| Objective:Breast cancer is the most common tumor among women in the world.In 2020,the number of new cases of breast cancer has surpassed that of lung cancer,becoming the number one cancer in the world.At present,the treatment of breast cancer is mainly based on surgery,supplemented by radiation therapy,chemotherapy,targeted therapy and other comprehensive therapies.It is also because of the high heterogeneity and easy metastasis and recurrence of breast cancer that the mortality rate of breast cancer remains high every year.Therefore,it is urgent to find new potential targets with more therapeutic effects.As a subunit of the HAUS(the human augmin like complex subunit)protein complex,HAUS5 is involved in maintaining the integrity of the centrosome and the formation of the spindle and microtubules.Therefore,the abnormality of HAUS5 leads to the enlargement of centrosome volume,the fragmentation of microtubules,the reduction of kinetochore fibers,the misalignment of chromosomes and the defect of bipolar spindle function.There are currently few studies on HAUS5,only a few studies in glioblastoma and neuroblastoma.In glioblastoma stem cells,HAUS5 knockdown resulted in loss of cell proliferation and tumorigenicity.Unfortunately,there are few studies on HAUS5 in breast cancer at home and abroad.This topic found that the high expression of HAUS5 is closely related to the prognosis and survival of breast cancer patients.A series of molecular biology experiments in vivo and in vitro verified that HAUS5 has a cancer-promoting effect in breast cancer,promoting breast cancer cell proliferation,migration and invasion,and inhibiting cell apoptosis.Death.At the same time,it was found for the first time that HAUS5 interacts with RICTOR,and HAUS5 can mediate RICTOR(RapamycinInsensitive Companion of mTOR)to regulate the malignant behavior of breast cancer cells through the AKT/mTOR signaling pathway,providing a new scientific basis and research basis for the study of the molecular mechanism of breast cancer development.Methods:1.Using multiple public databases,bioinformatics analysis was used to detect the expression,prognosis and clinicopathological characteristics of HAUS5 in various cancers,breast cancer tissues and adjacent tissues;2.High-throughput sequencing,immune Histochemistry and Western Blotting were used to detect the expression of HAUS5 in tumor tissues and corresponding adjacent tissues of breast cancer patients,and the relationship with clinicopathological characteristics;3.Select the top two breast cancer cell lines with the highest expression of HAUS5,HAUS5 knockdown cell model was constructed by RNA interference technology,and the efficiency of HAUS5 knockdown was tested by real-time fluorescent quantitative PCRand Western Blotting;4.MTT method,Celigo cell counting method and plate cloning experiment were used to observe The effect of HAUS5 status on the proliferation and growth of breast cancer cells HCC1937 and MDA-MB-231;5.Annexin V-APC flow cytometry to observe the effect of HAUS5 status on apoptosis of breast cancer cells HCC1937 and MDA-MB-231;6.Transwell assay to observe the effect of HAUS5 status on the migration and invasion of breast cancer cells HCC1937 and MDA-MB-231 7.Establish a nude mouse xenograft tumor model to observe the effect of HAUS5 status on the tumorigenic ability of breast cancer cell line MDA-MB231 in vivo;8.Coimmunoprecipitation(Co-IP)combined with mass spectrometry analysis and screening and HAUS5 interacts with protein molecules;9.Biological function phenotype experiments to observe the effect of HAUS5 binding on the screened interacting protein molecules on mammary glands.The effect of cancer cells;10.Using high-throughput transcriptome sequencing,to find the main regulatory changes of HAUS5 in breast cancer and the dependent signaling pathways,and use molecular biological experimental techniques to verify.Results:1.Analysis of multiple public databases showed that at the level of mRNA transcription and protein translation,the expression of HAUS5 was upregulated in breast cancer tissues compared with adjacent tissues;2.HAUS5 is correlated with T stage and ER status of BC patients;3.The prognosis of high HAUS5 expression is significantly lower than that of patients with low expression;4.In vitro experiments show that HAUS5 knockdown can inhibit the proliferation,migration and invasion of breast cancer cells,and block cell apoptosis;5.Nude mice subcutaneous tumor formation experiment It is proved that HAUS5 knockdown can inhibit the proliferation of breast cancer cells;6.HAUS5 has an interaction relationship with RICTOR;7.Overexpression of RICTOR after knockdown of HAUS5 can partially reverse the cell proliferation,migration and invasion caused by HAUS5 interference;8.HAUS5 through RICTOR Activation of AKT/mTOR signaling pathway affects the development of breast cancer.Conclusion:1.HAUS5 can promote the proliferation and invasion of breast cancer cells and inhibit cell apoptosis,thereby inducing the occurrence and development of breast cancer;2.RICTOR can partially reverse the malignant behavior of breast cancer cells caused by the down-regulation of HAUS5;HAUS5 activates AKT/mTOR signaling pathway through RICTOR. |
