Isolation and functional characterization of murine prostate stem cells

Abstract

The ability to isolate prostate stem cells is essential to explore their role in prostate development and disease. In vitro prostate colonyand sphere-forming assays were used to quantitatively measure murine prostate stem/progenitor cell enrichment and self-renewal. Cell surface markers were screened for their ability to positively or negatively enrich for cells with enhanced growth potential in these assays. Immunohistochemical and FACS analyses demonstrate that specific cell surface markers can be used to discriminate prostate stromal (CD34 ؉ ), luminal epithelial (CD24 ؉ CD49f ؊ ), basal epithelial (CD24 ؉ CD49f ؉ ), hematopoietic (CD45 ؉ , Ter119 ؉ ), and endothelial (CD31 ؉ ) lineages. Sorting for cells with a CD45 ؊ CD31 ؊ Ter119 ؊ Sca-1 ؉ CD49f ؉ antigenic profile results in a 60-fold enrichment for colony-and sphere-forming cells. These cells can self-renew and expand to form spheres for many generations and can differentiate to produce prostatic tubule structures containing both basal and luminal cells in vivo. These cells also localize to the basal cell layer within the region of the gland that is proximal to the urethra, which has been identified as the prostate stem cell niche. Prostate stem cells can be isolated to a purity of up to 1 in 35 by using this antigenic profile. The remarkable similarity in cell surface profile between prostate and mammary gland stem cells suggests these markers may be conserved among epithelial stem cell populations.CD49f ͉ integrin ␣6 ͉ Sca-1 ͉ CD24 heat-stable antigen ͉ stem cell niche S tem cells are of interest clinically because of their potential to repair damaged tissues, treat degenerative diseases, and because of their purported role in tumor initiation. The ability to identify and isolate stem cells is necessary to study their specialized biology. Enrichment for many types of tissue stem cells has been achieved by using cell surface markers. Murine hematopoietic stem cells can be enriched by sorting Lin Ϫ Thy-1 lo Sca-1 ϩ ckit ϩ cells from the bone marrow (1). Recent studies suggest that even better purity can be achieved by further sorting based on expression of the SLAM family receptors CD150 and CD48 (2). Bronchioavelolar stem cells can be isolated from their niche at the bronchioalveolar duct junction (BADJ) by sorting cells with a CD45 Ϫ CD31 Ϫ Sca-1 ϩ CD34 ϩ profile (3). Data from two recent reports show that mouse mammary stem cells possess a Lin Ϫ Sca-1 ϩ CD140a Ϫ CD24 ϩ CD49f ϩ CD29 ϩ cell surface profile and can be isolated to a purity of up to 1 in 20 by using subsets of these markers (4, 5).The presence of stem cells in the prostate first was proposed to explain the seemingly inexhaustible capacity of the organ to regenerate during androgen cycling experiments (6). The identification of side-population cells and replication quiescent BrdU label-retaining cells further suggests that stem cells exist in the gland (7,8). Several studies have enriched for primitive prostate cells by using cell surface markers. Richardson et al. (9) demonstrated that th...

CD44+CD24− prostate cells are early cancer progenitor/stem cells that provide a model for patients with poor prognosis

“…Identification of a small CD44 þ CD24 À subpopulation in prostate cell lines with increased clonogenic properties Given the reported similarity between murine breast and prostate stem cells (Lawson et al, 2007) and the recent identification of a CD44 þ CD24 À subpopulation of breast cancer cells that have an increased tumorigenic capacity (Al-Hajj et al, 2003), we sought to identify and characterise CD44 þ CD24 À cells in human prostate cell lines. We identified a CD44 þ CD24 À subpopulation with varying abundance in different prostate cancer cell lines.…”

“…In breast cancer, previous analysis identified CD44 þ CD24 À cells as both clonogenic and tumorigenic (Al-Hajj et al, 2003). Recently, work with mouse prostate stem-like cells revealed commonalities between mouse prostate stem-like cells and stem-like cells originating from other tissues, including breast (Lawson et al, 2007).…”

Stem cells in the heart: What's the buzz all about?—Part 1: Preclinical considerations

“…In fact, spontaneous sphere formation by progenitor cells is not a phenomenon unique to progenitors isolated from the heart. Sphere formation also has been observed with neural, 30 retinal, 31 mammary, 32 kidney, 33 and prostate 34 progenitors and is thought to play a role in determining cell phenotype and survival. 35 We were highly successful using the cardiosphere method.…”

CD24: from A to Z

“…20 As a glycosyl phosphatidylinositol-anchor molecule, CD24 mediates signal transduction by recruiting Src family protein tyrosine kinases (PTKs) including c-fgr, lyn and lck via membrane rafts, and activates the mitogen-activated protein kinase pathway, which involves B-and T-cell development and apoptosis, cell binding and granulocyte oxidative burst. 21 58,59 and many types of cancer cells. 60 As a rule, CD24 tends to be expressed at higher levels in progenitor cells and metabolically active cells and to a lesser extent in terminally differentiated cells.…”