Transcription Factor ZNF22 Regulates Blood-tumor Barrier Permeability By Interacting With HDAC3 Protein

Objective: The main objective of this study was to investigate the role of zinc finger protein transcription factor ZNF22(Homo sapiens zinc finger protein 22,ZNF22)and histone deacetylase3(HDAC3)in regulating the blood tumor barrier(BTB).The role of histone deacetylase 3 and HDAC3 in regulating the increased permeability of the blood tumor barrier(BTB)and some possible molecular mechanisms associated with this role have been investigated.In primary brain tumors,such as glioblastoma,and in brain metastases from cancers of other organs(e.g.,lung cancer,breast cancer,and melanoma),the blood-brain barrier around the capillaries of the brain parenchyma is altered,referred to as the BTB.Although the permeability of the barrier is elevated,this alteration retains the ability to limit the entry of most therapeutic agents into the intracranial tumor,and investigating how to overcome this limitation is critical to improving treatment outcomes and patient quality of life.Research to overcome this limitation is key to improving treatment outcomes and patient quality of life.Despite the long and intensive research on primary tumors in the brain,there has been limited attention and research on BTB.However,in the limited studies,BTB still provides an effective molecular target to improve cancer therapeutic measures.Transcription factors(TGFs)are important proteins involved in the regulation of gene expression in living organisms,which can affect cell growth,differentiation,and function.In recent years,with the continuous development of biological technology,more and more studies have demonstrated the important regulatory role of transcription factors in the formation,maintenance and drug delivery of BTB,and transcription factors are important targets for the treatment of glioma.ZNF22,which is localized at 10q11.2,is a classical transcription factor.In our preliminary bioinformatics JASPAR,Human TFDB and KEGG analyses,we found that ZNF22 was negatively correlated with the expression of gap junctions,and ZNF22 may be a tight junction protein(TJ)-associated protein ZO-1,Occludin and Claudin-5transcription factor,which was further investigated in this study.Further studies were conducted to fully understand the role of ZNF22 in regulating BTB permeability and to translate these findings into effective treatments for patients.Protein interactions refer to the process of binding two or more proteins designed to perform their biochemical functions.Protein interactions play an important role in the regulation of transcription,and many experiments have demonstrated that protein interactions can perform transcriptional regulatory functions and directly affect the transcriptional activity of transcription factors.HDAC is an enzyme that removes lysine residues from the NH2 terminus of core histones acetylase,which makes the chromatin structure more closed and thus inhibits gene expression.It has been suggested that increased HDAC activity causes down-regulation of tight junction protein expression,while the use of HDAC inhibitor(HDACi)can up-regulate the expression of tight junction related proteins,and we found that ZNF22 and HDAC3 have a high binding potential through the protein interoperation software STRING et al.Methods: The expression of ZNF22 and HDAC3 in BTB glioma-exposed endothelial cells(GECs)was detected by q RT-PCR and western blot.ZNF22,HDAC3 and ZNF22+HDAC3 expression silencing GECs were established.Expression levels of ZO-1,Occludin and Claudin-5 were examined using real-time fluorescence quantitative PCR and western blot.The expression and distribution of ZO-1,Occludin and Claudin-5 were further examined by immunofluorescence,and BTB permeability was measured by TEER and HRP flux assay.The direct interaction of ZNF22 with the promoters of ZO-1,Occludin and Claudin-5 was analysed by Ch IP and Ch IP-q PCR assay.Results: In the present study,GECs expressed higher levels of the zinc finger protein transcription factor ZNF22 and HDAC3 than endothelial cells.We subsequently confirmed that silencing HDAC3 or ZNF22 resulted in a reduced BTB permeability.By bioinformatics analysis,chromatin immunoprecipitation(Ch IP)and luciferase assay,we found that ZNF22 has a target binding relationship with ZO-1,Occludin and Claudin-5promoter regions and negatively regulates the expression of ZO-1,Occludin and Claudin-5.In addition,we found that HDAC3,a co-transcriptional repressor with histone deacetylase activity,could interact with ZNF22 to impede the expression of TJ-related proteins,thus further promoting the permeability of BTB.Conclusion: ZNF22 and HDAC3 were highly expressed in GECs,and high expression of ZNF22 and HDAC3 increased BTB permeability.ZNF22 as a transcription factor combined with HDAC3 to regulate the expression of TJ-related proteins was associated with increased BTB permeability.These results may provide new strategies and targets for chemotherapy of gliomas and intracranial infections.