Casitas b cell lymphoma‑B (Cbl-b): A new therapeutic avenue for small-molecule immunotherapy

Bioorg Med Chem. 2024 Mar 15:102:117677. doi: 10.1016/j.bmc.2024.117677. Epub 2024 Mar 6.

Abstract

Immunotherapy has revolutionized the area of cancer treatment. Although most immunotherapies now are antibodies targeting membrane checkpoint molecules, there is an increasing demand for small-molecule drugs that address intracellular pathways. The E3 ubiquitin ligase Casitas B cell lymphoma‑b (Cbl-b) has been regarded as a promising intracellular immunotherapy target. Cbl-b regulates the downstream proteins of multiple membrane receptors and co-receptors, restricting the activation of the innate and adaptive immune system. Recently, Cbl-b inhibitors have been reported with promising effects on immune surveillance activation and anti-tumor efficacy. Several molecules have entered phase Ⅰ clinical trials. In this review, the biological rationale of Cbl-b as a promising target for cancer immunotherapy and the latest research progress of Cbl-b are summarized, with special emphasis on the allosteric small-molecule inhibitors of Cbl-b.

Keywords: Allosteric inhibitors; Cbl-b; E3 ligase; Immunotherapy; Intracellular immunotherapy target; Small molecule.

Publication types

  • Review

MeSH terms

  • Adaptor Proteins, Signal Transducing / metabolism
  • Humans
  • Immunotherapy
  • Lymphoma, B-Cell*
  • Proto-Oncogene Proteins c-cbl* / metabolism
  • Ubiquitin-Protein Ligases / metabolism

Substances

  • Proto-Oncogene Proteins c-cbl
  • Adaptor Proteins, Signal Transducing
  • Ubiquitin-Protein Ligases