Bulge- and Basal Layer-Specific Expression of Fibroblast Growth Factor-13 (FHF-2) in Mouse Skin

A variety of polypeptide growth factors are involved in the dynamic maintenance of the skin and hair. Here, we demonstrate the presence of high levels of fibroblast growth factor (FGF)-13 in the bulge region of hair follicles. Using real-time PCR, we found that expression of FGF-13 mRNA is comparable to, or higher than, that of other FGF known to regulate hair growth and wound healing. To gain additional insight into the function of FGF-13, we evaluated its distribution using in situ hybridization and immunohistochemical staining. Unlike other FGF, the distribution of FGF-13 mRNA and protein in adult mice was mainly restricted to cells in the bulge region of hair follicles, although lower levels were detected with less frequency in keratinocytes in the basal layer of the epidermis. FGF-13 protein was detectable in the bulge region throughout the hair growth cycle, but its distribution was especially wide during telogen and early anagen. During hair follicle morphogenesis in newborn mice, FGF-13 protein was first detected in the bulge region and basal layer keratinocytes 3 d after birth. These findings suggest that FGF-13 may play a role in regulating the function of cells in the bulge region and basal layer of the epidermis

EWS/ETS Regulates the Expression of the Dickkopf Family in Ewing Family Tumor Cells

BACKGROUND: The Dickkopf (DKK) family comprises a set of proteins that function as regulators of Wnt/beta-catenin signaling and has a crucial role in development. Recent studies have revealed the involvement of this family in tumorigenesis, however their role in tumorigenesis is still remained unclear. METHODOLOGY/PRINCIPAL FINDINGS: We found increased expression of DKK2 but decreased expression of DKK1 in Ewing family tumor (EFT) cells. We showed that EFT-specific EWS/ETS fusion proteins enhance the DKK2 promoter activity, but not DKK1 promoter activity, via ets binding sites (EBSs) in the 5' upstream region. EWS/ETS-mediated transactivation of the promoter was suppressed by the deletion and mutation of EBSs located upstream of the DKK2 gene. Interestingly, the inducible expression of EWS/ETS resulted in the strong induction of DKK2 expression and inhibition of DKK1 expression in human primary mesenchymal progenitor cells that are thought to be a candidate of cell origin of EFT. In addition, using an EFT cell line SK-ES1 cells, we also demonstrated that the expression of DKK1 and DKK2 is mutually exclusive, and the ectopic expression of DKK1, but not DKK2, resulted in the suppression of tumor growth in immuno-deficient mice. CONCLUSIONS/SIGNIFICANCE: Our results suggested that DKK2 could not functionally substitute for DKK1 tumor-suppressive effect in EFT. Given the mutually exclusive expression of DKK1 and DKK2, EWS/ETS regulates the transcription of the DKK family, and the EWS/ETS-mediated DKK2 up-regulation could affect the tumorigenicity of EFT in an indirect manner

Highly sulfated hyaluronic acid maintains human induced pluripotent stem cells under feeder-free and bFGF-free conditions

Human induced pluripotent stem (hiPS) cells are attracting attention as a tool for regenerative medicine. However, several problems need to be overcome for their widespread and safe use, for example, the high cost of maintaining hiPS cells and the possibility of xenogeneic cell contamination in hiPS cell cultures. One of the main contributors to the high cost of maintaining hiPS cells is basic fibroblast growth factor (bFGF), which is essential for such cultures. Xenogeneic contamination can occur because of the use of mouse-derived feeder cells to culture hiPS cells. To overcome the problems of cell culture cost and xenogeneic contamination, we have developed a novel culture method in which the undifferentiated state and pluripotency of hiPS cells can be maintained under feeder-free and bFGF-free conditions. Our new approach involves the addition to the culture medium of highly sulfated hyaluronic acid (HA-HS), in which the hydroxyl groups of d-glucuronic acid (GlcA) and N-acetyl-d-glucosamine (GlcNAc) are chemically sulfated. HA-HS promotes bFGF signaling and maintains the undifferentiated state and pluripotency of hiPS cells under feeder-free and bFGF-free conditions. By contrast, non-sulfated hyaluronic acid and low sulfated hyaluronic acid do not maintain the undifferentiated state and pluripotency of hiPS cells. These results indicate that the maintenance of hiPS cells under feeder-free and bFGF-free conditions is an HA-HS specific effect. This study is the first to demonstrate the effects of sulfated hyaluronic acid on mammalian pluripotent stem cells, and provides a novel method for maintaining hiPS cells using HA-HS

Comparison of CD163+ Macrophages and CD206+ Cells in Lesional Skin of CD30+ Lymphoproliferative Disorders of Lymphomatoid Papulosis and Primary Cutaneous Anaplastic Large-cell Lymphoma.

