RESUMO
Extensive reprogramming of cellular energy metabolism is a hallmark of cancer. Despite its importance, the molecular mechanism controlling this tumour metabolic shift remains not fully understood. Here we show that 14-3-3σ regulates cancer metabolic reprogramming and protects cells from tumorigenic transformation. 14-3-3σ opposes tumour-promoting metabolic programmes by enhancing c-Myc poly-ubiquitination and subsequent degradation. 14-3-3σ demonstrates the suppressive impact on cancer glycolysis, glutaminolysis, mitochondrial biogenesis and other major metabolic processes of tumours. Importantly, 14-3-3σ expression levels predict overall and recurrence-free survival rates, tumour glucose uptake and metabolic gene expression in breast cancer patients. Thus, these results highlight that 14-3-3σ is an important regulator of tumour metabolism, and loss of 14-3-3σ expression is critical for cancer metabolic reprogramming. We anticipate that pharmacologically elevating the function of 14-3-3σ in tumours could be a promising direction for targeted anticancer metabolism therapy development in future.
Assuntos
Proteínas 14-3-3/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Metabolismo Energético/genética , Exorribonucleases/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas 14-3-3/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Intervalo Livre de Doença , Exorribonucleases/metabolismo , Feminino , Técnicas de Inativação de Genes , Glutamina/metabolismo , Glicólise/genética , Células HCT116 , Humanos , Pessoa de Meia-Idade , Biogênese de Organelas , Prognóstico , Proteólise , Ubiquitinação/genética , Adulto JovemRESUMO
FBXW7, a component of E3 ubiquitin ligase, plays an important role in mitotic checkpoint, but its role remains unclear. Aurora B is a mitotic checkpoint kinase that plays a pivotal role in mitosis by ensuring correct chromosome segregation and normal progression through mitosis. Whether Aurora B and FBXW7 are coordinately regulated during mitosis is not known. Here, we show that FBXW7 is a negative regulator for Aurora B. Ectopic expression of FBXW7 can suppress the expression of Aurora B. Accordingly, FBXW7 deficiency leads to Aurora B elevation. Mechanistic studies show that all FBXW7 isoforms are negative regulators of Aurora B expression through ubiquitination-mediated protein degradation. Aurora B interacts with R465 and R505 residues of WD 40 domain of FBXW7. Significantly, inverse correlation between FBXW7 and Aurora B elevation is translated into the deregulation of mitosis. FBWX7 expression mitigates Aurora B-mediated cell growth and mitotic deregulation. In addition, FBXW7 reduces the percentage of multinucleated cells caused by Aurora B overexpression. These data suggest that FBXW7 is an important negative regulator of Aurora B, and that the loss or mutation of FBXW7 as seen in many types of cancer could lead to an abnormal elevation of Aurora B and result in deregulated mitosis, which accelerates cancer cell growth.