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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.

Despite improvement in the treatment of advanced classical Hodgkin lymphoma, approximately 30% of patients relapse or die as result of the disease. Current predictive systems, determined by clinical and analytical parameters, fail to identify these high-risk patients accurately. We took a multistep approach to design a quantitative reverse-transcription polymerase chain reaction assay to be applied to routine formalin-fixed paraffin-embedded samples, integrating genes expressed by the tumor cells and their microenvironment. The significance of 30 genes chosen on the basis of previously published data was evaluated in 282 samples (divided into estimation and validation sets) to build a molecular risk score to predict failure. Adequate reverse-transcription polymerase chain reaction profiles were obtained from 262 of 282 cases (92.9%). Best predictor genes were integrated into an 11-gene model, including 4 functional pathways (cell cycle, apoptosis, macrophage activation, and interferon regulatory factor 4) able to identify low- and high-risk patients with different rates of 5-year failure-free survival: 74% versus 44.1% in the estimation set (P < .001) and 67.5% versus 45.0% in the validation set (P = .022). This model can be combined with stage IV into a final predictive model able to identify a group of patients with very bad outcome (5-year failure-free survival probability, 25.2%).

Around 20% to 30% of patients with Hodgkin lymphoma (HL) do not benefit from standard therapies and finally succumb to their disease. The factors that influence the outcome of HL have not been elucidated, underscoring the demand for the identification of biologic risk factors and new therapeutic targets. We analyzed the gene expression profiles of samples from 29 patients with advanced classic HL treated with standard therapy and compared the expression profiles of patients with favorable and unfavorable clinical outcome. Using supervised methods, we identified 145 genes associated with outcome, which were grouped into 4 signatures representing genes expressed by either the tumoral cells (genes involved in the regulation of mitosis and cell growth/apoptosis) or the tumor microenvironment. The relationship between the expression of 8 representative genes and survival was successfully validated in an independent series of 235 patients by quantification of protein expression levels on tissue microarrays. Analysis of centrosomes and mitotic checkpoint confirmed the existence of an abnormal transition through mitosis in HL cells. Therefore, genes related to tumor microenvironment, cell growth/apoptosis, and regulation of mitosis are associated with treatment response and outcome of patients with HL.

p18INK4c is a cyclin-dependent kinase (CDK) inhibitor that interferes with the Rb-kinase activity of CDK6/CDK4. Disruption of p18INK4c in mice impairs B-cell terminal differentiation and confers increased susceptibility to tumor development; however, alterations of p18INK4c in human tumors have rarely been described. We used a tissue-microarray approach to analyze p18INK4c expression in 316 Hodgkin lymphomas (HLs). Nearly half of the HL cases showed absence of p18INK4c protein expression by Reed-Sternberg (RS) cells, in contrast with the regular expression of p18INK4c in normal germinal center cells. To investigate the cause of p18INK4c repression in RS cells, the methylation status of the p18INK4c promoter was analyzed by methylation-specific polymerase chain reaction (PCR) and bisulfite sequencing. Hypermethylation of the p18INK4c promoter was detected in 2 of 4 HL-derived cell lines, but in none of 7 non-Hodgkin lymphoma (NHL)-derived cell lines. We also detected p18INK4c hypermethylation, associated with absence of protein expression, in 5 of 26 HL tumors. The correlation of p18INK4c immunostaining with the follow-up of the patients showed shorter overall survival in negative cases, independent of the International Prognostic Score. These findings suggest that p18INK4c may function as a tumor suppressor gene in HL, and its inactivation may contribute to the cell cycle deregulation and defective terminal differentiation characteristic of the RS cells.

Tumoral cells in Hodgkin lymphoma (HL) display an increased growth fraction and diminished apoptosis, implying a profound disturbance of the cell cycle and apoptosis regulation. However, limitations of molecular techniques have prevented the analysis of the tumor suppressor pathways and cell-cycle checkpoints. Tissue microarray (TMA) is a powerful tool for analyzing a large number of molecular variables in a large series of tumors, although the feasibility of this technique has not yet been demonstrated in heterogeneous tumors. The expression of 29 genes regulating the cell cycle and apoptosis were analyzed by immunohistochemistry and in situ hybridization in 288 HL biopsies using TMA. The sensitivity of the technique was validated by comparing the results with those obtained in standard tissue sections. The results revealed multiple alterations in different pathways and checkpoints, including G1/S and G2/M transition and apoptosis. Striking findings were the overexpression of cyclin E, CDK2, CDK6, STAT3, Hdm2, Bcl2, Bcl-X(L), survivin, and NF-kappaB proteins. A multiparametric analysis identified proteins associated with increased growth fraction (Hdm2, p53, p21, Rb, cyclins A, B1, D3, and E, CDK2, CDK6, SKP2, Bcl-X(L), survivin, STAT1, and STAT3), and proteins associated with apoptosis (NF-kappaB, STAT1, and RB). The analysis also demonstrated that Epstein-Barr virus (EBV)-positive cases displayed a characteristic profile, confirming the pathogenic role of EBV in HL. Survival probability depends on multiple biologic factors, including overexpression of Bcl2, p53, Bax, Bcl-X(L), MIB1, and apoptotic index. In conclusion, Hodgkin and Reed-Sternberg cells harbor concurrent and overlapping alterations in the major tumor suppressor pathways and cell-cycle checkpoints. This appears to determine the viability of the tumoral cells and the clinical outcome.

