The uniqueness of morphological features of pure erythroid leukemia in myeloid neoplasm with erythroid predominance: A reassessment using criteria revised in the 2016 World Health Organization classification

An unusual case of pure erythroid leukemia with normal karyotype and NPM1 mutation

Pure erythroid leukemia (PEL) is an extremely rare subtype of acute myeloid leukemia (AML). Although not specific, PEL is almost uniformly associated with complex karyotype and TP53 mutations. Given the rarity of the disease, our understanding of its cytogenetic and molecular features deems incomplete. We aim to complement existing literature by presenting an unusual case of PEL. The case is comprehensively worked up with multiple modalities. We present for the first time a case of PEL with unusual cytogenetic and molecular features: normal karyotype with absence of TP53 mutations and presence of NPM1 and NRAS mutations. This is a valuable addition to literature, expanding our understanding of molecular and cytogenetic spectra of PEL.

A Novel Chalcone Derivative Regulates the Expression and Phosphorylation of ERK1/2 by Inhibiting Fli-1 Promoter Activity for Preventing the Malignant Progression of Erythroleukemia

Acute erythroleukemia is a rare form of acute myeloid leukemia recognized by its distinct phenotypic attribute of erythroblasts proliferation. In this study, in vitro experiments showed that a newly synthesized chalcone (ZH-254) inhibited cell proliferation, caused apoptosis, arrested the cell cycle in the G1 phase, and downregulated Fli-1 expression by inhibiting Fli-1 promoter activity. In vivo experiments showed that ZH-254 could effectively alleviate splenomegaly and prolong the survival of erythroleukemia mice. RT-PCR and Western blot analysis showed that ZH-254 could regulate the expression of Fli-1 target genes and G1-phase-related cell cycle proteins, including Rb, Bcl-2, Bax, ERK1/2, Gata-1, P110, SHIP-1, p-ERK1, CDK4, C-myc, Cyclin D1, Smad-3, GSK-3, and p21. Among them, the compound most significantly regulated the expression and phosphorylation of ERK1, the target gene of Fli-1 involved in regulating cell proliferation and apoptosis. Thus, ZH-254 restricts the malignancy of erythroleukemia by causing the inactivation of Fli-1 expression via suppressing its promoter activity, further regulating the expression and phosphorylation of ERK1- and G1-phase-related genes. These results reveal the critical role of Fli-1 in the growth and survival of various hematological malignancies and point to chalcone derivatives as lead compounds for the development of anti-Fli-1 drugs for the treatment of erythroleukemia with overexpression of Fli-1.

Erythroleukemia: an Update

PURPOSE OF THE REVIEW

Acute erythroleukemia (AEL) is a rare form of acute myeloid leukemia recognized by erythroblastic proliferation. Many controversies remain around diagnosis influencing prognostic and therapeutic implications relating to this unique leukemia subset.

RECENT FINDINGS

The 2016 WHO classification includes more clear and restrictive diagnostic criteria for AEL. Primary acute erythroid leukemia is associated with complex and high-risk karyotypes including chromosomes 5q and 7q abnormalities. Mutational data shows that AEL is characterized by far lower NPM1 and FLT3-ITD mutation rates and higher mutational rates in TP53 compared with other AML subtypes. Hypomethylating agents have shown therapeutic value in AEL. In this article, we discuss the evolving diagnostic concepts of erythroleukemia, genomics, clinical outcome, and promising therapeutic targets through an appraisal of the current literature.

Erythroleukemia-historical perspectives and recent advances in diagnosis and management

Acute erythroleukemia is a rare form of acute myeloid leukemia recognized by its distinct phenotypic attribute of erythroblastic proliferation. After a century of its descriptive history, many diagnostic, prognostic, and therapeutic implications relating to this unique leukemia subset remain uncertain. The rarity of the disease and the simultaneous involvement of its associated myeloid compartment have complicated in vitro studies of human erythroleukemia cell lines. Although murine and cell line erythroleukemia models have provided valuable insights into pathophysiology, translation of these concepts into treatment are not forthcoming. Integration of knowledge gained through a careful study of these models with more recent data emerging from molecular characterization will help elucidate key mechanistic pathways and provide a much needed framework that accounts for erythroid lineage-specific attributes. In this article, we discuss the evolving diagnostic concept of erythroleukemia, translational aspects of its pathophysiology, and promising therapeutic targets through an appraisal of the current literature.