PIK3CA and PIK3R1 tumor mutational landscape in a pan-cancer patient cohort and its association with pathway activation and treatment efficacy.

ABSTRACT: There is little data concerning the implications of PIK3CA mutations outside of the known hotspots described in ER+/HER2- metastatic breast cancer (mBC). Similarly, PIK3R1 mutations could also lead to activation of PI3K pathway, but are poorly described. We determined the incidence and type of all somatic PIK3CA and PIK3R1 mutations by whole exome sequencing (WES) in a pan-cancer cohort of 1200 patients. Activation of the PI3K pathway was studied using phospho-AKT immunohistochemistry. Associations between PIK3CA/PIK3R1 mutations and response to chemotherapy were studied in mBC cases. We found 141 patients (11.8%) with a PIK3CA and/or PIK3R1 mutation across 20 different cancer types. The main cancer subtype was mBC (45.4%). Eighty-four mutations (62.2%) occurred in the three described hots

SUBMITTER: Tharin Z 

PROVIDER: S-EPMC10024711 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature