The Mechanism Of HMOX1 Regulating Ferroptosis To Inhibit Glioma Growth

Background and Objective:Glioma is the most common malignant tumor of the central nervous system with poor prognosis.The current treatment is maximum surgical excision with radiotherapy and chemotherapy,but there are still some deficiencies such as difficult radical treatment,rapid proliferation and easy chemotherapy tolerance.Therefore,to clarify the pathogenesis of glioma,find new therapeutic means,and improve the prognosis of patients,has become an important topic to be solved urgently.Ferroptosis,as a newly discovered programmed cell death mode in recent years,is different from apoptosis,autophagy,necrosis and other cell death modes due to its iron dependence and lipid peroxide accumulation.However,the specific mechanism of ferroptosis in glioma remains to be further elucidated.Hemoxygenase 1(HMOX1)is an essential enzyme in the catabolism of heme.There have been few reports on the role of HMOX1 in ferroptosis caused by glioma.Starting from a new perspective of ferroptosis,this study further explored the role of HMOX1 in the occurrence and development of glioma and clarified the mechanism of its regulation on ferroptosis to provide experimental and theoretical basis for exploring the metabonomics based treatment strategy for glioma.Methods:The differential gene HMOX1 was screened by GEO data set,and the expression of HMOX1 in glioma tissues was determined by TCGA and GEO data set,so as to evaluate the value of HMOX1 as auxiliary diagnosis and prognosis evaluation of glioma.Immunohistochemical techniques were used to confirm the expression level of HMOX1 in glioma tissues.The expression of HMOX1 in classical glioma cell lines was detected by Western Blot and RT-qPCR.The expression of HMOX1 in classical glioma cell lines U87 and U251 was down-regulated.The effect of down-regulated HMOX1 on the proliferation of glioma was evaluated by CCK8 proliferation curve and Edu experiment.The effect of down-regulated HMOX1 on ferroptosis indicators of glioma was detected by ROS experiment and MDA experiment.The effect of HMOX1 on the tumorigenic ability of glioma was examined by constructing intracranial in situ tumor model in nude mice.Western Blot,RT-qPCR,Sequencing and co-immunoprecipitation were used to verify the relationship between HMOX1 and AKR1B1(Aldo-Keto Reductase Family 1 Member B).ROS and MDA experiments were used to detect the effect of down-regulated AKR1B1 on ferroptosis indicators of glioma.Results:Biogenic analysis indicated that HMOX1 was highly expressed in glioma tissues.The expression level of HMOX1 was closely related to the poor prognosis of glioma.Western Blot indicated that HMOX1 was highly expressed in glioma cells.Immunohistochemical experiments indicated that HMOX1 was highly expressed in glioma cells.In vitro experiments indicated that the proliferation ability of glioma cell lines U87 and U251 was decreased after the downregulation of HMOX1.In vivo experiments of nude mice,the growth of intracranial glioma was significantly slowed down and the survival time was prolonged after the downregulation of HMOX1.The study of cell signaling pathway suggested that the expression of AKR1B1 in U87 and U251 cells was increased after the downregulation of HMOX1.Second generation sequencing and co-immunoprecipitation suggested that AKR1B1 interacted with HMOX1.After down-regulation of AKR1B1,the levels of MDA and ROS were increased in U87 and U251 cell lines,suggesting that the level of ferroptosis was increased.Conclusion:HMOX1 is highly expressed in glioma cells and is closely related to the prognosis of glioma patients.The interaction between HMOX1 and AKR1B1 may be involved in the regulation of ferroptosis level in glioma,thereby inhibiting the growth of glioma.HMOX1 can be used as a target for glioma treatment.