Homogeneous datasets of triple negative breast cancers enable the identification of novel prognostic and predictive signatures

Background

Current prognostic gene signatures for breast cancer mainly reflect proliferation status and have limited value in triple-negative (TNBC) cancers. The identification of prognostic signatures from TNBC cohorts was limited in the past due to small sample sizes.

Methodology/Principal Findings

We assembled all currently publically available TNBC gene expression datasets generated on Affymetrix gene chips. Inter-laboratory variation was minimized by filtering methods for both samples and genes. Supervised analysis was performed to identify prognostic signatures from 394 cases which were subsequently tested on an independent validation cohort (n = 261 cases).

Conclusions/Significance

Using two distinct false discovery rate thresholds, 25% and <3.5%, a larger (n = 264 probesets) and a smaller (n = 26 probesets) prognostic gene sets were identified and used as prognostic predictors. Most of these genes were positively associated with poor prognosis and correlated to metagenes for inflammation and angiogenesis. No correlation to other previously published prognostic signatures (recurrence score, genomic grade index, 70-gene signature, wound response signature, 7-gene immune response module, stroma derived prognostic predictor, and a medullary like signature) was observed. In multivariate analyses in the validation cohort the two signatures showed hazard ratios of 4.03 (95% confidence interval [CI] 1.71–9.48; P = 0.001) and 4.08 (95% CI 1.79–9.28; P = 0.001), respectively. The 10-year event-free survival was 70% for the good risk and 20% for the high risk group. The 26-gene signatures had modest predictive value (AUC = 0.588) to predict response to neoadjuvant chemotherapy, however, the combination of a B-cell metagene with the prognostic signatures increased its response predictive value. We identified a 264-gene prognostic signature for TNBC which is unrelated to previously known prognostic signatures.

P3-01-12: Prognostic Impact of RANK, RANKL and OPG Gene Expression in ER Positive Primary Breast Cancer

Background

The cell surface receptor RANK (receptor activator of NFκB), its ligand (RANKL) and the decoy receptor of RANKL osteoprotegerin (OPG) play an important functional role in bone physiology and in bone metastasis by regulating osteoclasts. Just recently it was shown that tumor-infiltrating lymphocytes can stimulate breast cancer metastases through RANK-RANKL signalling.

Material and methods: We analyzed gene expression of RANK, RANKL and OPG in a combined Affymetrix dataset of 307 ER positive breast cancers from our institutions which were either untreated of treated with chemotherapy. Kaplan Meier analysis of disease free survival and Cox regression analysis was applied to examine the prognostic value of the different markers.

Results: We observed no significant difference in survival when samples were analyzed according to either RANK or RANKL mRNA expression. In contrast when samples were stratified in quartiles of OPG expression a positive linear relationship of survival with the expression of OPG was observed. Moreover since OPG demonstrated a bimodal type of expression a cutoff value can be derived from the expression data. Using this cutoff value a hazard ration of 2.14 (95% CI 1.27−3.61; P=0.004 for low OPG expression was detected. OPG expression correlated with lower proportion of grade 3 tumors (15.7% vs 27%; P=0.022) and a higher proportion of PgR positive samples (86.2% vs 71.4%; P=0.002). No significant differences were observed for lymph node status, age, tumor size and HER2 status. In multivariate analysis only lymph node status remained significant while OPG, Ki67, age, grade, and PgR only displayed a trend towards significance.

Conclusion: Expression of osteoprotegerin seems to correlate with good prognosis in ER postive breast cancer. These data are in line with in vitro studies demonstration that OPG inhibits RANKL induced migration of tumor cells.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-01-12.

A clinically relevant gene signature in triple negative and basal-like breast cancer

INTRODUCTION

Current prognostic gene expression profiles for breast cancer mainly reflect proliferation status and are most useful in ER-positive cancers. Triple negative breast cancers (TNBC) are clinically heterogeneous and prognostic markers and biology-based therapies are needed to better treat this disease.

METHODS

We assembled Affymetrix gene expression data for 579 TNBC and performed unsupervised analysis to define metagenes that distinguish molecular subsets within TNBC. We used n = 394 cases for discovery and n = 185 cases for validation. Sixteen metagenes emerged that identified basal-like, apocrine and claudin-low molecular subtypes, or reflected various non-neoplastic cell populations, including immune cells, blood, adipocytes, stroma, angiogenesis and inflammation within the cancer. The expressions of these metagenes were correlated with survival and multivariate analysis was performed, including routine clinical and pathological variables.

RESULTS

Seventy-three percent of TNBC displayed basal-like molecular subtype that correlated with high histological grade and younger age. Survival of basal-like TNBC was not different from non basal-like TNBC. High expression of immune cell metagenes was associated with good and high expression of inflammation and angiogenesis-related metagenes were associated with poor prognosis. A ratio of high B-cell and low IL-8 metagenes identified 32% of TNBC with good prognosis (hazard ratio (HR) 0.37, 95% CI 0.22 to 0.61; P < 0.001) and was the only significant predictor in multivariate analysis including routine clinicopathological variables.

