ANXA1 promotes intrahepatic cholangiocarcinoma proliferation and growth by regulating glutamine metabolism through GOT1 stabilization.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a malignant tumor with a poor prognosis, marked by a postoperative recurrence rate of 50-60% and a 5-year survival rate of 8-30%. Abnormal tumor metabolism, particularly, amino acid metabolism, plays a key role in malignant progression. However, the molecular mechanisms linking amino acid metabolism to ICC progression remain unclear. METHODS: Bioinformatics was used to identity the key amino acid metabolism related gene in ICC, qRT-PCR, western blotting and immunohistochemical (IHC) were used to detect the expression of ANXA1 in normal tissues or ICC tissues and cells at mRNA and protein levels. The effects of ANXA1 on the proliferation ability of ICC in vitro and in vivo were investigated using CCK8, cloning formation experiment, EdU, IHC, nude mice subcutaneous tumorigenesis model. Immunoprecipitation, mass spectrometry analysis, protein ubiquitin level detection test, immunofluorescence co-localization, and redox stress metabolite detection test were used to explore the metabolism-related regulatory mechanism of ANXA1. RESULTS: we employed bioinformatics analysis to classify ICC into metabolic subgroups with distinct prognoses and identified the associated biomarker Annexin A1(ANXA1), whose high expression is correlated with poor prognosis and promotes ICC development. Mass spectrometry analysis revealed that ANXA1 interacts with the key enzyme in glutamine metabolism, glutamic-oxaloacetic transaminase 1(GOT1). Through in vitro and in vivo experiments, overexpressed ANXA1 stabilizes GOT1 by recruiting the deubiquitinase USP5. This stabilization enhances glutamine uptake, as well as the production of aspartate and glutamate, which in turn reduces oxidative stress, thereby promoting tumor cell growth. Moreover, knockdown of ANXA1 combined with glutamine uptake inhibition significantly suppressed ICC cell proliferation and Inhibited subcutaneous tumor formation and growth. CONCLUSIONS: These results suggest that the ANXA1/USP5/GOT1 axis promotes glutamine metabolism and ICC proliferation and growth. Inhibiting ANXA1 alongside glutamine uptake inhibition offers a promising strategy for treating ICC.