Myeloproliferative and lymphoproliferative malignancies occurring in the same patient: a nationwide discovery cohort.

Myeloid and lymphoid malignancies are postulated to have distinct pathogenetic mechanisms. The recent observation that patients with a myeloproliferative neoplasm have an increased risk of developing lymphoproliferative malignancy has challenged this assumption. We collected a nationwide cohort of patients with both malignancies.

Clonal hematopoiesis predicts development of therapy-related myeloid neoplasms post-autologous stem cell transplantation.

Therapy-related myeloid neoplasms (tMN) develop after exposure to cytotoxic and radiation therapy, and due to their adverse prognosis, it is of paramount interest to identify patients at high risk. The presence of clonal hematopoiesis has been shown to increase the risk of developing tMN. The value of analyzing hematopoietic stem cells harvested at leukapheresis before autologous stem cell transplantation (ASCT) with next-generation sequencing and immunophenotyping represents potentially informative parameters that have yet to be discovered.

A decade with whole exome sequencing in haematology.

The first decade of capture-based targeted whole exome sequencing (WES) has now passed, while the sequencing modality continues to find more widespread usage in clinical research laboratories and still offers an unprecedented diagnostic assay in terms of throughput, informational content and running costs. Until quite recently, WES has been out of reach for many clinicians and molecular biologists, and it still poses issues or is met with some reluctance with regards to cost versus benefit in terms of effective assay costs, hands-on laboratory work and data analysis bottlenecks. Although WES is used more than ever, it may also be argued that the usage is peaking and that new implementations, or relevance in its current state, will likely be leveling off during the following decade as the price on whole genome sequencing continues to drop.

The concept of leukaemic stem cells in acute myeloid leukaemia 25 years on: hitting a moving target.

The concept of leukaemic stem cells (LSCs) was experimentally suggested 25 years ago through seminal data from John Dick's group, who showed that a small fraction of cells from acute myeloid leukaemia (AML) patients were able to be adoptively transferred into immunodeficient mice. The initial estimation of the frequency was 1:250 000 leukaemic cells, clearly indicating the difficulties ahead in translating knowledge on LSCs to the clinical setting. However, the field has steadily grown in interest, expanse and importance, concomitantly with the realisation of the molecular background for AML culminating in the sequencing of hundreds of AML genomes.

Systematic evaluation of signal-to-noise ratio in variant detection from single cell genome multiple displacement amplification and exome sequencing.

Background: The current literature on single cell genomic analyses on the DNA level is conflicting regarding requirements for cell quality, amplification success rates, allelic dropouts and resolution, lacking a systematic comparison of multiple cell input down to the single cell. We hypothesized that such a correlation assay would provide an approach to address the latter issues, utilizing the leukemic cell line OCI-AML3 with a known set of genetic aberrations.

Results: By analyzing single and multiple cell replicates (2 to 50 cells) purified by micromanipulation and serial dilution we stringently assessed the signal-to-noise ratio (SNR) from single as well as a discrete number of cells based on a multiple displacement amplification method, with whole exome sequencing as signal readout.

Combination of RNA- and exome sequencing: Increasing specificity for identification of somatic point mutations and indels in acute leukaemia.

Handling of large data sets from whole exome sequencing is a challenge, not the least because of the high risk of detecting false positive variants. Furthermore, there is still no consensus regarding what stage filtering of variants is performed in the bioinformatics pipeline to produce consistent result sets, the extent of filtering and how this is most optimal performed. We hypothesized that combination of coding transcriptome and exomes enables precise identification of both somatic single nucleotide and indel variants early in the bioinformatics process, superseding the need for extensive annotation and validation from external databases.

Can exome scans be expected to be part of real-time decision-making in patients with haematological cancers?

The laboratory aspects of diagnosis of patients with haematological malignancies are forever changing. Microscopic examination of blood and bone marrow smears, cytogenetics, flow cytometry and single-assay molecular diagnostics have been and are still essential tools in cancer diagnostics. Flow cytometry has brought the unprecedented possibility of rapid multiplexing and characterization of complex immunophenotypic patterns.

Novel scripts for improved annotation and selection of variants from whole exome sequencing in cancer research.

Sequencing the exome is quickly becoming the preferred method for discovering disease-inducing mutations. While obtaining data sets is a straightforward procedure, the subsequent analysis and interpretation of the data is a limiting step for clinical applications. Thus, while the initial mutation and variant calling can be performed by a bioinformatician or trained researcher, the output from robust packages such as MuTect and GATK is not directly informative for the general life scientists.

Nature and nurture: a case of transcending haematological pre-malignancies in a pair of monozygotic twins adding possible clues on the pathogenesis of B-cell proliferations.

We describe a comprehensive molecular analysis of a pair of monozygotic twins, who came to our attention when one experienced amaurosis fugax and was diagnosed with JAK2+ polycythaemia vera. He (Twin A) was also found to have an asymptomatic B-cell chronic lymphocytic leukaemia (B-CLL). Although JAK2-, Twin B was subsequently shown to have a benign monoclonal B-cell lymphocytosis (MBL).

Diagnosing and following adult patients with acute myeloid leukaemia in the genomic age.

The diagnosis and follow-up process of adult patients with acute myeloid leukaemia (AML) is challenging to clinicians and laboratory staff alike. While several sets of recommendations have been published over the years, the development of high throughput screening and characterization for both genetic and epigenetic events have evolved with astonishing speed. Here we attempt to provide a practical guide to diagnose and follow adult AML patients with a focus on how to balance the wealth of information on the one hand, with the restriction put on these processes in terms of time, feasibility and economy when caring for these patients, on the other.

Sensitive ligand-based protein quantification using immuno-PCR: A critical review of single-probe and proximity ligation assays.

Quantitative PCR (qPCR) of reverse-transcribed mRNA has revolutionized gene expression analyses. qPCR analysis is based on the prevalent assumption that mRNA transcript numbers provide an adequate measure of specific biomarker expression. However, taking the complexity of protein turnover into account, there is a need to correlate qPCR-derived transcriptional patterns with protein translational patterns so as to not leave behind important pathobiological details.

Delineation of known and new transcript variants of the SETMAR (Metnase) gene and the expression profile in hematologic neoplasms.

SET domain and mariner transposase fusion gene (SETMAR), also known as Metnase, has previously been shown to suppress the formation of chromosomal translocation in mouse fibroblasts. Despite the fact that hematologic malignancies are often characterized by chromosomal rearrangements, no studies have hitherto investigated the expression pattern of the gene in these disorders. We hypothesized that a high expression of SETMAR protected the cells from chromosomal rearrangements; thus, we examined the mRNA expression of SETMAR transcript variants in hematologic patients.

Titanocene-Catalyzed Reduction of Lactones to Lactols.

A convenient method for the conversion of lactones to lactols is described. The hydrosilylation to lactols is carried out via air-stable titanocene difluoride or a titanocene diphenoxide precatalyst using inexpensive polymethylhydrosiloxane (PMHS) as the stoichiometric reductant. These procedures have been demonstrated with a variety of substrates and proceed in good to excellent yield.