49. Shalom-Barak T, Quach J, Lotz M (1998) Interleukin-17-induced gene expression in articular chondrocytes is associated with activation of mitogen- activated protein kinases and NF-kappaB. J Biol Chem 273: 27467–27473. 50. Ogura H, Murakami M, Okuyama Y, Tsuruoka M, Kitabayashi C, et al. (2008) Interleukin-17 promotes autoimmunity by triggering a positive-feedback loop via interleukin-6 induction. Immunity 29: 628–636. 51. Chen Y, Thai P, Zhao YH, Ho YS, DeSouza MM, et al. (2003) Stimulation of airway mucin gene expression by interleukin (IL)-17 through IL-6 paracrine/ autocrine loop. J Biol Chem 278: 17036–17043. 52. Huang H, Kim HJ, Chang E-J, Lee ZH, Hwang SJ, et al. (2009) IL-17 stimulates the proliferation and differentiation of human mesenchymal stem cells: implications for bone remodeling. Cell Death Differ, in process (doi: 10.1038/cdd.2009.74). 53. Bartsch G, Yoo JJ, De Coppi P, Siddiqui MM, Schuch G, et al. (2005) Propagation, expansion, and multilineage differentiation of human somatic stem cells from dermal progenitors. Stem Cell Develop 14: 337–348. 54. Toma JG, Akhavan M, Fernandes KJ, Barnabe´-Heider F, Sadikot A, et al. (2001) Isolation of multipotent adult stem cells from the dermis of mammalian skin. Nat Cell Biol 3: 778–784. 55. Fernandes KJ, McKenzie IA, Mill P, Smith KM, Akhavan M, et al. (2004) A dermal niche for multipotent adult skin-derived precursor cells. Nat Cell Biol 6: 1082–1093. 56. Toma JG, McKenzie IA, Bagli D, Miller FD (2005) Isolation and characterization of multipotent skin-derived precursors from human skin. Stem Cells 23: 727–737. 57. Zhang QZ, Wu Y, Ann DK, Messadi DV, Tuan TL, et al. (2003) Mechanisms of hypoxic regulation of plasminogen activator inhibitor-1 gene expression in keloid fibroblasts. J Invest Dermatol 121: 1005–1012. 58. Bi YM, Ehirchiou D, Kilts TM, Inkson CA, Embree MC, et al. (2007) Identification of tendon stem/progenitor cells and the role of the extracellular matrix in their niche. Nat Med 13: 1219–1227. 59. Shi S, Gronthos S, Chen S, Reddi A, Counter CM, et al. (2002) Bone formation by human postnatal bone marrow stromal stem cells is enhanced by telomerase expression. Nat Biotech 20: 587–591. 60. You S, Moon JH, Kim TK, Kim SC, Kim JW, et al. (2004) Cellular characteristics of primary and immortal canine embryonic fibroblast cells. Exp Mol Med 36: 325–335. 61. Cai S, Liu Y, Shu XZ, Prestwich GD (2005) Injectable glycosaminoglycan hydrogels for controlled release of human basic fibroblast growth factor. Biomaterials 26: 6054–6067. 62. Pike DB, Cai S, Pomraning KR, Firpo MA, Fisher RJ, et al. (2006) Heparin- regulated release of growth factors in vitro and angiogenic response in vivo to implanted hyaluronan hydrogels containing VEGF and bFGF. Biomaterials 27: 5242–5251. 63. Yamaza T, Miura Y, Bi Y, Liu Y, Akiyama K, et al. (2008) Pharmacological stem cell based intervention as a new approach to osteoporosis treatment in rodents. PLoS One 3: 1–9. 64. De Coppi P, Pozzobon M, Piccoli M, Gazzola MV, Boldrin L, et al. (2006) Isolation of mesenchymal stem cells from human vermiform appendix. J Surg Res 135: 85–91. Niche-Driven Overgrowth of KPC 65. Gang EJ, Bosnakovski D, Figueiredo CA, Visser JW, Perlingeiro CR (2007) SSEA-4 identifies mesenchymal stem cells from bone marrow. Blood 109: 1743–1751. 