ZC3H13 Accelerates Keloid Formation by Mediating N6-methyladenosine Modification of HIPK2.

Keloids are fibroproliferative skin disorders caused by the improper healing of wounded skin. A growing body of evidence suggests the involvement of N6-Methyladenosine (m6A) modification in various bioprocesses; however, its role in keloid formation has not yet been investigated. The aim of this study was to determine the effect of the m6A regulator zinc finger CCCH domain containing protein 13 (ZC3H13) on the pathogenesis of keloid formation. ZC3H13 and homeodomain-interacting protein kinase 2 (HIPK2) expression was evaluated in healthy skin and keloid tissues, as well as in human dermal fibroblasts and human keloid fibroblasts (HKF), using qRT-PCR and western blotting. The effects of ZC3H13 overexpression and knockdown on the cell function of HKFs were assessed using CCK8, transwell, and flow cytometry. Furthermore, the influence of ZC3H13 on HIPK2 m6A modification was assessed using MeRIP-qPCR and mRNA stability assays. Both ZC3H13 expression and m6A RNA methylation were upregulated in keloid tissues and HKFs. Silencing of ZC3H13 inhibited proliferation and migration, while enhancing apoptosis in HKFs, whereas overexpression had the opposite effect. Furthermore, HIPK2 levels were high in keloid tissues and HKFs, and a positive correlation was observed between ZC3H13 and HIPK2. In HKFs, ZC3H13 overexpression elevated the m6A levels of HIPK2 mRNA and reduced the rate of HIPK2 mRNA degradation. Mechanically, ZC3H13-induced m6A modifications significantly improved HIPK2 mRNA stability. Collectively, ZC3H13 accelerated keloid formation by mediating the m6A modification of HIPK2 mRNA and maintaining its stability.

RBM15-Mediated m6A Modification of K17 Affects Keratinocytes Response to IL-17A Stimulation in Psoriasis.

OBJECTIVE: Psoriasis is characterized by excessive proliferation and abnormal differentiation of epidermal keratinocytes. This study aimed to reveal the function and mechanism of a N6-methyladenosine (m6A) methyltransferase RNA-binding motif protein 15 (RBM15) in IL-17A-induced keratinocytes. METHODS: A immortalized keratinocyte cell line HaCaT was used to undergo the IL-17A stimulation. The mRNA levels were detected by qRT-PCR, whereas the protein levels were measured by western blotting. The change of keratinocytes proliferation was determined using CCK8 and EdU assays, and the inflammation factors (IL-8 and TNF-α) in keratinocytes were analyzed by qRT-PCR. The m6A modification of Keratin 17 (K17) was confirmed by MeRIP and mRNA stability assays. RESULTS: The levels of RBM15 and K17 in skin samples from patients with psoriasis and IL-17A-induced keratinocytes were upregulated, and showed the positive correlation. Silencing RBM15 suppressed viability, proliferation, and inflammation of keratinocytes that were enhanced by IL-17A stimulation. Moreover, RBM15 knockdown reduced the stability of K17 mRNA via m6A modification method. Since K17 is modified by RBM15, its overexpression relieved the effects of RBM15 knockdown on keratinocytes under IL-17A stimulation. CONCLUSION: This study revealed that RBM15 knockdown suppressed proliferation and inflammation by mediating m6A modification of K17 to reduce K17 stability in IL-17A-induced keratinocytes. Our findings may provide novel idea for improving the treatment of psoriasis.

miR-767-3p suppresses melanoma progression by inhibiting ASF1B expression.

BACKGROUND: Melanoma, the type of skin cancer considered as most malignant, and known to be linked with a high incidence as well as high mortality rate. Although the dysregulation of ASF1B and miR-767-3p expression is involved in the progression of various cancers, their biological function in melanoma remains unclear. METHODS: Real-time qPCR was the primary source for determining the levels of ASF1B and miR-767-3p in melanoma. For the validation of association among miR-767-3p and ASF1B, luciferase activity assay was used. Quantification of cell apoptosis, proliferation, migration and viability in melanoma cells were carried out by flow cytometry, BrdU, transwell assays, and CCK-8, respectively. Further evaluation of tumor growth was achieved by xenograft in vivo. RESULTS: Results showed an increased expression of ASF1B while declined expression of miR-767-3p in melanoma. ASF1B knockdown repressed cell migration, viability, proliferation, and tumor growth whereas boosted apoptosis in A375 as well as in A875 melanoma cells. Moreover, miR-767-3p attenuated the migration and proliferation of melanoma cells and encouraged cell apoptosis by reducing ASF1B levels. CONCLUSION: In this study, miR-767-3p was shown to inhibit ASF1B which will attenuate melanoma tumorigenesis, and by this it can be a potential new effective biomarker for the treatment of melanoma.

MicroRNA-520d-3p suppresses melanoma cells proliferation by inhibiting the anti-silencing function 1B histone chaperone.

As the most common and aggressive malignant form of skin cancer, melanoma has a poor prognosis in its late stage. MicroRNA (miR)-520d-3p has been reported as a key modulator that regulates the development of different types of cancer, but its role in melanoma remains unclear. The purpose of this study was to investigate the role and mechanism of miR-520d-3p in melanoma. The expression of anti-silencing function 1B histone chaperone (ASF1B) and miR-520d-3p in melanoma tissues and cells was detected by reverse transcription-quantitative polymerase chain reaction. The interaction between ASF1B and miR-520d-3p was verified by luciferase activity detection. Cell counting kit-8, bromodeoxyuridine, fluorescein isothiocyanate, and cell adhesion assays were performed to detect cell viability, proliferation, apoptosis, and adhesion in melanoma cells. ASF1B expression was evidently increased, whereas miR-520d-3p level was downregulated in melanoma tissues and cells. Overexpression of ASF1B enhanced cell growth and adhesion and hampered cell apoptosis in melanoma cells. Furthermore, miR-520d-3p suppressed the tumorigenic effects of melanoma cells. Moreover, miR-520d-3p suppressed the expression of ASF1B to suppress melanoma tumorigenesis. In conclusion, we have found out that miR-520d-3p suppressed melanoma tumorigenesis by inhibiting ASF1B, which could be a promising target for melanoma therapy.