Study On The Mechanism Of Attenuated Expression Of ALDH2 Mediated By ERβ Promotes Invasion And Vasculogenic Mimicry Formation Of Bladder Cancer Via Modulating MMP-1

Background: Bladder cancer is one of the most common malignant tumors of the urinary system,and approximately 573,000 new cases and213,000 deaths occurred all around the world in 2020.Although the incidence of bladder cancer is 2-4 times higher in men than in women,the malignancy of bladder cancer tends to be higher in female patients.The possible involvement of Estrogen Receptor beta(ERβ)in the progress of bladder cancer has been proposed,however the mechanisms and details need further study.Aldehyde dehydrogenase 2(ALDH2)mainly involves in detoxifying toxic acetaldehyde to non-toxic acetic acid.Recently,studies have found that ALDH2 is a tumor suppressor gene,which has low expression in a variety of tumors and can inhibit the invasion and metastasis of tumor cells.However,the role of ALDH2 in the development of bladder cancer is unclear.Objective: 1.To explore the role of ALDH2 in bladder cancer invasion and metastasis and vasculogenic mimicry(VM).2.To clarify the role of ALDH2 in the progression of bladder cancer.3.To clarify the mechanism of regulating the upstream gene of ALDH2 and downstream gene of ALDH2 to regulate the invasion,metastasis and VM of bladder cancer.4.To provide new ideas for the prevention and treatment of bladder cancer.Method: We collected 11 pairs of cancer and normal tissues in patients undergoing radical cystectomy in Xiangya Hospital,Central South University.Microarray sequencing was used to detect the differentially expressed genes.The differentially expressed genes and the impact in prognosis of bladder cancer were verified in The Cancer Genome Atlas(TCGA)database.65 pairs of cancer and normal tissues were collected in patients undergoing radical cystectomy in Xiangya Hospital,Central South University and Immunohistochemistry(IHC)was used to detect the protein expression.Chamber-Transwell invasion was used to detect the invasion ability of bladder cancer cells.,we assessed the VM formation of bladder cancer cells by evaluating the ability of bladder cancer cells to form a tube on the surface of Matrigel.Western blot was used to detect the expression of proteins.By designing appropriate primers,the expression of m RNAs and mi RNAs was detected by quantitative real-time polymerase chain reaction(q RT-PCR).RNA protein immunoprecipitation(RIP)was used to analyze the binding of RNA and protein in cells.Chromatin immunoprecipitation(Ch IP)was used to analyze the binding of DNA and protein in cells.The interaction between intracellular proteins was analyzed by Co-Immunoprecipitation(Co-IP).The mechanism of related molecules was studied by dual-luciferase reporter assay.Finally,an orthotopically xenografting in vivo mouse bladder cancer model was used to confirm the in vitro results.Results: Microarray sequencing identified the expression of ALDH2 m RNA was significantly lower in bladder cancer than normal tissue and the results were consistent in TCGA database(P<0.05).In bladder cancer patients,lower levels of ALDH2 expression were associated with poor prognosis.IHC showed the expression of ALDH2 in bladder cancer tissues was significantly lower than that in adjacent tissues(P < 0.05).In vitro,we demonstrated that ALDH2 was down-regulated by ERβ/mi R-30a-5p signals.Repressed ALDH2 could promote the invasion and VM formation of bladder cancer via alerting the expression of the invasion marker gene MMP-1.Mechanism experiments show that ERβcould promote the expression of mi R-30a-5p by binding to the promoter region of its host gene and mi R-30a-5p could down regulate ALDH2 expression through binding to the 3’UTR of ALDH2 m RNA.ALDH2 protein could inhibit the exocrinosity of MMP-1 by binding with MMP-1protein,so as to regulate cell invasion and VM.The main experiments were carried out in 2 bladder cancer cell lines T24 and TCCSUP.Finally,bladder cancer cells with high expression of ERβ and low expression of ALDH2 showed higher metastasis rate in orthotopic tumor model.Conclusion: This study identified the attenuated expression of ALDH2 suppressed by ERβ/mi R-30a-5p signals could promote bladder cancer invasion and VM formation via modulating MMP-1 expression and exocrinosity.This article includes 33 figures,20 sheets and 132 references.