2-Hydroxylation of Fatty Acids Represses Colorectal Tumorigenesis and Metastasis via the YAP Transcriptional Axis.

Alteration in lipid composition is an important metabolic adaptation by cancer cells to support tumorigenesis and metastasis. Fatty acid 2-hydroxylase (FA2H) introduces a chiral hydroxyl group at the second carbon of fatty acid (FA) backbones and influences lipid structures and metabolic signaling. However, the underlying mechanisms through which FA 2-hydroxylation is coupled to metabolic adaptation and tumor growth remain elusive. Here, we show that FA2H regulates specific metabolic reprogramming and oncogenic signaling in the development of colorectal cancer. FA2H is highly expressed in normal colorectal tissues. Assessments through deciphering both published high-throughput data and curated human colorectal cancer samples revealed significant suppression of FA2H in tumors, which is correlated with unfavorable prognosis. Experiments with multiple models of genetic manipulation or treatment with an enzymatic product of FA2H, (R)-2-hydroxy palmitic acid, demonstrated that FA 2-hydroxylation inhibits colorectal cancer cell proliferation, migration, epithelial-to-mesenchymal transition progression, and tumor growth. Bioinformatics analysis suggested that FA2H functions through AMP-activated protein kinase/Yes-associated protein (AMPK/YAP) pathway, which was confirmed in colorectal cancer cells, as well as in tumors. Lipidomics analysis revealed an accumulation of polyunsaturated fatty acids in cells with FA2H overexpression, which may contribute to the observed nutrient deficiency and AMPK activation. Collectively, these data demonstrate that FA 2-hydroxylation initiates a metabolic signaling cascade to suppress colorectal tumor growth and metastasis via the YAP transcriptional axis and provides a strategy to improve colorectal cancer treatment. SIGNIFICANCE: These findings identify a novel metabolic mechanism regulating the tumor suppressor function of FA 2-hydroxylation in colorectal cancer. ©2020 American Association for Cancer Research.