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Summary: Melanoma is the deadliest form of skin cancer, affecting men more frequently and severely than women. Although recent studies suggest that differences in activity of the androgen receptor (AR) underlie the observed sex bias, little is known about AR activity in melanoma. Here we show that AR and EGR1 bind to the long non-coding RNA SLNCR and increase melanoma proliferation through coordinated transcriptional regulation of several growth-regulatory genes. ChIP-seq reveals that ligand-free AR is enriched on SLNCR-regulated melanoma genes and that AR genomic occupancy significantly overlaps with EGR1 at consensus EGR1 binding sites. We present a model in which SLNCR recruits AR to EGR1-bound genomic loci and switches EGR1-mediated transcriptional activation to repression of the tumor suppressor p21Waf1/Cip1. Our data implicate the regulatory triad of SLNCR, AR, and EGR1 in promoting oncogenesis and may help explain why men have a higher incidence of and more rapidly progressive melanomas compared with women. : Long non-coding RNA function can be understood by defining their interacting proteins. Schmidt et al. demonstrate that the melanoma lncRNA SLNCR binds to AR and complexes with different transcription factors to mediate invasion or proliferation. Thus, lncRNAs regulate distinct transcriptional programs based on specific protein interactions. Keywords: long non-coding RNA, linc00673, melanoma, proliferation, EGR1, androgen receptor, metastasis, CDKN1A, p21, Waf1/Cip1

The ability to efficiently transduce hematopoietic stem cells (HSC) represents a powerful methodology by which to study the role of specific genes on HSC function, as well as to broaden the potential of gene therapy for hematopoietic related diseases. While retroviruses have been used extensively to transduce a variety of cell types, HIV-derived lentiviruses prove superior for transduction of quiescent HSC due to their ability to infect non-dividing cells. Quality of lentiviral supernatants and starting cells are vital to obtain reproducible consistent results, and therefore, here we describe the production of concentrated lentiviral preparations, the purification of HSC from total mouse bone marrow, and their transduction to obtain long-term HSC engraftment with persistent gene transfer and expression of the desired transgene.

Background: Anaplastic thyroid cancer (ATC) is one of the most lethal human malignancies. Its rapid onset and resistance to conventional therapeutics contribute to a mean survival of six months after diagnosis and make the identification of thyroid-cancer-initiating cells increasingly important., Methodology/principal Findings: In prior studies of ATC cell lines, CD133(+) cells exhibited stem-cell-like features such as high proliferation, self-renewal and colony-forming ability in vitro. Here we show that transplantation of CD133(+) cells, but not CD133(-) cells, into immunodeficient NOD/SCID mice is sufficient to induce growth of tumors in vivo. We also describe how the proportion of ATC cells that are CD133(+) increases dramatically over three months of culture, from 7% to more than 80% of the total. This CD133(+) cell pool can be further separated by flow cytometry into two distinct populations: CD133(+/high) and CD133(+/low). Although both subsets are capable of long-term tumorigenesis, the rapidly proliferating CD133(+/high) cells are by far the most efficient. They also express high levels of the stem cell antigen Oct4 and the receptor for thyroid stimulating hormone, TSHR. Treating ATC cells with TSH causes a three-fold increase in the numbers of CD133(+) cells and elicits a dose-dependent up-regulation of the expression of TSHR and Oct4 in these cells. More importantly, immunohistochemical analysis of tissue specimens from ATC patients indicates that CD133 is highly expressed on tumor cells but not on neighboring normal thyroid cells., Conclusions/significance: To our knowledge, this is the first report indicating that CD133(+) ATC cells are solely responsible for tumor growth in immunodeficient mice. Our data also give a unique insight into the regulation of CD133 by TSH. These highly tumorigenic CD133(+) cells and the activated TSH signaling pathway may be useful targets for future ATC therapies.

Ongoing advances in stem cell research have opened new avenues for therapy for many human disorders. Until recently, however, thyroid stem cells have been relatively understudied. Here, we review what is known about thyroid stem cells and explore their utility as models of normal and malignant biological development. We also discuss the cellular origin of thyroid cancer stem cells and explore the clinical implications of cancer stem cells in the thyroid gland. Since thyroid cancer is the most common form of endocrine cancer and that thyroid hormone is needed for the growth and metabolism of each cell in the body, understanding the molecular and the cellular aspects of thyroid stem cell biology will ultimately provide insights into mechanisms underlying human disease.

We previously described a new class of conserved, cell adhesive (haptotactic) peptides, termed Haptides, based on sequences first identified in fibrinogen. Here, we describe a new biomaterial, Haptide-coated Collagen, in which the carbodiimide reagent, EDC, was used to covalently couple a Haptide (preC gamma), equivalent to the carboxy terminus of the fibrinogen gamma chain, to a cross-linked sponge composed of bovine collagen type I. The dose response of Haptide bound to collagen on cell attachment response reached a plateau at a concentration of 5-10 mg Haptide/g collagen. The Haptized-collagen was more stable to 1N NaOH, with a degradation half-time (T(1/2)) of 1.7 h, compared to 0.9 h for untreated control. Haptized collagen discs could be loaded with approximately 30% more human dermal fibroblasts or bovine aortic endothelial cells than unmodified collagen discs (p < 0.001). After a proliferation phase, Haptized collagen discs contained approximately 45% more fibroblasts than non-Haptized discs (p < 0.01). Histological analysis following sub-dermal implantation in rats indicated that at day 8, Haptized collagen sponge was less degraded than unmodified collagen sponge, attracted more endogenous fibroblasts with newly deposited collagen, and provoked less inflammatory or other adverse reactions. These results suggest potential clinical applications for Haptized collagen sponge for tissue regeneration, soft tissue augmentation, skin repair, and wound healing., ((c) 2007 Wiley Periodicals, Inc.)