Immunophenotype and intermediate‐high international prognostic index score are prognostic factors for therapy in diffuse large B‐cell lymphoma patients

BACKGROUND.

The development of gene expression profiling and tissue microarray techniques have provided more information about the heterogeneity of diffuse large B‐cell lymphoma (DLBCL), enabling categorization of DLBCL patients into 3 prognostic groups according to cell origin (but independently from the International Prognostic Index [IPI] score): germinal center (GCB), activated B‐cell (ABC), and not classified (NC) diffuse large B‐cell lymphoma. This study investigated the role of immunohistochemical discrimination between GCB and ABC&NC‐DLBCL subtypes in identifying those high‐risk patients who may benefit from a more aggressive first‐line therapeutic approach.

METHODS.

From February 2003 to August 2006, 45 newly diagnosed DLBCL patients, with IPI≥2, were considered eligible for this study: 13 had a GCB, 8 an ABC, and 24 a NC‐DLBCL. GCB patients received 6 courses of rituximab, cyclophophosphamide, doxorubicin, vinicristine, and prednisone (R‐CHOP) chemotherapy, with a subsequent, autologous stem cell transplantation in case of partial response. All ABC and NC‐DLBCL patients received 6 R‐CHOP cycles and autologous stem cell transplantation.

RESULTS.

Complete response rate for each treatment arm was 84.6% for GCB and 89.7% for ABC&NC‐DLBCL (P = .50), with a continuous complete response rate of 81.8% and 84.6%, respectively (P = .59). Projected 4‐year overall survival is 100% for GCB and 82% for ABC&NC patients (P = .12). Progression‐free survival is 77% and 79% (P = .7), respectively.

CONCLUSIONS.

The autologous stem cell transplantation consolidation in the ABC&NC‐DLBCL subtypes induced the same rate of complete response (and similar progression‐free survival rate) compared with GCB‐DLBCL. In ABC&NC‐DLBCL patients the authors observed a complete response rate of 89.7% vs. 84.6% in the GCB‐DLBCL subset, without any significant difference in progression‐free survival rate. Cancer 2010. © 2010 American Cancer Society.     

Chromosome abnormalities in diffuse large B‐cell lymphomas: analysis of 231 Chinese patients

Genome instability is a hallmark of cancer. Diffuse large B‐cell lymphoma (DLBCL) is the most common form of non‐Hodgkin lymphoma with high levels of chromosomal aberrations. The purpose of this study was to characterize chromosomal aberrations in Chinese DLBCL patients and to compare chromosomal abnormalities between germinal centre B‐cell‐like (GCB) and non‐GCB subgroups. Fluorescence in situ hybridization, G‐band cytogenetics and immunohistochemistry were performed in 231 cases of de novo DLBCL. We demonstrated that the rate of abnormal and complex karyotypes was 89.1% (139/156) and 92.8% (129/139), respectively. We found a total of 490 structural chromosomal aberrations, including 96 frequent and recurring structural alterations. Most importantly, we identified several rare or novel chromosomal alterations: eight gains (5, 13, 14q, 17, 19p, 20, 21p, Y), one loss (21) and three recurrent translocations [t(7;15)(q22;q22), t(3;20)(p24;q13.1), t(2;3)(q21;q25)]. Moreover, the frequent recurrent genomic imbalance between GCB and non‐GCB subgroups was different. Finally, we discovered two cases of concurrent IGH‐BCL6 and MYC rearrangements. The rate of abnormal karyotypes in DLBCL patients of Chinese descent was similar to that of Western countries, but some common karyotypes were different, as were the abnormal karyotypes of GCB and non‐GCB subgroups. Our discovery of rare and novel abnormal karyotypes may represent unique chromosomal alterations in Chinese DLBCL patients. Copyright © 2012 John Wiley & Sons, Ltd.     