CONCLUSIONS

We describe a ratio of high B-cell presence and low IL-8 activity as a powerful new prognostic marker for TNBC. Inhibition of the IL-8 pathway also represents an attractive novel therapeutic target for this disease.

SATB1 gene expression and breast cancer prognosis

Recently it has been shown that the genome organizer SATB1 plays an important role in breast cancer progression and predicts a poor prognosis. However its prognostic value compared to markers as the estrogen receptor is currently unclear. The expression levels of SATB1 mRNA from Affymetrix microarray in a cohort of 2058 breast cancer samples and its prognostic impact were analyzed. There was no significant difference in disease-free survival among ER negative cancers but instead a benefit for high SATB1 expression among ER positive tumors (p = 0.042). However, even in ER positive cancer no independent prognostic value in multivariate analysis with standard parameters was observed. Thus the use of SATB1 as target or prognostic marker for breast cancer should be viewed with caution and a possible confounding effect of the estrogen receptor status of the tumor should be taken into account when analysing new markers as SATB1.

The Luminal B Marker NHERF1 Predicts Endocrine Resistance

Background:Tumors of the luminal B subtype of ER postive breast cancer are characterized by high proliferation as compared to the luminal A subtype. The luminal B have a worse prognosis. We aimed to identify genes specifically expressed in the luminal B subtype of breast cancers and analyze the prognostic impact of these genes and their relationship to endocrine therapy.Methods:121 genes overexpressed in LumB tumors were identified in a test set of 171 Breast cancer samples and reproducibly obtained in four independent validation datasets. The scaffold protein NHERF1 was analyzed in a large scale meta-analysis of microarray datasets encompassing n=3030 breast cancer samples.Results:NHERF1 is an ER regulated gene located on chromosome 17 coding for a scaffold protein involved in growth factor signal transduction. NHERF1 expression among ER positive tumors is associated with larger tumor size, higher histolocigal grading, and HER2 expression. A prognostic value of NHERF1 was observed among ER positive tumors (univariate HR 1.49, 95% CI 1.23-1.80, P&lt;0.001) but not among ER negative samples. NHERF1 remained significant in multivariate analysis (HR 1.37, 95% CI 1.05-1.79, P=0.020) and is not a surrogate marker for high proliferation. A benefit of endocrine treatment seems to be restricted to NHERF1 negative tumors.Conclusions:Markers like NHERF1 specific for the luminal B subtype of breast cancer correlate with poor prognosis and seem to be predictive for endocrine treatment response.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3164.

Correlation of Thymidine Phosphorylase Expression and Lymphocyte Infiltration Detected by Microarray Analysis of Breast Cancer

Background:Thymidine phosphorylase (TP) expression in carcinoma cells has been described as a prognostic factor in breast cancer and a predictive factor for response to 5-FU chemotherapy in some studies. Analysis from prostate cancer reported a correlation of TP with lymphocyte infiltrates of tumors.Material and Methods:Affymetrix microarray data of n=79 normal tissue samples and n=1781 primary breast cancers were analyzed for TP mRNA expression. To study relationships of TP expression with immune cell infiltration of breast tumors we used several metagenes representing certain types of immune cells. Immunohistochemical analysis of TP protein expression using a monoclonal antibody was applied for validation studies.Results:Among normal tissues highest expression of TP mRNA was observed in cells and tissues of the immune system. The profile of TP expression displayed highest correlation with a metagene representing cells of the myeloid lineage as moncytes, macrophages and dendritic cells. Analysis of microarray data from 1781 breast cancer samples suggests that TP expression detected by this method originates mainly from infiltrating immune cells. In line with this observation TP mRNA expression correlated with a immune cell infiltration score determined by pathological inspection of the tumor. However, we also observed a correlation of TP with a metagene of interferone inducible genes which seem to be expressed by carcinoma cells. When we tried to validate these data on the protein level using immunohistochemistry TP expression was demonstrated both in carcinoma cells and stromal cells of the tumor to a varying degree.Discussion:We were able to confirm previous data from prostate cancer that TP expression is strongly correlated to the presence of an intense lymphocyte infiltrate of the tumor for breast cancer. However, microarray data of a bulk tumor sample cannot reveal the cellular origin of TP expression.Conclusion:Thus from this data it is not clear whether lymphocytes of the myeloid lineage either are the actual source of TP expression or induce its expression in carcinoma cells.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 2139.

