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Fibroblast growth factor (FGF2) is reported to affect the proliferation, differentiation, and survival abilities of stem cells. In this study, we hypothesize that FGF2 might promote the differentiation of hair follicle stem cell (HFSCs) into endothelial cells (ECs), in a manner dependent on STAT5 activation. We first treated human HFSCs with recombinant human FGF2 to determine the involvement of FGF2 in the differentiation of HFSCs. Then the expression of EC-specific markers including von Willebrand factor (vWF), VE-cadherin, CD31, FLT-1, KDR and Tie2 was evaluated using immunofluorescence and flow cytometry, while the expression of HFSC-specific markers such as K15, K19, Lgr5, Sox9 and Lhx2 was determined by flow cytometry. Next, in vitro tube formation was performed to confirm the function of FGF2, and low-density lipoprotein (LDL) uptake by ECs and HFSCs was studied by Dil-acetylated LDL assay. In addition, we transduced FGF2-treated HFSCs with constitutive-active or dominant-negative STAT5A adenovirus vectors. FGF2 up-regulated the expression of EC-specific markers, and promoted the differentiation of HFSCs into ECs, tube formation and LDL uptake. The phosphorylated STAT5 was translocated into the nucleus of HFSCs after FGF2 treatment, but this translocation was blocked by the dominant-negative STAT5A mutant. FGF2 increased the differentiation potential through the activation of STAT5 in vivo. Taken together, we find that FGF2 promotes the differentiation of HFSCs into ECs via activated STAT5, which gives a new perspective on the role of FGF2 in the development of ischemic vascular disease.

BRAF-activated non-coding RNA (BANCR) is a long non-coding RNA (lncRNA) that contributes to the initiation and development of many solid tumors, including melanoma. However, the BANCR functions and downstream mechanisms are largely unknown. In this study, we aim to investigate how BANCR participates in the proliferation and migration of malignant melanoma and elucidate the underlying mechanism in this process. We found that the expression of the BANCR was low in melanocytic nevus and human melanocytes but high in melanoma tissues and cell lines. Knockdown of BANCR inhibited melanoma cell proliferation and invasion, and induced cell apoptosis. The decreased expression of relative marker proteins further demonstrated the inhibitory effect of BANCR siRNA in cell growth and migration. Then, we detected downregulation of microRNA-204 (miR‑204), a suppressor of melanoma growth, in melanoma tissues and cell lines. We identified that miR‑204 was a direct target of BANCR and neurogenic locus notch homolog protein 2 (Notch2) was a direct target of miR‑204. BANCR may promote melanoma cell growth through inhibition of miR‑204, leading to the activation of Notch2 pathway. By tumorigenicity assay in BALB/c nude mice, we further demonstrated that BANCR knockdown inhibited tumor growth in vivo. Our results suggest the BANCR/miR‑204/Notch2 axis mediates melanoma cell proliferation and tumor progression.

Aims The purpose of this study was to explore the precise role and mechanism of p38 inhibiting cutaneous squamous cell carcinoma associated lincRNA (PICSAR) in CSCC. Materials and methods The expression levels of PICSAR, microRNA-125b (miR-125b) and yes-associated protein1 (YAP1) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation, apoptosis and invasion were evaluated by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, transwell assay, respectively. The interaction between miR-125b and PICSAR or YAP1 was predicted by bioinformatics software and confirmed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Western blot was employed to detect the protein expression of YAP1. The mice xenograft model was established to investigate the role of PICSAR in vivo. Key findings PICSAR was upregulated in CSCC tissues and cells. PICSAR knockdown inhibited cell proliferation and invasion and induced apoptosis in CSCC cells. Moreover, miR-125b could directly bind to PICSAR and its inhibition reversed the effect of PICSAR knockdown on proliferation, invasion and apoptosis in CSCC cells. In addition, YAP1 was a direct target of miR-125b and its overexpression attenuated the anti-cancer role of miR-125b in CSCC cells. Furthermore, YAP1 expression was positively regulated by PICSAR and negatively regulated by miR-125b. Besides, interference of PICSAR suppressed tumor growth by upregulating miR-125b and downregulating YAP1. Significance PICSAR knockdown suppressed cell proliferation and invasion and promoted apoptosis in CSCC cells by regulating miR-125b/YAP1 axis, providing new sights for treatment of CSCC.

