Natalia Tovar

Impact of MiRSNPs on Survival and Progression in Patients with Multiple Myeloma Undergoing Autologous Stem Cell Transplantation

Purpose: A distinctive new group of polymorphisms is constituted by single-nucleotide polymorphism (SNP) in miRNA processing machinery in miRNA precursor molecules and in miRNA-binding sites, known as miRSNPs. The aim of this study was to ascertain the prognostic impact of six miRSNPs in patients with multiple myeloma and analyze the functional consequences. Experimental Design: One hundred and thirty-seven patients with chemosensitive multiple myeloma (73M/64F) intensified with autologous stem cell transplantation (ASCT) were studied. The median follow-up was 4 years. The genes and SNPs evaluated in genomic DNA by allelic discrimination were KRT81 (rs3660), AFF1 (rs17703261), FAM179b (rs1053667), and MIR196A2 (rs11614913) for miRNA target genes and TRBP (rs784567) and XPO5 (rs11077) for miRNA biogenesis pathway. Results: Overall survival (OS) was significantly longer in patients with KRT81 rs3660 C/C variant (P = 0.037). Functional analysis showed that the presence of C variant in KRT81 3′ untranslated region (UTR) is related with a reduction of the protein levels. Moreover, the reduction of KRT81 protein levels by siRNA in multiple myeloma cell lines is related to a decreased proliferation. On the other hand, OS was significantly longer in patients with C/C or A/C variant in XPO5 rs11077 (P = 0.012). There was also a significantly longer progression-free survival (PFS) for this SNP (P = 0.013). This SNP retained its prognostic impact on PFS and OS in a multivariate regression analysis (P = 0.028 and P = 0.014, respectively). Conclusion: This is the first report that relates miRSNPs with prognosis in multiple myeloma either in a keratin gene (KRT81), target of diverse miRNA multiple myeloma clusters, or in the miRNA biogenesis pathway–related protein exportin-5. Clin Cancer Res; 18(13); 3697–704. ©2012 AACR.

Emergence of oligoclonal bands in patients with multiple myeloma in complete remission after induction chemotherapy: association with the use of novel agents.

The emergence of oligoclonal bands is associated with a favorable outcome after autologous stem cell transplantation in multiple myeloma. The aim of this study was to determine the prevalence of immunoglobulin oligoclonality in 33 patients with multiple myeloma in complete remission achieved with primary therapy with either cytotoxic agents (n=18, 54.5%) or new induction regimens incorporating novel drugs (n=15, 45.4%). Eleven patients (33.3%) developed oligoclonal bands. In the group treated with novel agents, this oligoclonal immune response was observed in 60% (9 of 15) of the patients versus only 11.1% (2 of 18) of those given cytotoxic therapy (P=0.003). This is the first report showing a different frequency of oligoclonal humoral response in patients in complete remission achieved after conventional cytotoxic therapy versus induction incorporating novel agents. This difference could be due to a higher antitumor effect associated with the use of novel drugs, a stronger immune reconstitution, or both.

Natural history and prognostic impact of oligoclonal humoral response in patients with multiple myeloma after autologous stem cell transplantation: long-term results from a single institution

The emergence of an oligoclonal humoral response, resulting in the appearance of a different serum M-protein to that observed at diagnosis is a well-recognized event after autologous stem cell transplantation in multiple myeloma in complete response, and it has been considered to be a benign phenomenon. The aim of the present study was to investigate the incidence, biological characteristics and prognostic value of the oligoclonal bands in patients with myeloma who underwent autologous transplantation at our institution in the last 18 years. We proceed with a retrospective systematic review of all serum and urine immunofixation studies performed in the 211 patients with multiple myeloma who underwent melphalan-based autologous transplantation. Oligoclonal bands were observed in 34% of the patients, with a significantly higher prevalence with the use of novel agents versus conventional chemotherapy in induction (63% vs. 22%; P=0.0001). The incidence of oligoclonal bands was most frequent in non-IgG isotype, particularly in light chain only myeloma. The oligoclonal phenomenon was almost exclusive to patients in complete remission compared to other degrees of response (87% vs. 13%; P=0.0001), and lasted for a median of 1.35 years, persisting during follow up in all patients except in those who relapsed. In prognostic terms, the presence of oligoclonality resulted in a significantly longer progression-free and overall survival. Patients with oligoclonal humoral response lasting for more than one year after transplantation had a significantly longer clinical progression-free and overall survival than those with shorter duration (P=0.008 and P=0.0001, respectively), likely reflecting the importance of a robust humoral immune response.

