CD49f 蛋白表达在 B 淋巴母细胞白血病的遗传亚群中存在差异，在 KMT2A 重排病例中明显降低。

CD49f protein expression varies among genetic subgroups of B lymphoblastic leukemia and is distinctly low in KMT2A-rearranged cases.

机构信息

Department of Pathology & Laboratory Medicine, Hartford Hospital, Hartford, Connecticut.

出版信息

Cytometry B Clin Cytom. 2021 Mar;100(2):243-248. doi: 10.1002/cyto.b.21865. Epub 2020 Jan 2.

DOI:10.1002/cyto.b.21865

PMID:31894899

Abstract

BACKGROUND

CD49f (integrin α6) is a useful marker for minimal residual disease (MRD) detection in B lymphoblastic leukemia and has recently been suggested to mediate infiltration of the central nervous system by leukemic B lymphoblasts. However, data regarding expression of CD49f protein in B lymphoblastic leukemia are limited, and whether CD49f protein expression varies among genetic subgroups of B lymphoblastic leukemia is unknown.

METHODS

CD49f protein expression was characterized by flow cytometry in a series of 40 cases of B lymphoblastic leukemia, which included the genetic subgroups: KMT2A-rerranged, BCR-ABL1+, ETV6-RUNX1+, hypodiploidy, and hyperdiploidy.

RESULTS

Expression of CD49f differed significantly among the five genetic subgroups studied, whether assessed by percentage of blasts positive for the antigen (p = .0001, Kruskal-Wallis) or median fluorescence intensity (MFI) (p = .0001, Kruskal-Wallis). Moreover, the percentage of CD49f+ blasts and MFI of CD49f were significantly lower in KMT2A-rearranged cases than in cases without KMT2A rearrangement (p = .0002 for both, Mann-Whitney).

CONCLUSIONS

CD49f protein expression varies among genetic subgroups of B lymphoblastic leukemia, and is distinctly low in KMT2A-rearranged cases.

摘要

背景

CD49f（整合素α6）是检测 B 淋巴母细胞白血病微小残留病（MRD）的有用标志物，最近有研究表明其介导白血病 B 淋巴母细胞浸润中枢神经系统。然而，关于 B 淋巴母细胞白血病中 CD49f 蛋白表达的数据有限，并且 CD49f 蛋白表达是否在 B 淋巴母细胞白血病的遗传亚组中存在差异尚不清楚。

方法

通过流式细胞术对 40 例 B 淋巴母细胞白血病病例进行了 CD49f 蛋白表达特征分析，这些病例包括遗传亚组：KMT2A 重排、BCR-ABL1+、ETV6-RUNX1+、亚二倍体和高倍体。

结果

无论通过抗原阳性的 blast 百分比（p =.0001，Kruskal-Wallis）还是中位荧光强度（MFI）（p =.0001，Kruskal-Wallis）评估，CD49f 的表达在五种研究的遗传亚组之间均存在显著差异。此外，KMT2A 重排病例中 CD49f+blast 的百分比和 CD49f 的 MFI 明显低于无 KMT2A 重排病例（p =.0002，Mann-Whitney）。