The immunophenotype of acute promyelocytic leukemia (APL): an ECOG study.
In 452 adult patients with de novo acute myeloid leukemia (AML), a series of 22 monoclonal antibodies was used to identify immunophenotypic characteristics of acute promyelocytic leukemia (APL) as compared to other AMLs (groups FAB M1/M2 and M4/M5). Only those patients with FAB M3 cytology were included in the analysis for which APL was confirmed by the presence of the t(15;17) cytogenetic aberration and the detection of the PML/RAR alpha gene fusion transcript by PCR amplification (35 cases). Significantly fewer APL blast cells were positive for the stem cell antigen, CD34 (p = 0.0001) as well as for HLA-DR (p < 0.0001). With respect to myeloid antigens, APLs less frequently expressed the myelomonocytic antigens, CD11b (p = 0.0001) and CD14 (p = 0.0013), whereas expression of CD33, a pan-myeloid marker, was more frequent in APL (p = 0.0001). CD15, the X-hapten carbohydrate structure (lacto-N-fucopentaose-III), typically expressed at the maturation stage of normal promyelocytes, was found to be sialylated on APL blasts as recognized by differential binding of the anti-CD15 antibodies, VIM-D5 (non-sialylated CD15) and VEP-9 (sialylated CD15). Expression of the T-cell associated CD7 antigen was rarer on APL than non-APL cells (p = 0.0001), as was that of the multidrug resistance P-glycoprotein (p = 0.0038). Marginal correlations existed between antigen profile (particularly CD2) and the type of PML/RAR alpha transcripts. In addition to its unique genotypic features, these data establish APL as a distinct immunophenotypic entity.
Department of Oncology, Montefiore and Albert Einstein Cancer Center, Bronx, New York.
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Paietta
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Andersen
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Gallagher
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Bennett
J
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Yunis
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Cassileth
J
J
Rowe
P H
PH
Wiernik
D000328:Adult; D000911:Antibodies, Monoclonal; D015703:Antigens, CD / Q000032:analysis; D000951:Antigens, Neoplasm / Q000032:analysis; D006801:Humans; D016130:Immunophenotyping; D007948:Leukemia, Monocytic, Acute / Q000276:immunology / Q000473:pathology; D015470:Leukemia, Myeloid, Acute / Q000276:immunology / Q000473:pathology; D015479:Leukemia, Myelomonocytic, Acute / Q000276:immunology / Q000473:pathology; D015473:Leukemia, Promyelocytic, Acute / Q000276:immunology* / Q000473:pathology
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000951:Antigens, Neoplasm