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.
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 cancerpatients 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.
Authors: Thomas Worzfeld; Jakub M Swiercz; Mario Looso; Beate K Straub; Kishor K Sivaraj; Stefan Offermanns Journal: J Clin Invest Date: 2012-03-01 Impact factor: 14.808
Authors: Eugen Ruckhäberle; Thomas Karn; Lars Hanker; Josef Schwarz; Peter Schulz-Knappe; Karsten Kuhn; Gitte Böhm; Stefan Selzer; Neukum Erhard; Knut Engels; Uwe Holtrich; Manfred Kaufmann; Achim Rody Journal: Breast Care (Basel) Date: 2010-02-16 Impact factor: 2.860
Authors: Tomoyo Okada; Surajit Sinha; Ilaria Esposito; Gaia Schiavon; Miguel A López-Lago; Wenjing Su; Christine A Pratilas; Cristina Abele; Jonathan M Hernandez; Masahiro Ohara; Morihito Okada; Agnes Viale; Adriana Heguy; Nicholas D Socci; Anna Sapino; Venkatraman E Seshan; Stephen Long; Giorgio Inghirami; Neal Rosen; Filippo G Giancotti Journal: Nat Cell Biol Date: 2014-12-22 Impact factor: 28.824