Characterization of genomic imbalances in diffuse large B‐cell lymphoma by detailed SNP‐chip analysis

The pathogenesis of diffuse large B‐cell lymphomas (DLBCL) is only partly understood. We analyzed 148 DLBCL by single nucleotide polymorphism (SNP)‐chips to characterize genomic imbalances. Seventy‐nine cases were of the germinal center B‐cell like (GCB) type of DLBCL, 49 of the activated B‐cell like (ABC) subtype and 20 were unclassified DLBCL. Twenty‐four regions of recurrent genomic gains and 38 regions of recurrent genomic losses were identified over the whole cohort, with a median of 25 imbalances per case for ABC‐DLBCL and 19 per case for GCB‐DLBCL. Several recurrent copy number changes showed differential frequencies in the GCB‐ and ABC‐DLBCL subgroups, including gains of HDAC7A predominantly in GCB‐DLBCL (38% of cases) and losses of BACH2 and CASP8AP2 predominantly in ABC‐DLBCL (35%), hinting at disparate pathogenetic mechanisms in these entities. Correlating gene expression and copy number revealed a strong gene dosage effect in all tumors, with 34% of probesets showing a concordant expression change in affected regions. Two new potential tumor suppressor genes emerging from the analysis, CASP3 and IL5RA, were sequenced in ten and 16 candidate cases, respectively. However, no mutations were found, pointing to a potential haploinsufficiency effect of these genes, considering their reduced expression in cases with deletions. Our study thus describes differences and similarities in the landscape of genomic aberrations in the DLBCL subgroups in a large collection of cases, confirming already known targets, but also discovering novel copy number changes with possible pathogenetic relevance.     

Chromosome instability in diffuse large B cell lymphomas is suppressed by activation of the noncanonical NF‐κB pathway

Diffuse large B cell lymphoma (DLBCL) is the most common form of lymphoma in the United States. DLBCL comprises biologically distinct subtypes including germinal center‐like (GCB) and activated‐B‐cell‐like DLBCL (ABC). The most aggressive type, ABC‐DLBCL, displays dysregulation of both canonical and noncanonical NF‐κB pathway as well as genomic instability. Although, much is known about the tumorigenic roles of the canonical NF‐kB pathway, the precise role of the noncanonical NF‐kB pathway remains unknown. Here we show that activation of the noncanonical NF‐κB pathway regulates chromosome stability, DNA damage response and centrosome duplication in DLBCL. Analysis of 92 DLBCL samples revealed that activation of the noncanonical NF‐κB pathway is associated with low levels of DNA damage and centrosome amplification. Inhibiting the noncanonical pathway in lymphoma cells uncovered baseline DNA damage and prevented doxorubicin‐induced DNA damage repair. In addition, it triggered centrosome amplification and chromosome instability, indicated by anaphase bridges, multipolar spindles and chromosome missegregation. We determined that the noncanonical NF‐κB pathway execute these functions through the regulation of GADD45α and REDD1 in a p53‐independent manner, while it collaborates with p53 to regulate cyclin G2 expression. Furthermore, this pathway regulates GADD45α, REDD1 and cyclin G2 through direct binding of NF‐κB sites to their promoter region. Overall, these results indicate that the noncanonical NF‐κB pathway plays a central role in maintaining genome integrity in DLBCL. Our data suggests that inhibition of the noncanonical NF‐kB pathway should be considered as an important component in DLBCL therapeutic approach.     

The GCB subtype of diffuse large B-cell lymphoma is less frequent in Asian countries

Patients with the germinal center B-cell-like (GCB) subtype of diffuse large B-cell lymphoma (DLBCL) have a significantly better survival rate than those with non-GCB DLBCL. Several studies have examined the proportions of GCB and non-GCB subtypes in large series of DLBCL patients, but it remains unclear if these proportions are the same in different countries. We performed an immunohistochemical analysis of the numbers of GCB and non-GCB subtypes in a large number of patients with DLBCL in Japan and compared the results with literature data for other countries. We found that 71 of 248 patients (29%) had the GCB phenotype and 177 patients (71%) had the non-GCB subtype of DLBCL among our patient population. Assessment of data collected from other studies showed that 31% of DLBCL patients (102/330) have the GCB subtype in Asian countries, but 50% (206/416) express GCB phenotypes in Western countries; based on these data, the occurrence of the GCB subtype of DLBCL was significantly less in Asian countries (p<0.001). Since patients with the GCB phenotype of DLBCL have better survival, future studies of DLBCL should recognize the difference in the proportions of GCB and non-GCB subtypes of DLBCL between Asian and Western populations.     

