Cancer genomics and genetics of FGFR2 (Review)

FGFR2 gene encodes FGFR2b in epithelial cells, and FGFR2c in mesenchymal cells. FGFR2b is a high affinity receptor for FGF1, FGF3, FGF7, FGF10 and FGF22, while FGFR2c for FGF1, FGF2, FGF4, FGF6, FGF9, FGF16 and FGF20. Here genomics and genetics of FGFR2, and therapeutics targeted to FGFR2 will be reviewed. Single nucleotide polymorphisms (SNPs) of FGFR2 are associated with increased risk of breast cancer. Gene amplification or missense mutation of FGFR2 occurs in gastric cancer, lung cancer, breast cancer, ovarian cancer, and endometrial cancer. Genetic alterations of FGFR2 induce aberrant FGFR2 signaling activation due to release of FGFR2 from autoinhibition, or creation of FGF signaling autocrine loop. Class switch of FGFR2b to FGFR2c is associated with more malignant phenotype. FGF and canonical WNT signals synergize during mammary carcinogenesis, but counteract during osteogenesis and adipogenesis. Among PD173074, SU5402, and AZD2171 functioning as FGFR inhibitors, AZD2171 is the most promising anti-cancer drug. Cancer genomics and genetics are utilized to predict cancer-driving pathway for therapeutic optimization. FGFR2ome is defined as a complete data set of SNP, copy number variation (CNV), missense mutation, gene amplification, and predominant isoform of FGFR2. FGFR2ome analyses in patients with several tumor types among various populations should be carried out to establish integrative database of FGFR2 for the rational clinical application of FGFR2-targeted cancer therapy.