The Functional And Mechanism Role Of ARMC8 In The Development Of Cutaneous Squamous Cell Carcinoma

BackgroundCutaneous squamous cell carcinoma(cSCC)is the second highest incidence of skin malignancies.The main causes are immunosuppression,excessive exposure to sunlight,and long-term sunlight(mainly ultraviolet B,UVB)is the most dangerous environmental factor.Squamous cell carcinoma has a high degree of malignancy,the key factors affecting cSCC metastasis are tumor thickness(>2.0mm),tumor location,immunosuppression,and tumor size.MicroRNA(miRNA)is a type of non-coding single-stranded small-molecule RNA with a length of about 19-25 bases encoded by an endogenous gene.It recognizes target mRNAs through complementary base pairing to exert post-transcriptional regulation.Previous research by our research group showed that a half erythema dose(30mJ/cm2)UVB irradiation can cause the up-regulation of miR-664 expression in HaCaT cells,and miR-664 can promote malignant behavior of cSCC.Based on target gene prediction and qPCR verification,this study ARMC8 may be an important downstream molecule for miR-664 to play an oncogene role in cSCC.Through in vivo and in vitro levels,it is planned to facilitate elaborating the mechanism that ARMC8 plays a regulatory role in skin squamous cell carcinoma.Methods①RT-qPCR and western blot were used to detect the expression of ARMC8 in cSCC cell lines(HSC-1 and HSC-5 cells)transfected with miR-664(NC-mimic,mimic,NC-inhibitor,inhibitor);②The expression levels of ARMC8 in HaCaT,A431,HSC-1,and HSC-5 cells were detected by RT-qPCR and western blot;③The targeting relationship between miR-664 and ARMC8 was verified by dual luciferase report experiment;④ CCK-8 assay was used to detect changes in the viability of HSC-1 and HSC-5 cells after the silence or overexpression of ARMC8;⑤Transwell assay was used to detect changes in the migration and invasion ability of HSC-1 and HSC-5 cells after silencing or over-expressing ARMC8;⑥Clone formation assay was performed to detect the changes in the proliferation ability of HSC-1 and HSC-5 cells after the silence or overexpression of ARMC8;⑦The tumorigenesis ability of HSC-5 cells after silencing or over-expressing ARMC8 was detected by subcutaneous tumor formation in nude mice;⑧ The changes of EMT markers in HSC-5 cells after silencing or over-expressing ARMC8 were detected by RT-qPCR,western blot and immunofluorescence.Results①ARMC8 is a downstream target gene of miR-664;②ARMC8 is significantly down-regulated in cSCC pathological sections and cSCC cell lines;③Silencing ARMC8 enhances the malignant behavior of cutaneous squamous cell carcinoma cells,such as cell proliferation,in vitro migration and invasion ability,and tumorigenic capacity in vivo;④ Overexpression of ARMC8 inhibits the malignant behavior of cutaneous squamous cell carcinoma cells;⑤ARMC8 inhibits cutaneous squamous cell carcinoma cells’ EMT.ConclusionARMC8 which is one of the target genes of miR-664 acts as a tumor suppressor gene in skin squamous cell carcinoma by inhibiting epithelial-mesenchymal...