometriosis. In contrast, three of the five endometrial cancer cell lines are methylated in the promotor region of ESR1.ConclusionsThus, further investigation of the connection between ERα and endometrial cancer will be the next step.

Tamoxifen Treatment in Correlation with Increased ET-1 Levels Is Associated with the Development of Breast Cancer Metastases

Background: In breast cancer patients, a correlation between endothelin-1 (ET-1) and lymph node metastasis was found. While breast cancer with a positive ER status can be treated with Tamoxifen, several studies describe increasing Tamoxifen resistance in patients. We analyzed the relationship between Tamoxifen, ET-1 overexpression, and ER leading to Tamoxifen resistance. Methods: Breast cancer cell lines were treated with Tamoxifen, ET-1, estrogen and combinations. Using qRT-PCR, immune-precipitation, Western blot, EMSA and immunohistology target gene expression and ER complex partners were investigated. Human biopsies and mastectomy specimens were immunohistologically studied for Vimentin 3, and ERβ. Results: Breast cancer cells stimulated with a combination of Tamoxifen and ET-1 downregulate ERα, while upregulating intracellular ET-1, and ERβ. Immunoprecipation of nuclear extracts with ET-1, ERα or ERβ agarose conjugated antibodies reveals a complex formation change replacing ERα by ERβ once Tamoxifen forms a complex with ET-1. ERβand ET-1 migrate into the nucleus. ET-1 stimulation upregulates metastases promoting target genes (IL-6, Wnt11), including a novel one, Vimentin 3. Tissue analyses show Vim3 and ERβ expression in metastases of ERα positive breast cancer, and in ERα negative biopsies/mastectomy specimens. Conclusion: We are the first to describe a complex consisting of Tamoxifen, ERβ and ET-1, whose nuclear transmigration causes an overexpression of target genes. This mechanism may explain Tamoxifen resistance. Future pathologic analyses should include estrogen beta receptor status as well as the ET-1 expression. This concept presents a new treatment approach for individualized medicine in breast cancer patients with increased ET-1 levels.

Correction to: Promotor analysis of ESR1 in endometrial cancer cell lines, endometrial and endometriotic tissue

In the original publication of the article, the name of first author was misspelled. The correct name has been copied below:

Factors Predictive of Sentinel Lymph Node Involvement in Primary Breast Cancer

Background/Aim: Sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) for axillary staging in patients with early-stage breast cancer. The need for therapeutic ALND is the subject of ongoing debate especially after the publication of the ACOSOG Z0011 trial. In a retrospective trial with univariate and multivariate analyses, factors predictive of sentinel lymph node involvement should be analyzed in order to define tumor characteristics of breast cancer patients, where SLNB should not be spared to receive important indicators for adjuvant treatment decisions (e.g. thoracic wall irradiation after mastectomy with or without reconstruction). Patients and Methods: Between 2006 and 2010, 1,360 patients with primary breast cancer underwent SLNB with/without ALND with evaluation of tumor localization, multicentricity and multifocality, histological subtype, tumor size, grading, lymphovascular invasion (LVI), and estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 status. These characteristics were retrospectively analyzed in univariate and multivariate logistic regression models to define significant predictive factors for sentinel lymph node involvement. The multivariate analysis demonstrated that tumor size and LVI (p<0.001) were independent predictive factors for metastatic sentinel lymph node involvement in patients with early-stage breast cancer. Conclusion: Because of the increased risk for metastatic involvement of axillary sentinel nodes in cases with larger breast cancer or diagnosis of LVI, patients with these breast cancer characteristics should not be spared from SLNB in a clinically node-negative situation in order to avoid false-negative results with a high potential for wrong indication of primary breast reconstruction or wrong non-indication of necessary post-mastectomy radiation therapy. The prognostic impact of avoidance of axillary staging with SLNB is analyzed in the ongoing prospective INSEMA trial.