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The accumulation of toxic protein aggregates in multiple neurodegenerative diseases is associated with defects in the macroautophagy/autophagy-lysosome pathway. The amelioration of disease phenotypes across multiple models of neurodegeneration can be achieved through modulating the master regulator of lysosome function, TFEB (transcription factor EB). Using a novel multi-parameter high-throughput screen for cytoplasmic:nuclear translocation of endogenous TFEB and the related transcription factor TFE3, we screened the Published Kinase Inhibitor Set 2 (PKIS2) library as proof of principle and to identify kinase regulators of TFEB and TFE3. Given that TFEB and TFE3 are responsive to cellular stress we have established assays for cellular toxicity and lysosomal function, critical to ensuring the identification of hit compounds with only positive effects on lysosome activity. In addition to AKT inhibitors which regulate TFEB localization, we identified a series of quinazoline-derivative compounds that induced TFEB and TFE3 translocation. A novel series of structurally-related analogs was developed, and several compounds induced TFEB and TFE3 translocation at higher potency than previously screened compounds. KINOMEscan and cell-based KiNativ kinase profiling revealed high binding for the PRKD (protein kinase D) family of kinases, suggesting good selectivity for these compounds. We describe and utilize a cellular target-validation platform using CRISPRi knockdown and orthogonal PRKD inhibitors to demonstrate that the activity of these compounds is independent of PRKD inhibition. The more potent analogs induced subsequent upregulation of the CLEAR gene network and cleared pathological HTT protein in a cellular model of proteinopathy, demonstrating their potential to alleviate neurodegeneration-relevant phenotypes. Abbreviations: AD: Alzheimer disease; AK: adenylate kinase; CLEAR: coordinated lysosomal expression and regulation; CQ: chloroquine; HD: Huntington disease; PD: Parkinson disease; PKIS2: Published Kinase Inhibitor Set 2; PRKD: protein kinase D; TFEB: transcription factor EB. [ABSTRACT FROM AUTHOR]

Therapeutic strategies based on a specific oncogenic target are better justified when elimination of that particular oncogene reduces tumorigenesis in a model organism. One such oncogene, Musashi-1 (Msi-1), regulates translation of target mRNAs and is implicated in promoting tumorigenesis in the colon and other tissues. Msi-1 targets include the tumor suppressor adenomatous polyposis coli (Apc), a Wnt pathway antagonist lost in ***80% of all colorectal cancers. Cell culture experiments have established that Msi-1 is a Wnt target, thus positioning Msi-1 and Apc as mutual antagonists in a mutually repressive feedback loop. Here, we report that intestines from mice lacking Msi-1 display aberrant Apc and Msi-1 mutually repressive feedback, reduced Wnt and Notch signaling, decreased proliferation, and changes in stem cell populations, features predicted to suppress tumorigenesis. Indeed, mice with germline Apc mutations (ApcMin) or with the Apc1322T truncation mutation have a dramatic reduction in intestinal polyp number when Msi-1 is deleted. Taken together, these results provide genetic evidence that Msi-1 contributes to intestinal tumorigenesis driven by Apc loss, and validate the pursuit of Msi-1 inhibitors as chemo-prevention agents to reduce tumor burden. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to examine the effects of moisture, as a skin microclimate variable, at the skin-support surface interface on repeated measures of skin erythema, stratum corneum hydration and skin temperature at pressure-prone areas of healthy adults., Design: Quasi-experimental repeated measures study., Subjects and Setting: Forty-eight healthy adults participated in a single center-controlled study conducted in a simulated hospital setting in an urban setting (Melbourne, Australia). This research project was conducted from November 2021 to June 2022., Methods: The effects of moisture and intermittent pressure-loading on skin overlying the sacrum, heels, and elbows were investigated. Participants followed a standardized immobilization protocol of 60 minutes, with 10-minute brief pressure off-loading, in the semi-recumbent position on a standard hospital bed/mattress. The intervention comprised laying with the sacrum in contact with an absorbent pad saturated with normal saline; control skin sites (elbows and heels) were not exposed to the moistened absorbent pad. Skin measures were obtained consecutively at each anatomical testing site upon brief off-loading. Linear mixed models (LMMs) were used to compare skin parameters over time and between conditions., Results: Differences in stratum corneum hydration scores between control and intervention conditions at the sacrum were significant (P = .001). Differences in erythema and skin temperature scores between control and intervention conditions at the sacrum did not significantly differ; however, significant changes in skin temperature (P = .025) at the sacrum were observed at the 10-minute measurement intervals over 1 hour in the sample, suggesting change in skin temperature over time. No participant displayed non-blanching erythema as a subjective indicator of skin injury in any of the testing conditions., Conclusions: Skin moisture/wetness, over a period of 1 hour, does not appear to impact erythema and skin temperature at the sacrum. In contrast, the introduction of moisture at the sacrum significantly increases sacral stratum corneum hydration. Study findings suggest that more frequent monitoring cycles of wet sacral skin may be required to identify moisture-associated skin changes., Competing Interests: The authors have no financial or other sources of conflict of interest relating to the submission of this manuscript. The work described has not been published previously., (Copyright © 2024 by the Wound, Ostomy, and Continence Nurses Society.)