Consensus JH gene probes with conjugated 3'-minor groove binder for monitoring minimal residual disease in acute lymphoblastic leukemia.

Several approaches for the detection of minimal residual disease (MRD) in childhood acute lymphoblastic leukemia (ALL) have shown the importance of determining the level of MRD precisely. In the present study, we tested a new real-time quantitative polymerase chain reaction (RQ-PCR) strategy with minor groove binder (MGB) technology for immunoglobulin heavy chain gene rearrangements by positioning a MGB probe at the germline JH segments and one of the primers at the downstream introns in combination with an allele-specific oligonucleotide (ASO) primer complementary to the VH-DH or DH-JH junctional region. A MGB probe forms extremely stable duplexes with single-stranded DNA targets, allowing the use of shorter probes for hybridization-based assays.

Short consensus probes with 3'-minor groove binder of the immunoglobulin heavy-chain gene for real-time quantitative PCR in B-cell non-Hodgkin lymphomas.

We used 3'-minor groove binder (MGB) technology to develop consensus fluorogenically labeled probes of the immunoglobulin heavy-chain (IgH) gene for detecting minimal residual disease (MRD) in B-cell non-Hodgkin lymphoma (B-NHL). Sequence data from 59 patients with B-NHLs revealed a narrow consensus region as a result of somatic hypermutations and variable VH usage, indicating that it would be difficult to design ordinary non-MGB probes. MGB probes, characterized by shorter length but higher melting temperature, are more suitable for this situation than ordinary non-MGB probes.

Development of consensus fluorogenically labeled probes of the immunoglobulin heavy-chain gene for detecting minimal residual disease in B-cell non-Hodgkin lymphomas.

We have examined 72 patients with B-cell non-Hodgkin lymphoma (B-NHL) in order to search for consensus sequences of the immunoglobulin heavy chain (IgH) gene, and developed consensus fluorogenically labeled probes for use in an allele-specific oligonucleotide (ASO) real-time quantitative polymerase chain reaction (RQ-PCR) assay of minimal residual disease (MRD). We detected a clonal IgH variable region (VH) sequence in 51 (70.8%) of the 72 B-NHLs, the most frequent VH gene usages being VH3 and VH4 (45/51, 88.

Quantitative assessment of contaminating tumor cells in autologous peripheral blood stem cells of B-cell non-Hodgkin lymphomas using immunoglobulin heavy chain gene allele-specific oligonucleotide real-time quantitative-polymerase chain reaction.

A real-time quantitative-polymerase chain reaction (RQ-PCR) targeting the immunoglobulin heavy chain (IgH) gene has been used for the quantification of minimal residual disease (MRD) in B-cell hematological malignancies. In non-Hodgkin lymphoma (NHL), experimental costs are increased, as a large number of primer-probe sets are required because of diversity, due to somatic and ongoing mutations of the IgH gene. We developed an allele-specific oligonucleotide (ASO) combined with a germline consensus probe-based RQ-PCR assay and examined MRD in peripheral blood stem cells (PBSC).

Quantitative assessment of minimal residual disease in childhood lymphoid malignancies using an allele-specific oligonucleotide real-time quantitative polymerase chain reaction.

We developed an assay using a real-time quantitative polymerase chain reaction (RQ-PCR) for the quantitative assessment of minimal residual disease (MRD) in childhood lymphoid malignancies by using a consensus V-region probe combining a allele-specific oligonucleotide (ASO) reverse primer. Our strategy employs a set consisting of a consensus V-region probe, an ASO reverse primer, and a patient-specific forward primer for clonal antigen-receptor (IgH, immunoglobulin heavy chain; TCR, T-cell receptor) gene rearrangements (IgH-ASO and TCR-ASO RQ-PCR assays). The limit of detection in both assays was 5 copies of the target/10(5) cell equivalents.

Esophageal extraskeletal Ewing's sarcoma.

Extraskeletal Ewing's sarcoma is a rare tumor. The most common sites of occurrence are on the trunk, extremities, and retroperitoneum. This type of tumor is well characterized by recurrent chromosomal translocation such as t (11;22) (q24;q12) (EWSR1/FLI1) or t (21;22) (q22;q12) (EWSR1/ERG) and overexpression of MIC2/CD99 on tumor cell membrane.