Objective: To explore the expression of CD66c (CEACM6) in adult acute leukemia and its significance.
Methods: Acute leukemia cell lines HL-60, K562, LCL721.221 and Jurkat were cultured in vitro. RT-PCR and multi-parameter flow cytometry were applied to analysis of CD66c mRNA and protein expression respectively in the cell lines and patient' s bone marrow leukemic cells. Cytogenetic analysis for 199 bone marrow samples from leukemia patients and Minimal Residual Disease (MRD) detection for 25 CD66c positive B lineage ALL were performed.
Results: (1) CD66c expression both on cell surface and in plasma were negative in all the cell lines. (2) Four of 127 AML (3.15%) (mainly of M2 and M4), and 28 of 79 ALL (35.44%) (all of B linage ALL) were CD66c positive the subtypes of the ALL being common B-ALL (20/54) and pre B-ALL (8/11) including 8 Ph + B-linage ALL. (3) Six-month relapse rate was significantly different between the MRD positive and negative patients. (4) CD66c mRNA was strongly expressed in B-linage ALL. For the cell lines, only the HL60 cells weakly expressed CD66c mRNA.
Conclusion: CD66c expression could be a useful bio-marker for the MRD analysis in ALL, and is closely associated with its transcription level.