ROS1 IHC was performed on a selected cohort of 33 lung adenocarcinoma whole tissue specimens with alterations in the EGFR (n = 5), KRAS (n = 5), ERBB2 (HER2) (n = 3), ROS1 (n = 6), ALK (n = 5), and RET (n = 3) genes and pan-negative (n = 6) detected by reverse transcriptase-polymerase chain reaction (RT-PCR) and FISH.
A literature review identified a ROS1 fusion in 2.54% of the patients with lung adenocarcinoma and even higher frequencies in spitzoid neoplasms and inflammatory myofibroblastic tumors.
Activated anaplastic lymphoma kinase (ALK) and ROS1 tyrosine kinases, through gene fusions, have been found in lung adenocarcinomas and are highly sensitive to selective kinase inhibitors.
ALK and ROS1 are prognostic and predictive tumor markers in non-small cell lung carcinoma (NSCLC), which are more often found in lung adenocarcinomas as with other oncogenes such as EGFR, KRAS, or C-MET.
As lung cancers with ROS1 rearrangements comprise only 1-3% of lung adenocarcinomas, patients with such tumors must be identified to gain optimal benefit from molecular therapy.
Based on multiple logistic regression analysis, we determined that female sex, cribriform structure and the presence of psammoma body were the three most powerful indicators of ROS1 rearrangement, and we have developed a predictive model for the presence of ROS1 rearrangements in lung adenocarcinomas.
Chromosomal rearrangements of ALK and ROS1 genes in non-small cell lung carcinoma (NSCLC) define a molecular subgroup of lung adenocarcinoma (ADC) that is amenable to targeted therapy with tyrosine kinase inhibitors (TKIs) crizotinib.
Collectively, these data suggest that each of these two ROS1-fusion genes acts as a driver for the pathogenesis of lung adenocarcinoma in vivo The TG mice developed in this study are expected to serve as valuable tools for exploring novel therapeutic agents against ROS1-fusion-positive lung cancer.
Consecutive lung adenocarcinoma specimens (n = 176) 'double-negative' (wild-type EGFR and KRAS) were tested for ALK rearrangements/copy number alterations and for ALK, c-MET and ROS1 protein expression using automated standardized protocols.
Crizotinib was highly active at treating lung cancer in patients with a ROS1 rearrangement, suggesting that patients with lung adenocarcinomas should be tested for ROS1.