a Cancer Research Center, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361102, P. R. China;
b State Key Laboratory of Cellular Stress Biology, School of Life Sciences, Faculty of Medicine and Life Sciences, Xiamen University, Xiamen, Fujian 361102, P. R. China;
c Department of Retroperitoneal Tumor Surgery, Peking University International Hospital, Beijing, 102206, P. R. China;
d School of Public Health, Harvard University, Boston, MA, USA;
e Department of Laboratory Medicine, Xiang'an Hospital of Xiamen University, Xiamen University, Xiamen, Fujian 361102, P. R. China;
f National Institute for Data Science in Health and Medicine, Xiamen University, Xiamen, Fujian 361102, P. R. China;
g Laboratory of Biochemistry and Molecular Biology Research, Department of Clinical Laboratory, Fujian Medical University Cancer Hospital, Fujian 350014, P. R. China;
h Department of Hepatobiliary Surgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian 361102, P. R. China;
i Department of General Surgery, Peking University People's Hospital, Beijing, 100032, P. R. China;
j Department of Gastrointestinal Surgical Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fujian 350014, P. R. China;
k Department of Management, Jiang Xia Blood Technology Co., Ltd., Shanghai 200000, P. R. China
Funds:
We thank Haiping Zheng at the Central laboratory, school of Medicine, Xiamen University for providing scientific and technical support. This work was supported by grants from the National Natural Science Foundation of China (No. 82272935 to WG.L., No. 91957120 and 21974114 to S.-H.L.), the Postdoctoral Fellowship Program of CPSF (No. GZC20240901 to FA.X), the Xiamen medical industry combined guidance project (No. 3502Z20244ZD2022 to FA. X), the Scientific Research Foundation for Advanced Talents, Xiang’an Hospital of Xiamen University (No. PM20180917008 to WG. L.), the Fundamental Research Funds for the Central Universities (20720210001 to S.-H.L.) and Major Science and Technology Special Project of Fujian Province (2022YZ036012 to S.-H.L.). Joint laboratory of School of Medicine, Xiamen University-Shanghai Jiangxia Blood Technology Co. LTD (No. XDHT2020010C to WG.L.). Joint research center of School of Medicine, Xiamen University-Jiangsu Charity Biotech Co.,Ltd (No. 20233160C0002 to WG.L.).
Ursodeoxycholic acid (UDCA) is a naturally occurring, low-toxicity, and hydrophilic bile acid (BA) in the human body that is converted by intestinal flora using primary BA. Solute carrier family 7 member 11 (SLC7A11) functions to uptake extracellular cystine in exchange for glutamate, and is highly expressed in a variety of human cancers. Retroperitoneal liposarcoma (RLPS) refers to liposarcoma originating from the retroperitoneal area. Lipidomics analysis revealed that UDCA was one of the most significantly downregulated metabolites in sera of RLPS patients compared with healthy subjects. The augmentation of UDCA concentration (≥25 μg/mL) demonstrated a suppressive effect on the proliferation of liposarcoma cells. [15N2]-cystine and [13C5]-glutamine isotope tracing revealed that UDCA impairs cystine uptake and glutathione (GSH) synthesis. Mechanistically, UDCA binds to the cystine transporter SLC7A11 to inhibit cystine uptake and impair GSH de novo synthesis, leading to reactive oxygen species (ROS) accumulation and mitochondrial oxidative damage. Furthermore, UDCA can promote the anticancer effects of ferroptosis inducers (Erastin, RSL3), the murine double minute 2 (MDM2) inhibitors (Nutlin 3a, RG7112), cyclin dependent kinase 4 (CDK4) inhibitor (Abemaciclib), and glutaminase inhibitor (CB839). Together, UDCA functions as a cystine exchange factor that binds to SLC7A11 for antitumor activity, and SLC7A11 is not only a new transporter for BA but also a clinically applicable target for UDCA. More importantly, in combination with other antitumor chemotherapy or physiotherapy treatments, UDCA may provide effective and promising treatment strategies for RLPS or other types of tumors in a ROS-dependent manner.