Prognostic Value of the Expression of Receptor Tyrosine Kinase-Like Orphan Receptor 1 (ROR-1) in Chronic Lymphocytic Leukemia
Abstract
Background: The transmembrane receptor tyrosine kinase-like orphan receptor 1 (ROR1) has acted on the causation and sustentation of mature B cell lymphomagenesis for chronic lymphocytic leukemia (CLL) cells. The aim of this study was to show whether there is a relationship between the level of ROR1 surface expression in CLL cells and disease findings.
Materials and Methods: The level of ROR1 cell surface expression was determined in accordance with the flow cytometric analysis of CLL patients at the first diagnosis time. 2 groups were formed according to the high and low ROR1 levels. The cut-off point to the ROR1 level was calculated for advanced-stage disease by using receiver operating characteristic (ROC) curves. A two-sided p-value <0,05 was considered statistically significant.
Results: 108 CLL cases with a median age of 60 were enrolled. The median percentage of ROR1 cell surface marker positivity in the CD5/CD19 positive leukemic cell was 62%. The CLL cases with high ROR1 levels have thrombocytopenia (p=0.042), anemia (p=0.028), and high beta 2 microglobulin value ≥3 mg/dL (p=0.002) and the need for first-line treatment (p=0.043).
Conclusion: The poor prognostic parameters such as splenomegaly, anemia, higher beta 2 microglobulin levels, intermediate/advanced RAİ stage disease, and need for first-line treatment had associated high-level ROR 1 expression of our CLL patients. It needs to be investigated for its effect on predicting disease burden and aggressiveness with more comprehensive studies on ROR1 expression levels in CLL cases.