Long non-coding RNAs (lncRNAs) are defined as non-coding transcripts (>200 nucleotides) that serve important roles in the proliferation and differentiation of stem cells. Hair follicle stem cells (HFTs) have multidirectional differentiation potential and are able to differentiate into skin, hair follicles and sebaceous glands, serving a role in skin wound healing. The aim of the present study was to analyze the regulatory role of lncRNA AK015322 (IncRNA5322) in HFTs and the potential mechanism of IncRNA5322‑mediated differentiation of HFTs. The results demonstrated that lncRNA5322 transfection promoted proliferation and differentiation in HFTs. It was identified that lncRNA5322 transfection upregulated the expression and phosphorylation of phosphoinositide 3‑kinase (PI3K) and protein kinase B (AKT) in HFTs. It was also observed that lncRNA5322 transfection upregulated microRNA (miR)‑21 and miR‑21 agonist (agomir‑21) eliminated lncRNA5322‑induced expression and phosphorylation of PI3K and AKT. The present study also demonstrated that agomir‑21 blocked IncRNA5322‑induced expression and phosphorylation of PI3K and AKT in HFTs. The results indicated that agomir‑21 transfection also suppressed the IncRNA5322‑induced proliferation and differentiation of HFTs. In conclusion, the results of the present study suggest that lncRNA5322 is able to promote the proliferation and differentiation of HFTs by targeting the miR‑21‑mediated PI3K‑AKT signaling pathway in HFTs.

The proliferation and differentiation of hair follicle stem cells (HFSCs) is regulated by several signaling pathways, including BMP and PTEN. Therefore, this study intended to clarify the potential effects of two such regulators, BMP2 and PTEN, on HFSC differentiation. HFSCs were subjected to BMP2, noggin (BMP2 ligand inhibitor), rapamycin (Rapa, autophagy inducer), 3-methyladenine (3-MA, autophagy inhibitor), or shRNA against PTEN. The differentiation of HFSCs was evaluated using oil red O staining and autophagy was assessed using the transmission electron microscope. Then expression of epidermal differentiation marker (K10 and involucrin), adipogenic markers (PPAR-γ2, aP2, perilipin2, and Adipoq), keratinocyte-specific marker (K15), proliferation-related markers (PCNA and Ki67) and autophagy-related factors (Atg5, Atg7, Atg12, Beclin-1 and LC3-II/LC3-I) was examined by RT-qPCR and Western blot analysis. Next, HFSCs were treated with 3-MA, or shRNA against Atg5 or Atg7 to verify the effect of autophagy on differentiation of BMP2-treated HFSCs. Finally, the effect of BMP2 on HFSC differentiation was verified by a mouse wound model. HFSCs overexpressing BMP2 exhibited elevated expression of epidermal differentiation marker, adipogenic markers and autophagy-related factors but inhibited expression of keratinocyte-specific marker and proliferation-related markers. Furthermore, we found that PTEN promoted the differentiation of BMP2-treated HFSCs by inducing autophagy. In vivo experiments further confirmed the roles of BMP2/PTEN on differentiation of HFSCs. Taken together, BMP2 up-regulated PTEN and consequently induced autophagy to facilitate HFSC differentiation.

MicroRNAs (miRNAs) have been widely accepted to play important roles in the regulation of keratinocyte functions. Here, we aimed to further explore the role and underlying mechanism of miR-125b-5p and miR-181b-5p in psoriasis. The expression levels of miR-125b-5p, miR-181b-5p and Akt3 mRNA were detected by qRT-PCR assay. Cell proliferation ability was determined by MTT assay and BrdU incorporation assay. Dual-luciferase reporter assay and RNA Immunoprecipitation assay were used to confirm the targeted interaction between miR-125b-5p or miR-181b-5p and Akt3 in human epidermal keratinocytes (HEKs). The levels of ki-67, Akt3 protein, Akt, p-Akt, mTOR and p-mTOR were measured by Western blot. Our study indicated that miR-125b-5p and miR-181b-5p were downregulated (about 61.3% with miR-125b-5p and 60.4% with miR-181b-5p) and Akt3 was upregulated (about 2.68-fold) in psoriasis. Upregulation of miR-125b-5p or miR-181b-5p resulted in about a 33% or 40% reduction of HEKs proliferation in vitro, while Akt3 overexpression triggered a 1.3-fold enhancement on HEKs proliferation. Akt3 was a direct target of miR-125b-5p or miR-181b-5p. Moreover, HEKs proliferation ability in cotransfection of miR-125b-5p mimics (or miR-181-5p mimics) and vector-Akt3 group was about 2-fold (or 1.98-fold) that in the miR-125b-5p mimics (or miR-181-5p mimics) alone group. Akt/mTOR signaling was involved in miR-125b-5p mimics- or miR-181b-5p mimics-mediated inhibition effect on HEKs proliferation. Our study suggested that the upregulation of miR-125b-5p or miR-181b-5p inhibited HEKs proliferation at least partly by targeting Akt3, providing novel mechanisms of miRNAs involved in psoriasis.