ERα36, a new variant of the ERα is expressed in triple negative breast carcinomas and has a specific transcriptomic signature in breast cancer cell lines

Triple negative breast cancer is deprived of estrogen receptor alpha (ERα), progesterone receptor (PR) and HER-2 protein. It constitutes the most heterogeneous and aggressive group of breast carcinomas, for which identification of novel characteristics and characterization of putative targets becomes very demanding. In the present work we have assayed the expression of ERα36, a recently identified ERα variant of 36 kDa, in a series of triple negative breast cancers, in relation to the clinical behavior and other clinico-pathological features of the tumors. While widely expressed within the cytoplasm in almost all tumors, we found that exclusively the membrane/submembrane expression of the receptor exhibits a correlation with patient's survival. Moreover, membrane ERα36 correlates in an inverse manner with the expression of miRNA210, a pro-angiogenic miR, with high prognostic relevance in triple negative carcinomas. A thorough transcriptomic, pharmacological-based approach in breast cancer cell lines, revealed an early (direct) transcriptional signature of the receptor activation, related to immune system processes and T-cell differentiation, RNA biosynthesis, regulation of metabolism, VEGF signaling and regulation of the cell cycle, with a down-regulation of CREB, NFκB and STATs transcription factors. Finally, ERα36 expression is not limited within breast cancer epithelial linen, but is equally identified in tumor vasculature, peritumoral fat tissue, lymphocytic infiltrate and stromal fibroblasts. In light of the above, ERα36 could represent a major counterpart in triple negative breast cancer. © 2011 Elsevier Inc. All rights reserved.SCOPUS: cp.jinfo:eu-repo/semantics/publishe

Correlation between pairs of the TNFSF ligands and receptors identified in our series of 56 gliomas.

<p>The Spearman's correlation coefficient (rho) is reported, together with the number of cases and statistical significance. H-score (as presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0083250#pone.0083250.s012" target="_blank">Table S4</a> is used for the analysis.</p><p>*. Correlation is significant at the 0.05 level (1-tailed).</p><p>**. Correlation is significant at the 0.01 level (1-tailed).</p

Representative images of BAFF, TWEAK and their cognate receptor BCMA, TACI and Fn14 expression in vascular endothelial cells of human glioma specimens.

<p><b>Upper row:</b> vascular endothelium immunoreactivity for CD31 (<b>A</b>), Fn14 (<b>B</b>), and TWEAK (<b>C</b>). <b>Lower row</b>: vascular endothelium immunoreactivity for BAFF (<b>D</b>) and TACI (<b>E</b>). In panel <b>F</b>, vascular endothelial immunoreactivity for BCMA (direct immunofluorescence assay, with anti-BCMA-FITC antibody. Similar results were obtained by indirect immunostaining with non-fluorescent anti-BCMA antibody (not shown). Arrows show tumor vessels. APRIL was not detected in endothelial cells (not shown). All pictures are taken under 20× magnification. Bar = 200 µm. Inserts in each panel show a higher magnification of a representative part of the vessel.</p

Quantification of BAFF, APRIL, TWEAK and their receptors in Low (WHO I & II) and high grade gliomas (WHO grade III & IV).

<p>Data are expressed as mean±SEM and medians of the corresponding H-score of tumors, presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0083250#pone.0083250.s012" target="_blank">Table S4</a>. Statistical analysis was performed by one way ANOVA, with Bonferroni correction.</p

Representative images of BAFF, APRIL, TWEAK and their cognate receptors as well as inflammatory markers CD3, CD20, CD68 expression in human glioma specimens.

<p>Parallel immunostaining of BAFF, APRIL, TWEAK, BCMA, TACI, Fn14 and inflammatory markers CD3, CD20 and CD68 showing that the main source of these TNFSF members are reactive and tumoral glial cells <i>per se</i> in areas with minimal inflammation. Red arrows (black in 3B) indicate gemistocytes immunopositive for BAFF (<b>A</b>), APRIL (<b>B</b>), TWEAK (<b>C</b>), TACI (<b>D</b>), BCMA (<b>E</b>) and Fn14 (<b>F</b>). Gemistocytes negative for lymphocytic CD3 (<b>G</b>), CD20 (<b>H</b>) and panmacrophage CD68 (<b>I</b>) immunostaining. CD68 immunopositive macrophages/microglia and monocytes in I. All pictures are taken under 40× magnification.</p

Quantification of BAFF, APRIL, TWEAK and their receptors in gliomas, stratified by grade.

<p>Data are expressed as mean±SEM and medians of the corresponding H-score of tumors, presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0083250#pone.0083250.s012" target="_blank">Table S4</a> in <b>A</b> and bar graph (mean±SEM) in <b>B</b>.</p

BAFF, APRIL, TWEAK, BCMA, TACI and Fn14 Proteins Are Related to Human Glioma Tumor Grade: Immunohistochemistry and Public Microarray Data Meta-Analysis

<div><p>Gliomas are common and lethal tumors of the central nervous system (CNS). Genetic alterations, inflammatory and angiogenic processes have been identified throughout tumor progression; however, treatment still remains palliative for most cases. Biological research on parameters influencing cell survival, invasion and tumor heterogeneity identified several cytokines interfering in CNS inflammation, oxidative stress and malignant transformation, including TNF-superfamily (TNFSF) members. In this report we performed a meta-analysis of public gene-array data on the expression of a group of TNFSF ligands (BAFF, APRIL, TWEAK) and their receptors (BAFF-R, TACI, BCMA, Fn14) in gliomas. In addition, we investigated by immunohistochemistry (IHC) the tumor cells' expression of these ligands and receptors in a series of 56 gliomas of different grade. We show that in IHC, BAFF and APRIL as well as their cognate receptors (BCMA, TACI) and Fn14 expression correlate with tumor grade. This result was not evidenced in micro-arrays meta-analysis. Finally, we detected for the first time Fn14, BAFF, BCMA and TACI in glioma-related vascular endothelium. Our data, combined with our previous report in glioma cell lines, suggest a role for these receptors and ligands in glioma biology and advance these molecules as potential markers for the classification of these tumors to the proliferative, angiogenic or stem-like molecular subtype.</p></div

Representative immunohistochemical images of APRIL, BAFF, TWEAK and their cognate receptor expression in human gliomas.

<p>All pictures are taken under 20× magnification. APRIL immunoreactivity (A,B) increases from low grade to higher grade lesions. Note the intense staining in larger cells, while smaller ones are negative (A). BAFF immunoreactivity declines from lower grade (C, diffuse and intense), to higher grade gliomas (D). TACI displayed higher immunoreactivity in higher grade gliomas (F) than in low grade ones (E). Similar findings were found for BCMA as well (low grade G, high grade F). Low and high grade tumors displayed heterogeneous regarding percentage of positive cells and/or intensity of staining for TWEAK and Fn14. Here representative photos from Grade III gliomas for TWEAK (I, J) and Fn14 (K, L), respectively are shown.</p