Curtailing FGF19's mitogenicity by suppressing its receptor dimerization ability

Jianlou Niu1, Jing Zhao1,2, Jiamin Wu1

  • 1School of Pharmaceutical Science, Wenzhou Medical University, Wenzhou, 325035 Zhejiang, China.

Insights

Fibroblast Growth Factor 19 (FGF19) analogs were engineered to reduce tumor risk while maintaining therapeutic benefits for diabetes and liver disease. These nonmitogenic variants show promise for safer FGF19-based treatments.

Area of Science:

  • Biochemistry
  • Endocrinology
  • Hepatology

Background:

  • Fibroblast Growth Factor 19 (FGF19) regulates bile acid homeostasis and improves metabolic parameters.
  • FGF19 shows therapeutic potential for type 2 diabetes and liver diseases but carries a tumorigenic risk.
  • Mitogenic activity of FGF19 is linked to its receptor dimerization, a potential driver of adverse effects.

Purpose of the Study:

  • To engineer nonmitogenic FGF19 variants with retained therapeutic activities.
  • To reduce the tumorigenic potential of FGF19 for clinical applications.
  • To develop safer and more effective FGF19 analogs for metabolic and liver diseases.

Main Methods:

  • Engineered FGF19 variants with reduced binding affinity to FGFR and/or coreceptors (βklotho, heparan sulfate).
  • Assessed mitogenic activity of FGF19 variants.
  • Evaluated glycemic control and bile acid regulatory functions in WT and db/db mice.

Main Results:

  • Generated FGF19 variants (FGF19ΔFGFR, FGF19ΔKLB, FGF19ΔHBS) with significantly reduced mitogenic potential.
  • These variants maintained the glucose-lowering and bile acid-regulating efficacy of wild-type FGF19 (FGF19WT).
  • Pharmacological assays confirmed comparable metabolic benefits without increased mitogenicity.

Conclusions:

  • Nonmitogenic FGF19 variants can be developed by modulating FGFR dimerization.
  • Engineered FGF19 analogs retain beneficial metabolic and bile acid effects while losing mitogenic activity.
  • This strategy offers a pathway for developing safer FGF19-based therapeutics for diabetes and liver conditions.

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