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Jeon, Byeong-Gyun,Kumar, B Mohana,Kang, Eun-Ju,Maeng, Geun-Ho,Lee, Yeon-Mi,Hah, Young-Sool,Ock, Sun-A,Kwack, Dae-Oh,Park, Bong-Wook,Rho, Gyu-Jin Potamitis Press 2011 Anticancer research Vol.31 No.12
<P>We investigated the effects of sodium meta-arsenite (NaAsO(2)) on human cancer cells (MDA-MB-231, MCF-7 and U-87 MG), dental papilla tissue stem cells (DPSCs) and somatic cells [MRC-5 fetal fibroblasts and adult muscle cells (MCs)] by examining telomeric properties, endogenous reverse transcriptase (RT) activity and the expression of tumorigenesis-linked genes. Half maximal inhibitory concentration (IC(50)) values were higher in DPSCs and MCs, possessing longer telomere lengths when compared to cancer cells. Levels of telomerase and RT activity, and the expression of protein 53 (p53), B-cell lymphoma 2 (BCL2), nuclear factor kappa-light-chain-enhancer of activated B-cells (NFκB), transforming growth factor beta (TGFβ) and vascular endothelial growth factor (VEGF) were significantly lower in cancer cells following sodium meta-arsenite treatment, whereas the effect was absent or marginally detected in DPSCs and somatic cells. Collectively, sodium meta-arsenite effectively induced cellular cytotoxicity by inhibiting telomerase and RT activity, and down-regulating transcript levels in cancer cells with shorter telomere lengths, whereas more tolerance was evident in DPSCs and somatic cells possessing longer telomere lengths.</P>
Porcine Tissue Specific Stem Cells and Their Potential for Germ Cell Differentiation
B. Mohana Kumar,Gyu‐Jin Rho 한국동물생명공학회(구 한국동물번식학회) 2011 발생공학 국제심포지엄 및 학술대회 Vol.2011 No.1
Some tissues retain extensive regeneration potential through out adult life and remain as active sites of cell production. Various cell types present in tissues are being produced through proliferation and progressive specialization from a pool of stem cells. In this regard, adult stem cells (ASCs) are multipotent progenitor cells with an ability to proliferate in vitro and undergo extensive self-renewal and differentiation into a wide range of cell types, including adipocytes, chondrocytes, osteocytes, myocytes, cardiomyocytes and neurons. In addition, recent studies showing the abilities of ASCs in generating oocytes-like cells (OLCs) present new perspectives to understand the specification and interaction during the germ cell formation and oogenesis. In the present study, ASCs were established from skin, adipose and ovarian tissues of minipigs. Isolated cells exhibited a fibroblast-like morphology with higher proliferation potential and stronger alkaline phosphatase (AP) activity. ASCs from all tissues expressed pluripotent transcriptional factors, such as Oct-3/4, Nanog and Sox-2 and phenotypic markers, including CD29, CD44, CD90 and vimentin. Further, ASCs were successfully dIfferentiated into osteocytes, adipocytes and neuron-like cells. Upon induction in oogenesis specific media, all ASCs were capable of differentiation into OLCs by exhibiting distinct morphological features. Generated OLCs expressed a range of germ cell specific markers, such as Vasa, deleted in Azoospermia-like (DAZL) factor, stella, c-kit, c-Mos, synaptonemal complex protein 3 (SCP-3), growth differentiation factor 9b (GDF- 9b), zona pellucida C (ZPC) and follicle stimulating hormone receptor (FSHR) at different time points of induction. Differentiated OLCs were also positive for the expression of Vasa and DAZL protein markers. Our findings showing that OLCs can be generated from ASCs of different tissue origin may offer pig as a suitable model for designing transgenic application strategies for reproductive tissue therapy. However, further studies are needed to understand the cellular and molecular mechanisms involved in germ cell differentiation from tissue specific stem cells.
Kumar, B Mohana,Maeng, Geun-Ho,Lee, Yeon-Mi,Lee, Jeong-Hyeon,Jeon, Byeong-Gyun,Ock, Sun-A,Kang, Taeyoung,Rho, Gyu-Jin Elsevier ; Kluwer Academic Publishers 2013 Veterinary research communications Vol.37 No.1
<P>Treatment of somatic cells with DNA methylation and histone deacetylation inhibitors has been hypothesized to improve the potential reprogramming after nuclear transfer (NT). The objective of this study was to investigate the developmental competence and gene expression during the porcine preimplantation development of in vitro fertilized (IVF) and embryos cloned with porcine fetal fibroblasts (pFF) (pFF-NT), and pFF treated by 0.5 μM 5-azacytidine (5-azaC) (pFF+5-azaC-NT) or 1.0 mM sodium butyrate (NaB) (pFF+NaB-NT). IVF embryos had significantly (P < 0.05) higher blastocyst rates (27.7 2.6 %) and total cell numbers (46.7 3.9). However, NT embryos from pFF+5-azaC and pFF+NaB showed enhanced developmental potential with significantly (P < 0.05) higher rates of blastocysts (21.3 2.9 % and 22.4 1.7 %, respectively) than those from pFF (15.1 2.5 %). Further, NT embryos from pFF+5-azaC and pFF+NaB (33.8 4.1 and 35.7 5.2, respectively) had significantly (P < 0.05) higher total cell numbers than those from pFF (24.6 3.5). Differential expression pattern of genes involved in DNA methylation (DNA methyltransferases- DNMT1, DNMT2, DNMT3A and DNMT3B), histone acetylation (histone acetyltransferase 1- HAT1) and histone deacetylation (histone deacetylases- HDAC1, HDAC2 and HDAC3) were observed in NT embryos when compared to IVF counterparts. However, the relative expressions of genes in pFF+5-azaC-NT and pFF+NaB-NT groups were largely comparable to those of IVF embryos than pFF-NT embryos. In conclusion, modification of the epigenetic status by reducing DNA methylation or enhancing histone acetylation levels in pFF improved the developmental rates, total cell number and the transcription profile of porcine NT embryos. Thus, somatic cells with relatively hypomethylated or hyperacetylated genome may enhance reprogramming efficiency in porcine NT.</P>