66. Beltrami AP, Cesselli D, Bergamin N, Marcon P, Rigo S, et al. (2007) Multipotent cells can be generated in vitro from several adult human organs (heart, liver, and bone marrow). Blood 110: 3438–3446. 67. Kimura A, Naka T, Kishimoto T (2007) IL-6-dependent and –independent pathways in the development of interleukin 10-producing T helper cells. Proc Natl Acad Sci USA 104: 12099–12104. 68. McGeachy MJ, Bak-Jensen KS, Chen Y, Tato CM, Blumenschein W, et al. (2007) TGF-b and IL-6 drive the production of IL-17 and IL-10 by T cells and restrain TH-17 cell-mediated pathology. Nat Immunol 8: 1390–1397. 69. Zhou L, Ivanov II, Spolski R, Min R, Shenderov K, et al. (2007) IL-6 programs TH-17 cell differentiation by promoting sequential engagement of the IL-21 and IL-23 pathways. Nat Immunol 8: 967–974. 70. MacDonald HR (1984) Phenotypic and functional characteristics of ‘T-like’ cells in nude mice. Exp Cell Biol 52: 2–6. 71. Izadpanah R, Trygg C, Patel B, Kriedt C, Dufour J, et al. (2006) Biologic properties of mesenchymal stem cells derived from bone marrow and adipose tissue. J Cell Biochem 99: 1285–1297. 72. da Silva ML, Chagastelles PC, Nardi NB (2006) Mesenchymal stem cells reside in virtually all post-natal organs and tissues. J Cell Sci 119: 2204–2213. 73. Moon J-H, Kwak SS, Park G, Jung H-Y, Yoon BS, et al. (2008) Isolation and characterization of multipotent human keloid-derived mesenchymal-loke stem cells. Stem Cell Dev 17: 1–12. 74. Boyle M, Wong C, Rocha M, Jones DL (2007) Decline in self-renewal factors contributes to aging of the stem cell niche in the Drosophila testis. Cell Stem Cell 1: 470–478. 75. Pan L, Chen S, Weng C, Call G, Zhu D, et al. (2007) Stem cell aging is controlled both intrinsically and extrinsically in the Drosophila ovary. Cell Stem Cell 1: 458–469. 76. Spaeth E, Klopp A, Dembinski J, Andreeff M, Marini F (2008) Inflammation and tumor microenvironments: defining the migratory itinerary of mesenchymal stem cells. Gene Ther 10: 730–738. 77. Coffelt SB, Marini FC, Watson K, Zwezdaryk KJ, Dembinski JL, et al. (2009) The pro-inflammatory peptide LL-37 promotes ovarian tumor progression through recruitment of multipotent mesenchymal stromal cells. Proc Natl Acad Sci USA 106: 3806–3811. 78. Karnoub AE, Dash AB, Vo AP, Sullivan A, Brooks MW, et al. (2007) Mesenchymal stem cells within tumour stroma promote breast cancer metastasis. Nature 449: 557–563. 79. Mishra PJ, Mishra PJ, Humeniuk R, Medina DJ, Alexe G, et al. (2008) Carcinoma-associated fibroblast-like differentiation of human mesenchymal stem cells. Cancer Res 68: 4331–4339. 80. Spaeth EL, Dembinski JL, Sasser AK, Watson K, Klopp A, et al. (2009) Mesenchymal stem cell transition to tumor-associated fibroblasts contributes to fibrovascular network expansion and tumor progression. PLoS One 4: e4992. 81. Momcilovic´ M, Miljkovic´ Z, Popadic´ D, Markovic´ M, Savic´ E, et al. (2008) Methylprednisolone inhibits interleukin-17 and interferon-gamma expression by both naive and primed T cells. BMC Immunol 9: 47. PLoS ONE | www.plosone.org 16 November 2009 | Volume 4 | Issue 11 | e7798