TMEM160/Keap1-Nrf2 Signaling Pathway Suppresses Ferroptosis And Promotes Chemo-resistance In Gastric Cancer

Background:Gastric cancer is the second most common malignancy in China,and surgery is the main treatment for early-stage patients.Most patients require postoperative adjuvant chemotherapy,but there is still a lack of effective indicators to predict the efficacy of adjuvant chemotherapy.As a transmembrane protein,the TMEM family is involved in various biological functions of cells and is crucial for tumor invasion and metastasis.Moreover,the expression of its protein is mostly related to poor prognosis of patients.In previous studies,we found that TMEM160,a member of the TMEM family,is associated with ferroptosis,and its role and molecular mechanism in the development of gastric cancer have not been elucidated.Objective:To explore the biological function of TMEM160 in gastric cancer and to inhibit ferroptosis to promote chemotherapy resistance in gastric cancer cells through the Keap1-Nrf2 signaling pathway.Methods:1.Bioinformatics analysis and cellular validation to screen for key TMEM family genes and their relationship with ferroptosis in gastric cancer;2.Flow cytometry to detect changes in reactive oxygen species(ROS)levels in gastric cancer cells after downregulation of TMEM160 expression and induction of ferroptosis with the Erastin inducer;3.Flow cytometry to detect changes in apoptosis levels in gastric cancer cells after downregulation of TMEM160 expression;4.CCK8 proliferation assay to determine the effect of TMEM160 on gastric cancer cell growth rate;5.Transwell assay to determine the effect of TMEM160 on gastric cancer cell migration and invasion ability;6.CCK8 assay to detect changes in the sensitivity of gastric cancer cells to5-fluorouracil chemotherapy after downregulation of TMEM160 expression;7.Western blot to detect the effect of TMEM160 on the expression of Keap1-Nrf2 signaling pathway and ferroptosis-related proteins in gastric cancer.Results:1.Bioinformatics analysis indicated that TMEM160 has the highest correlation with GPX4,a key factor in ferroptosis in gastric cancer;2.Downregulation of TMEM160 expression led to an increase in intracellular ROS levels and sensitivity to the Erastin inducer of ferroptosis;3.Downregulation of TMEM160 expression did not significantly affect apoptosis levels in gastric cancer cells;4.Downregulation of TMEM160 expression led to a decrease in cell proliferation rate,while overexpression of TMEM160 increased cell proliferation rate;5.Downregulation of TMEM160 expression weakened cell migration and invasion ability,while overexpression of TMEM160 enhanced cell migration and invasion ability;6.Downregulation of TMEM160 expression increased the sensitivity of BGC-823 cells to 5-fluorouracil chemotherapy,while knockdown of TMEM160 decreased the sensitivity of BGC-823 cells to 5-fluorouracil chemotherapy;7.Downregulation of TMEM160 expression significantly reduced the expression levels of Nrf2,SLC7A11,and GPX4,while increasing the expression level of KEAP1 protein.Conclusion:1.Downregulation of TMEM160 inhibits the proliferation,migration,and invasion of gastric cancer cells,and increases the sensitivity to 5-fluorouracil chemotherapy,while overexpression has the opposite effect.2.TMEM160 inhibits ferroptosis and promotes chemotherapy resistance in gastric cancer cells through the Keap1-Nrf2 signaling pathway.