Effect Of BRWD3 On Breast Cancer Cell Spread

Since the end of the 1970 s,the incidence of breast cancer has been on the rise globally.Although it decreased slightly in the 1990 s,it is still threatens women’s health and life.In China,the incidence of breast cancer is still at first place,although the mortality rate has decreased,but it is still an important type of cancer death in women.In the field of clinical intervention and basic research,the researchers have reached a consens us: detection and intervention at its early stage is the most cost-effective choices.Biomarker screening and application have important practical value for the diagnosis and prevention of breast cancer.Previous studies have found that BRWD3 is over-expressed in the plasma of patients with breast cancer,but it only has potential value as a diagnostic and prognostic indicator due to the lack of functional studies in breast cancer.BRWD3 is composed of two types of domains,WD40 and bromodomain(Brd),which are often involved in cellular activities with chromatin modifiers or transcriptional regulators.Other researchers have found that PC3 cells were rounded when BRWD3 was knocked down.To explore the role and mechanism of BRWD3 in the progression of breast cancer,and to analyze whether it can be a diagnostic marker for the occurrence and development of breast cancer,the expression level of BRWD3 was knocked down with RN Ai in breast cancer cell lines.Migration ability was measured with methods of scratch test and transwell invasion assay.Cytoskeleton was exhibited with cellular immunofluorescence.Zebrafish intestinal embryo is an important model for studying cell migration and movement.It can be used to explore whether the target molecule directly affects the cell migration and movement without the interference of disease factors.In this study,zebrafish protointestinal embryo was used as a model.Using morpholino targeting method,the synthesized Brwd3 specific targeting sequence was injected into zebrafish embryos at stage I.The embryos were cultured in embryonic water at 28 C.Before the beginning of the protointestinal embryo(outsourcing 30%)and the end of the protointestinal embryo(tail bud stage),the wild type and the embryos after morpholino injection were taken,RNA was extracted and transferred.Genome sequencing and bioinformatics were used to screen genes related to cytoskeleton and cell movement affected by Brwd3.Subsequently,the related genes screened from the cell movement model were used to reduce BRWD3 level in breast cancer cell lines.Real-time quantitative fluorescence PCR was used to analyze whether these genes were affected,and to explore the mechanism clues of BRWD3 level changes on breast cancer cell proliferation..The results indicated:(1)Spread ability was significantly decreased in both cell lines of MCF-7 and MDA-MB-231,when BRWD3 was knocked down.(2)Pseudopod of MCF-7 was decreased,and morphology of MDA-MB-231 was rounded,after BRWD3 was knocked down.(3)With cellular movement model,we identified many downstream genes including that Enah,Arpc3,Arpc1 a,Vim,Rhoc,Snail,Cd44,Ca9,Stmn1 involved in cell migration and cytoskeleton,such as ENAH、ARPC3、ARPC1A、VIM、RHOC、SNAIL、CD44、CA9、STMN1 were affected when BRWD3 was knocked down.In our previous works,chromatin immunoprecipitation combined with sequencing technology(Ch IP-Seq)have screened that BRWD3 regulating DICER 1 transcription specifically through binding to the promoter region of DICER 1 gene.DIC ER 1 is a key enzyme in the formation of micro RNA,which can regulate the expression of ENAH and affect the reorganization of microfilament cytoskeleto n,affecting cell morphology and invasion and migration ability through affecting the formation of mi RNA-130b-3p and mi RNA-200a-3p.Conclusion: Combined with previous studies and our work,the level of BRWD3 was changed in the MCF-7 and MDA-MB-231,the expression level of genes with microfilament cytoskeleton-related was affected,and the cytoskeleton,morphology and spread of breast cell were affected.This study initially provided clues for the role of BRWD3 in the spread ability of breast cancer,and laid the theoretical foundation for BRWD3 to become a prognostic indicator for breast cancer.