Besides the G12V HRAS mutation used in the transformation experiment to derive the premalignant cell line MCF10AT from MCF10A, the only mutation we detected was PIK3CA H1047R, which is known to be the most common activating mutation in the PIK3CA gene in human cancer [15], [16].
Furthermore, the KRAS and the BRAF proto-oncogenes were analyzed for the most common activating mutations applying pyro-sequencing.
The two most common activating mutations seen in patients are exon 19 deletions and the exon 21 L858R.
The most common activating point mutations are located in codons 12 and 13 of exon 2 of the KRAS gene (in over 90% of PDACs) [ 6, 27, 28].
However, our study showed that the most common activating PIK3CA mutations reported in other cancers were not frequent in gastric cancer.
In systemic mastocytosis, the most common activating mutation in C-KIT D816V, occurs in the catalytic region of the enzyme, and also prevents binding of imatinib.
The most common activating mutations in EGFR, which account for 90% of all EGFR mutations in cases of NSCLC, are exon 19 deletions and the L858R mutation in the tyrosine kinase domain (Table 1) [ 1].
We analyzed exon 15 of BRAF to search for a V600E substitution, the most common activating mutation of BRAF, which is observed at high frequencies in various cancers [ 35].
For example, deletions in EGFR exon 19 and the point mutation L858R in exon 21 are the most common activating mutations and have been predominantly found in females, never smokers, adenocarcinomas and Asian patients (Rosell et al, 2009; Xu et al, 2011).
Although monogenic neonatal diabetes may be caused by mutations in >20 different genes, the most common are activating heterozygous mutations in KCNJ11, encoding the Kir6.2 subunit of the ATP-sensitive K+ channel (KATP channel), which is highly expressed in pancreatic β-cells and brain (1).
