Gene expression changes with differentiation of cord blood stem cells to respiratory epithelial cells: A preliminary observation

Department of Laboratory Medicine and Pathology, University of Minnesota, 420 Delaware Street SE, MMC609, Minneapolis, MN 5545, USA.
Stem Cell Research & Therapy (Impact Factor: 3.37). 04/2011; 2(2):19. DOI: 10.1186/scrt60
Source: PubMed


Owing to wide availability, low cost and avoidance of ethical concerns, umbilical cord blood (UCB) provides an attractive source of stem cells for investigational and therapeutic uses. In this study, we sought to characterize the gene expression changes as stem cells from UCB differentiate toward alveolar type II pneumocytes (ATII).
Control and experimental cells were cultured in maintenance medium (mesenchymal stem cell growth medium) or differentiation medium (small airway growth medium (SAGM)), respectively, for 8 days. Total RNA was isolated from control and experimental groups for gene expression profiling and real-time polymerase chain reaction assay.
Analysis of only mixed cell lines (n = 2) with parameters including a P value of 0.01 and an intergroup gap of 2.0 yielded a set of 373 differentially expressed genes. Prominently upregulated genes included several genes associated with ATII cells and also lung cancers: ALDH3A1, VDR and CHKA. Several upregulated genes have been shown to be integral or related to ATII functioning: SGK1, HSD17B11 and LEPR. Finally, several upregulated genes appear to play a role in lung cancers, including FDXR and GP96. Downregulated genes appear to be associated with bone, muscle and central nervous system tissues as well as other widespread tissues.
To the best of our knowledge, this accounting of the gene expression changes associated with the differentiation of a human UCB-derived stem cell toward an ATII cell represents the first such effort. Dissecting which components of SAGM affect specific gene regulation events is warranted.

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Available from: David H Mckenna
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    • "Interestingly, in human patients affected with colon carcinoma, these genes (ALDH3A1, CLDN2 and CTEN) also have been associated with poor clinical outcomes. Indeed, ALDH3A1 expression and activity has been found to be closely correlated with resistance to apoptosis induced by cytotoxic effects [65,68] or by some chemotherapeutic agents, such as cyclophosphamide [69,70] and oxazphosphorines [71]. The analysis of mRNA and protein expression using a total of 309 patient samples revealed that CLDN2 expression is significantly increased in colorectal cancer, and correlates with cancer progression and tissue invasion [32,33,67]. "
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    ABSTRACT: Background Metastasis accounts for the majority of deaths from cancer. Although tumor microenvironment has been shown to have a significant impact on the initiation and/or promotion of metastasis, the mechanism remains elusive. We previously reported that HCT-8 colon cancer cells underwent a phenotypic transition from an adhesive epithelial type (E-cell) to a rounded dissociated type (R-cell) via soft substrate culture, which resembled the initiation of metastasis. The objective of current study was to investigate the molecular and metabolic mechanisms of the E-R transition. Methods Global gene expressions of HCT-8 E and R cells were measured by RNA Sequencing (RNA-seq); and the results were further confirmed by real-time PCR. Reactive oxygen species (ROS), anoikis resistance, enzyme activity of aldehyde dehydrogenase 3 family, member A1 (ALDH3A1), and in vitro invasion assay were tested on both E and R cells. The deformability of HCT-8 E and R cells was measured by atomic force microscopy (AFM). To study the in vivo invasiveness of two cell types, athymic nude mice were intra-splenically injected with HCT-8 E or R cells and sacrificed after 9 weeks. Incidences of tumor development and metastasis were histologically evaluated and analyzed with Fisher’s exact test. Results Besides HCT-8, E-R transition on soft substrates was also seen in three other cancer cell lines (HCT116, SW480 colon and DU145 prostate cancer). The expression of some genes, such as ALDH3A1, TNS4, CLDN2, and AKR1B10, which are known to play important roles in cancer cell migration, invasion, proliferation and apoptosis, were increased in HCT-8 R cells. R cells also showed higher ALDH3A1 enzyme activity, higher ROS, higher anoikis resistance, and higher softness than E cells. More importantly, in vitro assay and in vivo animal models revealed that HCT-8 R cells were more invasive than E cells. Conclusions Our comprehensive comparison of HCT-8 E and R cells revealed differences of molecular, phenotypical, and mechanical signatures between the two cell types. To our knowledge, this is the first study that explores the molecular mechanism of E-R transition, which may greatly increase our understanding of the mechanisms of cancer mechanical microenvironment and initiation of cancer metastasis.
    Full-text · Article · May 2014 · Molecular Cancer
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    • "Perinatal stem cells are an ideal cell source in terms of availability, the fewer number of ethical concerns, less DNA damage, and so on [16,17]. The biological characteristics of CB-derived HSCs/HPCs were characterized in numerous studies [4,6]. SALL4 may act as a critical regulator of the fate of hematopoietic cells. "
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    ABSTRACT: Introduction SALL4 and BMI-1 are important factors in hematopoiesis. Placental tissue (PT) and umbilical cord blood (CB) are rich in hematopoietic stem/progenitor cells (HSCs/HPCs), but their SALL4 and BMI-1 expression levels remain unknown. Methods Real-time PCR was used to determine the expression level of these genes in PT and CB from ten cases, and ten healthy donors were used as controls. Results A significantly higher BMI-1 and SALL4 gene expression level was found in PT (median: 17.548 and 34.362, respectively) than in cord blood mononuclear cells (CBMCs) (median: 2.071 and 11.300, respectively) (P = 0.0001 and P = 0.007) and healthy peripheral blood mononuclear cells (PBMCs) (median: 0.259 and 0.384, respectively) (P = 0.001 and P <0.0001), and their expression level was lower in PBMCs than in CBMCs (P = 0.029 and P = 0.002). A positive correlation between the BMI-1 and SALL4 genes was found in the PT and CB groups, while there was no significant correlation between these genes in the healthy group. There was also no significant correlation between the expression level of each gene in PT and CB. Conclusions These results describe the characteristic features of the BMI-1 and SALL4 gene expression pattern in placental tissue and cord blood. Placental tissue with higher expression level of both genes may be considered as a potential resource for SALL4-related HPC expansion.
    Full-text · Article · Apr 2013 · Stem Cell Research & Therapy
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    • "Sueblinvong et al. [29] previously reported respiratory epithelial gene expression, including SP-C expression, in human cord blood-derived mesenchymal stem cells cultured in specialized airway growth media and/or specific growth factors such as KGF and retinoic acid. Similarly, Berger et al. [30,31] reported respiratory epithelial differentiation in cord blood-derived multilineage progenitor cells cultured and differentiated in standard mesenchymal stem cell growth medium and small airway growth medium (SAGM), respectively. To our knowledge, this is the first study to demonstrate that cord blood-derived CD34+ cells, as well, have the capacity to undergo in vitro respiratory epithelial cell-like differentiation when exposed to the appropriate differentiation agents. "
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    Full-text · Article · Mar 2013 · Respiratory research
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