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Marques Junior, J.

Publications and source records attributed to Marques Junior, J..

2 recordsLinked to original sources

mTORC2 stabilizes HIF-1β to coordinate metabolic adaptation in lung cancer

Despite extensive genetic heterogeneity, lung tumors frequently converge on shared signaling dependencies that remain therapeutically underexploited. Here, we identify mTORC2 signaling as a convergent dependency across genetically distinct lung cancer subtypes and uncover HIF-1{beta} as a selective metabolic effector downstream of mTORC2 that promotes lung tumor progression. Elevated mTORC2 signaling in lung adenocarcinoma was associated with poor overall survival, metastatic dissemination and metabolic rewiring. Using complementary genetically engineered mouse models of Rictor deletion or overexpression in Kras-driven lung tumors, we show that mTORC2 activity is dispensable for normal lung homeostasis but required for tumor progression and metabolic adaptation in vivo. Mechanistically, mTORC2 stabilized HIF-1{beta} by preventing its ubiquitin-independent proteasomal degradation through a non-canonical PKC-CK2 signaling axis, independently of AKT. Integrated multi-omics analyses identified extensive metabolic rewiring downstream of the mTORC2-HIF-1{beta} axis, with sphingolipid metabolism emerging as a prominent and therapeutically exploitable vulnerability. Accordingly, pharmacological targeting of sphingolipid metabolism markedly impaired the growth of mTORC2-driven lung tumors in vivo. Together, our findings establish a non-canonical mTORC2-HIF-1{beta} signaling axis that couples oncogenic signaling to metabolic adaptation and defines therapeutically actionable metabolic vulnerabilities in lung cancer.

cancer biology↗

FAK modulates glioblastoma stem cell energetics via actomyosin contractility: regulation of glycolysis and mitochondrial function

Glycolysis and the TCA cycle are reprogrammed in cancer cells to meet bioenergetic and biosynthetic demands, including by engagement with the extracellular matrix (ECM). We show that focal adhesion kinase (FAK), a mediator of integrin-ECM signalling, is driving cellular energetics in a stem cell model of glioblastoma (GBM). FAK gene deletion inhibits both glycolysis and glutamine oxidation, with increased mitochondrial fragmentation and elevated phosphorylation of the mitochondrial protein MTFR1L at S235. Simultaneously, FAK loss causes a mesenchymal to epithelial transition, enhanced acto-myosin contractility as shown by phospho-myosin light chain (p-MLC S19) and impaired cell migration/invasiveness. Rho-kinase (ROCK) inhibitors suppress p-MLC (S19) and restore glutamine oxidation and elongation of mitochondria. Thus, FAK is a key regulator of both glycolysis and glutamine oxidation mediated by acto-myosin contractility that controls both cell and mitochondrial morphology. Moreover, FAK-dependent cellular energetics are coincident properties with GBM stem cell migration, invasiveness and tumour growth in vivo.

cancer biology↗