Constitutional mutation in CDKN2A is associated with long term survivorship in multiple myeloma: a case report.

BACKGROUND: Multiple Myeloma is a cancer of plasma cells associated with significantly reduced survival. Long term survivorship from myeloma is very rare and despite advances in its treatment the disease is generally considered incurable. We report a patient diagnosed with myeloma carrying a germline mutation of a tumour suppressor gene who has effectively been cured. CASE PRESENTATION: A 36-year-old woman was diagnosed with IgG lambda myeloma in 1985. She was treated with melphalan chemotherapy followed by high-dose melphalan and autologous stem cell rescue and since remained in complete remission despite not having received any additional therapy. After eliciting a prior history of multiple primary melanomas and breast cancer, she was tested for and shown to be a carrier for a germline mutation in CDKN2A. CONCLUSIONS: This is the second case report of germline mutation of CDKN2A being associated with myeloma. CDKN2A is a stabiliser of p53. Long term survivorship after high dose DNA damaging chemotherapy with melphalan in this patient is compatible with an increased chemo-sensitivity due to impairment of the DNA repair pathway.

Osteonecrosis of the jaw and renal safety in patients with newly diagnosed multiple myeloma: Medical Research Council Myeloma IX Study results.

Bisphosphonates are recommended in patients with osteolytic lesions secondary to multiple myeloma. We report on the safety of bisphosphonate therapy with long-term follow-up in the Medical Research Council Myeloma IX study. Patients with newly diagnosed multiple myeloma were randomised to zoledronic acid (ZOL; 4 mg intravenously every 21-28 d) or clodronate (CLO; 1600 mg/d orally) plus chemotherapy. Among 1960 patients (5.9-year median follow-up), both bisphosphonates were well tolerated. Acute renal failure events were similar between groups (ZOL 5.2% vs. CLO 5.8% at 2 years; incidence plateaued thereafter). The overall incidence of confirmed osteonecrosis of the jaw (ONJ) was low, but higher with ZOL (ZOL 3.7% vs. CLO 0.5%; P < 0.0001). ONJ events were generally low grade and most occurred between 8 and 30 months (median time to ONJ, 23.7 months). Among 10 patients with ONJ recovery data, four patients in the ZOL group completely recovered, two patients improved, and three patients experienced no improvement; one CLO patient experienced no improvement. Dental surgery or trauma preceded ONJ in six ZOL patients. The incidence of renal adverse events was similar for ZOL and CLO. ONJ incidence remained low and was lower with CLO compared to ZOL. We have seen no further ONJ cases to date.

Aberrant global methylation patterns affect the molecular pathogenesis and prognosis of multiple myeloma.

We used genome-wide methylation microarrays to analyze differences in CpG methylation patterns in cells relevant to the pathogenesis of myeloma plasma cells (B cells, normal plasma cells, monoclonal gammopathy of undetermined significance [MGUS], presentation myeloma, and plasma cell leukemia). We show that methylation patterns in these cell types are capable of distinguishing nonmalignant from malignant cells and the main reason for this difference is hypomethylation of the genome at the transition from MGUS to presentation myeloma. In addition, gene-specific hypermethylation was evident at the myeloma stage. Differential methylation was also evident at the transition from myeloma to plasma cell leukemia with remethylation of the genome, particularly of genes involved in cell-cell signaling and cell adhesion, which may contribute to independence from the bone marrow microenvironment. There was a high degree of methylation variability within presentation myeloma samples, which was associated with cytogenetic differences between samples. More specifically, we found methylation subgroups were defined by translocations and hyperdiploidy, with t(4;14) myeloma having the greatest impact on DNA methylation. Two groups of hyperdiploid samples were identified, on the basis of unsupervised clustering, which had an impact on overall survival. Overall, DNA methylation changes significantly during disease progression and between cytogenetic subgroups.

Impact of Ultra High-risk Genetics on Real-world Outcomes of Transplant-eligible Multiple Myeloma Patients.

