PIK3CA Mutational Status Is Associated with High Glycolytic Activity in ER+/HER2- Early Invasive Breast Cancer: a Molecular Imaging Study Using [<sup>18</sup>F]FDG PET/CT.
Next generation sequencing on a subset of cases with invasive breast cancer and adjacent ductal carcinoma in situ (n=4) showed identical genomic aberrations, including PIK3CA, GATA3, TP53, and MAP2K4 mutations.
Furthermore, we discovered that different types of genetic abnormalities (mutation versus amplification) within the same cancer driver gene (PIK3CA or GATA3) were associated with opposite histologic changes in invasive breast cancer.
The phosphatidylinositol-3-kinase pathway is one of the most commonly altered molecular pathways in invasive breast carcinoma, with phosphatidylinositol-3-kinase catalytic subunit (PIK3CA) mutations in 25% of invasive carcinomas.
The present study reports the evaluation of PIK3CA exon 9 and 20 mutations in 149 invasive breast cancer cases using a validated PCR-high resolution melting assay (PCR-HRM).
Activating point mutations in the phosphatidylinositol-3-kinase catalytic subunit (PIK3CA) are among the most common molecular defects in invasive breast cancer.
To further delineate the molecular evolution of breast tumorigenesis, samples of invasive breast carcinoma with an accompanying in situ component were macro dissected from formalin-fixed paraffin embedded tissue and screened for mutations in PIK3CA exons 7, 9, 20, and AKT1 exon 2.