E-cadherin destabilization accounts for the pathogenicity of missense mutations in hereditary diffuse gastric cancer.

TitleE-cadherin destabilization accounts for the pathogenicity of missense mutations in hereditary diffuse gastric cancer.
Publication TypeJournal Article
Year of Publication2012
AuthorsSimões-Correia J, Figueiredo J, Lopes R, Stricher F, Oliveira C, Serrano L, Seruca R
JournalPLoS One
Date Published2012
KeywordsAlgorithms, Amino Acid Sequence, Animals, Cadherins, CHO Cells, Cricetinae, Cricetulus, Humans, Models, Molecular, Molecular Sequence Data, Mutation, Missense, Stomach Neoplasms

E-cadherin is critical for the maintenance of tissue architecture due to its role in cell-cell adhesion. E-cadherin mutations are the genetic cause of Hereditary Diffuse Gastric Cancer (HDGC) and missense mutations represent a clinical burden, due to the uncertainty of their pathogenic role. In vitro and in vivo, most mutations lead to loss-of-function, although the causal factor is unknown for the majority. We hypothesized that destabilization could account for the pathogenicity of E-cadherin missense mutations in HDGC, and tested our hypothesis using in silico and in vitro tools. FoldX algorithm was used to calculate the impact of each mutation in E-cadherin native-state stability, and the analysis was complemented with evolutionary conservation, by SIFT. Interestingly, HDGC patients harbouring germline E-cadherin destabilizing mutants present a younger age at diagnosis or death, suggesting that the loss of native-state stability of E-cadherin accounts for the disease phenotype. To elucidate the biological relevance of E-cadherin destabilization in HDGC, we investigated a group of newly identified HDGC-associated mutations (E185V, S232C and L583R), of which L583R is predicted to be destabilizing. We show that this mutation is not functional in vitro, exhibits shorter half-life and is unable to mature, due to premature proteasome-dependent degradation, a phenotype reverted by stabilization with the artificial mutation L583I (structurally tolerated). Herein we report E-cadherin structural models suitable to predict the impact of the majority of cancer-associated missense mutations and we show that E-cadherin destabilization leads to loss-of-function in vitro and increased pathogenicity in vivo.

Alternate JournalPLoS ONE
PubMed ID22470475