Acute non-lymphocytic leukemia with t(16;21)

Unmanipulated haploidentical peripheral blood stem cell transplantation for patients with Philadelphia-negative acute lymphoblastic leukaemia in first complete remission

Haploidentical peripheral blood stem cell transplantation (Haplo-PBSCT) is a promising treatment option for patients with Ph-negative acute lymphoblastic leukemia (ALL). In this study, we retrospectively analyzed data from Ph-negative ALL patients who underwent haplo-PBSCT during their first complete remission (CR1), and compared the long-term outcomes between the standard-risk and high-risk patients. The 3-year probability of relapse was 7.6% and 16.7% for the standard- and high-risk group (p = .274). The 3-year probability of disease-free survival (DFS) and overall survival (OS) for the standard-risk versus high-risk groups were 84.6% versus 50% (p = .0063) and 92.3% versus 61.1% (p = .046), respectively. Univariate analysis showed that a diagnosis of high risk with fusion/mutation genes were associated with worse outcomes, which was confirmed by multivariate analysis (p = .016). In summary, haplo-PBSCT may be a promising alternative for patients with Ph-negative ALL in CR1, although the fusion/mutation genes in high-risk patients may relatively impair the long-term efficacy compared with standard-risk patients.

Clinical characteristics and laboratory analyses of acute myeloid leukemia with t(16;21)(p11;q22)

The present study reviewed three patients with acute myeloid leukemia (AML) who had the specific genetic abnormality t(16;21)(p11;q22). To investigate the clinical and laboratory characteristics of AML with t(16;21)(p11;q22) translocation, the similarities and differences of clinical characteristics and laboratory examinations were compared, and a literature review was conducted. According to the French-American-British classification system, patient 1 was M4, patient 2 was M1 and patient 3 was M2. The cytogenetic aberrations were 46, XY, t(16;21)(p11;q22)/47, idem, +21 for patient 1 and 46, XX, t(16;21)(p11;q22) for patients 2 and 3. Cytophagocytosis and cluster of differentiation 56 antigen expression were found in all three cases. The prognosis was poor in all the cases. AML with t(16;21)(p11;q22) is a specific subtype of AML that exhibits unique characteristics of morphology, immunology, cytogenetics and clinical features, as well as a poor prognosis. Stem cell transplantation may be the first and only choice for treatment.

Establishment and characterization of a novel acute myeloid leukemia cell line, JIH-4, carrying a t(16;21)(p11.2;q22) and expressing the FUS-ERG fusion

Human leukemia cell lines are powerful tools in the study of leukemogenesis, particularly for rare but recurrent subtypes such as acute myeloid leukemia (AML) with the t(16;21)(p11.2;q22) and FUS-ERG fusion. Four AML cell lines carrying a t(16;21)(p11.2;q22) have been described previously. We report a novel AML cell line, designated JIH-4, for which karyotypic analysis demonstrated a single abnormality, t(16;21)(p11.2;q22). The FUS-ERG fusion transcript was identified by reverse transcriptase polymerase chain reaction (RT-PCR). Neither Epstein-Barr virus nor mycoplasma was detected in JIH-4 cells. The morphology and immunoprofile of JIH-4 cells display typical features of myelogenous lineage, and short tandem-repeat PCR comparison with the donor patient's bone marrow cells confirm the cell line's authenticity. Tumor masses were found in 50% of inoculated mice 83 days after subcutaneous injection with JIH-4 cells. Our results confirm that JIH-4 cells are derived from the donor patient's leukemia cells and support using the JIH-4 cell line as a valuable tool in the study of leukemogenesis.

Novel chromosome 16 abnormality--der(16)del(16) (q13)t(16;21)(p11.2;q22)--associated with acute myeloid leukemia

Inversion of chromosome 16 is a common feature of acute myeloid leukemia (AML) M4, while t(16;21), although also associated with AML, appears to be a separate entity. We present a patient with myelodysplastic syndrome (MDS) who transformed to AML-M1. The karyotype was normal at diagnosis; at 15 months, hematological evidence of transformation was present, and repeat cytogenetics showed a novel rearrangement of one chromosome 16. Two breaks had occurred; one in the short arm at 16p11, with translocation of the segment distal to this onto chromosome 21q, and the other in the long arm at 16q22 with subsequent deletion of the segment from 16q22-->qter. Fluorescence in situ hybridization (FISH) confirmed the abnormalities detected by cytogenetics and excluded involvement of the AML1 gene on 21q22. While the 16q22 breakpoint was at the usual site for the inv(16), the 16p11 was not. The patient is more characteristic of t(16;21) than inv(16), and adds to the spectrum of chromosome 16 abnormalities in AML.

Myeloid differentiation antigen and cytokine receptor expression on acute myelocytic leukaemia cells with t(16;21)(p11;q22): frequent expression of CD56 and interleukin-2 receptor alpha chain

We report the cellular characteristics of cells from three patients with de novo acute myelocytic leukaemia (AML) with t(16;21)(p11;q22), two M4 and one M5a according to the FAB classification, and two permanent cell lines with t(16;21)(p11;q22), TSU1621MT and YNH-1. The FUS/ERG fusion mRNA was demonstrated in all cases by reverse transcriptase-polymerase chain reaction (RT-PCR). The immunophenotypes of the AML cells, and YNH-1 and TSU1621MT cell lines with t(16;21) were characterized as CD34+CD33+CD13+CD11b+CD18+CD56+ HLA-DR-/+. Cells from all samples strongly expressed c-kit, granulocyte colony-stimulating factor receptor (G-CSFR), c-fms (macrophage colony-stimulating factor receptor), interleukin-3 receptor alpha chain (IL-3Ralpha), and granulocyte macrophage colony-stimulating factor receptor alpha chain (GM-CSFRalpha), and these data corresponded well to the growth responsiveness to the cytokines. IL-2Ralpha expression was also found in all t(16;21) samples, but IL-2 did not act on the proliferation of the leukaemic cells in in vitro cultures. G-CSF distinctly promoted the proliferation of leukaemic cells of t(16;21) AML, but did not enhance the expression of MPO and neutrophil differentiation of these cells. Our findings indicate that AML cells with t(16;21) preserve stem cell properties such as CD34 and c-kit expression, and suggest that they have the potential to differentiate into a monocytic lineage. The relationship between the unique cellular characteristics (especially CD56 and IL-2Ralpha expression) and FUS/ERG protein remains undetermined.

Establishment and characterization of IRTA17 and IRTA21, two novel acute non-lymphocytic leukaemia cell lines with t(16;21) translocation

The t(16;21)(p11;q22) translocation is an infrequent chromosomal abnormality, but seems specific to acute non-lymphocytic leukaemia (ANLL). We established two cell lines with t(16;21)(p11;q22) from the bone marrow of a patient with ANL in relapse. Their morphological, karyotypic, immunohistochemical and genetic features are examined. Although both cell lines show monocytoid features morphologically, they express only CD13 (My7) and CD34, and neither expressed monocytoid or lymphoid markers. Reverse transcription-polymerase chain reaction showed that both cell lines expressed a similar TLS-ERG chimaeric mRNA as a result of the t(16;21)(p11;q22) translocation. As far as we know, there is no report of a leukaemia cell line with t(16;21). These cell lines represent a useful tool for leukaemia research.