Survivin expression in patients with newly diagnosed nodal diffuse large B cell lymphoma (DLBCL)

Survivin is one of the inhibitors of apoptosis proteins (IAP) that might play an important role in the pathogenesis of diffuse large B cell lymphoma (DLBCL). The present study was designed to investigate the clinical and prognostic significance of survivin expression in nodal DLBCL. We analyzed lymph node biopsy specimens obtained from 56 patients with newly diagnosed nodal DLBCL, treated with immunochemotherapy (R-CHOP). The expression of survivin was analyzed using the standard immunohistochemical method on formalin-fixed and routinely processed paraffin-embedded lymph node specimens and evaluated semiquantitatively as a percentage of tumor cells. Survivin immunoexpression (>45?% positive tumor cells) was found in 22 (39.28?%) and observed as cytoplasmic staining in 15 patients, or mixed (cytoplasmic and nuclear) staining in 7 patients. A significant difference in survivin immunoexpression was noticed between the GCB and the non-GCB subtypes of DLBCL (p?=?0.031). However, survivin immunoexpression had no significant association with IPI, ??bulky?? disease, extranodal localization, hemoglobin, Ki-67 immunoexpression or other clinicopathological parameters. A univariate analysis showed that survivin positivity was an unfavorable factor for therapy response and a predictor of shorter survival in patients with DLBCL (p?=?0.048 and p?=?0.034, respectively). Patients with survivin overexpression experienced a relapse more often than patients without expression of this apoptotic protein (27.3 vs. 11.8?%), but this difference did not reach statistical significance (p?=?0.131). The results of this study showed that disregulation of survivin expression had an important role in the determination of the course of the disease in patients with nodal DLBCL treated with R-CHOP. Therefore, survivin represents a potential target for therapeutic intervention in DLBCL.     

Multicentre phase II study of CyclOBEAP plus rituximab in patients with diffuse large B‐cell lymphoma

The R‐CHOP regimen has been found to improve the outcome of diffuse large B‐cell lymphoma (DLBCL). However, it does not provide a satisfactory treatment outcome in the high‐risk group. We previously administered the CyclOBEAP regimen to patients with DLBCL, and reported its safety and efficacy. The R‐CyclOBEAP regimen was administered over a total period of 12 weeks, and rituximab 375 mg/m² was given every 2 weeks. There were 101 eligible patients. CR was achieved in 96 patients (95%). The 5‐year overall survival (OS) rate was 85% and progression‐free survival (PFS) rate was 76%. When the patients were divided according to the IPI, the 5‐year OS and PFS rates did not significantly differ among the risk groups. The 5‐year PFS of the germinal centre B‐cell group was 80% and that of the non‐GCB group was 74% (NS). Univariate analysis showed that the presence of B symptoms, extranodal lesions ≧2, and sIL‐2R were significant poor prognostic factors. Grade 4 neutropenia was observed in 91 patients and thrombocytopenia in 9 patients. The addition of rituximab to CyclOBEAP therapy may enhance the effect of CyclOBEAP therapy for DLBCL. Copyright © 2010 John Wiley & Sons, Ltd.     

Gene expression profiling of primary vitreoretinal lymphoma

The characteristics of tumor cells of primary vitreoretinal lymphoma (PVRL) have not been defined, although researches have shown that most cases are of diffuse large B‐cell lymphoma (DLBCL). To determine the subtype and biological characteristics of tumor cells of PVRL, we performed a gene expression profiling analysis. RNA was extracted from the vitreous fluid of 7 PVRL patients and from nodal samples of 10 DLBCL patients: 6 of germinal center B‐cell (GCB) type and 4 of activated B‐cell (ABC) type determined by Hans’ criteria. Six PVRL samples showed gene expression profiles that were similar to each other. The patterns were different from those of the ABC‐type nodular DLBCL but relatively close to those of the GCB‐type nodular DLBCL. Interestingly, all of the 6 examined PVRL samples had either MYD88^L265P or mutation in the immunoreceptor tyrosine‐based activation motif (ITAM) region of CD79B. Five PVRL patients with similar gene expression profiles were treated with a standardized regimen: intravitreal administration of methotrexate (MTX) followed by six courses of systemic high doses of MTX. As a result, 2 patients had CD79B mutations and showed early central nervous system (CNS) progression. Patients without CNS progression did not have this mutation. In conclusion, PVRL had unique genetic features: an expression pattern different from ABC‐type and relatively close to GCB‐type DLBCL. CD79B mutations showed potential to serve as prognostic markers for CNS progression.     

Higher response to lenalidomide in relapsed/refractory diffuse large B-cell lymphoma in nongerminal center B-cell-like than in germinal center B-cell-like phenotype

BACKGROUND:

There is a need to develop novel therapies for relapsed/refractory diffuse large B‐cell lymphoma (DLBCL) and to identify biomarkers predictive for therapeutic response. Lenalidomide was previously shown to induce an overall response rate (ORR) of 28% in patients with relapsed/refractory DLBCL. It is currently unknown if response rates differ between patients with different DLBCL subtypes.

