PAX5 deletion is common and concurrently occurs with CDKN2A deletion in B-lineage acute lymphoblastic leukemia.

The PAX5 is essential in normal B-cell lymphopoiesis and deregulation of PAX5 function is believed to contribute to leukemogenesis in B-ALL. We performed a comprehensive study using FISH, G-banding and IHC to identify PAX5 deletion and expression in 102 CD19+ clinical B-ALL cases (79 children and 33 adults) and investigated its relationship with common cytogenetic changes including BCR-ABL1, ETV6-RUNX1 and MLL rearrangements, and CDKN2A deletion. The incidences of translocations and deletions were 2.

Increased copy number of the interleukin-6 receptor gene is associated with adverse survival in multiple myeloma patients treated with autologous stem cell transplantation.

Interleukin-6 (IL-6) is a potent pleiotropic cytokine that regulates plasma cell (PC) growth via the IL-6 receptor (IL-6R). We hypothesized that up-regulation of IL-6R in myeloma cells might confer the growth privilege to myeloma cells over bone marrow (BM) hematopoietic cells. We investigated the frequency and prognostic implication of increased copy number of the IL-6R gene by fluorescence in situ hybridization (FISH) in patients with newly diagnosed multiple myeloma (MM).

Homozygous deletion of CDKN2A (p16, p14) and CDKN2B (p15) genes is a poor prognostic factor in adult but not in childhood B-lineage acute lymphoblastic leukemia: a comparative deletion and hypermethylation study.

The biological behavior of childhood B-lineage acute lymphoblastic leukemia (B-ALL) is different from that of adults. We performed a comprehensive analysis of the deletion and the methylation profile of CDKN2A (hereafter identified separately as p16 and p14, for the different proteins encoded) and CDKN2B (hereafter p15) in 91 newly diagnosed B-ALL patients (61 children, 30 adults). The prognostic significance of the profiles of these genes and the association between alterations in these genes and known cytogenetic prognostic factors (BCR/ABL; ETV6/RUNX1, formerly TEL/AML1; MLL rearrangement; and ploidy changes of chromosomes) were also assessed.

p15INK4b methylation correlates with thrombocytopenia, blast percentage, and survival in myelodysplastic syndromes in a dose dependent manner: quantitation using pyrosequencing study.

We investigated how the quantity of p15INK4b methylation related to International Prognosic Scoring System variables and survival in 74 patients with de novo myelodysplastic syndrome (MDS). Pyrosequencing of 11 consecutive CpG sites of the p15INK4b promotor region was performed, with the extent of CpG cytosine methylation assessed in terms of methylation level (MtL). Patients with >5% bone marrow blasts had higher MtL than patients with <5% blasts (10.

A study on the incidence of ABL gene deletion on derivative chromosome 9 in chronic myelogenous leukemia by interphase fluorescence in situ hybridization and its association with disease progression.

Fluorescence in situ hybridization for the BCR/ABL rearrangement in 138 bone marrow specimens from 59 Philadelphia(+) (Ph(+)) chronic myelogenous leukemia (CML) patients, 35 Ph(+) acute lymphoblastic leukemia (ALL) patients, and 57 Ph(-) ALL patients was used. Sixteen (27.1%) of the 59 CML patients had deletions of the residual ABL gene on the derivative chromosome 9.

RARA fluorescence in situ hybridization overcomes the drawback of PML/RARA fluorescence in situ hybridization in follow-up of acute promyelocytic leukemia.

Determination of the remission of acute promyelocytic leukemia (APL) after chemotherapy can be difficult because many cases of APL show reverse transcription polymerase chain reaction positivity after consolidation treatment. Moreover, the discrimination of leukemic promyelocytes and regenerating promyelocytes by morphology is sometimes difficult. Although PML/RARA fluorescence in situ hybridization (FISH) can help, the major drawback of FISH is its high false positive rate, which reaches up to 5-10%.