Taurine and proline promote lung tumour growth by co-regulating Azgp1/mTOR signalling pathway.

Accurate metabolic biomarkers for lung cancer prognosis remain scarce but crucial. Taurine and proline, two metabolites, are consistently elevated across various cancer stages in previous studies, hinting at their potential role in disease progression. This study is the first to reveal how these metabolites contribute to poor prognosis. Transcriptomic analysis uncovered that taurine and proline downregulated Zinc-α2-glycoprotein (Azgp1), a gene linked to key metabolic pathways. Additionally, Azgp1 could also significantly affect downstream lipid metabolic pathways in lung cancer. Both taurine and proline influenced lipid metabolism via mammalian target of rapamycin (mTOR). When Azgp1 was overexpressed, lung cancer progression slowed significantly, alongside reduced mTOR activity. These findings underscore the pro-cancer role of taurine and proline, highlighting the Azgp1/mTOR axis as a vital, yet overlooked, pathway in lung cancer. This study not only advances our understanding but also identifies new therapeutic avenues.