Refined prediction of early relapse following standard-of-care (SoC) autologous stem cell transplant (ASCT) in newly diagnosed multiple myeloma (NDMM) could inform real-world risk-stratified post-ASCT strategies. We investigated the impact of double hit genetics (≥2 adverse markers: t(4;14), t(14;16), t(14;20), gain(1q), del(17p)) on outcome in 139 NDMM patients who underwent SoC ASCT between January 2014 and October 2019 at our center. Double hit genetics were associated with a significantly shortened progression-free survival (hazard ratio [HR] = 4.27, P < 0.001) and overall survival (HR = 4.01, P = 0.03), and characterized most early relapses. Our results support the real-world utility of extended genetic profiling for improved risk prediction in NDMM.

Maintenance lenalidomide in newly diagnosed transplant eligible and non-eligible myeloma patients; profiling second primary malignancies in 4358 patients treated in the Myeloma XI Trial.

Background: Early trials of long-term lenalidomide use reported an increased incidence of second primary malignancy (SPM), including acute myeloid leukaemia and myelodysplastic syndrome. Later, meta-analysis suggested the link to be secondary to lenalidomide in combination with melphalan. Methods: Myeloma XI is a large, phase III randomised trial in-which lenalidomide was used at induction and maintenance, in transplant eligible (TE) and non-eligible (TNE) newly diagnosed patients (NCT01554852). Here we present an analysis of SPM incidence and profile the SPM type to determine the impact of autologous stem cell transplantation (ASCT) and lenalidomide exposure in 4358 patients treated on study. Data collection took place from the start of the trial in May 2010, to May 2019, as per the protocol timeline. The Median follow-up following maintenance randomisation was 54.5 and 46.1 months for TE and TNE patients, respectively. Findings: In the TE pathway, the overall SPM incidence was 7.7% in lenalidomide maintenance patients compared to 3.2% in those being observed (p = 0.006). Although the TNE lenalidomide maintenance patients had the greatest SPM incidence (15.4%), this was not statistically significant when compared to the observed patients (10%, p = 0.10).The SPM incidence was higher in patients who received lenalidomide at induction and maintenance (double exposure), when compared to those treated with lenalidomide at one time point (single exposure). Again, this was most marked in TNE patients where the overall SPM incidence was 16.9% in double exposed patients, compared to 11.7% in single exposed patients, and 11.2% in patients who did not receive lenalidomide (p = 0.04). This is likely an effect of treatment duration, with the median number of cycles being 27 in the TNE double exposed patients, vs 6 in the single exposure patients.Haematological SPMs were uncommon, diagnosed in 50 patients (incidence 1.1%). The majority of cases were diagnosed in TE patients treated with lenalidomide maintenance (n = 25, incidence 2.8%), suggesting a possible link with melphalan. Non-melanoma skin cancer incidence was highest in patients receiving lenalidomide maintenance, particularly in TNE patients, where squamous cell carcinoma and basal cell carcinoma were diagnosed in 5.5% and 2.6% of patients, respectively. The incidence of most solid tumour types was higher in lenalidomide maintenance patients.Mortality due to progressive myeloma was reduced in patients receiving lenalidomide maintenance, noted to be 16.6% compared 22.6% in those observed in TE patients and 32.7% compared to 41.5% in TNE patients. SPM related mortality was low, 1.8% and 6.1% in TE and TNE lenalidomide maintenance patients, respectively, compared to 0.4% and 2.8% in those being observed. Interpretation: This provides reassurance that long-term lenalidomide treatment is safe and associated with improved outcomes in TE and TNE populations, although monitoring for SPM development should be incorporated into clinic review processes. Funding: Primary financial support was from Cancer Research UK [C1298/A10410].

A compendium of myeloma-associated chromosomal copy number abnormalities and their prognostic value.

