Frequency of chromosomal abnormalities in Pakistani adults with acute lymphoblastic leukemia

Digital gene expression profiling analysis of childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is the most commonly diagnosed malignancy in children. It is a heterogeneous disease, and is determined by multiple gene alterations and chromosomal rearrangements. To improve current understanding of the underlying molecular mechanisms of ALL, the present study profiled genome‑wide digital gene expression (DGE) in a population of children with ALL in China. Using second‑generation sequencing technology, the profiling revealed that 2,825 genes were upregulated and 1,952 were downregulated in the ALL group. Based on the DGE profiling data, the present study further investigated seven genes (WT1, RPS26, MSX1, CD70, HOXC4, HOXA5 and HOXC6) using reverse transcription‑quantitative polymerase chain reaction analysis. Gene Ontology analysis suggested that the differentially expressed genes were predominantly involved in immune cell differentiation, metabolic processes and programmed cell death. The results of the present study provided novel insights into the gene expression patterns in children with ALL.

Multiplex RT-PCR Assay for Detection of Common Fusion Transcripts in Acute Lymphoblastic Leukemia and Chronic Myeloid Leukemia Cases

BACKGROUND

Acute lymphoblastic leukemia (ALL) is a heterogeneous disease which requires a risk-stratified approach for appropriate treatment. Specific chromosomal translocations within leukemic blasts are important prognostic factors that allow identification of relevant subgroups. In this study, we developed a multiplex RT-PCR assay for detection of the 4 most frequent translocations in ALL (BCR-ABL, TEL-AML1, MLL-AF4, and E2A- PBX1).

MATERIALS AND METHODS

A total of 214 diagnosed ALL samples from both adult and pediatric ALL and 14 cases of CML patients (154 bone marrow and 74 peripheral blood samples) were assessed for specific chromosomal translocations by cytogenetic and multiplex RT-PCR assays.

RESULTS

The results showed that 46 cases of ALL and CML (20.2%) contained the fusion transcripts. Within the positive ALL patients, the most prevalent cryptic translocation observed was mBCR-ABL (p190) at 8.41%. In addition, other genetic rearrangements detected by the multiplex PCR were 4.21% TEL-AML1 and 2.34% E2A-PBX1, whereas MLL-AF4 exhibited negative results in all tested samples. Moreover, MBCR-ABL was detected in all 14 CML samples. In 16 samples of normal karyotype ALL (n=9), ALL with no cytogentic result (n=4) and CML with no Philadelphia chromosome (n=3), fusion transcripts were detected.

CONCLUSIONS

Multiplex RT-PCR provides a rapid, simple and highly sensitive method to detect fusion transcripts for prognostic and risk stratification of ALL and CML patients.