ALBERT

Beschreibung: Diffuse large B-cell lymphomas (DLBCLs) can be divided into germinal-center B cell–like (GCB) and activated-B cell–like (ABC) subtypes by gene-expression profiling (GEP), with the latter showing a poorer outcome. Although this classification can be mimicked by different immunostaining algorithms, their reliability is the object of controversy. We constructed tissue microarrays with samples of 157 DLBCL patients homogeneously treated with immunochemotherapy to apply the following algorithms: Colomo (MUM1/IRF4, CD10, and BCL6 antigens), Hans (CD10, BCL6, and MUM1/IRF4), Muris (CD10 and MUM1/IRF4 plus BCL2), Choi (GCET1, MUM1/IRF4, CD10, FOXP1, and BCL6), and Tally (CD10, GCET1, MUM1/IRF4, FOXP1, and LMO2). GEP information was available in 62 cases. The proportion of misclassified cases by immunohistochemistry compared with GEP was higher when defining the GCB subset: 41%, 48%, 30%, 60%, and 40% for Colomo, Hans, Muris, Choi, and Tally, respectively. Whereas the GEP groups showed significantly different 5-year progression-free survival (76% vs 31% for GCB and activated DLBCL) and overall survival (80% vs 45%), none of the immunostaining algorithms was able to retain the prognostic impact of the groups (GCB vs non-GCB). In conclusion, stratification based on immunostaining algorithms should be used with caution in guiding therapy, even in clinical trials.

Beschreibung: Abstract 2647 We have reported in B-NHL cell lines that the p38 MAPK was constitutively activated and was involved in the regulation of tumor cell resistance to cytotoxic drugs. Further, inhibition of this pathway reversed drug resistance. Based in these findings we hypothesized that the activation of the p38 MAPK pathway in patients with B-NHL may be associated with unresponsiveness to cytotoxic drug therapy. This study was designed to test this hypothesis. Eighty patients with Diffused Large B Cell Lymphoma (DLBCL) were used for analysis. Freshly derived tumor tissues from these patients were obtained from biopsies prior to any treatment. Tissue microarrays were prepared and examined by immunohistochemistry for the expression of both p38 MAPK and phosphorylated p38 MAPK (active). The antibodies were tested for specificity. The frequency of stained cells

Beschreibung: Abstract 3951 Aim: The aims of this study were on one hand, to evaluate the significance of achieving molecular response (MR) by fluorescent-PCR (F-PCR) of Ig genes in a prospective way, particularly in patients with singular cytogenetics' features. On the other hand, to compared MR with immunophenotypic response (IR) and complete remission by immunofixation (CR). Patients: 130 new MM patients who had achieved CR or VGPR were analyzed by PCR, multiparametric flow cytometry (MFC) and immunofixation at diagnosis, and after induction therapy or transplantation: 48 patients received conventional chemotherapy as induction therapy followed with ASCT and were included in the GEM2000 trial and the other 82 patients were enrolled in the GEM2005 clinical trials in which the induction and maintenance therapy were based on Bortezomib and/or Thalidomide. Methods: The molecular analysis of Immunoglobulin (Ig) gene rearrangements at diagnosis was carried out by fluorescent PCR in DNA from bone marrow samples according to the Biomed-2 protocols. Briefly three different multiplex PCRs: DHJ; Ig Kappa light chain (IGK) rearrangements K-VJ and Kappa deleting element (KDE). DHJ and light chain rearrangements detected at the diagnosis were used in the follow-up. The sensitivity of PCR was between 1/103 and 1/104 as Martínez P. et al previously published in BJH, 2008. Regarding MFC the following monoclonal antibody combinations (FITC/PE/PerCP-Cy5.5/APC) were used at the diagnosis to identify different aberrant plasma cells phenotypes which were used as patient-specific probes for Minimal Residual Disease. Results: 64 patients had negative F-PCR and 66 patients had positive F-PCR after induction therapy. The OS was 77.32% and 59.18%, respectively and the medians OS were 116 and 67 months for each group (P= 0.03). Regarding the PFS, 28 of the 64 F-PCR negative patients relapsed while there were 44 relapses in the group of positive F-PCR. The 5y PFS was 56.44% and 27.43% respectively; the medians PFS were 60 and 36 months respectively (P= 0.0005). The multivariate analysis showed that achieving molecular response by F-PCR had a independent prognostic value in PFS (P=0.003, HR 2.3). Interestingly amongst patients who achieved CR, F-PCR identified a population of patient with a better PFS, figure A (P= 0.04, HR 2.179).The applicability of the F-PCR was almost equivalent to that observed by MFC (91.5 vs. 92%). Nevertheless we found discordant results between these two response criteria. Approximately the 20% of patients who had achieved a MR no obtained IR. The opposite pattern also was observed (IR/noMR) in 10% of the patients. In order to see if the PCR showed differences in terms of survival in patients with high or low risk cytogenetics features at the diagnosis, we made two independent analysis: in one hand we analyzed 14 patients with high-risk cytogenetics [t(4;14), t(14;16) and/or del(17p)] and on the other hand 72 patients with standard-risk cytogenetics. In the former analysis, 4 of the 8 who had negative F-PCR relapsed after the induction therapy while the totality of the other six with positive F-PCR did. The medians PFS were 32 and 17 months respectively (P= 0.0002). In connection with the 72 patients with standard-risk cytogenetics, 13 of the 34 who had negative F-PCR relapsed while 24 of the 38 with positive F-PCR did. The medians PFS times were 75 and 38 months respectively, figure B (P= 0.01). Conclusion: F-PCR of IgH rearrangements is a simple, cheap and feasible method for evaluating response in MM patients after induction therapy or transplantation. Additionally achieving MR provides a similar prognostic value to IR in patients differentially treated, and particularly in patients with singular cytogenetics' features as well as in patients with CR by immunofixation. Disclosures: Paiva: Jansen-Cillag: Honoraria; Celgene: Honoraria. Rosiñol:Janssen: Honoraria; Celgene: Honoraria. Alegre:Janssen: Honoraria; Celgene: Honoraria. Blade:Centocor Ortho Biotech Research & Development: Research Funding. San Miguel:Janssen-Cilag: Honoraria; Celgene: Honoraria. Lahuerta:Celgene: Honoraria; Janssen: Honoraria.

