Structure, Functions, and Implications of Selected Lipocalins in Human Disease

Int J Mol Sci. 2024 Apr 12;25(8):4290. doi: 10.3390/ijms25084290.

Abstract

The lipocalin proteins are a large family of small extracellular proteins that demonstrate significant heterogeneity in sequence similarity and have highly conserved crystal structures. They have a variety of functions, including acting as carrier proteins, transporting retinol, participating in olfaction, and synthesizing prostaglandins. Importantly, they also play a critical role in human diseases, including cancer. Additionally, they are involved in regulating cellular homeostasis and immune response and dispensing various compounds. This comprehensive review provides information on the lipocalin family, including their structure, functions, and implications in various diseases. It focuses on selective important human lipocalin proteins, such as lipocalin 2 (LCN2), retinol binding protein 4 (RBP4), prostaglandin D2 synthase (PTGDS), and α1-microglobulin (A1M).

Keywords: A1M; LCN2; PTGDS; RBP4; cancer; carrier proteins; human disease; lipocalins; structure; transport proteins.

Publication types

  • Review

MeSH terms

  • Animals
  • Humans
  • Intramolecular Oxidoreductases*
  • Lipocalins* / chemistry
  • Lipocalins* / genetics
  • Lipocalins* / metabolism
  • Neoplasms / metabolism
  • Structure-Activity Relationship

Substances

  • Lipocalins
  • prostaglandin R2 D-isomerase
  • Intramolecular Oxidoreductases

Grants and funding

RW is supported by the German Research Foundation (grants WE2554/13-1, WE2554/15-1, and WE 2554/17-1), the Deutsche Krebshilfe (grant 70115581), and the Interdisciplinary Centre for Clinical Research within the faculty of Medicine at RWTH Aachen University (grant PTD 1-5). The funders had no role in the design of this article or in the decision to publish it.