To obtain a comprehensive genomic profile of presenting multiple myeloma cases we performed high-resolution single nucleotide polymorphism mapping array analysis in 114 samples alongside 258 samples analyzed by U133 Plus 2.0 expression array (Affymetrix). We examined DNA copy number alterations and loss of heterozygosity (LOH) to define the spectrum of minimally deleted regions in which relevant genes of interest can be found. The most frequent deletions are located at 1p (30%), 6q (33%), 8p (25%), 12p (15%), 13q (59%), 14q (39%), 16q (35%), 17p (7%), 20 (12%), and 22 (18%). In addition, copy number-neutral LOH, or uniparental disomy, was also prevalent on 1q (8%), 16q (9%), and X (20%), and was associated with regions of gain and loss. Based on fluorescence in situ hybridization and expression quartile analysis, genes of prognostic importance were found to be located at 1p (FAF1, CDKN2C), 1q (ANP32E), and 17p (TP53). In addition, we identified common homozygously deleted genes that have functions relevant to myeloma biology. Taken together, these analyses indicate that the crucial pathways in myeloma pathogenesis include the nuclear factor-κB pathway, apoptosis, cell-cycle regulation, Wnt signaling, and histone modifications. This study was registered at http://isrctn.org as ISRCTN68454111.

The clinical impact and molecular biology of del(17p) in multiple myeloma treated with conventional or thalidomide-based therapy.

Hemizygous deletion of 17p (del(17p)) has been identified as a variable associated with poor prognosis in myeloma, although its impact in the context of thalidomide therapy is not well described. The clinical outcome of 85 myeloma patients with del(17p) treated in a clinical trial incorporating both conventional and thalidomide-based induction therapies was examined. The clinical impact of deletion, low expression, and mutation of TP53 was also determined. Patients with del(17p) did not have inferior response rates compared to patients without del(17p), but, despite this, del(17p) was associated with impaired overall survival (OS) (median OS 26.6 vs. 48.5 months, P < 0.001). Within the del(17p) group, thalidomide induction therapy was associated with improved response rates compared to conventional therapy, but there was no impact on OS. Thalidomide maintenance was associated with impaired OS, although our analysis suggests that this effect may have been due to confounding variables. A minimally deleted region on 17p13.1 involving 17 genes was identified, of which only TP53 and SAT2 were underexpressed. TP53 was mutated in <1% in patients without del(17p) and in 27% of patients with del(17p). The higher TP53 mutation rate in samples with del(17p) suggests a role for TP53 in these clinical outcomes. In conclusion, del(17p) defined a patient group associated with short survival in myeloma, and although thalidomide induction therapy was associated with improved response rates, it did not impact OS, suggesting that alternative therapeutic strategies are required for this group.

Novel drugs in myeloma: harnessing tumour biology to treat myeloma.

Steroids and alkylating agents have formed the backbone of myeloma therapy for decades with the result that patient outcomes improved very little over this period. The situation has changed recently with the advent of immunomodulatory agents and bortezomib, and patient outcomes are now improving. The introduction of bortezomib can be viewed as particularly successful as it was designed in the laboratory to fit a target that had been identified through biological research. As such, it has formed the template for new drug discovery in myeloma, with an increased understanding of the biology of the myeloma cell leading to the definition of upregulated pathways which are then targeted with a specific agent. This chapter will examine novel agents currently in development in the context of the abnormal biology of the myeloma cell and its microenvironment.

Understanding the molecular biology of myeloma and its therapeutic implications.

Myeloma develops due to the accumulation of multiple pathological genetic events, many of which have been defined. Hyperdiploidy and reciprocal translocations centered on the immunoglobulin heavy chain variable region constitute primary genetic lesions. These primary lesions co-operate with secondary genetic events including chromosomal deletions and gains, gene mutations and epigenetic modifiers such as DNA methylation to produce the malignant phenotype of myeloma. Some of these events have been linked with distinct clinical outcome and can be used to define patient groups. This review explores the molecular biology of myeloma and identifies how genetic lesions can be used to define high- and low-risk patient groups, and also defines potential targets for therapy. The authors also explore how this information can be used to guide therapeutic decision-making and the design and interpretation of clinical trials, both now and in the future.

Mapping of chromosome 1p deletions in myeloma identifies FAM46C at 1p12 and CDKN2C at 1p32.3 as being genes in regions associated with adverse survival.