Background: Peripheral T-cell lymphomas (PTCL) account for about 10% of all lymphomas in Western countries. The aim of the present study is to analyze the initial characteristics and prognostic factors in a large series of PTCL patients., Patients and Methods: 174 patients (105 male/69 female; median age 61 years) were diagnosed with PTCL according to the R.E.A.L. Classification in nine Spanish institutions between 1985 and 1996. Cutaneous lymphomas and T-cell chronic lymphocytic/prolymphocytic leukemia were excluded from the study. Univariate and multivariate analyses were used to assess the prognostic value of the main initial variables., Results: The distribution according to histology subgroup was: PTCL unspecified, 95 cases (54.4%); anaplastic large-cell Ki-l-positive (ALCL), 30 cases (17%); angioimmunoblastic T cell, 22 cases (13%); angiocentric, 14 cases (8%); intestinal T cell, 12 cases (7%), and hepatosplenic gamma delta T cell, one case (0.6%). As compared to the other types, ALCL presented more frequently in ambulatory performance status, without extranodal involvement, in early stage, normal serum beta 2-microglobulin (B2M) level and low-risk international prognostic index (IPI). Most patients were treated with adriamycin-containing regimens. The overall CR rate was 49% (69% for ALCL vs. 45% for other PTCL; P < 0.02). The risk of relapse was 48% at four years. Median survival of the series was 22 months (65 months for ALCL vs. 20 months for other PTCL; P = 0.03), with a four-year probability of survival of 38% (95% confidence intervals (95% CI): 28-48). In the univariate analysis, in addition to the histology, older age, poor performance status, presence of B-symptoms, extranodal involvement, bone marrow infiltration, advanced Ann Arbor stage, high serum LDH, high serum B2M, and intermediate- or high-risk IPI were related to poor survival. In the multivariate analysis the histologic subgroup (ALCL vs. other PTCL) (P = 0.02; response rate (RR): 4.3), the presence of B-symptoms (P = 0.02, RR: 2.2), and the IPI (low vs. high) (P = 0.04, RR: 2) maintained independent predictive value. When the analysis was restricted to the unspecified subtype, only IPI had independent prognostic value (P = 0.003; RR: 3.5)., Conclusions: PTCL have adverse prognostic features at diagnosis, respond poorly to therapy and have short survival, with no sustained remission. ALCL constitutes a subgroup which responds better to therapy and has a longer survival.

Background: Gastric MALT lymphoma can be histologically classified into two groups, low-grade (LG) and high-grade (HG); however, their natural history is poorly understood. We have studied a large retrospective series aiming to confirm whether the histological groups confer different clinical features and behavior and to analyze the prognostic factors in these patients., Patients and Methods: A series of 143 gastric B-cell MALT lymphomas is reported. Eighty-four were low-grade lymphomas (LG) and 59 were high-grade lymphomas (HG). Median follow-up was 36 months. The clinical and analytical parameters of the 84 LG patients were compared with those of the 59 HG patients. In the patients who had been operated on, the pathological features (macroscopical patterns, tumor size, involvement of resection margins, degree of parietal invasion and involvement of abdominal lymph nodes and adjacent viscera) of the LG patients were compared with those of the HG patients. The sites of relapses were studied. In the 132 treated and followed-up patients the influence of the treatment and that of clinical, analytical and pathological features on survival were investigated with the Kaplan and Meier and log-rank tests. To identify the factors with independent influence on survival, a Cox model was fitted for the whole series and separately for 53 HG patients., Results: HG group differed from the LG group by a significantly higher frequency of weight loss at presentation, palpable abdominal mass, hepatomegaly, peripheral lymphadenopathy, elevated serum LDH, higher incidence of stage III-IV and tumor/mass patterns in the endoscopy and in the gastrectomy specimen. The tumor was significantly larger in the HG group than in the LG and the deeper invasion of the gastric wall, the higher frequency of infiltration of the abdominal lymph nodes and the visceral extension were also significant in the HG group. Complete remission (CR) was achieved in 91% of the patients of the LG group, but was significantly lower, 70%, in the HG group. Relapses occurred in the stomach and also in non-MALT sites. In 132 treated and followed-up patients, elevated serum LDH, absence of CR, HG group and stage III-IV were associated with a worse survival. In the Cox multivariate model, stage was the only variable influencing survival, although stage was related to the histological grade. In the HG group, stage was also an independent significant risk factor, whereas treatment with surgery, chemotherapy or both was not. In the 103 patients treated with surgery, a worse survival was associated with the involvement of the resection borders, depth of the infiltration of the gastric wall, dissemination to distant abdominal nodes and adjacent organs, but not with the addition of chemotherapy., Conclusions: Histological classification into LG and HG separates distinctive groups of gastric MALT lymphoma that show striking clinical and prognostic differences. Besides histological grade, stage is the most important prognostic feature.

A 75-year-old patient presented with a superior vena cava syndrome (SVCS) lasting 3 years. A prostatic carcinoma was found and a supraclavicular lymph node biopsy specimen disclosed metastasis of the prostatic carcinoma. Antiandrogen and luteinizing hormone-releasing hormone analogue therapy produced a marked improvement. Prostatic carcinoma, although a very rare cause, must be considered in the diagnosis of cases of SVCS with a protracted course, since it is a treatable disease.