PIK3CA Mutation Analysis in Iranian Patients with Gastric Cancer

BACKGROUND: Aberrant activation of phosphatidylinositol-3 kinases (PI3K)/AKT/mTOR (mammalian target of rapamycin) pathway is a critical event during gastric cancer progression. Selective function of AKT inhibitor AZD5363 in PI3KCA mutant gastric cancer necessitates the assessment of PI3KCA mutations in these patients. METHODS: The study included 100 patients with gastric cancer who underwent surgical resection at Imam Reza Hospital, Tehran, Iran, between January 2009 and December 2016. Mutations in codon 1047 of PIK3CA were evaluated by tetra-primer ARMS-PCR and direct sequencing methods. RESULTS: We detected p.H1047R and p.H1047L in eight and three samples, respectively. Also, a significant association was found between PIK3CA mutations and lymphatic invasion. Kaplan-Meier analysis demonstrated no significant differences in overall survival between patients with and without mutations. CONCLUSION: Our study detected gain-of-function mutations in exon 20 of PI3KCA gene in 11% of gastric cancer patients. Future studies are needed to assess the mutation rate in other regions of this gene to find eligible patients for targeted therapies.