PURPOSE: Regions on 1p with recurrent deletions in presenting myeloma patients were examined with the purpose of defining the deletions and assessing their survival impact. EXPERIMENTAL DESIGN: Gene mapping, gene expression, FISH, and mutation analyses were conducted on patient samples from the MRC Myeloma IX trial and correlated with clinical outcome data. RESULTS: 1p32.3 was deleted in 11% of cases, and deletion was strongly associated with impaired overall survival (OS) in patients treated with autologous stem cell transplant (ASCT). In patients treated less intensively, del(1)(p32.3) was not associated with adverse progression-free survival (PFS) or OS. The target of homozygous deletions was CDKN2C, however its role in the adverse outcome of cases with hemizygous deletion was less certain. 1p22.1-21.2 was the most frequently deleted region and contained the candidate genes MTF2 and TMED5. No mutations were identified in these genes. 1p12 was deleted in 19% of cases, and deletion was associated with impaired OS in univariate analysis. The target of homozygous deletion was FAM46C, which was mutated in 3.4% of cases. When cases with FAM46C deletion or mutation were considered together, they were strongly associated with impaired OS in the intensive treatment setting. CONCLUSION: Deletion of 1p32.3 and 1p12 was associated with impaired OS in myeloma patients receiving ASCT. FAM46C was identified as a gene with potential pathogenic and prognostic significance based on the occurrence of recurrent homozygous deletions and mutations.

Gender disparities in the tumor genetics and clinical outcome of multiple myeloma.

BACKGROUND: Several cancer types have differences in incidence and clinical outcome dependent on gender, but these are not well described in myeloma. The aim of this study was to characterize gender disparities in myeloma. METHODS: We investigated the association of gender with the prevalence of tumor genetic lesions and the clinical outcome of 1,960 patients enrolled in the phase III clinical trial MRC Myeloma IX. Genetic lesions were characterized by FISH. RESULTS: Disparities were found in the prevalence of primary genetic lesions with immunoglobulin heavy chain gene (IGH) translocations being more common in women (50% of female patients vs. 38% of male patients, P < 0.001) and hyperdiploidy being more common in men (50% female vs. 62% male, P < 0.001). There were also differences in secondary genetic events with del(13q) (52% female vs. 41% male, P < 0.001) and +1q (43% female vs. 36% male, P = 0.042) being found more frequently in female myeloma patients. Female gender was associated with inferior overall survival (median: 44.8 months female vs. 49.9 months male, P = 0.020). CONCLUSIONS: We found gender-dependent differences in the prevalence of the primary genetic events of myeloma, with IGH translocations being more common in women and hyperdiploidy more common in men. This genetic background may impact subsequent genetic events such as +1q and del(13q), which were both more frequent in women. The higher prevalence of lesions associated with poor prognosis in the female myeloma population, such as t(4;14), t(14;16) and +1q, may adversely affect clinical outcome. IMPACT: These differences suggest that gender influences the primary genetic events of myeloma.

Homozygous deletion mapping in myeloma samples identifies genes and an expression signature relevant to pathogenesis and outcome.

PURPOSE: Myeloma is a clonal malignancy of plasma cells. Poor-prognosis risk is currently identified by clinical and cytogenetic features. However, these indicators do not capture all prognostic information. Gene expression analysis can be used to identify poor-prognosis patients and this can be improved by combination with information about DNA-level changes. EXPERIMENTAL DESIGN: Using single nucleotide polymorphism-based gene mapping in combination with global gene expression analysis, we have identified homozygous deletions in genes and networks that are relevant to myeloma pathogenesis and outcome. RESULTS: We identified 170 genes with homozygous deletions and corresponding loss of expression. Deletion within the "cell death" network was overrepresented and cases with these deletions had impaired overall survival. From further analysis of these events, we have generated an expression-based signature associated with shorter survival in 258 patients and confirmed this signature in data from two independent groups totaling 800 patients. We defined a gene expression signature of 97 cell death genes that reflects prognosis and confirmed this in two independent data sets. CONCLUSIONS: We developed a simple 6-gene expression signature from the 97-gene signature that can be used to identify poor-prognosis myeloma in the clinical environment. This signature could form the basis of future trials aimed at improving the outcome of poor-prognosis myeloma.