For many patients with advanced breast cancer

Alpha isoform selectivity may play a role in the future

PIK3CA is an oncogene that codes for the alpha isoform of PI3K (PI3Kα)1

  • Class I PI3Ks are heterodimers consisting of a p110 catalytic subunit and a p85 regulatory subunit. PIK3CA codes specifically for the alpha isoform of p110

PI3K isoforms play different physiological roles1

The high rate of PIK3CA mutations in HR+ breast cancer suggests that further research is warranted3


  1. Thorpe LM, Yuzugullu H, Zhao JJ. PI3K in cancer: divergent roles of isoforms, modes of activation and therapeutic targeting. Nat Rev Cancer. 2015;15(1):7-24.
  2. Fruman DA, Rommel C. PI3K and cancer: lessons, challenges, and opportunities. Nat Rev Drug Discov. 2014;13(2):140-156.
  3. Al-Sukhun S, Lataifeh I, Al-Sukhun R. Defining the prognostic and predictive role of PIK3CA mutations: sifting through the conflicting data. Curr Breast Cancer Rep. 2016;8:73-79.