Clinical relevance of the putative stem cell marker p63 in breast cancer

P63 is a member of the p53 family. This protein is crucial for the maintenance of a stem cell population in the human epithelium and necessary for the normal development of all epithelial tissues including mammary glands. In normal breast tissue, the p63 seems to be a specific myoepithelial cell marker. P63 expression has been described in highly aggressive ER negative basal-like breast tumors. The value of p63 expression in ER positive disease is less clear. The expression levels of p63 mRNA by Affymetrix microarray analysis in a combined cohort of 2,158 ER positive breast cancers and its prognostic and predictive impact were analyzed. Tumor samples containing large amounts of benign breast tissue, which will interfere with p63 measurement, were excluded prior to the analysis. Survival analysis revealed a better prognosis of ER positive breast cancer expressing p63 (n = 410; P < 0.036). No correlation of p63 with standard parameters was observed. In a subgroup analysis, endocrine-treated patients with high p63 expression showed a better prognosis than low p63 expression (P = 0.06; n = 186). In untreated patients, this effect was less clear (n = 148; P = 0.5). P63 is a positive prognostic factor in endocrine-treated ER positive breast cancer and might influence responsiveness to endocrine treatment. Thus, p63 could be helpful as a predictive factor for endocrine therapy.

Use of microarray analysis of differentially expressed genes in luminal B subtype of breast cancers to evaluate NHERF1 as a marker of endocrine resistance

11015

Background: In vitro and in vivo data demonstrate that the expression of estrogen receptor (ER) in breast cancer is mainly associated with low proliferation. Gene expression profiling has recently been used to identify a group of high proliferating estrogen receptor positive breast cancers (the luminal B subtype), which are associated with a prognosis that is even worse than that of high proliferating estrogen receptor negative tumors. The analysis of those tumors might provide valuable information about breast cancer biology and could be helpful for adjuvant or neoadjuvant treatment decisions.Methods and Results: We analyzed microarray data from breast cancer specimens to gain insight into genes which play a role in estrogen receptor signalling. Genes were identified showing strong expression in high proliferating ER-positive tumors but no expression in either Ki67-/ER+ or Ki67+/ER- samples. Among these genes the Na+/H+ exchanger regulatory factor NHERF1 was found. We assessed the clinical relevance of NHERF1 transcript levels using a total of 2469 breast cancers. Analysis indicates that enhanced NHERF1 expression is associated with metastatic progression and poor prognosis of breast cancer patients. We found no correlation between NHERF1 and the nodal status as well as age, but positive correlations for tumor size (P<0.001), grade (P<0.001) and erbb2 (P=0.033). Weak NHERF1 expression correlated with longer disease free survival (DFS) in grade 1 and 2 tumors, but not in grade 3 breast cancers. Since NHERF1 expression is strongly linked to the presence of ER, the predictive value for endocrine treatment was analyzed. For samples with weak or none NHERF1 expression a treatment benefit was observed (P=0.007). While untreated patients display a 10 yr DFS rate of 67.2 ± 3.8%, endocrine treatment resulted in 80.1 ± 4.0%. In contrast no differences in disease free survival were found for corresponding NHERF1 expressing breast cancers. Conclusions: Our data indicate that expression of NHERF1 defines a state of differentiation, where breast cancer cells are refractory to endocrine treatment.

No significant financial relationships to disclose.

T-cell metagene predicts a favorable prognosis in estrogen receptor-negative and HER2-positive breast cancers

INTRODUCTION

Lymphocyte infiltration (LI) is often seen in breast cancer but its importance remains controversial. A positive correlation of human epidermal growth factor receptor 2 (HER2) amplification and LI has been described, which was associated with a more favorable outcome. However, specific lymphocytes might also promote tumor progression by shifting the cytokine milieu in the tumor.

METHODS

Affymetrix HG-U133A microarray data of 1,781 primary breast cancer samples from 12 datasets were included. The correlation of immune system-related metagenes with different immune cells, clinical parameters, and survival was analyzed.

RESULTS

A large cluster of nearly 600 genes with functions in immune cells was consistently obtained in all datasets. Seven robust metagenes from this cluster can act as surrogate markers for the amount of different immune cell types in the breast cancer sample. An IgG metagene as a marker for B cells had no significant prognostic value. In contrast, a strong positive prognostic value for the T-cell surrogate marker (lymphocyte-specific kinase (LCK) metagene) was observed among all estrogen receptor (ER)-negative tumors and those ER-positive tumors with a HER2 overexpression. Moreover ER-negative tumors with high expression of both IgG and LCK metagenes seem to respond better to neoadjuvant chemotherapy.

CONCLUSIONS

Precise definitions of the specific subtypes of immune cells in the tumor can be accomplished from microarray data. These surrogate markers define subgroups of tumors with different prognosis. Importantly, all known prognostic gene signatures uniformly assign poor prognosis to all ER-negative tumors. In contrast, the LCK metagene actually separates the ER-negative group into better or worse prognosis.

