The cystine/glutamate antiporter SLC7A11(also commonly known as xCT)functions to import cystine for glutathione biosynthesis and antioxidant defense and is overexpressed in multiple human cancers.Recent studies reveal...The cystine/glutamate antiporter SLC7A11(also commonly known as xCT)functions to import cystine for glutathione biosynthesis and antioxidant defense and is overexpressed in multiple human cancers.Recent studies revealed that SLC7A11 overexpression promotes tumor growth partly through suppressing ferroptosis,a form of regulated cell death induced by excessive lipid peroxidation.However,cancer cells with high expression of SLC7A11(SLC7A11^(high))also have to endure the significant cost associated with SLC7A11-mediated metabolic reprogramming,leading to glucose-and glutamine-dependency in SLC7A11^(high) cancer cells,which presents potential metabolic vulnerabilities for therapeutic targeting in SLC7A11^(high) cancer.In this review,we summarize diverse regulatory mechanisms of SLC7A11 in cancer,discuss ferroptosis-dependent and-independent functions of SLC7A11 in promoting tumor development,explore the mechanistic basis of SLC7A11-induced nutrient dependency in cancer cells,and conceptualize therapeutic strategies to target SLC7A11 in cancer treatment.This review will provide the foundation for further understanding SLC7A11 in ferroptosis,nutrient dependency,and tumor biology and for developing novel effective cancer therapies.展开更多
Cancer cells often upregulate nutrient transporters to fulfill their increased biosynthetic and bioenergetic needs,and to maintain redox homeostasis.One nutrient transporter frequently overexpressed in human cancers i...Cancer cells often upregulate nutrient transporters to fulfill their increased biosynthetic and bioenergetic needs,and to maintain redox homeostasis.One nutrient transporter frequently overexpressed in human cancers is the cystine/glutamate antiporter solute carrier family 7 member 11(SLC7A11;also known as xCT).SLC7A11 promotes cystine uptake and glutathione biosynthesis,resulting in protection from oxidative stress and ferroptotic cell death.Recent studies have unexpectedly revealed that SLC7A11 also plays critical roles in glutamine metabolism and regulates the glucose and glutamine dependency of cancer cells.This review discusses the roles of SLC7A11 in regulating the anti-oxidant response and nutrient dependency of cancer cells,explores our current understanding of SLC7A11 regulation in cancer metabolism,and highlights key open questions for future studies in this emerging research area.A deeper understanding of SLC7A11 in cancer metabolism may identify new therapeutic opportunities to target this important amino acid transporter for cancer treatment.展开更多
基金The research in authors'lab has been supported by The University of Texas MD Anderson Cancer Center,KC180131 from Department of Defense Kidney Cancer Research Program,R01CA181196,R01CA190370,R01CA244144 from the National Institutes of Health(to BG)CPRIT Research Training Grant(RP170067)Dr.John J.Kopchick Research Award from The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences(to PK).
文摘The cystine/glutamate antiporter SLC7A11(also commonly known as xCT)functions to import cystine for glutathione biosynthesis and antioxidant defense and is overexpressed in multiple human cancers.Recent studies revealed that SLC7A11 overexpression promotes tumor growth partly through suppressing ferroptosis,a form of regulated cell death induced by excessive lipid peroxidation.However,cancer cells with high expression of SLC7A11(SLC7A11^(high))also have to endure the significant cost associated with SLC7A11-mediated metabolic reprogramming,leading to glucose-and glutamine-dependency in SLC7A11^(high) cancer cells,which presents potential metabolic vulnerabilities for therapeutic targeting in SLC7A11^(high) cancer.In this review,we summarize diverse regulatory mechanisms of SLC7A11 in cancer,discuss ferroptosis-dependent and-independent functions of SLC7A11 in promoting tumor development,explore the mechanistic basis of SLC7A11-induced nutrient dependency in cancer cells,and conceptualize therapeutic strategies to target SLC7A11 in cancer treatment.This review will provide the foundation for further understanding SLC7A11 in ferroptosis,nutrient dependency,and tumor biology and for developing novel effective cancer therapies.
基金supported by the Andrew Sabin Family Fellow Award and Institutional Research Grant from the University of Texas MD Anderson Cancer Center,Grants from National Institutes of Health(CA181196 and CA190370)Anna Fuller Fund,and Ellison Medical Foundation(AG-NS-0973-13).
文摘Cancer cells often upregulate nutrient transporters to fulfill their increased biosynthetic and bioenergetic needs,and to maintain redox homeostasis.One nutrient transporter frequently overexpressed in human cancers is the cystine/glutamate antiporter solute carrier family 7 member 11(SLC7A11;also known as xCT).SLC7A11 promotes cystine uptake and glutathione biosynthesis,resulting in protection from oxidative stress and ferroptotic cell death.Recent studies have unexpectedly revealed that SLC7A11 also plays critical roles in glutamine metabolism and regulates the glucose and glutamine dependency of cancer cells.This review discusses the roles of SLC7A11 in regulating the anti-oxidant response and nutrient dependency of cancer cells,explores our current understanding of SLC7A11 regulation in cancer metabolism,and highlights key open questions for future studies in this emerging research area.A deeper understanding of SLC7A11 in cancer metabolism may identify new therapeutic opportunities to target this important amino acid transporter for cancer treatment.
