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Title: Comparison of click-capable oxaliplatin and cisplatin derivatives to better understand Pt(II)-induced nucleolar stress
Pt(II) chemotherapeutic complexes have been used as predominant anticancer drugs for nearly fifty years. Currently there are three FDA-approved chemotherapeutic Pt(II) complexes: cisplatin, carboplatin, and oxaliplatin. Until recently, it was believed that all three complexes induced cellular apoptosis through the DNA damage response pathway. Studies within the last decade, however, suggest that oxaliplatin may instead induce cell death through a unique nucleolar stress pathway. Pt(II)-induced nucleolar stress is not well understood and further investigation of this pathway may provide both basic knowledge about nucleolar stress as well as insight for more tunable Pt(II) chemotherapeutics. Through a previous structure-function analysis, it was determined that nucleolar stress induction is highly sensitive to modifications at the 4-position of the 1,2-diaminocyclohexane (DACH) ring of oxaliplatin. Specifically, more flexible and less rigid substituents (methyl, ethyl, propyl) induce nucleolar stress, while more rigid and bulkier substituents (isopropyl, acetamide) do not. These findings suggest that a clickcapable functional group can be installed at the 4-position of the DACH ring while still inducing nucleolar stress. Herein, we report novel click-capable azide-modified oxaliplatin mimics that cause nucleolar stress. Through NPM1 relocalization, fibrillarin redistribution, and gH2AX studies, key differences have been identified between previously studied click-capable cisplatin mimics and these novel click-capable oxaliplatin mimics. These complexes provide new tools to identify cellular targets and localization through post-treatment Cu-catalyzed azide–alkyne cycloaddition and may help to better understand Pt(II)-induced nucleolar stress. To our knowledge, these are the first reported oxaliplatin mimics to include an azide handle, and cis-[(1R,2R,4S) 4-methylazido-1,2-cyclohexanediamine]dichlorido platinum(II) is the first azide-functionalized oxaliplatin derivative to induce nucleolar stress.  more » « less
Award ID(s):
2109255 2022168
PAR ID:
10473703
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Royal Society of Chemistry
Date Published:
Journal Name:
RSC Chemical Biology
Volume:
4
Issue:
10
ISSN:
2633-0679
Page Range / eLocation ID:
785 to 793
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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