Prognostic and predictive value of enzymes of the sphingolipid metabolism in breast cancer

Abstract #6014

Backround:&#x2028; Sphingolipids do not only have structural roles for the cell membrane, but also act as effector molecules and second messengers in signal transduction with links to cancer initiation, progression and treatment response. Knowledge of sphingolipid's impact on breast cancer and its prognosis is limited to in vitro data. Clinical data is rare but needed.&#x2028; Material and Methods: We analyzed gene expression of 43 proteins from the sphingolipid pathways in different subtypes of breast cancer using microarray data of 1269 tumor samples (test set n=171; validation sets n=1098). Kaplan Meier analysis of disease free survival was performed to examine the prognostic value of different markers. In addition immunohistochemistry was done to determine whether the genes of the sphingolipid rheostat are expressed in cancer or stroma cells of the tumor.&#x2028; Results: Significant relationships of several genes of the sphingolipid metabolism with clinical parameters were obtained. Sphingosine kinase 1 (SPHK1), ceramide galactosyltransferase (UGT8), and Ganglioside GD3-Synthase (ST8SIA1) displayed higher expression among ER negative tumors. In contrast, glucosylceramidesynthase (GCS), dihydroceramidesynthases (LASS4, LASS 6) and acid ceramidase (ASAH1) were higher expressed in ER positive samples. Survival analysis revealed a significant worse outcome of patients with high SPHK1 expression. LASS 6 and GCS gene expression had no prognostic impact when the estrogen receptor status was taken into account in multivariate analyses. Immunohistochemistry identified the carcinoma cells as the major source of SPHK1 expression in the tumor.&#x2028; Conclusions: These studies of a large cohort of clinical breast cancer samples reveal that sphingolipids do play a role in breast cancer. Enzymes of the sphingolipid metabolism have impact on the prognosis of breast cancer patients and targeting the sphingolipid rheostat can open new treatment options.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6014.

T cell marker metagene predicts a favourable prognosis in estrogen receptor negative and Her2 positive breast cancers

Abstract #1048

Background: Lymphocyte infiltration (LI) is often seen in breast cancer and has been suggested as a marker of host antitumor immune response but its importance remains controversial. A positive correlation of Her2 amplification/overexpression and LI has been described which was associated with a more favorable outcome. In rapidly proliferating tumors LI is a good prognostic indicator correlating with lymph node negativity, smaller tumor size, lower grade. However the impact of monocytes, B- and T-lymphocytes on prognosis are still a matter of debate.&#x2028; Material and Methods: A database of 2110 primary invasive breast cancer samples from 14 microarray datasets was established. Only Affymetrix HG-U133A microarrays were included for full comparability. Feature reduction was achieved by generating metagenes from genes with strong correlation in unsupervised clustering. The relationship of the five major metagenes with different cell types in the sample as well as differentiation programs/pathways associated with specific expression profiles was analyzed.&#x2028; Results: A large cluster of approximately 600 genes with functions in immune cells was consistently obtained in all datasets. The redundant information from several ProbeSets allowed the construction of robust metagenes which can be used as surrogate markers for the amount of different immune cell types in the breast cancer sample. However, rather complex relationships of these immunological metagenes with standard parameters of the tumors were observed. When different subgroups of tumors were analyzed for disease free survival the IgG metagene as a surrogate marker for B cells had no significant prognostic value. In contrast high expression of the T cell surrogate marker (LCK metagene) was beneficial among all subgroups of ER-negative tumors. Moreover a positive prognostic value of LCK metagene expression was also revealed for those ER-positive tumors with a Her2 overexpression. In addition a trend for a better response to neoadjuvant chemotherapy was detected for those ER negative tumors associated with lymphocyte infiltration as deduced from high expression of both IgG and LCK metagenes.&#x2028; Conclusions: Tumor associated lymphocytes could represent an anti tumor response but on the other hand they might promote tumor progression by shifting the cytokine milieu toward angiogenic factors, inflammatory cytokines and matrix metallo-proteinases. Thus it is crucial to precisely define the specific subtypes of immune cells which are associated with the tumor. Our results demonstrate that this task can be accomplished by a detailed analysis of the expression of metagenes. These surrogate markers define subgroups of tumors with different prognosis.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1048.

Differential expression of claudins in human endometrium and endometriosis

Membrane proteins of the claudin superfamily are important components of cellular tight and adherens junctions. Although their exact function remains unclear, these proteins may play a role in tissue remodeling, a process which is associated with several diseases including endometriosis. In the present work we analyzed the expression of 13 members of the claudin family in the endometrium and peritoneum by microarray analysis. Real-time polymerase chain reaction and immunohistochemistry in human endometrium and peritoneal endometriotic lesions were performed for validation of the expression of claudin-1, -3, -4, -5 and -7. Diminished expression of claudin-3, -4 and -7 in ectopic endometrium was frequently observed as indicated by all three methods. In contrast to a higher expression of claudin-5 mRNA detected in bulk biopsies of ectopic endometrium, immunohistochemistry revealed no alteration of claudin-5 protein expression in glandular cells of endometriosis samples. The downregulation of various members of the claudin family may contribute to endometrial cell detachment and increase the number of cells invading pelvic organs.

