Open AccessFibroblast growth factor receptor‐1 protein expression is associated with prognosis in estrogen receptor‐positive/human epidermal growth factor receptor‐2‐negative primary breast cancer
Author(s) -
Tomiguchi Mai,
Yamamoto Yutaka,
YamamotoIbusuki Mutsuko,
GotoYamaguchi Lisa,
Fujiki Yoshitaka,
Fujiwara Saori,
Sueta Aiko,
Hayashi Mitsuhiro,
Takeshita Takashi,
Inao Touko,
Iwase Hirotaka
Publication year - 2016
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/cas.12897
Subject(s) - fibroblast growth factor receptor , breast cancer , estrogen receptor , cancer research , medicine , fibroblast growth factor receptor 4 , receptor , biology , epidermal growth factor receptor , cancer , endocrinology , oncology , fibroblast growth factor
Recently, research into the development of new targeted therapies has focused on specific genetic alterations to create advanced, more personalized treatment. One of the target genes, fibroblast growth factor receptor‐1 ( FGFR 1 ), has been reported to be amplified in estrogen receptor ( ER )‐positive subtype breast cancer, and is considered one possible mechanism of endocrine resistance through cross‐talk between ER and growth factor receptor signaling. We performed a comprehensive analysis of FGFR 1 at the levels of gene copy number, transcript and protein expression, and examined the relationships between FGFR 1 status and clinicopathological parameters, including prognosis in 307 ER ‐positive/ HER 2‐negative primary breast cancer patients treated with standard care at our institute. Most notably, a high level of FGFR 1 protein expression was observed in 85 patients (27.7%), and was positively associated with invasive tumor size ( P = 0.039). Furthermore, univariate analysis revealed that high FGFR 1 protein expression was significantly correlated with poor relapse‐free survival rate ( P = 0.0019, HR : 2.63, 95% confidence interval: 1.17–5.98), and showed a tendency towards an increase in recurrent events if the observation period extended beyond the 5 years of the standard endocrine treatment term. FGFR 1 gain/amplification was found in 43 (14.0%) patients, which was only associated with higher nuclear grade ( P = 0.010). No correlation was found between FGFR 1 mRNA expression levels and any clinicopathological factors. Overall, the level of FGFR 1 protein expression may be a biomarker of ER ‐positive/ HER 2‐negative primary breast cancer with possible resistance to standard treatment, and may be a useful tool to identify more specific patients who would benefit from FGFR ‐1 targeted therapy.