SAR405

SAR405 is a Vps34 inhibitor (IC₅₀=1.2 nM),SAR405 inhibits autophagy caused by mTOR inhibition^[1，2].

Treatment of RKO colorectal cancer cells with SAR405 showed large translucent vacuoles 16 h after treatment with SAR405 at 10 µM. These vacuoles were positive for the lysosomotropic dye Lysotracker and were also decorated with the lysosomal membrane protein Lamp1^[1]. Under normal growth conditions, the GFP-FYVE probe appeared as green spots,This relocalization of the GFP-FYVE indicated that SAR405 inhibits PtdIns3P formation. By quantifying the positive cells, it can determine an IC₅₀ of 27 nM^[1]. Inhibition of autophagy by SAR405, in general, or of the autophagy-inducing class III PtdIns3K complex, in particular, sensitized both sensitive and resistant urothelial carcinoma cells to cisplatin-induced cytotoxic effects^[3]. Chromosome missegregation induced by reverse transcriptase can produce excess protein subunit protein complex imbalance proteotoxic stress and autophagy activation, which may contribute to the removal of misfolded or redundant proteins, afA and SAR405 reverse the reverse-dependent nuclear phagocytosis flux^[4]. Actin domain formation was repressed by the depletion of PI3P by SAR405, an inhibitor of the class III PI3 kinase, Vps34, and by the use of diabetic model cells, in which PI3P was depleted. SAR405 did not affect the phosphorylation level of Akt, and the transcriptional regulation of gluconeogenic and cholesterol synthetic genes after insulin treatment[6]. Deregulation of autophagy in normal fibroblasts, either by inhibition with autophagy inhibitor, SAR405, or activation with TGF-β1, induced fibroblast activation and senescence: In response to TGF-β1, autophagy was induced prior to the development of the activated and senescent phenotypes^[7].

Local delivery of SAR405 to the BLA impaired freezing behaviors at 24 hours, with no difference was observed at 3 hours. In addition, SAR405 administation had no effect on memory retrival test^[5].

References:
[1]. Ronan B, Flamand O, et,al. A highly potent and selective Vps34 inhibitor alters vesicle trafficking and autophagy. Nat Chem Biol. 2014 Dec;10(12):1013-9. doi: 10.1038/nchembio.1681. Epub 2014 Oct 19. PMID: 25326666.
[2]. Pasquier B. SAR405, a PIK3C3/Vps34 inhibitor that prevents autophagy and synergizes with MTOR inhibition in tumor cells. Autophagy. 2015 Apr 3;11(4):725-6. doi: 10.1080/15548627.2015.1033601. PMID: 25905679; PMCID: PMC4502822.
[3]. SchlÜtermann D, Skowron MA, et,al. Targeting urothelial carcinoma cells by combining cisplatin with a specific inhibitor of the autophagy-inducing class III PtdIns3K complex. Urol Oncol. 2018 Apr;36(4):160.e1-160.e13. doi: 10.1016/j.urolonc.2017.11.021. Epub 2017 Dec 21. PMID: 29276062.
[4]. An H, Harper JW. Systematic analysis of ribophagy in human cells reveals bystander flux during selective autophagy. Nat Cell Biol. 2018 Feb;20(2):135-143. doi: 10.1038/s41556-017-0007-x. Epub 2017 Dec 11. PMID: 29230017; PMCID: PMC5786475.
[5]. Li K, Chen HS, et,al.SAR405, a Highly Specific VPS34 Inhibitor, Disrupts Auditory Fear Memory Consolidation of Mice via Facilitation of Inhibitory Neurotransmission in Basolateral Amygdala. Biol Psychiatry. 2019 Feb 1;85(3):214-225. doi: 10.1016/j.biopsych.2018.07.026. Epub 2018 Aug 16. Erratum in: Biol Psychiatry. 2019 Nov 15;86(10):801. PMID: 30253884.
[6]. Kano F, Murata M. Phosphatidylinositol-3-phosphate-mediated actin domain formation linked to DNA synthesis upon insulin treatment in rat hepatoma-derived H4IIEC3 cells. Biochim Biophys Acta Mol Cell Res. 2019 May;1866(5):793-805. doi: 10.1016/j.bbamcr.2019.02.005. Epub 2019 Feb 8. PMID: 30742930.
[7]. Tan ML, Parkinson EK, et,al. Autophagy is deregulated in cancer-associated fibroblasts from oral cancer and is stimulated during the induction of fibroblast senescence by TGF-β1. Sci Rep. 2021 Jan 12;11(1):584. doi: 10.1038/s41598-020-79789-8. Erratum in: Sci Rep.