CIBICI   14215
CENTRO DE INVESTIGACION EN BIOQUIMICA CLINICA E INMUNOLOGIA
Unidad Ejecutora - UE
artículos
Título:
Nuclear expression of KLF6 tumor suppressor factor is highly associated with overexpression of ERBB2 oncoprotein in ductal breast carcinomas.
Autor/es:
GEHRAU RC; D'ASTOLFO DS; DUMUR CI; BOCCO JL* (CORRESPONDIG AUTHOR); KORITSCHONER NP
Revista:
PLOS ONE
Editorial:
PUBLIC LIBRARY SCIENCE
Referencias:
Lugar: San Francisco, CA 94107 - USA; Año: 2009 vol. 28 p. 1 - 11
ISSN:
1932-6203
Resumen:
Background: Kruppel-like factor 6 (KLF6) is an evolutionarily conserved and ubiquitously expressed protein that belongs tothe mammalian Sp1/KLF family of transcriptional regulators. Though KLF6 is a transcription factor and harbors a nuclearlocalization signal it is not systematically located in the nucleus but it was detected in the cytoplasm of several tissues andcell lines. Hence, it is still not fully settled whether the tumor suppressor function of KLF6 is directly associated with its abilityto regulate target genes. Methodology/Principal Findings: In this study we analyzed KLF6 expression and sub-cellular distribution by immunohistochemistry in several normal and tumor tissues in a microarray format representing fifteen human organs. Results indicate that while both nuclear and cytoplasmic distribution of KLF6 is detected in normal breast tissues, breast carcinomas express KLF6 mainly detected in the cytoplasm. Expression of KLF6 was further analyzed in breast cancer tissues overexpressing ERBB2 oncoprotein, which is associated with poor disease prognosis and patient’s survival. The analysis of 48 ductal carcinomas revealed a significant population expressing KLF6 predominantly in the nuclear compartment (X2 p = 0.005; Fisher p = 0.003). Moreover, this expression pattern correlates directly with early stage and small ductal breast tumors and linked to metastatic events in lymph nodes. Conclusions/Significance: Data are consistent with a preferential localization of KLF6 in the nuclear compartment of early stage and small HER2-ERBB2 overexpressing ductal breast tumor cells, also presenting lymph node metastatic events. Thus, KLF6 tumor suppressor could represent a new molecular marker candidate for tumor prognosis and/or a potential target for therapy strategies.