Activation of SREBP-1c alters lipogenesis and promotes tumor growth and metastasis in gastric cancer.

Purpose: Aggressively growing tumors are characterized by significant variations in metabolites, including lipids, and can involve the elevated synthesis ofde novo fatty acids.

Methods: Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)-based metabolomics and lipidomics were performed to compare human gastric cancer tissues and adjacent normal tissues from clinical patients. A series of cellular and molecular biological methods were applied to validate the lipidomics results.

Results: Palmitic acid (PA) was found to be significantly downregulated in gastric cancer tissues, and it was found that a high concentration of PA specifically inhibited cell proliferation and impaired cell invasiveness and migrationin vitro in AGS, SGC-7901, and MGC-803 gastric cancer cell lines. Moreover, sterol regulatory element-binding protein 1 (SREBP-1c) was activated in human gastric cancer tissues, and it promoted the expression of a series of genes associated with the synthesis of fatty acids, such as SCD1 and FASN. SREBP-1c knockdown rescued the migration and invasion defects in AGS and SGC-7901 gastric cancer cells.

Conclusion: Taken together, our findings confirmed the variation in fatty acid synthesis in gastric cancer and identified SREBP-1c as a promising target for gastric cancer treatment.