Microarray analysis of altered sphingolipid metabolism reveals prognostic significance of sphingosine kinase 1 in breast cancer

Beside their structural role for the cell membrane the family of sphingolipids act as effector molecules in signal transduction with links to various aspects of cancer initiation, progression and treatment response. The "sphingolipid rheostat" balances between apoptosis inducing ceramid and growth promoting sphingosine-1-phosphate. We analyzed gene expression of 43 proteins from this pathway in different subtypes of breast cancer using microarray data of 1,269 tumor samples (test set n=171; validation sets n=1098) and observed significant differences for several genes. Sphingosine kinase 1 (SPHK1), ceramide galactosyltransferase (UGT8), and Ganglioside GD3-Synthase (ST8SIA1) displayed higher expression among ER negative tumors. In contrast, glucosylceramidsynthase (GCS), dihydroceramidsynthases (LASS4, LASS 6) and acid ceramidase (ASAH1) were higher expressed in ER positive samples. Survival analysis revealed a worse outcome of patients with high SPHK1 expression. To avoid a confounding effect of the ER status we also restricted the analysis to 750 patients with ER positive tumors. Again a worse outcome was observed for tumors displaying high SPHK1 expression. While 75.8+/-1.9% of the patients with tumors low in SPHK1 expression were free of metastasis at 5 years, this was the case for only 64.9+/-3.6% of patients with tumors displaying high SPHK1 expression (P=0.008). Immunohistochemistry identified the carcinoma cells as the major source of SPHK1 expression in the tumor. The correlation of SPHK1 with a poor prognosis as well as its high expression among ER negative tumors are in line with the antiapoptotic and proliferative properties of its product sphingosine-1-phosphate. Targeting of the sphingolipid rheostat may thus open new treatment options.

Expression of membrane-type 5 matrix metalloproteinase in human endometrium and endometriosis

BACKGROUND

The metalloproteinases (MMPs) are a family of proteolytic enzymes involved in tissue remodeling and cell migration. Endometrial tissue remodeling proceeds during the menstrual cycle and requires a temporary and spatially balanced expression of several different MMPs. Various members of the MMPs also seem to play an important role in the invasion process of endometriosis; however, so far only a limited number of studies have focused on membrane-associated MMPs.

METHODS

The present study investigated the expression of membrane-type 5 metalloproteinase (MT5-MMP) in the human endometrium and endometriotic lesions by microarray hybridization, real-time polymerase chain reaction (PCR) and immunofluorescence.

RESULTS

Both the gene chip expression analyses as well as PCR indicated expression of MT5-MMP in normal human endometrium and strongly elevated transcript levels in most peritoneal endometriosis lesions analyzed. Moreover we detected enhanced MT5-MMP expression in the eutopic endometrium from patients suffering from endometriosis, further supporting a role of MT5-MMP in the formation of endometriosis. Immunohistochemical analysis was used to determine the intracellular localization and tissue distribution of MT5-MMP. While the MT5-MMP antigen expression could be clearly attributed to the membrane of epithelial cells, a highly complex differential immunohistochemical staining of MT5-MMP in the various compartments of endometrial tissue was observed. The strongest staining was seen in luminal epithelial cells, whereas endometrial glands frequently showed partial expression of MT5-MMP.

CONCLUSION

Our microarray analysis and real-time PCR of MT5-MMP transcripts may point to an elevated tissue remodeling and cell migration in endometrium from endometriosis patients as implied by the function of related MMPs.

Characterization of WNT7A expression in human endometrium and endometriotic lesions

OBJECTIVE

To characterize the expression of WNT7A in human eutopic and ectopic endometrium.

DESIGN

Experimental study using real-time polymerase chain reaction, laser microdissection, in situ hybridization, and immunofluorescence.

SETTING

University-based laboratory.

PATIENT(S)

Patients with and without endometriosis undergoing surgery for benign indications.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Relative expression values compared with housekeeping genes using real-time polymerase chain reaction. Detection of positive cells by immunofluorescence and in situ hybridization.

RESULT(S)

In endometriosis, statistically significant higher WNT7A mRNA expression was observed compared with eutopic endometrium. Expression of WNT7A was found in the luminal and glandular epithelial cells as well as stroma cells in endometrium and endometriosis by immunofluorescence, in situ hybridization, and polymerase chain reaction of laser microdissected tissue.

CONCLUSION(S)

The results of the present study suggest that WNT7A plays a role in the pathophysiology of endometriosis.

