Molecular profiling of immunoglobulin heavy-chain gene rearrangements unveils new potential prognostic markers for multiple myeloma patients

Multiple myeloma is a heterogeneous disease whose pathogenesis has not been completely elucidated. Although B-cell receptors play a crucial role in myeloma pathogenesis, the impact of clonal immunoglobulin heavy-chain features in the outcome has not been extensively explored. Here we present the characterization of complete heavy-chain gene rearrangements in 413 myeloma patients treated in Spanish trials, including 113 patients characterized by next-generation sequencing. Compared to the normal B-cell repertoire, gene selection was biased in myeloma, with significant overrepresentation of IGHV3, IGHD2 and IGHD3, as well as IGHJ4 gene groups. Hypermutation was high in our patients (median: 8.8%). Interestingly, regarding patients who are not candidates for transplantation, a high hypermutation rate (≥7%) and the use of IGHD2 and IGHD3 groups were associated with improved prognostic features and longer survival rates in the univariate analyses. Multivariate analysis revealed prolonged progression-free survival rates for patients using IGHD2/IGHD3 groups (HR: 0.552, 95% CI: 0.361−0.845, p = 0.006), as well as prolonged overall survival rates for patients with hypermutation ≥7% (HR: 0.291, 95% CI: 0.137−0.618, p = 0.001). Our results provide new insights into the molecular characterization of multiple myeloma, highlighting the need to evaluate some of these clonal rearrangement characteristics as new potential prognostic markers

Flow cytometric immunobead assay for fast and easy detection of PML-RARA fusion proteins for the diagnosis of acute promyelocytic leukemia

The PML-RARA fusion protein is found in approximately 97% of patients with acute promyelocytic leukemia (APL). APL can be associated with life-threatening bleeding complications when undiagnosed and not treated expeditiously. The PML-RARA fusion protein arrests maturation of myeloid cells at the promyelocytic stage, leading to the accumulation of neoplastic promyelocytes. Complete remission can be obtained by treatment with all-trans-retinoic acid (ATRA) in combination with chemotherapy. Diagnosis of APL is based on the detection of t(15;17) by karyotyping, fluorescence in situ hybridization or PCR. These techniques are laborious and demand specialized laboratories. We developed a fast (performed within 4-5 h) and sensitive (detection of at least 10% malignant cells in normal background) flow cytometric immunobead assay for the detection of PML-RARA fusion proteins in cell lysates using a bead-bound anti-RARA capture antibody and a phycoerythrin-conjugated anti-PML detection antibody. Testing of 163 newly diagnosed patients (including 46 APL cases) with the PML-RARA immunobead assay showed full concordance with the PML-RARA PCR results. As the applied antibodies recognize outer domains of the fusion protein, the assay appeared to work independently of the PML gene break point region. Importantly, the assay can be used in parallel with routine immunophenotyping for fast and easy diagnosis of APL

The cryptic IRF2BP2-RARA fusion transforms hematopoietic stem/progenitor cells and induces retinoid-sensitive acute promyelocytic leukemia

Letter to the Editor.These data were presented in part at the 56th American Society of Hematology meeting, San Francisco, December 2014.Peer Reviewe

The Atapuerca Sites and the Ibeas Hominids

ABSTRACT:The Atapuerca railway Trench and Ibeas sites near Burgos, Spain, are cave fillings that include a series of deposits, ranging from below the Matuyama/Bruhnes reversal up to the end of Middle Pleistocene. The lowest fossil-bearing bed in the Trench contains an assemblage of large and small Mammals including Mimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta crocuta, Dama sp, and Megacerini; the uppermost assemblage includes Canis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinheimensis, E. c. germanicus, Pitymys subterraneus. Microtus arvalis agrestis, Pliomys lenki, and also Panthera toscana, Dicerorhinus hemitoecbus, Bison schoetensacki, which are equally present in the lowest level. The biostratigraphic correlation and dates of the sites are briefly discussed, as are the paleoclimatic interpretation of the Trench sequences. Stone artifacts are found in several layers; the earliest occurrences correspond to the upper beds containing Mimomys savini. A set of preserved human occupation floors has been excavated in the top fossil-bearing beds. The stone-tool assemblages of the upper levels are of upper-medial Acheulean to Charentian tradition. The rich bone breccia SH, in the Cueva Mayor-Cueva del Silo, Ibeas de Juarros, is a derived deposit, due to a mud flow that dispersed and carried the skeletons of many carnivores and humans. The taxa represented are, Ursus deningeri (largely dominant), Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Several traits of both mandibular and cranial remains are summarized. Preliminary attempts at dating suggest that the Ibeas fossil man, is older than the Last Interglacial, or Oxygen-isotope stage 5.RESUMEN: La Trinchera del ferrocarril de Atapuerca y yacimientos de Ibeas cerca de Burgos, España, son rellenos de cuevas que incluyen una serie de depósitos, que datan desde por debajo de la inversión Matuyama/Bruhnes hasta el final del Pleistoceno Medio. El nivel fosilífero de la Trinchera contiene un conjunto de grandes y pequeños Mamíferos incluyendo Mimomys savini, Pitymys gregaloides, Pliomys episcopalis, Crocuta Crocuta, Dama sp. y Megacerini; el conjunto más superior incluye Canis lupus, Lynx spelaea, Panthera (Leo) fossilis, Felis sylvestris, Equus caballus steinheimensis, E. c. germanicus, Pitymys subterraneus, Microtus arvalis agrestis, Pliomys lenki y también Panthera toscana, Dicerorhinus hemitoechus, Bison schoetensacki, que están igualmente presentes en el nivel más inferior. La correlación bioestratigráfica y las edades de los yacimientos se discuten brevemente, al igual que la interpretación paleoclimática de las secuencias de Trinchera. Los artefactos de piedra se encuentran en varios niveles, las primeras apariciones corresponden a los niveles superiores que contienen Mimomys savini. Se ha excavado un conjunto de suelos que preservan ocupación humana en la parte superior de los niveles fosilíferos. Los conjuntos de herramientas de piedra de los niveles superiores son del Achelense superior-medio a la tradición Charentiense. La rica brecha fosilífera SH, en la Cueva Mayor-Cueva del Silo, Ibeas de Juarros, es un depósito derivado, debido a un flujo de lodo que dispersó y transportó los esqueletos de muchos carnívoros y humanos. Los taxones representados son, Ursus deningeri (muy predominante), Panthera (Leo) fossilis, Vulpes vulpes, Homo sapiens var. Se resumen los rasgos de los restos mandibulares y craneales. Los intentos preliminares de datación sugieren que el hombre fósil de Ibeas, es más antiguo que el último Interglacial, o estadio de oxígeno isotópico 5.Peer reviewe