Bortezomib/dexamethasone followed by autologous stem cell transplantation as front line treatment for light‐chain deposition disease

Limited data has been published on the treatment results in patients with light‐chain deposition disease (LCDD). Whenever possible, high‐dose melphalan followed by autologous stem cell transplantation (ASCT) has been the first treatment option, achieving somehow better results than conventional therapy. However, and based on the promising results obtained by treating patients with light‐chain amyloidosis with bortezomib/dexamethasone, new treatment options appear in LCDD. Herein, we describe three patients with LCDD treated with bortezomib/dexamethasone followed by high‐dose melphalan and autologous transplantation. We believe that this new approach should be the treatment of choice in this disease. In addition, those patients achieving hematologic complete response after ASCT could benefit from a kidney transplant if the renal impairment requiring dialysis persists.

Impact on response and survival of DNA repair single nucleotide polymorphisms in relapsed or refractory multiple myeloma patients treated with thalidomide.

Single nucleotide polymorphisms (SNPs) in 12 genes involving multidrug resistance, drug metabolic pathways, DNA repair systems and cytokines were examined in 28 patients with relapsed/refractory multiple myeloma (MM) treated with single agent thalidomide and the results were correlated with response, toxicity and overall survival (OS). The response rate was higher in patients with SNPs in ERCC1 (rs735482) (p=0.006), ERCC5 (rs17655) (p=0.04) or XRCC5 (rs1051685) (p=0.013). Longer OS was associated with the SNP in ERCC1 (rs735482) (p=0.005) and XRCC5 (rs1051685) (p=0.02). Finally, polymorphism in GSTT1 (rs4630) was associated with a lower frequency of thalidomide-induced peripheral neuropathy (p=0.04).

Pattern of relapse and progression after autologous SCT as upfront treatment for multiple myeloma.

The achievement of CR is the crucial step for a prolonged PFS and OS after an autologous SCT in multiple myeloma (MM). Unfortunately, even with the use of new regimens and the current high CR rates, most, if not all, patients will ultimately relapse or progress. We analyzed the type of relapse or progression (asymptomatic vs symptomatic), clinical features including the presence of extramedullary involvement and time to next treatment in 211 patients who underwent melphalan-based autologous SCT over an 18-year period at our institution. After autologous SCT, serological or asymptomatic relapse/progression was observed in about one half of the patients. The treatment-free interval was significantly longer in patients relapsing from CR than in those progressing from PR (P=0.017). Patients with serological relapse/progression had a significantly longer OS than those relapsing from symptomatic disease (P=0.002). The relapse pattern was similar to the initial clinical presentation. Survival after relapse/progression was shorter in those patients with a 24-h urine M-protein excretion of at least 200 mg (P=0.048). Extramedullary involvement was frequent (24%), being the highest risk in patients with extramedullary involvement at diagnosis (P=0.001).

Impact of global and gene-specific DNA methylation pattern in relapsed multiple myeloma patients treated with bortezomib

We studied seventy-five patients with relapsed MM treated with bortezomib-based regimens. DNA was isolated from bone marrow samples at the time of relapse. Global methylation was determined by ELISA, and CpG island DNA methylation profile of 30 genes by a DNA methylation PCR system. Patients with more than 3.95% of total DNA methylated achieved better overall survival (OS) (p=0.004). A relatively low methylation percentage (<1.07%) of NFKB1 was also associated with longer OS after bortezomib treatment (p=0.015). The combination of highly methylated global genome with low NFKB1 methylation status defined a specific subset of patients with better prognosis.

