CCDC3 Inhibits The Proliferation Of Keratinocytes By Downregulating TNF-α/NF-κB Signaling

Objective:To investigate the impact of CCDC3 on keratinocyte proliferation and its potential role in the pathogenesis of psoriasis.Methods:This study utilized gene expression data from psoriasis patients in the GEO database to construct psoriasis-related modules using WGCNA,through which the negative regulator CCDC3 was identified.The expression levels of CCDC3 were measured in the lesions of psoriasis patients and imiquimod-induced psoriatic mice.Additionally,HaCaT cells were stimulated with psoriasis-related inflammatory cytokines(TNF-α,IL-17A,IL-22,IFN-γ)to explore the underlying mechanism of CCDC3 downregulation in psoriatic lesions.Furthermore,a CCDC3 overexpressing HaCaT cell model was developed to investigate the effect of CCDC3 on HaCaT cell proliferation and explore the relevant signaling pathways.Results:1.The results of WGCNA analysis indicated that the brown module exhibited the strongest association with psoriasis,as it contained genes related to psoriasis-related inflammatory factors,including TNF-α,IL-17A,IL-22,and IFN-γ.Notably,CCDC3 was identified as a key gene within the brown module and was found to be down-regulated in psoriasis lesions.2.The downregulation of CCDC3 in psoriasis lesions was found to be mediated by psoriasis-related inflammatory factors.Both CCDC3 mRNA and protein expression levels were significantly reduced in psoriatic lesions compared to controls.Similarly,a murine model of cutaneous phenotype induced by imiquimod,which serves as an acute model of human psoriasis,demonstrated a similar downregulation of CCDC3 expression.Unfortunately,efforts to produce recombinant murine CCDC3 protein were unsuccessful,and no commercial murine CCDC3 was available for use.Therefore,attempts to replenish murine CCDC3 in the imiquimod model were unable to proceed.In vitro experiments using HaCaT cells demonstrated that psoriasis-related inflammatory cytokines,including IL-22 and TNF-α,were capable of repressing the expression of CCDC3,further supporting the hypothesis that CCDC3 downregulation in psoriasis is mediated by inflammatory factors.3.The results indicate that CCDC3 functions as a potent inhibitor of HaCaT cell proliferation.Specifically,CCDC3 inhibits the proliferation of HaCaT cells.Moreover,HaCaT cells overexpressing CCDC3 displayed a significant reduction in proliferation activity compared to control cells.Furthermore,the introduction of exogenous recombinant CCDC3 at a concentration of 300 ng/mL or higher was found to inhibit HaCaT cell proliferation.Additionally,CCDC3 was found to weaken the proliferative effect induced by psoriasis-related cytokines.4.Transcriptome sequencing analysis revealed that the function of CCDC3 in HaCaT cells is closely linked with the TNF signaling pathway.Moreover,overexpression of CCDC3 was observed to suppress the transcription of TNF-α.Furthermore,it was discovered that CCDC3 inhibited the proliferation of keratinocytes by downregulating the TNF-α/NF-κB signaling pathway.Conclusion:In summary,our findings suggest that TNF-α can decrease the expression of CCDC3 in keratinocytes,while CCDC3 can inhibit the pro-proliferative effect of TNF-αby suppressing the TNF-α/NF-κB pathway.These results highlight the important role of CCDC3 as a negative regulator of inflammation and its potential therapeutic value in treating psoriasis by inhibiting the pathological proliferation of keratinocytes.