Molecular methods in diagnosis and monitoring of haematological malignancies

Resistance mechanisms to drug therapy in breast cancer and other solid tumors: An opinion

Cancer is an important contributor to mortality worldwide. Breast cancer is the most common solid tumor in women. Despite numerous drug combinations and regimens, all patients with advanced breast cancer, similarly to other solid tumors, inevitably develop resistance to treatment. Identified mechanisms of resistance could be classified into intra- and extracellular mechanisms. Intracellular mechanisms include drug metabolism and efflux, target modulations and damage restoration. Extracellular mechanisms might be attributed to the crosstalk between tumor cells and environmental factors. However, current knowledge concerning resistance mechanisms cannot completely explain the phenomenon of multi-drug resistance, which occurs in the vast majority of patients treated with chemotherapy. In this opinion article, we investigate the role of these factors in the development of drug-resistance.

What do providers, payers and patients need from comparative effectiveness research on diagnostics? The case of HER2/Neu testing in breast cancer

AIMS

Comparing effectiveness of diagnostic tests is one of the highest priorities for comparative effectiveness research (CER) set by the Institute of Medicine. Our study aims to identify what information providers, payers and patients need from CER on diagnostics, and what challenges they encounter implementing comparative information on diagnostic alternatives in practice and policy.

MATERIALS & METHODS

Using qualitative research methods and the example of two alternative protocols for HER2 testing in breast cancer, we conducted interviews with 45 stakeholders: providers (n = 25) from four academic and eight nonacademic institutions, executives (n = 13) from five major US private payers and representatives (n = 7) from two breast cancer patient advocacies.

RESULTS

The need for additional scientific evidence to determine the preferred HER2 protocol was more common for advocates than payers (100 vs 54%; p = 0.0515) and significantly more common for advocates than providers (100 vs 40%; p = 0.0077). The availability of information allowing assessment of the implementation impact from alternative diagnostic protocols on provider institutions may mitigate the need for additional scientific evidence for some providers and payers (24 and 46%, respectively). The cost-effectiveness of alternative protocols from the societal perspective is important to payers and advocates (69 and 71%, respectively) but not to providers (0%; p = 0.0001 and p = 0.0001). The lack of reporting laboratory practices is a more common implementation challenge for payers and advocates (77 and 86%, respectively) than for providers (32%). The absence of any mechanism for patient involvement was recognized as a challenge by payers and advocates (69 and 100%, respectively) but not by providers (0%; p = 0.0001 and p = 0.0001).

CONCLUSION

Comparative implementation research is needed to inform the stakeholders considering diagnostic alternatives. Transparency of laboratory practices is an important factor in enabling implementation of CER on diagnostics in practice and policy. The incongruent views of providers versus patient advocates and payers on involving patients in diagnostic decisions is a concerning challenge to utilizing the results of CER.

Detection and clinical significance of gene rearrangements in Chinese patients with adult acute lymphoblastic leukemia

This study aimed to develop a novel multiplex reverse transcription-nested polymerase chain reaction (RT-nPCR) assay to accurately and effectively detect 10 common gene rearrangements in adult acute lymphoblastic leukemia (ALL) and to examine the clinicopathologic characteristics and other genetic aberrations of patients with ALL expressing different fusion genes. Our RT-nPCR assay had a positive detection rate of 35.15% (90/256) for the 10 fusion genes. BCR-ABL1, FUS-ERG, MLL-AF4, ETV6-RUNX1, E2A-PBX1, dupMLL, MLL-AF10, MLL-ENL, SET-NUP214 and SIL-TAL1 were detected in 36 (14.06%), 14 (5.47%), 14 (5.47%), four (1.56%), four (1.56%), five (1.95%), four (1.56%), two (0.78%), two (0.78%) and five patients (1.95%), respectively. The RT-nPCR results were further confirmed by split-out PCR, and cytogenetic and fluorescence in situ hybridization (FISH) analysis revealed corresponding translocations and fusions in 63 and 74 cases, respectively. JAK2 and IKZF1 mutations were commonly detected in patients with BCR-ABL1 ALL, and HOX overexpression was highly correlated with MLL fusions and SET-NUP214. This study demonstrates that RT-nPCR is an effective method for identifying 10 gene rearrangements in adult ALL, and it could potentially be developed for diagnostic use and prognostic studies of ALL.

On the Power of Additional and Complex Chromosomal Aberrations in CML

Unregulated proliferation of mainly myeloid bone marrow cells and genetic changes in the hematopoietic stem cell system are important features in Chronic Myeloid Leukemia (CML). In clinical diagnosis of CML, classical banding techniques, fluorescence in situ hybridization (FISH) probing for the Philadelphia chromosome (Ph) or polymerase chain reaction amplifying the fusion products of the BCR-ABL fusion are state of the art techniques. Nevertheless, the genome of CML patients harbors many more cytogenetic changes. These might be hidden in subpopulations due to clonal events or involved in extremely complex aberrations. To identify these additional changes, several cytogenetic and molecular genetic techniques could be applied. Nevertheless, it has been proposed that identifying these aberrations is time consuming and costly and since they cannot be converted into a benefit for the patients, the necessity to perform these investigations has been questioned. In the times where highly specialized medicine is advancing into several areas of cancer, this attitude needs to be reassessed. Therefore, we looked at the usefulness of a combination of different techniques to unravel the genetic changes in CML patients and to identify new chromosomal aberrations, which potentially can be correlated to different stages of the disease and the strength of therapy resistance. We are convinced that the combination of these techniques could be extremely useful in unraveling even the most complex karyotypes and in dissecting different clones contributing to the disease. We propose that by doing so, this would improve CML diagnostic and prognostic findings, especially with regard to CML resistance mechanisms and new therapeutic strategies.