LINC01116 binds CPS1 to regulate urea cycle function, thereby promoting progression and chemoresistance in osteosarcoma

Osteosarcoma is the most common primary malignant bone tumor in children and adolescents. The purpose of this study is to explore the regulatory mechanism of LINC01116 in osteosarcoma metastasis and its potential association with the urea cycle and chemoresistance. Transcriptomic profiling was performed, and the results were validated by qRT-PCR in 6 paired osteosarcoma and adjacent non-tumor tissues. Functional assays including in vivo xenograft models were used to verify the effect of LINC01116 on osteosarcoma cell proliferation. RNA-protein interaction studies and ChIRP-MS assays were conducted to confirm the binding between LINC01116 and CPS1.LINC01116 was significantly upregulated in metastatic osteosarcoma lesions. Silencing LINC01116 inhibited osteosarcoma cell proliferation both in vitro and in vivo. Mechanistically, LINC01116 directly binds to CPS1 -the rate-limiting enzyme of the urea cycle, which was confirmed by ChIRP-MS. Perturbing the LINC01116/CPS1 axis reduced citrulline levels, indicating impaired urea cycle function. Additionally, CPS1 silencing enhanced osteosarcoma cell sensitivity to cisplatin. This study identifies a novel LINC01116/CPS1 axis that drives osteosarcoma metastasis by regulating the urea cycle. Targeting this axis can sensitize osteosarcoma to cisplatin treatment, which highlights its potential as a therapeutic target for osteosarcoma.