SUMOylation of TEAD1 Modulates the Mechanism of Pathological Cardiac Hypertrophy.

Pathological cardiac hypertrophy is the leading cause of heart failure and has an extremely complicated pathogenesis. TEA domain transcription factor 1 (TEAD1) is recognized as an important transcription factor that plays a key regulatory role in cardiovascular disease. This study aimed to explore the role of TEAD1 in cardiac hypertrophy and to clarify the regulatory role of small ubiquitin-like modifier (SUMO)-mediated modifications. First, the expression level of TEAD1 in patients with heart failure, mice, and cardiomyocytes is investigated. It is discovered that TEAD1 is modified by SUMO1 during cardiac hypertrophy and that the process of deSUMOylation is regulated by SUMO-specific protease 1 (SENP1). Lysine 173 is an essential site for TEAD1 SUMOylation, which affects the protein stability, nuclear localization, and DNA-binding ability of TEAD1 and enhances the interaction between TEAD1 and its transcriptional co-activator yes-associated protein 1 in the Hippo pathway. Finally, adeno-associated virus serotype 9 is used to construct TEAD1 wild-type and KR mutant mice and demonstrated that the deSUMOylation of TEAD1 markedly exacerbated cardiomyocyte enlargement in vitro and in a mouse model of cardiac hypertrophy. The results provide novel evidence that the SUMOylation of TEAD1 is a promising therapeutic strategy for hypertrophy-related heart failure.

AMPKα2 regulates fasting-induced hyperketonemia by suppressing SCOT ubiquitination and degradation.

Ketone bodies serve as an energy source, especially in the absence of carbohydrates or in the extended exercise. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is a crucial energy sensor that regulates lipid and glucose metabolism. However, whether AMPK regulates ketone metabolism in whole body is unclear even though AMPK regulates ketogenesis in liver. Prolonged resulted in a significant increase in blood and urine levels of ketone bodies in wild-type (WT) mice. Interestingly, fasting AMPKα2-/- and AMPKα1-/- mice exhibited significantly higher levels of ketone bodies in both blood and urine compared to fasting WT mice. BHB tolerance assays revealed that both AMPKα2-/- and AMPKα1-/- mice exhibited slower ketone consumption compared to WT mice, as indicated by higher blood BHB or urine BHB levels in the AMPKα2-/- and AMPKα1-/- mice even after the peak. Interestingly, fasting AMPKα2-/- and AMPKα1-/- mice exhibited significantly higher levels of ketone bodies in both blood and urine compared to fasting WT mice. . Specifically, AMPKα2ΔMusc mice showed approximately a twofold increase in blood BHB levels, and AMPKα2ΔMyo mice exhibited a 1.5-fold increase compared to their WT littermates after a 48-h fasting. However, blood BHB levels in AMPKα1ΔMusc and AMPKα1ΔMyo mice were as same as in WT mice. Notably, AMPKα2ΔMusc mice demonstrated a slower rate of BHB consumption in the BHB tolerance assay, whereas AMPKα1ΔMusc mice did not show such an effect. Declining rates of body weights and blood glucoses were similar among all the mice. Protein levels of SCOT, the rate-limiting enzyme of ketolysis, decreased in skeletal muscle of AMPKα2-/- mice. Moreover, SCOT protein ubiquitination increased in C2C12 cells either transfected with kinase-dead AMPKα2 or subjected to AMPKα2 inhibition. AMPKα2 physiologically binds and stabilizes SCOT, which is dependent on AMPKα2 activity.

The discordance pattern of molecular sub-types between primary and metastatic sites in Chinese breast cancer patients.

OBJECTIVE: Based on estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor (HER-2), and proliferation cell nuclear antigen (Ki-67) status, breast cancer (BC) can be divided into several molecular sub-types. The patterns of these biological receptors may change during the course of progression and metastasis which could lead to new treatment strategies accordingly. METHOD: The present multi-center-based clinical data investigated the discordance patterns of molecular features in Chinese BC patients between primary tumors and distant metastasis. 151 pathologically confirmed BC patients were enrolled. The comparison of the statuses of ER, PR, HER-2, and the Ki-67 index by the IHC and/or FISH method was performed. RESULTS: The discordance rate in one or more molecular markers was 52.4% and varied between primary and metastatic lesions. The most common transformation pattern was the loss of ER and PR. On the other hand, the ER-positive patients have the longest OS. Patients with ER changing from positive to negative have the shortest OS. The patients with PR changing from negative to positive have the longest OS, while PR-negative patients have the shortest OS. The median DFI (disease-free interval) was 54.93 months in this study. ER, PR, and HER-2 transformation rates are common in patients with DFI < 2 years than in patients with DFI ≥ 5 years. For patients with an ER-positive expression in metastatic lesions, a significantly prolonged PFS was observed (P < 0.05) in those receiving endocrine treatment. CONCLUSION: The transformation of molecular subtyping status was identified between primary and corresponding relapse lesions and was used for determining the treatment strategies and prognosis prediction in advanced BC patients.