Lymphatic disorders caused by mosaic, activating KRAS variants respond to MEK inhibition

Sheppard, S.E., March, M.E., Seiler, C., Matsuoka, L.S., Kim, S.E., Kao, C., Rubin, A.I., Battig, M.R., Khalek, N., Schindewolf, E., O'Connor, N., Pinto, E., Priestley, J.R., Sanders, V.R., Niazi, R., Ganguly, A., Hou, C., Slater, D., Frieden, I.J., Huynh, T., Shieh, J.T., Krantz, I.D., Guerrero, J.C., Surrey, L.F., Biko, D.M., Laje, P., Castelo-Soccio, L., Nakano, T.A., Snyder, K., Smith, C.L., Li, D., Dori, Y., Hakonarson, H.
JCI insight   8(9): (Journal)
Registered Authors
Seiler, Christoph
Cardiology, Cardiovascular disease, Genetics, Molecular biology, Molecular genetics
MeSH Terms
  • Animals
  • Endothelial Cells/metabolism
  • Humans
  • Mitogen-Activated Protein Kinase Kinases/metabolism
  • Phosphorylation
  • Proto-Oncogene Proteins p21(ras)*/genetics
  • Proto-Oncogene Proteins p21(ras)*/metabolism
  • Zebrafish*
  • Zebrafish Proteins/genetics
  • Zebrafish Proteins/metabolism
37154160 Full text @ JCI Insight
Central conducting lymphatic anomaly (CCLA) due to congenital maldevelopment of the lymphatics can result in debilitating and life-threatening disease with limited treatment options. We identified 4 individuals with CCLA, lymphedema, and microcystic lymphatic malformation due to pathogenic, mosaic variants in KRAS. To determine the functional impact of these variants and identify a targeted therapy for these individuals, we used primary human dermal lymphatic endothelial cells (HDLECs) and zebrafish larvae to model the lymphatic dysplasia. Expression of the p.Gly12Asp and p.Gly13Asp variants in HDLECs in a 2‑dimensional (2D) model and 3D organoid model led to increased ERK phosphorylation, demonstrating these variants activate the RAS/MAPK pathway. Expression of activating KRAS variants in the venous and lymphatic endothelium in zebrafish resulted in lymphatic dysplasia and edema similar to the individuals in the study. Treatment with MEK inhibition significantly reduced the phenotypes in both the organoid and the zebrafish model systems. In conclusion, we present the molecular characterization of the observed lymphatic anomalies due to pathogenic, somatic, activating KRAS variants in humans. Our preclinical studies suggest that MEK inhibition should be studied in future clinical trials for CCLA due to activating KRAS pathogenic variants.
Genes / Markers
Show all Figures
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes