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Date, Y.

Publications and source records attributed to Date, Y..

2 recordsLinked to original sources

Identification of novel autophagy inducers by accelerating lysosomal clustering against Parkinson's disease

Autophagy-lysosome pathway plays an indispensable role in the intracellular protein quality control system, degrading abnormal organelles and proteins. Among these proteins is -Synuclein (Syn), which is associated with the pathogenesis of Parkinsons disease (PD). However, the activation of this lysosome-dependent degradation strategy is restricted by enzyme complementation. In this study, we focused on the phase of autophagosome-lysosome fusion around the microtubule organizing center (MTOC) that leads to Syn degradation. Through high-throughput chemical screening, we identified six clinically available drugs that enhance autophagy and can accumulate lysosomes around the MTOC from approximately 1,200 drugs screened. We further demonstrated that these compounds induce lysosomal clustering through a JIP4-TRPML1-dependent mechanism, which is associated with autophagy induction. Among these, the lysosomal clustering compound albendazole was observed to promote the autophagy-dependent degradation of Triton-X-insoluble proteasome inhibitor-induced aggregates (p62). In a cellular PD model, albendazole boosted the degradation of insoluble Syn, an effect that was reversed upon the addition of bafilomycin A1. Our results suggest that lysosomal clustering can facilitate the breakdown of protein aggregates. Therefore, compounds that promote lysosomal clustering may offer a promising therapeutic strategy against neurodegenerative diseases characterized by the presence of aggregate-prone proteins.

cell biology↗

The oncogenic Runx3-Myc axis defines p53-deficient osteosarcomagenesis

Osteosarcoma (OS) in human patients is characterized by genetic alteration of TP53. Osteoprogenitor-specific p53-deleted mice (OS mice) have been widely used to study the process of osteosarcomagenesis. However, the molecular mechanisms responsible for the development of OS upon p53 inactivation remain largely unknown. In this study, we detected prominent RUNX3/Runx3 expression in human and mouse p53-deficient OS. Myc was aberrantly upregulated by Runx3 via mR1, a consensus Runx site in the Myc promoter, in a manner dependent on p53 deficiency. Reduction of the Myc level by disruption of mR1 or Runx3 knockdown decreased the tumorigenicity of p53-deficient OS cells and effectively suppressed OS development in OS mice. Furthermore, Runx inhibitors exerted therapeutic effects on OS mice. Together, these results show that p53 deficiency promotes osteosarcomagenesis in human and mouse by allowing Runx3 to induce oncogenic Myc expression.

cancer biology↗