Targeted Mutational Profiling in Metastatic Breast Cancer

We conducted the assessment of TERT promoter hotspot loci, TP53 (exons 2 to 11), PIK3CA (exons 9 and 20), HRAS (exon 3), and BRAF (exons 11 and 15) hotspot mutations in 16 MBCs with insufficient DNA yield by Sanger sequencing. In addition, as TERT promoter region is usually poorly covered by exome sequencing, TERT promoter hotspot mutations were assessed by Sanger sequencing in the 27 MBCs subjected to WES. PCR amplification of the selected genes was performed using the AmpliTaq Gold 360 Master Mix kit (Life Technologies, ThermoFisher Scientific) using previously described primers^{16 (link),24 (link),60 (link)} (Supplementary Table S4). PCR fragments were cleaned using ExoSAP It (ThermoFisher Scientific) and Sanger sequenced as previously described^{15 (link),16 (link)}.