Breast cancers with stem cell-like features delineate endocrine responsiveness

10517

Background: Endocrine responsiveness is one of the most important characteristics of breast cancer. The negative association between expression of the estrogen receptor (ER) and proliferation detected in normal breast is frequently lost in breast cancers leading to receptor independent growth and poor patients’ prognosis. Methods: Microarray analysis of 171 breast cancer samples allowed the discrimination of a KIT+ tumor group by using a set of genes coregulated with the “stem cell factor” receptor KIT. Validation was performed on three independent datasets encompassing 637 samples. Furthermore the response to endocrine treatment only was analyzed in a dataset of 700 patients. Results: KIT+ tumors are transcriptionally related to proposed mammary stem cells. Two types of KIT+ tumors were identified which are characterized by their positive and negative ER status, respectively. The inverse link of ER expression and proliferation is perfectly conserved within the KIT+ tumor groups, while it is uncoupled among half of the KIT-Low ER positive tumors. Those “uncoupled” ER positive tumors with altered ER response are characterized by a prognosis inferior to the ER negative cancers despite an apparent positive ER status (hazard ratio for disease recurrence, 2.07; 95% CI 1.53–2.81; P<0.001). Moreover, the 5 and 10 year survival rates of lymph node negative “uncoupled” tumors are even worse than those of lymph node positive “normal” ER positive cancers. While all ER positive patients seem to profit from endocrine treatment the relative benefit was reduced in uncoupled tumors (21.2 % vs. 31.7 %). Conclusions: The classification of breast cancers according to this biologically based model identified clinical relevant tumor groups whose further characterization will have important implications. Moreover, since the ability to recognize malfunctions in ER pathways largely depends on an appropriate reference system, the KIT+ tumors could allow a dissection of estrogen responsiveness giving crucial insights for prediction of response to endocrine therapy.

No significant financial relationships to disclose.

Poor Outcome in Estrogen Receptor-Positive Breast Cancers Predicted by Loss of Plexin B1

PURPOSE

A common characteristic of mammary carcinomas is an inverse relationship between the estrogen receptor (ER) status and the proliferative activity of the tumor. Yet, a subset of ER-positive breast cancers is characterized by a high proliferation, suggesting malfunctions in ER responsiveness that influence the biological and therapeutic behavior of tumor cells. The expression of several ER-dependent genes seems to be dysregulated among those "uncoupled" tumors. One of those genes is plexin B1, a cell-surface receptor for the semaphorin Sema4D (CD 100). However, the biological role of plexin B1 in breast cancer is largely unknown.

EXPERIMENTAL DESIGN

Expression data of plexin B1 were obtained from Affymetrix microarray analysis of n = 119 breast cancer specimens. Validation was done by quantitative real-time PCR and protein expression was evaluated by immunohistochemistry. Expression data were compared with clinical characteristics as well as follow-up data of the disease.

RESULTS

Low plexin B1 expression levels characterize a more aggressive tumor phenotype. The expression of plexin B1 is strongly correlated with the ER status. However, even among ER-positive tumors, loss of plexin B1 is associated with an impaired prognosis of breast cancer patients in both univariate (all patients, P = 0.0062; ER positive, P = 0.0107) and multivariate analyses (all patients, P = 0.032; ER positive, P = 0.022). Immunohistochemistry reveals that the tumor cells themselves and not the endothelial cells are the major source of plexin B1 expression in the tumor.

CONCLUSION

Plexin B1 acts not only as a new important prognostic but should also represent a predictive marker indicating an endocrine resistance. These data give a new insight in markers that could be involved in endocrine dysregulation of breast cancer.

Utero-Tubal Sperm Transport and Its Impairment in Endometriosis and Adenomyosis

The uterus is composed of different smooth muscle layers that serve various functions. First, menstrual debris is expulsed at the time of the menses. Second, sperm is transported in the preovulatory phase to maximize fertility, and third, the human embryo is placed in an adequate setting during implantation. Endometriosis is a gynecologic disorder leading to severe pain symptoms such as severe pain during menstruation (dysmenorrhea), chronic pelvic pain, pain during sexual intercourse (dyspareunia), and abnormal uterine bleeding. Besides, endometriosis is often associated with female infertility and exhibits a massive impairment in the physiology of uterine contractility that can be documented by the in vivo examination method of hysterosalpingoscintigraphy (HSSG). In addition, endometriosis is associated in 80-90% of subjects with adenomyosis and our data clearly indicate that sperm transport is disturbed by hyperperistalsis when at least one focus of adenomyosis can be detected via magnetic resonance imaging (MRI) and turns into dysperistalsis (a complete failure in sperm transport capacity) when diffuse adenomyosis affecting all myometrial uterine muscle layers is detected. Hence, dysperistalsis is significantly associated with reduced spontaneous pregnancy rates. We therefore recommend MRI and HSSG in every sterility workup.

Uterotubal transport disorder in adenomyosis and endometriosis—a cause for infertility

OBJECTIVE

Uterine hyperperistalsis and dysperistalsis are common phenomena in endometriosis and may be responsible for reduced fertility in cases of minimal or mild extent of disease. Since a high prevalence of adenomyosis uteri has been well documented in association with endometriosis, we designed a study to examine whether hyperperistalsis and dysperistalsis are caused by the endometriosis itself or by the adenomyotic component of the disease.