METHODS:

The authors retrospectively evaluated clinical outcomes of patients with germinal center B‐cell–like versus nongerminal center B‐cell–like DLBCL treated with salvage lenalidomide at 4 academic institutions.

RESULTS:

Forty patients with relapsed/refractory DLBCL were included (24 men; 16 women; median age, 66 years; median of 4 prior treatments, including rituximab chemotherapy). Patients were classified as germinal center B‐cell–like (n = 23) or nongerminal center B‐cell–like (n = 17) DLBCL according to the Hans algorithm. The subgroups were similar in terms of stage, international prognostic index score, prior number of treatments, and rituximab resistance. A significant difference in clinical response to lenalidomide was observed in nongerminal center B‐cell–like versus germinal center B‐cell–like patients. ORR was 52.9% versus 8.7% (P = .006); complete response rate was 23.5% versus 4.3%. Median progression‐free survival was 6.2 versus 1.7 months (P = .004), although no difference in OS was observed between nongerminal center B‐cell–like and germinal center B‐cell–like DLBCL patients.

CONCLUSIONS:

The data suggest that the 2 major subgroups of patients with DLBCL (germinal center B cell and nongerminal center B cell) have different antitumor responsiveness to lenalidomide in the relapsed/refractory setting. A large international trial (NCT01197560) has been opened to enrollment in an attempt to prospectively validate these retrospective observations. Cancer 2011;. © 2011 American Cancer Society.     

Concurrent inhibition of PI3-Kinase and mTOR induces cell death in diffuse large B cell lymphomas,a mechanism involving down regulation of Mcl-1

Phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling is frequently dysregulated in diffuse large B cell lymphoma (DLBCL) including the favorable germinal centre B-cell (GCB) and the unfavorable activated B-cell (ABC) subtypes. mTOR promotes cap-dependent translation of proteins, like Mcl-1, through inhibitory phosphorylation of the eukaryotic translation initiation factor 4E binding protein 1 (4EBP1). Inhibition of mTOR by RAD001 reduces proliferation but fails to dephosphorylate 4EBP1 and to induce cell death in either DLBCL subtype. In contrast, concurrent inhibition of PI3K and mTOR with NVP-BEZ235 inhibits proliferation, dephosphorylates 4EBP1, and induces cells death, notably more pronounced in CGB cells. Small RNA interference identifies Mcl-1 as a crucial cell death mediator of both DLBCL subtypes. Inhibition of the PI3K/mTOR/4EBP1 by NVP-BEZ235 results in suppression of the cap-dependent translation initiation complex and concomitant downregulation of Mcl-1 in GCB cell lines. In ABC cell lines, this suppression is possibly compensated by NF-κB- or Pim kinase-mediated signaling.     

Clinical significance and prognosis of MYC translocation in diffuse large B-cell lymphoma

Recent studies have suggested that chromosomal aberrations of the MYC gene locus indicate an unfavorable prognosis in diffuse large B‐cell lymphoma (DLBCL). However, there have been few reports on MYC translocation in Chinese patients. One hundred and six cases of DLBCLs were analyzed using interphase fluorescent in situ hybridization. Immunophenotyping analysis (CD20, CD3, CD10, Bcl‐6, Mum‐1) was also performed. MYC translocation was identified in 13 (12.3%) out of 106 cases. All MYC⁺ DLBCLs showed a non‐germinal center B‐cell type. MYC⁺ DLBCLs showed significantly poorer overall survival (OS) and progression‐free survival, with a median OS and progression‐free survival time of 4.7 and 3.2 months, respectively (p < 0.001). Multivariate analysis using a Cox proportional hazard model confirmed that MYC⁺ (for OS, Hazards ratio 5.254; 95% CI, 2.354–11.723, p < 0.001) was the strongest independent predictor. DLBCL with MYC translocation is a subgroup of non‐germinal center B‐cell DLBCL with poor outcome. This may be a clinical characteristic that is specific to Chinese patients. Because only a few patients received rituximab, its usefulness could not be assessed. Future studies with larger numbers of patients are required. Copyright © 2011 John Wiley & Sons, Ltd.     

