Faculty Bibliography

Using advances in genetic analysis to segment and direct treatment of multiple myeloma (MM) represents a way of maintaining therapeutic progress. Recent genetic analyses have opened the possibility of enhancing risk stratification approaches and of using different risk and biologic strata as part of clinical trials. The Myeloma Genome Project is a collaborative project that has compiled the largest set of cases with sequencing and have outcome data that are available for stratification purposes. Mutation-targeted treatment of the Ras pathway has been shown to be active in MM, but is compromised by the presence of the subclonal genetic variation typical of myeloma. Going forward, risk and biologically stratified therapy for MM looks to be a promising way of maintaining therapeutic progress, as does precision immunotherapy directed by the cellular context of the bone marrow.

BACKGROUND:Immunomodulatory derivatives (IMiDs), along with proteasome inhibitors, are key components of treatment regimens for multiple myeloma. Nonetheless, outcomes vary among treated individuals. Drug-specific gene-expression profile (GEP) signatures that aid the prediction of favourable and unfavourable outcomes can provide patients with the most effective therapy for their individual disease. We aimed to develop and validate a gene expression signature to suggest which patients would benefit most from IMiD-based therapies. METHODS:For this exploratory retrospective study, we selected a cohort of patients with newly diagnosed or relapsed or refractory multiple myeloma who were treated in clinical trials with IMiD-containing regimens. Cohorts were eligible if they had publicly available GEP data from patients' bone marrow plasma cells, with long-term follow-up and clinicopathological data. In the development stage of the model, we identified 176 IMiD response genes that were differentially expressed before and after IMiD exposure using pharmacogenomic GEP data from patients who had bone marrow samples taken before and 48 h after a test dose exposure with thalidomide (n=42), lenalidomide (n=18), or pomalidomide (n=18). 14 of these genes had p values less than 0·05 for associations with progression-free survival in patients who received thalidomide in induction and maintenance therapy in the Total Therapy (TT) 2 trial (ie, the training cohort). We combined the 14 genes to create a continuous IMiD-14 score and an optimal cutoff. The subgroup with an IMiD-14 score higher than the cutoff was deemed to be IMiD-resistant. We obtained validation cohorts from four studies of IMiD combination regimens: the TT3a trial (thalidomide in induction and maintenance), the TT3b trial (thalidomide in induction and lenalidomide in maintenance), the TT6 trial (thalidomide in induction and lenalidomide in maintenance), and the vincristine, doxorubicin, and dexamethasone (VAD) group of the HOVON65/GMMG-HD4 trial (thalidomide in maintenance). The primary endpoint was to show the prognostic value of the IMiD-14 gene signature for progression-free survival. FINDINGS/RESULTS:In the training cohort, progression-free survival was significantly shorter in the 83 patients with IMiD-14 high scores than in the 92 patients with IMiD-14 low scores; 3 year progression-free survival was 52% (95% CI 42-64) for the IMiD-14 high group versus 85% (78-92) for the IMiD-14 low group, with a hazard ratio (HR) of 2·51 (95% CI 1·72-3·66; p<0·0001). These findings were supported by the results in the validation cohorts, TT3a (115 patients with IMiD-14 high vs 160 patients with IMiD-14 low; 3 year progression-free survival 63% [95% CI 55-73] vs 87% [82-92]; HR 1·54 [1·11-2·15], p=0·010), TT3b (77 patients with IMiD-14 high vs 89 patients with IMiD-14 low; 62% [52-74] vs 80% [72-89]; HR 2·07 [1·28-3·34], p=0·0024), TT6 (20 patients with IMiD-14 high vs 36 patients with IMiD-14 low; 39% [22-68] vs 74% [61-90]; HR 2·40 [1·09-5·30], p=0·026), and the VAD group of HOVON65/GMMG-HD4 (65 patients with IMiD-14 high vs 77 patients with IMiD-14 low; 16% [9-28] vs 54% [44-67]; HR 2·29 [1·52-3·45], p<0·0001). INTERPRETATION/CONCLUSIONS:Our results suggest that the IMiD-14 model has prognostic value in patients with multiple myeloma who are treated with IMiDs. Some genes in the model could provide novel targets for IMiD resistance and therapeutic intervention. The IMiD-14 model warrants evaluation in prospective studies. FUNDING/BACKGROUND:Conquer Cancer Foundation ASCO Young Investigator Award and the Carolinas Myeloma Research Fund.

Multiple myeloma (MM) is a malignancy of plasma cells. Genome-wide association studies have shown that variation at 5q15 influences MM risk. Here, we have sought to decipher the causal variant at 5q15 and the mechanism by which it influences tumorigenesis. We show that rs6877329 G > C resides in a predicted enhancer element that physically interacts with the transcription start site of ELL2. The rs6877329-C risk allele is associated with reduced enhancer activity and lowered ELL2 expression. Since ELL2 is critical to the B cell differentiation process, reduced ELL2 expression is consistent with inherited genetic variation contributing to arrest of plasma cell development, facilitating MM clonal expansion. These data provide evidence for a biological mechanism underlying a hereditary risk of MM at 5q15.

Aims We sought to evaluate the first-in-man use of a new system for implantation of covered stents in patients with complex structural and CHD. Methods and results Retrospective data were collected of the first 13 NuDELâ„¢ delivery systems used in patients. The NuDELâ„¢ comprises a covered Cheatham-Platinum stent mounted on a balloon-in-balloon and pre-loaded in a long delivery sheath. Data were collected from three centres in the United Kingdom and Ireland. A total of 13 covered stents were delivered via 12 NuDELâ„¢ delivery systems in 12 patients. Among them, six patients had coarctation of the aorta, five patients had right ventricular outflow tract stenosis, and one patient had severe stenosis of a Mustard systemic venous baffle. There were no complications, and all the stents were deployed in the desired position with satisfactory haemodynamic results.

