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Morandi, A.

Publications and source records attributed to Morandi, A..

3 recordsLinked to original sources

MAPK15 Protects Against The Development Of Metabolic Dysfunction-Associated Steatotic Liver Disease

Accumulation of lipids in the liver characterizes metabolic dysfunction-associated steatotic liver disease (MASLD), the most prevalent chronic liver disease worldwide. As liver injury progresses to metabolic dysfunction-associated steatohepatitis (MASH), MASLD can predispose individuals to cirrhosis and hepatocellular carcinoma. Here, we characterized the first knockout mouse model for mitogen-activated protein kinase 15 (MAPK15) and revealed its critical role in controlling lipid homeostasis in the liver. Indeed, Mapk15-/- mice exhibited a MASLD-like phenotype, and hepatocellular models allowed us to demonstrate that dysregulated accumulation of lipids was due to increased expression and membrane localization of the CD36 fatty acid translocase. Consistently, Mapk15-/- mice exhibited elevated hepatic levels of CD36 and feeding them with a western-type diet significantly accelerated their progression to a MASH-like phenotype. Ultimately, transcriptomic analysis of human cohorts revealed increased liver expression of MAPK15 in MASLD patients, compared to unaffected individuals, ultimately supporting a protective role for MAPK15 against this disease. Overall, our data highlight a critical role for MAPK15 in liver physiopathology, by contributing to maintain physiological intracellular levels of lipids in this tissue.

cell biology↗

FADS1/2-mediated lipid metabolic reprogramming drives ferroptosis sensitivity in triple-negative breast cancer

Triple-negative breast cancer (TNBC) has limited therapeutic options, is highly metastatic and characterized by early recurrence. Lipid metabolism is generally deregulated in TNBC and might reveal vulnerabilities to be targeted or used as biomarkers with clinical value. Ferroptosis is a type of cell death caused by iron-dependent lipid peroxidation which is facilitated by the presence of polyunsaturated fatty acids (PUFA). Here we identify fatty acid desaturases 1 and 2 (FADS1/2), which are responsible for PUFA biosynthesis, lipid susceptible to peroxidation, to be highly expressed in a subset of TNBC with a poorer prognosis. Lipidomic analysis, coupled with functional metabolic assays, showed that FADS1/2 high-expressing TNBC are susceptible to ferroptosis-inducing agents and that targeting FADS1/2 renders those tumors ferroptosis-resistant. These findings were validated in vitro and in vivo in mouse and human-derived clinically relevant models and in a retrospective cohort of TNBC patients. One sentence summaryThe availability of intracellular PUFA depends on FADS1/2 desaturases, expressed at higher levels in aggressive triple-negative breast cancers highly susceptible to ferroptosis.

cancer biology↗

CANCER-ASSOCIATED FIBROBLASTS PROMOTE PROSTATE CANCER MALIGNANCY VIA METABOLIC REWIRING AND MITOCHONDRIAL TRANSFER

Cancer-associated fibroblasts (CAFs) are the major cellular stromal component of many solid tumors. In prostate cancer (PCa), CAFs establish a metabolic symbiosis with PCa cells, contributing to cancer aggressiveness through lactate shuttle. In this study, we report that lactate uptake alters the NAD+/NADH ratio in the cancer cells, which culminates with SIRT1-dependent PGC-1 activation and subsequent enhancement of mitochondrial mass and activity. The high exploitation of mitochondria results in tricarboxylic acid cycle deregulation, accumulation of oncometabolites and in the altered expression of mitochondrial complexes, responsible for superoxide generation. Additionally, cancer cells hijack CAF-derived functional mitochondria through the formation of cellular bridges, a phenomenon that we observed in both in vitro and in vivo PCa models. Our work reveals a crucial function of tumor mitochondria as the energy sensors and transducers of CAF-dependent metabolic reprogramming and underscores the reliance of PCa cells on CAF catabolic activity and mitochondria trading.

cancer biology↗