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Double protein knockdown of cIAP1 and CRABP-II using a hybrid molecule consisting of ATRA and IAPs antagonist
Yukihiro Itoh1, Minoru Ishikawa, Risa Kitaguchi
1Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
Abstract:
Protein knockdown can be achieved by the use of a small molecule that possesses affinity for both the target protein and ubiquitin ligase. We have designed such a degradation-inducing molecule targeting cIAP1 and CRABP-II, which are involved in proliferation of several cancer cell lines and in neuroblastoma growth, respectively. As a CRABP-II-recognizing moiety, all-trans retinoic acid (ATRA, 3), a physiological ligand of CRABP, was chosen. As a cIAP1-recognizing moiety, MV1 (5), which is a cIAP1/cIAP2/XIAP pan-ligand, was chosen. Although cIAP1 itself possesses ubiquitin ligase activity, we expected that its decomposition would be efficiently mediated by related molecules, including cIAP2 and XIAP, which also possess ubiquitin ligase activity. The designed degradation inducer 6, in which ATRA (3) and MV1 (5) moieties are connected via a linker, was synthesized and confirmed to induce efficient degradation of both cIAP1 and CRABP-II. It showed potently inhibited the proliferation of IMR32 cells.
Insights
Researchers developed a novel molecule to target and degrade cancer-related proteins, cIAP1 and CRABP-II. This targeted protein knockdown effectively inhibited neuroblastoma cell proliferation, offering a promising new cancer therapy approach.
Area of Science:
- Biochemistry
- Molecular Biology
- Cancer Research
Background:
- Targeted protein degradation is a key strategy in drug discovery.
- Small molecules can induce degradation by bridging target proteins and ubiquitin ligases.
- cIAP1 and CRABP-II are implicated in cancer cell proliferation and neuroblastoma growth.
Purpose of the Study:
- To design and synthesize a novel small molecule for targeted protein knockdown.
- To investigate the molecule's efficacy in degrading cIAP1 and CRABP-II.
- To evaluate the molecule's impact on cancer cell proliferation, specifically in neuroblastoma.
Main Methods:
- Design of a bifunctional molecule incorporating all-trans retinoic acid (ATRA) and MV1.
- Synthesis of the degradation-inducing molecule (compound 6).
- In vitro assays to confirm degradation of cIAP1 and CRABP-II.
- Cell proliferation assays using IMR32 neuroblastoma cells.
Main Results:
- Successful synthesis of the designed degradation inducer (compound 6).
- Compound 6 efficiently induced the degradation of both cIAP1 and CRABP-II proteins.
- Potent inhibition of IMR32 cell proliferation was observed.
Conclusions:
- The novel small molecule effectively targets and degrades cIAP1 and CRABP-II.
- This targeted degradation leads to significant inhibition of neuroblastoma cell proliferation.
- The developed molecule represents a promising therapeutic strategy for cancers involving these targets.
