title: Chemical modification and organelle-specific localization of orlistat-like natural-product-based probes.
abstract: Orlistat, also known as tetrahydrolipstatin (THL), is an FDA-approved anti-obesity drug with potential anti-cancer activity. Previously, we developed a chemical proteomic approach, based on the Orlistat-like probe (1a) for large-scale identification of unknown cellular targets of Orlistat in human hepatocytes. In this article, we report the chemical synthesis and biological evaluation of an expanded set of Orlistat-like compounds, with the intention to further dissect and manipulate potential cellular targets of Orlistat. In doing so, we carried out proteome-wide activity-based profiling and large-scale pull-down/LCMS analysis of these compounds in live HepG2 cells, and successfully identified many putative cellular targets for Orlistat and its structural analogues. By qualitatively assessing the spectra counts of potential protein hits against each of the seventeen Orlistat analogues, we obtained both common and unique targets of these probes. Our results revealed that subtle structural modifications of Orlistat led to noticeable changes in both the cellular potency and target profiles of the drug. In order to further improve the cellular activity of Orlistat, we successfully applied the well-established AGT/SNAP-tag technology to our cell-permeable, benzylguanine (BG)-containing Orlistat variant (4). We showed that the drug could be delivered and effectively retained in different sub-cellular organelles of living cells. This strategy may provide a general and highly effective chemical tool for the potential sub-cellular targeting of small molecule drugs.
authors: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
authors: Peng-Yu
authors: PY
authors: Yang
authors: Kai
authors: K
authors: Liu
authors: Chongjing
authors: C
authors: Zhang
authors: Grace Y J
authors: GY
authors: Chen
authors: Yuan
authors: Y
authors: Shen
authors: Mun Hong
authors: MH
authors: Ngai
authors: Martin J
authors: MJ
authors: Lear
authors: Shao Q
authors: SQ
authors: Yao
mesh_terms: D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001688:Biological Products / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D015195:Drug Design; D004354:Drug Screening Assays, Antitumor; D056945:Hep G2 Cells; D006801:Humans; D007783:Lactones / Q000737:chemistry*; D015394:Molecular Structure; D015388:Organelles / Q000187:drug effects / Q000378:metabolism*; D000077403:Orlistat; D013237:Stereoisomerism; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D001688:Biological Products; D007783:Lactones; D000077403:Orlistat