Transcriptional Reprogramming of Cancer Metabolism: Tricholoma terreum Inhibits Nucleotide Biosynthesis and Energy Flux in MCF-7 Cells by Downregulating DHFR, TK1, and ENO1

Tricholoma terreum, a mushroom rich in bioactive compounds, exhibits notable antioxidant and anticancer properties. Despite its traditional use, its effects on breast cancer metabolism remain underexplored. Here, we conducted comprehensive phytochemical and volatile organic compound profiling of T. terreum extracts and evaluated their cytotoxicity against MCF-7 breast cancer cells. Using SPME–GC–MS and HPLC, we identified a complex chemical matrix dominated by organic acids (acetic acid, 43.85%) and nitrogen-containing heterocyclics (2-acetylpyridine, 15.19%), alongside significant phenolic acids such as gallic acid and syringic acid. Biological assays indicated that the ethanol extract showed notable cytotoxic effects, reducing MCF-7 cell viability to 3.64% after 72 h, while higher viability was preserved in healthy CCD-1072sk fibroblast cells. Using cell viability assays, flow cytometry, and gene expression analysis, we found that ethanol extracts selectively reduced cancer cell viability, induced G0/G1 cell cycle arrest (71.92%), and promoted apoptosis. Mechanistically, treatment downregulated key nucleotide biosynthesis genes (DHFR, TK1) and the glycolytic enzyme gene (ENO1), while upregulating the oxidative stress response gene SLC7A11 (18.32-fold), suggesting disruption of cancer metabolic pathways. These findings reveal a metabolic reprogramming effect of T. terreum extracts, highlighting their potential as metabolism-targeted agents in breast cancer therapy. Further studies are warranted to validate these effects in vivo and isolate active constituents.