C-ros sarcoma ROS-receptor tyrosine kinase (ROS1) is located on chromosome 6q22 and encodes a receptor tyrosine kinase (RTK), which is involved in cell growth and proliferation, differentiation and survival. When the ROS1 gene is rearranged, the extracellular region is lost, and the transmembrane region and the intracellular tyrosine kinase region are retained. The rearrangement site mainly occurs in the 32 to 36 exons of the ROS1 gene. In NSCLC, ROS1 gene is mainly fused with SLC34A2, CD74, EZR, SDC4, etc., and continues to activate ROS1 tyrosine kinase domain and downstream signaling pathway, which leads to tumor development.
ROS1 gene break-apart probe uses orange-red dye to label the 5′ end region of the ROS1 gene, and a green dye to label the 3′ end region of the ROS1 gene. ROS1 gene break-apart is able to detect all ROS1 gene rearrangements, avoiding the missed diagnosis caused by a single gene fusion.
ROS1 gene rearrangement mainly occurs in young, non-smoking patients with lung adenocarcinoma. ROS1 gene rearrangement is different from other mutations such as EGFR, KRAS, ALK and so on. The positive rate of ROS1 rearrangement was 1.0%-3.4% in NSCLC and 5.7% in EGFR, KRAS and ALK negative population.
On March 11, 2016, the FDA approved the indication for XALKORI (Crizotinib) in the treatment of ROS1-positive advanced NSCLC. XALKORI (Crizotinib) indication for ROS1-positive advanced NSCLC have been approved in China. Patients with positive ROS1 rearrangement are sensitive to XALKORI (Crizotinib) drugs.
Product size: 100μL FISH probe ( ⬤ | ⬤ ) + Pretreatment reagent (10 tests) + Antifade staining solution DAPI (10 tests).