BCL2 mutations in diffuse large B-cell lymphoma

BCL2 is deregulated in diffuse large B-cell lymphoma (DLBCL) by the t(14;18) translocation, gene amplification and/or nuclear factor-κB signaling. RNA-seq data have recently shown that BCL2 is the most highly mutated gene in germinal center B-cell (GCB) DLBCL. We have sequenced BCL2 in 298 primary DLBCL biopsies, 131 additional non-Hodgkin lymphoma biopsies, 24 DLBCL cell lines and 51 germline DNAs. We found frequent BCL2 mutations in follicular lymphoma (FL) and GCB DLBCL, but low levels of BCL2 mutations in activated B-cell DLBCL, mantle cell lymphoma, small lymphocytic leukemia and peripheral T-cell lymphoma. We found no BCL2 mutations in GC centroblasts. Many mutations were non-synonymous; they were preferentially located in the flexible loop domain, with few in BCL2-homology domains. An elevated transition/transversions ratio supports that the mutations result from somatic hypermutation. BCL2 translocations correlate with, and are likely important in acquisition of, additional BCL2 mutations in GCB DLBCL and FL. DLBCL mutations were not independently associated with survival. Although previous studies of BCL2 mutations in FL have reported mutations to result in pseudo-negative BCL2 protein expression, we find this rare in de-novo DLBCL.     

MicroRNA expression distinguishes between germinal center B cell-like and activated B cell-like subtypes of diffuse large B cell lymphoma

Diffuse large B cell lymphoma (DLBCL) is an aggressive malignancy that accounts for nearly 40% of all lymphoid tumors. This heterogeneous disease can be divided into germinal center B cell-like (GCB) and activated B cell-like (ABC) subtypes by gene expression and immunohistochemical profiling. Using microarray analysis on prototypic cell lines, we identified microRNAs (miR-155, miR-21 and miR-221) that were more highly expressed in ABC-type than GCB-type cell lines. These microRNAs were over-expressed in de novo DLBCL (n = 35), transformed DLBCL (n = 14) and follicular center lymphoma cases (n = 27) compared to normal B cells. Consistent with the cell line model, expression levels were higher in DLBCL cases with an ABC-type immunophenotype than those that were GCB-type (p < 0.05). Moreover, using multivariate analysis we found that expression of miR-21 was an independent prognostic indicator in de novo DLBCL (p < 0.05). Interestingly, expression levels of both miR-155 and miR-21 were also higher in nonmalignant ABC than in GCB cells. As we also demonstrate that expression of microRNAs can be measured reliably from routine paraffin-embedded biopsies of more than 8-years-old (p < 0.001), we suggest that microRNAs could be clinically useful molecular markers for DLBCL as well as other cancers.     

Beta‐2 microglobulin as a significant prognostic factor and a new risk model for patients with diffuse large B‐cell lymphoma

Previous reports have evaluated the prognostic value of serum beta‐2 microglobulin (B2MG) level in patients with non‐Hodgkin lymphoma. However, its role in predicting clinical outcome of patients with diffuse large B‐cell lymphoma (DLBCL) in the rituximab era has not been extensively investigated. Here, we evaluated the prognostic value of B2MG and proposed a new prognostic model including B2MG for patients with DLBCL. A total of 274 patients with newly diagnosed de novo DLBCL were retrospectively analyzed. We defined the best cutoff value as 3.2 mg/L by using a receiver operating characteristic curve. Patients with a B2MG level ≥3.2 mg/L had significantly lower overall survival (OS) and progression‐free survival than those with a B2MG level <3.2 mg/L (3‐year OS, 50.9% vs. 89.4%, p < 0.001; 3‐year progression‐free survival, 45.3% vs. 79.7%, p < 0.001). Multivariate analysis showed that B2MG, age, performance status, and Ann Arbor stage were independent prognostic factors for OS. We developed a new prognostic model consisting of these four significant factors. We stratified patients into four‐risk groups: low (L, 0 factor), low‐intermediate (LI, 1–2 factors), high‐intermediate (HI, 3 factors), high (H, 4 factors). This new prognostic model showed better risk discrimination compared with the National Comprehensive Cancer Network‐International Prognostic Index (5‐year OS: 100% and 23.4% vs. 100% and 27.1%, in L and H risk groups, respectively). Our study suggested that B2MG level is a significant prognostic factor in patients with DLBCL. A new prognostic index composed of age, performance status, stage, and B2MG could stratify the outcomes of patients with DLBCL effectively and appears to be a valuable risk model for these patients. Copyright © 2016 John Wiley & Sons, Ltd.     

