PI3K pathway activation results in low efficacy of both trastuzumab and lapatinib
[Paper-level Aggregated] PMCID: PMC3141770
Evidence Type(s): Oncogenic, Prognostic
Justification: Oncogenic: The presence of PIK3CA mutations, specifically H1047R and E542K, is associated with tumorigenesis, as indicated by their occurrence in tumor samples and the context of their mutation hotspots. Prognostic: The study suggests a correlation between PIK3CA mutations and PTEN expression loss, which may have implications for patient outcomes, particularly since a significant portion of patients with the H1047R mutation also exhibited PTEN loss.
Gene→Variant (gene-first): PIK3CA(5290):E542K PIK3CA(5290):H1047R PTEN(5728):T1052A
Genes: PIK3CA(5290) PTEN(5728)
Variants: E542K H1047R T1052A