DESIGN

A prospective observational study.

SETTING

University hospital, Department of Obstetrics and Gynaecology, Division of Reproductive Medicine and Gynaecologic Endocrinology with 300 in vitro fertilisation/intracytoplasmatic sperm injection cycles and 350 intrauterine insemination cycles/year.

POPULATION

Forty-one subjects with infertility and with laparoscopically proven endometriosis and patent fallopian tubes. Thirty-five subjects (85%) additionally showed signs of adenomyosis.

METHODS

All subjects underwent T2-weighed magnetic resonance imaging (MRI) and hysterosalpingoscintigraphy (HSSG) during the subsequent menstrual cycle. MRI revealed the extent of the adenomyotic component of the disease and the integrity of uterotubal transport capacity was evaluated by HSSG.

MAIN OUTCOME MEASURES

Influence of adenomyosis on uterotubal transport capacity in endometriosis.

RESULTS

In 35 of the 41 subjects (85%) with endometriosis, signs of adenomyosis were detected using T2-weighed MRI. Two of six (33%) subjects with no adenomyosis (group I) showed dysperistalsis and hyperperistalsis, compared with 14 of 24 (58%) women with focal adenomyosis (group II) and 10 of 11 (91%) women with diffuse adenomyosis (seven showed a failure in transport capacity and two contralateral transport).

CONCLUSIONS

Our data suggest that endometriosis is associated with impeded hyperperistaltic and dysperistaltic uterotubal transport capacity. However, adenomyosis is of even more importance, especially when diffuse adenomyosis is detected. Both forms of adenomyosis are commonly found in subjects with mild to moderate endometriosis. We suggest that the extent of the adenomyotic component in subjects with endometriosis explains much of the reduced fertility in subjects with intact tubo-ovarian anatomy.

[Management of abnormal uterine bleeding]

Bleeding disorders are one of the most frequent gynecological problems. The causes of bleeding disorders, and their frequency in particular, vary depending on the age of the woman affected. In premenopause and perimenopause, the most frequent causes are hormonal, in up to 90 % of cases, as well as organic changes in the uterus such as myomas, adenomyosis uteri, or endometrial polyps, in up to 70 % of cases. Coagulation defects cause increased bleeding, particularly in girls and young women, with no other recognizable cause. The treatment of bleeding disorders is causally based, although if the woman does not wish to have children, the therapeutic algorithm in many cases leads to similar symptomatic measures. The following therapeutic approaches, listed in order of increasing efficacy, are mainly used in the treatment of increased bleeding: gestagen, estrogen-gestagen combination, levonorgestrel (Mirena) and endometrial ablation or myoma enucleation, with comparable success rates, and finally hysterectomy. Embolization of the uterine artery in myomas or adenomyosis uteri, nonsteroidal anti-inflammatory drugs, and antifibrinolytic agents represent alternatives that may be useful in individual cases. The paper provides an overview of the various causes, useful diagnostic measures, and treatment options in uterine bleeding disorders.

c-kit: Identification of co-regulated genes by gene expression profiling and clinical relevance of two breast cancer subtypes with stem cell like features

622

Background: Expression of the proto-oncogene c-kit has been found in malignant tissue including a subset of breast cancers. c-Kit is also expressed in normal breast tissue and several authors found a loss of c-kit expression in breast carcinoma suggesting it might be involved in the growth control of mammary epithelium. Until now, only a few markers were described to be co-regulated with c-kit. To elucidate the possible role of c-kit in malignant transformation, we analyzed gene expression data of breast cancer patients. Methods: Tumor tissue of n=171 breast cancer patients were analyzed by gene expression profiling using Affymetrix Hg U133 Arrays (22,500 genes) and bioinformatic analyses. Tumor samples with high stromal and low epithelial cell content by gene expression profiling were excluded for further analysis. Validation was performed with n=100 independent samples. Results: A total of 10.5% of the tumors showed strong c-kit expression (2.5 fold above median). A careful dissection of global expression data revealed strong correlations of c-kit with the expression of a large cluster of genes containing several for whom c-kit coexpression was already described (HER1, CK-5/-17, PDGFR) as well as several members of the wnt signalling pathway, providing a possible novel link to mammary epithelial differentiation. Analysis of n=171 breast cancer samples according to this gene set allows the identification of putative “stem cell like” tumors (SCL) characterized by expression of several known stem cell markers. Surprisingly, a tight link of ER status and proliferation is restricted only to these SCL tumors but lost among non-SCL tumors. The clinical implications of our findings will be presented. Conclusions: For the first time these data bring together the description of two breast cancer subtypes identified by gene expression profiling with the actual stem cell model of the development of breast cancer.

No significant financial relationships to disclose.