Beschreibung: The nuclear factor of activated T cells (NFAT) family of transcription factors plays important roles in many biologic processes, including the development and function of the immune and vascular systems. Cells usually express more than one NFAT member, raising the question of whether NFATs play overlapping roles or if each member has selective functions. Using mRNA knock-down, we show that NFATc3 is specifically required for IL2 and cyclooxygenase-2 (COX2) gene expression in transformed and primary T cells and for T-cell proliferation. We also show that NFATc3 regulates COX2 in endothelial cells, where it is required for COX2, dependent migration and angiogenesis in vivo. These results indicate that individual NFAT members mediate specific functions through the differential regulation of the transcription of target genes. These effects, observed on short-term suppression by mRNA knock-down, are likely to have been masked by compensatory effects in gene-knockout studies.

Beschreibung: Diffuse large B-cell lymphoma (DLBCL) prognostication requires additional biologic markers. miRNAs may constitute markers for cancer diagnosis, outcome, or therapy response. In the present study, we analyzed the miRNA expression profile in a retrospective multicenter series of 258 DLBCL patients uniformly treated with chemoimmunotherapy. Findings were correlated with overall survival (OS) and progression-free survival (PFS). miRNA and gene-expression profiles were studied using microarrays in an initial set of 36 cases. A selection of miRNAs associated with either DLBCL molecular subtypes (GCB/ABC) or clinical outcome were studied by multiplex RT-PCR in a test group of 240 cases with available formalin-fixed, paraffin-embedded (FFPE) diagnostic samples. The samples were divided into a training set (123 patients) and used to derive miRNA-based and combined (with IPI score) Cox regression models in an independent validation series (117 patients). Our model based on miRNA expression predicts OS and PFS and improves upon the predictions based on clinical variables. Combined models with IPI score identified a high-risk group of patients with a 2-year OS and a PFS probability of 〈 50%. In summary, a precise miRNA signature is associated with poor clinical outcome in chemoimmunotherapy-treated DLBCL patients. This information improves upon IPI-based predictions and identifies a subgroup of candidate patients for alternative therapeutic regimens.

Beschreibung: For establishing the true effect of different response categories in patients with multiple myeloma (MM) treated with autologous stem cell transplantation, we evaluated, after a median follow-up of 153 months, 344 patients with MM who received a transplant between 1989 and 1998. Overall survival (OS) at 12 years was 35% in complete response (CR) patients, 22% in near complete response (nCR), 16% in very good partial response (VGPR), and 16% in partial response (PR) groups. Significant differences in OS and progression-free survival were found between CR and nCR groups (P = .01 and P = .002, respectively), between CR and VGPR groups (P = .0001 and P = .003), or between CR and PR groups (P = .003 and P = 〈 10−5); no differences were observed between the nCR and VGPR groups (P = .2 and P = .9) or between these groups and the PR group (P = .1 and P = .8). A landmark study found a plateau phase in OS after 11 years; 35% patients in the CR group and 11% in the nCR+VGPR+PR group are alive at 17 years; 2 cases had relapsed in the nCR+VGPR+PR group. In conclusion, MM achieving CR after autologous stem cell transplantation is a central prognostic factor. The relapse rate is low in patients with 〉 11 years of follow-up, possibly signifying a cure for patients in CR.

Beschreibung: Many mammalian transcripts contain target sites for multiple miRNAs, although it is not clear to what extent miRNAs may coordinately regulate single genes. We have mapped the interactions between down-regulated miRNAs and overexpressed target protein-coding genes in murine and human lymphomas. Myc, one of the hallmark oncogenes in these lymphomas, stands out as the up-regulated gene with the highest number of genetic interactions with down-regulated miRNAs in mouse lymphomas. The regulation of Myc by several of these miRNAs is confirmed by cellular and reporter assays. The same approach identifies MYC and multiple Myc targets as a preferential target of down-regulated miRNAs in human Burkitt lymphoma, a pathology characterized by translocated MYC oncogenes. These results indicate that several miRNAs must be coordinately down-regulated to enhance critical oncogenes, such as Myc. Some of these Myc-targeting miRNAs are repressed by Myc, suggesting that these tumors are a consequence of the unbalanced activity of Myc versus miRNAs.