Indirubin derivatives: a patent review (2010 – present)

Abstract

Introduction: Indirubins are bisindole alkaloids naturally occurring in indigo-bearing plants or in mollusks from the Muricidae family. They belong to the rather small family of indigoids, which has nevertheless found an extreme importance in the fields of dyes and medicinal chemistry. Indirubin has been found to be the active ingredient of a traditional Chinese Medicine used to treat the symptoms of leukemia. Further biological explorations revealed the ability of indirubin to bind cyclin-dependent kinases and 6-bromoindirubin, extracted from mollusks, to bind glycogen synthase kinase-3. The high affinity displayed by the two natural products has opened a vast field of research and triggered the development of hundred of derivatives with biological activities.

Areas covered: The traditional use of indirubin for the treatment of leukemia has prompted different research groups to study the cytotoxic effect of indirubin derivatives on both solid tumors and leukemia. Moreover, the affinity of indirubins for kinases also allowed the exploration of their activity towards stem cells.

Expert opinion: The derivatives presented are in accordance with first discoveries and establish the close relation between activity and kinase inhibition. New derivatives have been patented and new interferences in signaling pathways are described. However, few in vivo studies have been performed and more efficient solutions are needed to unravel the major issue of solubility.

Keywords:

• cancer
• derivatives
• indirubin
• kinases
• leukemia
• patents
• stem cells

Acknowledgement

N Gaboriaud-Kolar and K Vougogiannopoulou contributed equally to this work.

Declaration of interest

The authors were supported by University of Athens. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Notes

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