[Integrin expression in eutopic and ectopic endometrium]

The significance of retrograde menstruation as a risk factor for endometriosis has been confirmed by numerous clinical observations. Integrins mediate both cell-cell and cell-matrix adhesion, and it is therefore suspected that integrins are involved in the development of endometriosis. Using immunohistochemistry, integrin expression in eutopic and ectopic endometrium is examined in endometriosis patients and control individuals. In nearly all cases, the glandular epithelial cells in the endometrium showed expression of alpha (2-), alpha (3)-, alpha (6)- and alpha (v)- integrin and a low percentage of expression of alpha (1)-, alpha (4)-, and alpha (5)-integrin. In comparison with eutopic endometrium, ectopic endometrium shows reduced expression of alpha (2)- and alpha (v)-integrin. Since no differences in alpha (2)- and alpha (v)-integrin expression were observed in eutopic endometrium between endometriosis patients and control individuals, it may be suspected that the reduced expression of these in ectopic endometrium is explained by influences in the altered environment -- e. g., in the peritoneal fluid -- on the ectopic endometrium.

[Clinical management of an androgen insensitivity syndrome]

The seldom occurring androgen insensitivity syndrome is characterised by male karyotype in a phenotypical women. We report on a complete androgen insensitivity syndrome with the rare coincidence of bilateral Fallopian tubes and a testicular intraepithelial neoplasia. Additionally we discuss aspects of incidence, molecular background, characteristics, diagnostic pitfalls and therapy against the background of the current literature.

[Suspicion for intraabdominal adhesions -- is open laparoscopy the gold standard?]

Laparoscopy is used for most surgical procedures in gynaecology. In general complications are rare. However, one of the most critical steps is the initial laparoscopic entry into the peritoneal cavity. According to the literature serious complications occur in approximately 1-2/1 000 cases. Whereas major vascular injuries are mainly recognised immediately, delayed recognition of bowel injuries is frequent. Complication rates of different entry procedures used in gynaecological laparoscopy are similar even in high risk patients (intraperitoneal adhesions, obesity). Utilising an open - instead a closed - entry (either by Veress needle or first trocar) technique or alternativ entry positions are suggested by some authors. This review presents data available in the literature and highlights that open laparoscopy is no gold standard.

The congruity between urine and cervical swab cultures in pregnant women with versus without amniotic fluid infection

INTRODUCTION

We observed the congruity of bacteria found in urine and cervix of pregnant women with amniotic fluid infection (AFI) compared to healthy controls.

PATIENTS AND METHODS

Over three years, we prospectively analysed urine and cervical swabs cultures in 120 pregnant women in gestational week 16-20. The patient population was divided in two groups: group I patients had clinical symptoms of AFI. The rest of the patients were designated as healthy controls (group II). Congruity between findings in both groups was observed. In patients with bacterial growth, antibiotic treatment was initiated as recommended and once ended - culture probes were repeated.

RESULTS

The rates of nonsignificant and significant bacteriuria were doubled in group I. Fifty-five percent (n = 33) of patients in group I had identical bacteria cultured both from the urine sample and cervical swab, in contrast to only 13.3 % in group II. Congruity was most pronounced for Klebsiella species and E. coli, the later being single most dominant isolate in regards to both cultures. After antimicrobial treatment, microbial eradication occurred in 15 patients (45.5 %). The observed incidences of abortions and preterm deliveries were significantly lower in patients with microbial eradication versus patients with microbial persistence.

CONCLUSION

Patients with clinical symptoms of AFI have high risk for bacteriuria identical to bacterial culture from cervical swab. Antimicrobial treatment was effective only partially where indicated. Screening for eradication is recommended and consensus on the most appropriate therapy is needed.

[New aspects in diagnosis and therapy of endometriosis]

Endometriosis and adenomyosis show a high prevalence and can be regarded as different symptoms of a unique disease - the dislocation of basal endometrium. Diagnostic methods for detecting adenomyosis are transvaginal sonography (TVS) or T-2-weighed magnetic resonance imaging (MRI). Patients with endometriosis show a significant impairment of utero-tubal sperm transport capacity, which is even increased the stronger the adenomyotic component of the disease is. Adenomyosis can be regarded as a cause for infertility especially in minor and mild forms of endometriosis and is therefore often followed by IVF/ICSI-treatment. Infertility patients with endometriosis should be counselled for intensive infertility treatment. Without a current wish for conception, fertility potential should be preserved by hormonal suppression of uterine peristalsis in order to avoid progression of the disease.

[Alternatives to hysterectomy: a review]

Total hysterectomy is considered as gold standard in the treatment of symptomatic uterine fibroids in women without reproductive wishes. However an increasing number of patients asked for alternatives to hysterectomy. Myomectomy, endometrial ablation, hormonal treatment, uterine artery embolization, and supracervical hysterectomy may be useful in the treatment uterine fibroids in an individual patient.