PRRX1 and PRRX2 distinctively participate in pituitary organogenesis and a cell-supply system

Abstract

Paired-related homeobox transcription factors, PRRX1 and PRRX2, are known to be important factors for craniofacial and limb morphogenesis. We recently cloned Prrx2 from the porcine adult pituitary cDNA library and found that only PRRX1 is present in the rat embryonic pituitary. In this study, we re-investigated the temporospatial expression and localization of PRRX1 and PRRX2 in the rat pituitary throughout life. The persistent expression of Prrx1 was ascertained after the middle stage of embryonic development, whereas significant expression of Prrx2 was found only in the postnatal pituitary. Immunohistochemistry confirmed that PRRX1-positive cells appeared inside the pituitary on embryonic day 16.5 in the marginal cell layer (MCL), a pituitary stem/progenitor cell niche, and the expanding parenchyma of the anterior pituitary. In contrast, PRRX2-positive cells first appeared in the anterior lobe and intermediate lobe sides of the MCL around postnatal day 30 when the postnatal pituitary growth wave had almost terminated. Immunostaining for PRRX1 with a stem/progenitor cell marker SOX2, a pituitary progenitor marker PROP1, or pituitary hormones revealed that PRRX1 localized in cells in the transition process from the multipotent progenitor stage to the early stage of terminal differentiation throughout life. PRRX2 emerged in cells positive for SOX2 but negative for PROP1 in the anterior and intermediate lobe sides of the postnatal MCL. Thus, PRRX1 and PRRX2 might participate distinctly in pituitary organogenesis and the postnatal cell-supply system.

Silencing of Prrx2 Inhibits the Invasion and Metastasis of Breast Cancer both In Vitro and In Vivo by Reversing Epithelial-Mesenchymal Transition

“…A recent study reported that Prrx2 as a TGF-β-induced factor that enhances invasion and migration in breast cancer [13]. Similarly, the role of Prrx2 has been implicated in acute myeloid leukaemia, in which translocation was mediated by the fusion of the nucleoporin gene Nup98, and Prrx2 has been identified as a new transcriptional factor in metastatic gastric cancer [14, 15]. However, the molecular mechanism of Prrx2 in breast cancer requires further investigation.…”

Pituitary Stem Cells During Normal Physiology and Disease

“…This side population has since been described for pituitaries of other vertebrates (Chen et al 2005(Chen et al , 2006van Rijn et al 2012). In time, additional markers of cells with this in vitro self-renewal capacity have been put forward to refine the characterisation of PSCs, including Nestin, PROP1, SOX9, GFRα2 and PRX1/2 (Gleiberman et al 2008;Yoshida et al 2009;Rizzoti et al 2013;GarciaLavandeira et al 2009;Higuchi et al 2014). In the postnatal rodent gland in vivo, SOX2-positive cells displayed a high degree of overlap with other proposed stem cell markers such as SOX9 (Rizzoti et al 2013), PROP1 (Yoshida et al 2009(Yoshida et al , 2011, and PRX1/2 (Higuchi et al 2014).…”

“…In time, additional markers of cells with this in vitro self-renewal capacity have been put forward to refine the characterisation of PSCs, including Nestin, PROP1, SOX9, GFRα2 and PRX1/2 (Gleiberman et al 2008;Yoshida et al 2009;Rizzoti et al 2013;GarciaLavandeira et al 2009;Higuchi et al 2014). In the postnatal rodent gland in vivo, SOX2-positive cells displayed a high degree of overlap with other proposed stem cell markers such as SOX9 (Rizzoti et al 2013), PROP1 (Yoshida et al 2009(Yoshida et al , 2011, and PRX1/2 (Higuchi et al 2014). We confirmed that SOX2-positive cells did not overlap with differentiation markers but we sought to determine if they were able to give rise to all the differentiated lineages in vivo.…”

Stem Cells in Neuroendocrinology

“…This side population has since been described for pituitaries of other vertebrates van Rijn et al 2012). In time, additional markers of cells with this in vitro self-renewal capacity have been put forward to refine the characterisation of PSCs, including Nestin, PROP1, SOX9, GFRα2 and PRX1/2 (Gleiberman et al 2008;GarciaLavandeira et al 2009;Higuchi et al 2014). In the postnatal rodent gland in vivo, SOX2-positive cells displayed a high degree of overlap with other proposed stem cell markers such as SOX9 ), PROP1 , and PRX1/2 .…”