Liquid biopsy for molecular characterization of diffuse large B‐cell lymphoma and early assessment of minimal residual disease

Circulating tumour DNA (ctDNA) allows genotyping and minimal residual disease (MRD) detection in lymphomas. Using a next‐generation sequencing (NGS) approach (EuroClonality‐NDC), we evaluated the clinical and prognostic value of ctDNA in a series of R‐CHOP‐treated diffuse large B‐cell lymphoma (DLBCL) patients at baseline (n = 68) and after two cycles (n = 59), monitored by metabolic imaging (positron emission tomography combined with computed tomography [PET/CT]). A molecular marker was identified in 61/68 (90%) ctDNA samples at diagnosis. Pretreatment high ctDNA levels significantly correlated with elevated lactate dehydrogenase, advanced stage, high‐risk International Prognostic Index and a trend to shorter 2‐year progression‐free survival (PFS). Valuable NGS data after two cycles of treatment were obtained in 44 cases, and 38 achieved major molecular response (MMR; 2.5‐log drop in ctDNA). PFS curves displayed statistically significant differences among those achieving MMR versus those not achieving MMR (2‐year PFS of 76% vs. 0%, p < 0.001). Similarly, more than 66% reduction in ΔSUVmax by PET/CT identified two subgroups with different prognosis (2‐year PFS of 83% vs. 38%; p < 0.001). Combining both approaches MMR and ΔSUVmax reduction, a better stratification was observed (2‐year PFS of 84% vs. 17% vs. 0%, p < 0.001). EuroClonality‐NDC panel allows the detection of a molecular marker in the ctDNA in 90% of DLBCL. ctDNA reduction at two cycles and its combination with interim PET results improve patient prognosis stratification

Molecular profiling of immunoglobulin heavy-chain gene rearrangements unveils new potential prognostic markers for multiple myeloma patients

Multiple myeloma is a heterogeneous disease whose pathogenesis has not been completely elucidated. Although B-cell receptors play a crucial role in myeloma pathogenesis, the impact of clonal immunoglobulin heavy-chain features in the outcome has not been extensively explored. Here we present the characterization of complete heavy-chain gene rearrangements in 413 myeloma patients treated in Spanish trials, including 113 patients characterized by next-generation sequencing. Compared to the normal B-cell repertoire, gene selection was biased in myeloma, with significant overrepresentation of IGHV3, IGHD2 and IGHD3, as well as IGHJ4 gene groups. Hypermutation was high in our patients (median: 8.8%). Interestingly, regarding patients who are not candidates for transplantation, a high hypermutation rate (≥7%) and the use of IGHD2 and IGHD3 groups were associated with improved prognostic features and longer survival rates in the univariate analyses. Multivariate analysis revealed prolonged progression-free survival rates for patients using IGHD2/IGHD3 groups (HR: 0.552, 95% CI: 0.361−0.845, p = 0.006), as well as prolonged overall survival rates for patients with hypermutation ≥7% (HR: 0.291, 95% CI: 0.137−0.618, p = 0.001). Our results provide new insights into the molecular characterization of multiple myeloma, highlighting the need to evaluate some of these clonal rearrangement characteristics as new potential prognostic markers.This work was partially supported by the Instituto de Salud Carlos III (ISCIII), Spanish Ministry of Economy and Competitiveness PI15/01956, CIBERONC-CB16/12/00233, and “Una manera de hacer Europa” (Innocampus; CEI-2010-1-0010)”. M.G.-A., I.P.-C., and C.J. are supported by the Fundación Española de Hematología y Hemoterapia (FEHH, co-funded by Fundación Cris in the latter case), A.M. by the European Social Fund and the Spanish Education Council through the University of Salamanca, and M.E.S. by the ISCIII (CPII18/00028). All Spanish funding is co-sponsored by the European Union FEDER program.Peer reviewe