CD30+ lymphoproliferative disorders represent a spectrum of diseases from lymphomatoid papulosis (LyP) to primary cutaneous anaplastic large-cell lymphoma (PCALCL) (1, 2). LyP is characterized by recurrent papulonodular lesions, which undergo spontaneous regression (1, 2). Survival is unaffected by LyP, but patients are at risk of a second cutaneous or lymphoid malignancy (1). PCALCL has a favourable prognosis with a 5-year survival rate between 76% and 96%. In this report, we used immunohistochemical (IHC) staining of LyP type A and PCALCL specimens to examine for macrophage markers as well as dendritic cell (DC)-specific markers and their functional markers

High-sulfated hyaluronic acid ameliorates radiation-induced intestinal damage without blood anticoagulation

Purpose: Many growth factors, such as fibroblast growth factors (FGFs), are useful for the treatment or prevention of radiation damage after radiotherapy. Although heparin can be supplemented to increase the therapeutic effects of FGFs, it possesses strong anticoagulant effects, which limit its potential for clinical use. Therefore, chemically-sulfated hyaluronic acid (HA) was developed as a safe alternative to heparin. This study examined the involvement of sulfated HA in the radioprotective and anticoagulant effects.Methods and Materials: FGF1 was administered intraperitoneally to BALB/c mice with sulfated HA 24 h before or after total body irradiation (TBI) with γ-rays. Several radioprotective effects were examined in the jejunum. The blood coagulation time in the presence of sulfated HA was measured using murine whole blood. Results: FGF1 with high-sulfated HA (HA-HS) exhibited almost the same level of in vitro mitogenic activity as heparin, whereas FGF1 with HA or low-sulfated HA (HA-LS) exhibited almost no mitogenic activity. Furthermore, HA-HS had high binding capability with FGF1. FGF1 with HA-HS significantly promoted crypt survival to the same level as heparin after TBI and reduced radiation-induced apoptosis in crypt cells. Moreover, pre-treatment of HA-HS without FGF1 also increased crypt survival and reduced apoptosis. Crypt survival with FGF1 in the presence of HA depended on the extent of sulfation of HA. Moreover, the blood anticoagulant effects of sulfated HA were weaker than those of heparin. As sulfated HA did not promote the reactivity of antithrombin III (AT-III) to thrombin, it did not increase anti-coagulative effects to the same extent as heparin. Conclusion: This study suggested that HA-HS promotes the radioprotective effects of FGF1 without anticoagulant effects. HA-HS has great potential for practical use to promote tissue regeneration after radiation damage

FGF18 Signaling in the Hair Cycle Resting Phase Determines Radioresistance of Hair Follicles by Arresting Hair Cycling

PurposeTelogen (resting phase) hair follicles (HFs) are more radioresistant than their anagen (growth phase) counterparts. Fibroblast growth factor (FGF) 18 is strongly expressed in telogen HFs to maintain the telogen phase, while several other FGFs exert radioprotective effects. However, the role of FGF18 in the radioresistance of HFs remains unknown. Therefore, this study focused on clarifying the role of FGF18 in the radioresistance of telogen HFs and its potential as a radioprotector.\nMethods and MaterialsBALB/c mice with telogen or plucking-induced anagen HFs were exposed to total body irradiation with γ-rays at 4 to 12 Gy after intraperitoneal treatment with a FGF18 or FGFR inhibitor. A time course analysis was performed histologically and hair growth was observed 14 or 15 days after depilation. Skin specimens were analyzed by DNA microarrays and western blotting.\nResultsTelogen irradiation at 6 Gy resulted in transient cell growth arrest, leading to successful hair growth, whereas anagen irradiation failed to promote hair growth. Telogen irradiation did not induce apoptosis in HFs or reduce hair follicle stem cells, whereas anagen irradiation induced apoptosis and reduced stem cell numbers. The Inhibition of FGF receptor signaling during the telogen phase promoted HF cell proliferation; however, hair failed to grow after irradiation. In contrast, recombinant FGF18 induced transient cell growth arrest after anagen irradiation with enhanced DNA repair, leading to the inhibition of apoptosis, maintenance of hair follicle stem cells, and successful hair growth. Moreover, FGF18 reduced the expression levels of genes promoting G2/M transition as well as the protein expression levels of cyclin B1 and cdc2 in skin, and induced G2/M arrest in the keratinocyte cell line HaCaT.\nConclusionThese results suggest that FGF18 signaling mediates radioresistance in telogen HFs by arresting the cell cycle, and that FGF18 has potential as a radioprotector for radiation-induced alopecia