The outcomes for the majority of patients with myeloma have improved over recent decades, driven by treatment advances. However, there is a subset of patients considered to have high-risk disease who have not benefited. Understanding how high-risk disease evolves from more therapeutically tractable stages is crucial if we are to improve outcomes. This can be accomplished by identifying the genetic mechanisms and mutations driving the transition of a normal plasma cell to one with the features of the following disease stages: monoclonal gammopathy of undetermined significance, smouldering myeloma, myeloma and plasma cell leukaemia. Although myeloma initiating events are clonal, subsequent driver lesions often occur in a subclone of cells, facilitating progression by Darwinian selection processes. Understanding the co-evolution of the clones within their microenvironment will be crucial for therapeutically manipulating the process. The end stage of progression is the generation of a state associated with treatment resistance, increased proliferation, evasion of apoptosis and an ability to grow independently of the bone marrow microenvironment. In this Review, we discuss these end-stage high-risk disease states and how new information is improving our understanding of their evolutionary trajectories, how they may be diagnosed and the biological behaviour that must be addressed if they are to be treated effectively.

The genetic basis underlying the inherited risk of developing multiple myeloma (MM) is largely unknown. To examine the impact of rare protein altering variants on the risk of developing MM we analyzed high-coverage exome sequencing data on 513 MM cases and 1,569 healthy controls, performing both single variant and gene burden tests. We did not identify any recurrent coding low-frequency alleles (1-5%) with moderate effect that were statistically associated with MM. In a gene burden analysis we did however identify a promising relationship between variation in the marrow kinetochore microtubule stromal gene KIF18A, which plays a role in control mitotic chromosome positioning dynamics, and risk of MM (P =3.6x10-6). Further analysis showed KIF18A displays a distinct pattern of expression across molecular subgroups of MM as well as being associated with patient survival. Our results inform future study design and provide a resource for contextualizing the impact of candidate MM susceptibility genes.

INTRODUCTION/BACKGROUND:Creation of a fenestration during completion of a total cavopulmonary connection (TCPC) has been associated with a reduction in early mortality and morbidity. However, the long-term benefits are negated by an associated limitation in exercise tolerance and the potential risks of thrombo-embolic complications. We sought to describe the safety and efficacy of an Amplatzer Duct Occluder II (ADO II) for transcatheter fenestration closure following TCPC. MATERIAL AND METHODS/METHODS:Between January 2000 and July 2014, 102 patients underwent percutaneous closure of extra-cardiac TCPC fenestrations with a range of devices. Patients in whom fenestration closure was performed with an ADO II and who had at least 6 months of follow-up were included in this study. RESULTS:< 0.001). Eight patients developed heart failure symptoms, managed by optimization of medical therapy, with 1 patient requiring device removal to reopen the fenestration. Color Doppler transthoracic echocardiography demonstrated residual flow across the device in 18 (38%), 10 (22%), 5 (11%) and 4 (9%) patients before discharge, at 1 and 6 months, and at the latest outpatient visit, respectively. CONCLUSIONS:The ADO II can be safely and effectively used to close fenestrations in extra-cardiac type Fontan completions. Many of the design features of this device confer potential benefit in this population.

Osteolytic bone lesions are a hallmark of multiple myeloma (MM) bone disease. Bone destruction is associated with severely imbalanced bone remodeling, secondary to increased osteoclastogenesis and significant osteoblast suppression. Lytic lesions of the pelvis are relatively common in MM patients and are known to contribute to the increased morbidity because of the high risk of fracture, which frequently demands extensive surgical intervention. After observing unexpected radiological improvement in serial large pelvic CT assessment in a patient treated in a total therapy protocol, the radiographic changes of pelvic osteolytic lesions by PET/CT scanning in patients who received Total Therapy 4 (TT4) treatment for myeloma were retrospectively analyzed. Sixty-two (62) patients with lytic pelvic lesions >1 cm in diameter were identified at baseline PET/CT scanning. Follow-up CT studies showed that 27 of 62 patients (43%) with large baseline pelvic lesions achieved significant reaccumulation of radiodense mineralization at the lytic cortical site. The average size of lytic lesions in which remineralization occurred was 4 cm (range, 1.3 to 10 cm). This study clearly demonstrates that mineral deposition in large pelvic lesions occurs in a significant proportion of MM patients treated with TT4, potentially affecting patient outcomes, quality of life, and future treatment strategies. © 2017 American Society for Bone and Mineral Research.

We examined a set of 805 cases that underwent DNA sequencing using the FoundationOne Heme (F1H) targeted sequencing panel and gene expression profiling. Known and likely variant calls from the mutational data were analyzed for significant associations with gene expression defined translocation cyclin D (TC) molecular subgroups. The spectrum of KRAS, NRAS, and BRAF codon mutations varied across subgroups with NRAS mutations at Q61 codon being common in hyperdiploid (HRD) and t(11;14) myeloma while being rare in MMSET and MAF. In addition, the presence of RAS-RAF mutations was inversely associated with NFκB pathway activation in all subgroups excluding MAF. In the MMSET subgroup, cases with low FGFR3 expression frequently had RAS-RAF mutations. Conditional inference tree analysis determined that mutation and homozygous deletion of TP53, CDKN2C, and RB1 were key prognostic factors associated with adverse outcome in a non-relapse clinical setting. In conclusion, this study highlights the heterogeneity in the distribution and clinical outcomes of RAS codon and other mutations in multiple myeloma dependent upon primary molecular subgroup.