Multiple Myeloma in Serologic Complete Remission after Autologous Stem Cell Transplantation: Impact of Bone Marrow Plasma Cell Assessment by Conventional Morphology on Disease Progression

The current definition of complete remission (CR) in multiple myeloma (MM) requires a negative serum and urine immunofixation (IFE) and <5% bone marrow plasma cells (BMPCs). The aim of this study was to determine the value of BMPCs count by standard microscopic evaluation in patients with MM in serologic CR after autologous stem cell transplantation (ASCT). Thirty-five patients with a median follow-up after ASCT of 7.3 years were studied. The percentage of BMPCs was an independent predictor of progression in multivariate model (hazard ratio 2.02, P = .009). Patients with >1.5% BMPCs (median: 0.8%) after ASCT had an increased risk of progression (P = .016) and a trend toward a shorter survival (P = .195). In conclusion, conventional morphology of bone marrow is a useful and rapid tool as a first step to assess the residual tumor mass in patients with MM in CR after ASCT, and it constitutes a strong predictor for disease progression.

Evolving M-protein pattern in patients with smoldering multiple myeloma: impact on early progression

Smoldering multiple myeloma (SMM) is a biologically heterogeneous, clinically defined entity with a variable rate of progression to symptomatic multiple myeloma (MM). Reliable markers for progression are critical for the development of potential therapeutic interventions. We retrospectively evaluated the predictive value of the evolving pattern of serum M-protein among other progression risk factors in 206 patients with SMM diagnosed between 1973 and 2012. Median time from recognition of evolving type to progression into symptomatic MM was 1.1 years (95% CI 0.5–2.0) and progression rate at 3 years was 71%. Development of the evolving type drastically worsened the prognostic estimation made at diagnosis for every covariate predictive of progression (serum M-protein size, bone marrow plasma cell infiltration, immunoparesis and Mayo Clinic risk). On average, the hazard ratio for progression to symptomatic MM increased to 5.1 (95% CI 3.4–7.6) after recognition of the evolving type. In conclusion, in patients with SMM the evolving pattern accurately predicts the risk of early progression to symptomatic disease, thereby allowing the identification of ultra-high risk patients who would be candidates for immediate therapy.

The BET bromodomain inhibitor CPI203 improves lenalidomide and dexamethasone activity in in vitro and in vivo models of multiple myeloma by blockade of Ikaros and MYC signaling

Most patients with multiple myeloma treated with current therapies, including immunomodulatory drugs, eventually develop relapsed/refractory disease. Clinical activity of lenalidomide relies on degradation of Ikaros and the consequent reduction in IRF4 expression, both required for myeloma cell survival and involved in the regulation of MYC transcription. Thus, we sought to determine the combinational effect of an MYC-interfering therapy with lenalidomide/dexamethasone. We analyzed the potential therapeutic effect of the combination of the BET bromodomain inhibitor CPI203 with the lenalidomide/dexamethasone regimen in myeloma cell lines. CPI203 exerted a dose-dependent cell growth inhibition in cell lines, indeed in lenalidomide/dexamethasone-resistant cells (median response at 0.5 μM: 65.4%), characterized by G1 cell cycle blockade and a concomitant inhibition of MYC and Ikaros signaling. These effects were potentiated by the addition of lenalidomide/dexamethasone. Results were validated in primary plasma cells from patients with multiple myeloma co-cultured with the mesenchymal stromal cell line stromaNKtert. Consistently, the drug combination evoked a 50% reduction in cell proliferation and correlated with basal Ikaros mRNA expression levels (P=0.04). Finally, in a SCID mouse xenotransplant model of myeloma, addition of CPI203 to lenalidomide/dexamethasone decreased tumor burden, evidenced by a lower glucose uptake and increase in the growth arrest marker GADD45B, with simultaneous downregulation of key transcription factors such as MYC, Ikaros and IRF4. Taken together, our data show that the combination of a BET bromodomain inhibitor with a lenalidomide-based regimen may represent a therapeutic approach to improve the response in relapsed/refractory patients with multiple myeloma, even in cases with suboptimal prior response to immunomodulatory drugs.