The Mechanism Of Low Expression Of ILF2 Down-regulated CENPE To Inhibit The Proliferation Of Breast Cancer Cells

Background:In recent years,with the change of lifestyle,the gradually increasing pressure of working and life,breast cancer has become the leading cause of death of women with malignant tumors.In the past,clinicians established TNM staging of tumors based on their size,extent of invasion,lymph node metastases or distant metastases,etc.to help physicians learn more about the tumor and thus help determine the treatment respectively.According to different tumor staging,the majority treatment of patients in clinical still based on sugery,assistant with radiotherapy and chemotherapy.However,due to the lack of pertinent therapeutic targets,the effect of comprehensive treatment has not met the expectation.Therefore,it is still an important task for clinical research to further explore the target of breast cancer therapy.In recent years,new biomarkers such as cell cycle regulators,oncogenes and tumor suppressor genes involved in the process and development of malignant tumors have gradually become the research hotspot.The transcription factor Interleukin enhancer binding factor 2?ILF2?,also known as nuclear factor 45?NF45?,is encoded by genes located on human chromosome 1?1q11-qter and 1p11-p12?^[1].ILF2-encoded protein,a subunit of NF-AT?a nuclear factor of activated T cells?,is a sequence-specific DNA-binding protein that regulates cell growth by inhibiting mRNA stability and is also well established one of the factors that cause cancer.It has been reported in the literature that ILF2 can promote the progress of many types of cancer^[2].For example,ILF2 is overexpressed in lymphomas,leukemias,gliomas,cervical and esophageal cancers and may lead to uncontrolled proliferation of cancer cells^[3-7].More literature has demonstrated that depletion of ILF2 in pancreatic ductal adenocarcinomas reduces cyclin E and increases the level of nuclear antigen?PCNA?,and an increased expression of ILF2 in tumor tissue may suggest a poor prognosis or it predict a poor type of clinical pathology^[2].However,up to now,there has been no report on ILF2 in breast cancer.This paper aims to study the function of ILF2 in breast cancer cells and related molecular mechanisms.Methods:First,the existing tumor-related gene research database?oncomine database?was used to query whether ILF2 is expressed in breast cancer;the expression level of ILF2 in different breast cancer cell lines was tested by experiments;then selected a cell line for the experiment.The expression of ILF2 in breast cancer cells was down-regulated by siRNA and the expression of ILF2 was verified by PCR and Western Blot.The results of plate clony assay and MTT assay showed whether any change can observed in proliferation of breast cancer cells after ILF2 down-regulation.After knockdown,whether the ability of breast cancer cells to migrate was different.Then,we found that down-regulation of IL-2 in breast cancer cells may affect cell proliferation through CENPE.Therefore,we validated the expression of CENPE in different breast cancer cell lines,down-regulated the expression of CENPE in breast cancer cells by siRNA,and verified the expression of CENPE by PCR and Western Blot.The results of plate clony assay and MTT assay after CENPE down-regulated in breast cancer cell test the proliferation ability;scratch test used to detect migration ability after knockdown CENPE in breast cancer cells.Results:Through RNA level and protein level test,we found that ILF2 was highly expressed and varied in different breast cancer cell lines.Using siRNA to down-regulate ILF2 in breast cancer cell line MDA-MB-231,it can effectively inhibit ILF2 expression in breast cancer cells.At the same time ILF2 down-regulation will also affect the expression of CENPE,and its expression decreased.The plate clony experiment and MTT assay showed that the proliferation of breast cancer cells was significantly inhibited after ILF2 down-regulation.Scratch test results showed that down-regulated ILF2 in breast cancer cell the migration ability was not obviously observed.By RNA level and protein level test we found that,CENPE expression in different cell lines of breast cancer is different.Knockdown CENPE in breast cancer cell line MDA-MB-231by siRNA showed that siRNA could effectively inhibit the expression of CENPE in breast cancer cells.Plate clony assay and MTT experiment showed that the down-regulation of CENPE can effectively inhibit the proliferation of breast cancer cells.Scratch test results show that migration ability after CENPE down-regulation of breast cancer cell has been enhanced.Conclusion:This paper through a series of experiments confirmed that,ILF2 is overexpressed in breast cancer cells.The proliferation of breast cancer cells decreased significantly after ILF2 was down-regulated,but the effect on migration ability was not obviously observed.The decrease expression of CENPE in breast cancer cells after knockdown ILF2 indicates that the low expression of ILF2 affects the proliferation of breast cancer cells through the down-regulation of CENPE.