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Selinexor, an oral Selective Inhibitor of Nuclear Export, targets Exportin 1 (XPO1, also termed CRM1). Non-clinical studies support combining selinexor with proteasome inhibitors (PIs) and corticosteroids to overcome resistance in relapsed/refractory multiple myeloma (RRMM). We conducted a phase I dose-escalation trial of twice-weekly selinexor in combination with carfilzomib and dexamethasone (SKd) to determine maximum tolerated dose in patients with RRMM (N = 21), with an expansion cohort to assess activity in carfilzomib-refractory disease and identify a recommended phase II dose (RP2D). During dose escalation, there was one dose-limiting toxicity (cardiac failure). The RP2D of twice-weekly SKd was selinexor 60 mg, carfilzomib 20/27 mg/m2 and dexamethasone 20 mg. The most common grade 3/4 treatment-emergent adverse events included thrombocytopenia (71%), anaemia (33%), lymphopenia (33%), neutropenia (33%) and infections (24%). Rates of ≥minimal response, ≥partial response and very good partial response were 71%, 48% and 14%, respectively; similar response outcomes were observed for dual-class refractory (PI and immunomodulatory drug)/quad-exposed (carfilzomib, bortezomib, lenalidomide and pomalidomide) patients (n = 17), and patients refractory to carfilzomib in last line of therapy (n = 13). Median progression-free survival was 3·7 months, and overall survival was 22·4 months in the overall population. SKd was tolerable and re-established disease control in RRMM patients, including carfilzomib-refractory patients. Registered at ClinicalTrials.gov (NCT02199665).

Telomerase reverse transcriptase is a catalytic subunit of the telomerase protein that is involved in the maintenance of genomic stability. TERT aberrations are important biomarkers in the diagnosis, prognosis, and treatment of many human cancers. The TERT promoter has proven to be a difficult region of testing amongst a variety of currently available technologies. TERT promoter mutation analysis was performed on brain tissue of a 62-year old male meningioma patient using MALDI-TOF (Agena Bioscience MassARRAY platform) and detected a low frequency TERT mutation. The pathologist questioned the result and sent some of the sample for additional testing to 2 different referral laboratories - one aliquot was sent for Pyrosequencing and the other for NGS - both with a higher limit of detection than MALDI-TOF. Neither methodology detected a TERT mutation. On the basis of these result the diagnosis was changed. Certain of our TERT mutation, an aliquot of the remaining extracted DNA was sent for digital droplet PCR (ddPCR) which has the same limit of detection as our MALDI-TOF platform. A TERT mutation was confirmed. This case highlights the challenges in TERT promoter mutation analysis as well as the significance of confirmatory testing. The importance of confirming results using platforms with an appropriate limit of detection is paramount in reducing under-reporting of low level mutations of clinical significance. [ABSTRACT FROM AUTHOR]

Anti-epidermal growth factor receptor-targeted therapy is only indicated in RAS wild-type colorectal carcinomas (CRCs). It is recommended that both NRAS and KRAS mutation testing to be performed before a CRC is considered RAS wild-type. Given that mutation-specific immunohistochemistry (IHC) has been shown to be sensitive and specific for the detection of NRAS mutations in melanoma, we assessed the specificity of NRAS mutation-specific IHC in CRC. IHC was performed on tissue microarrays containing 2823 consecutive CRC undergoing surgery with curative intent using a novel mutation-specific antibody to the protein produced by the NRAS mutation (clone SP174). Tissue microarrays were assessed by 2 observers and all IHC-positive or equivocal cases were repeated on whole sections to confirm the result. Positive cases then underwent molecular testing by matrix-assisted laser desorption/ionization-time of flight polymerase chain reaction. In total, 22 of 2823 (0.8%) CRCs demonstrated confirmed positive staining with complete interobserver concordance. RAS mutations were confirmed in all IHC-positive CRCs. In total, 11 cases harbored the NRASQ61R mutation. Surprisingly, 11 cases demonstrated the KRASQ61R mutation. We conclude that mutation-specific IHC with this currently available NRASQ61R antibody is highly specific for the presence of either NRASQ61R or KRASQ61R mutations in CRC. We caution that we did not assess the sensitivity of IHC and that this antibody does not detect other RAS mutations. Therefore, negative staining does not exclude a clinically significant RAS mutation. However, positive staining confirms the presence of an NRASQ61R or KRASQ61R mutation without the need for further molecular testing.

Genetic changes, in particular chromosomal aberrations, are a hallmark of acute lymphoblastic lymphoma (ALL) and accurate detection of them is important in ensuring assignment to the appropriate drug protocol. Our ability to detect these genetic changes has been somewhat limited in the past due to the necessity to analyse mitotically active cells by conventional G-banded metaphase analysis and by mutational analysis of individual genes. Advances in technology include high resolution, microarray-based techniques that permit examination of the whole genome. Here we will review the current available methodology and discuss how the technology is being integrated into the diagnostic setting.

The protocol reported in this chapter describes a method for the detection and spatial localisation of microRNAs (miRNAs) in cryopreserved primary leukaemic suspension cells using digoxigenin (DIG)-labelled, Locked Nucleic Acid (LNA)-modified probes, and fluorescence in situ hybridisation (FISH). The LNA probe hybridisation yields highly accurate signals able to discriminate between single nucleotide differences and hence between closely related miRNA family members. DIG-labelled LNA probes for mature miRNAs are detected using an anti-DIG fluorescein isothiocyanate (FITC) conjugated antibody and the fluorescent signals visualised with a confocal microscope, which permits the spatial localisation of the miRNAs. Using LNA-FISH, we visualised the spatial localisation of two mature miRNAs, miR-127 and miR-154, in primary acute myeloid leukaemia (AML) suspension cells, and thus, we confirmed their expression in a specific leukaemic subtype as measured by real-time PCR.