In conclusion, FGFR1 amplification occurs in a relevant subgroup of carcinomas of the esophagus and may play a particular role for development of squamous cell cancers.
1) a subset of metastatic lobular breast carcinoma harbors FGFR-1 gene amplification or gains of chromogenic signals; 2) a minor heterogeneity has been observed after matching primary and metastatic carcinomas; 3) in the era of tailored therapies, patients affected by the lobular subtype of breast carcinoma with FGFR1 amplification could be approached to the new target biological therapy such as emerging FGFR-1 inhibitors.
Using SNP array analysis, we found that a region of chromosome segment 8p11-12 containing three genes-WHSC1L1, LETM2, and FGFR1-is amplified in 3% of lung adenocarcinomas and 21% of squamous cell lung carcinomas.
Our results indicate that the reciprocal relationship in gene expression between FGFR1 and FGFR3 in colorectal tissue plays an important role in the progression of the carcinomas to malignancy.
In addition, the Ki-67 labeling index showed extremely high mitogenic activity in embryonal carcinoma, yolk sac tumor, and choriocarcinoma, which are precisely the carcinomas with the highest expressions of FGF8, FGF4, and FGFR1.