Frequent downregulation of BTB and CNC homology 2 expression in Epstein–Barr virus‐positive diffuse large B‐cell lymphoma

Diffuse large B‐cell lymphoma (DLBCL) is the most common B‐cell lymphoma subtype, and the Epstein–Barr virus (EBV)‐positive subtype of DLBCL is known to show a more aggressive clinical behavior than the EBV‐negative one. BTB and CNC homology 2 (BACH2) has been highlighted as a tumor suppressor in hematopoietic malignancies; however, the role of BACH2 in EBV‐positive DLBCL is unclear. In the present study, BACH2 expression and its significance were studied in 23 EBV‐positive and 43 EBV‐negative patient samples. Immunohistochemistry revealed BACH2 downregulation in EBV‐positive cases (P < 0.0001), although biallelic deletion of BACH2 was not detected by FISH. Next, we analyzed the contribution of BACH2 negativity to aggressiveness in EBV‐positive B‐cell lymphomas using FL‐18 (EBV‐negative) and FL‐18‐EB cells (FL‐18 sister cell line, EBV‐positive). In BACH2‐transfected FL‐18‐EB cells, downregulation of phosphorylated transforming growth factor‐β‐activated kinase 1 (pTAK1) and suppression in p65 nuclear fractions were observed by Western blot analysis contrary to non‐transfected FL‐18‐EB cells. In patient samples, pTAK1 expression and significant nuclear p65, p50, and p52 localization were detected immunohistochemically in BACH2‐negative DLBCL (P < 0.0001, P = 0.006, and P = 0.001, respectively), suggesting that BACH2 downregulation contributes to constitutive activation of the nuclear factor‐κB pathway through TAK1 phosphorylation in BACH2‐negative DLBCL (most EBV‐positive cases). Although further molecular and pathological studies are warranted to clarify the detailed mechanisms, downregulation of BACH2 may contribute to constitutive activation of the nuclear factor‐κB pathway through TAK1 activation.     

Clinicopathologic evaluation of subgroups of diffuse large B cell lymphoma by immunohistochemistry

Diffuse large B cell lymphoma (DLBCL) has become an emerging epidemic in recent years. Striking heterogeneity in its clinical, biological and treatment responses prompted us to identify variation in our study group. The aim was to classify the DLBCL into prognosis-based subgroups according to the WHO classification and to evaluate their relation to clinical parameters (age, gender, anatomic location and B symptoms), as well as bcl 2 and Ki 67 status. Patients and Methods: A cross sectional study was carried out on 42 DLBCL patients, classified histologically and immunophenotypically into germinal center B cell like (GCB) or non-GCB type. Immunohistochemistry (IHC) was performed using antibodies against CD 10, MUM-1 and bcl 6; additionally anti-apoptotic protein bcl 2 and proliferative marker Ki 67 (using cutoff value of 70%) were also assayed by IHC. Results: Of the total 27/42 (64%) were males and 15/42 (36%) females, with a mean age of 44.1±15 years. 15/42 (36%) cases were of GCB type as compared to 27/42 (64%) of non GCB type. Extranodal involvement and B symptoms were seen in 18/27 (66.6%) and 20/27(74%) of the non GCB type, whereas bcl 2 protein expression and Ki 67 proliferative index (PI) <70% were each noted in 22/27 (81.4%). Conclusion: We document an astonishingly high number of non-GCB type DLBCL in our population. It is alarming to see such an aggressive tumor proliferating in our region. Significant association of non-GCB type with extranodal origin, B symptoms and low Ki 67 PI (<70%) is another concern.     

miR-320d与弥漫大B细胞淋巴瘤预后的相关性研究

目的 探讨miR-320d表达与弥漫大B细胞淋巴瘤（DLBCL）预后的关系.方法 应用EnVision法对山西省肿瘤医院有随访资料的原发于淋巴结的DLBCL 62例石蜡标本进行CD20、CD3、CD10、bcl-6、Mum-1免疫标记检测,根据Hans分类方法将DLBCL分为生发中心B细胞（GCB）型和非生发中心B细胞（non-GCB）型.采用安捷伦16.0高密度芯片对24例DLBCL石蜡标本进行miRNA表达谱筛选,用实时荧光定量PCR方法对62例DLBCL石蜡标本进行miR-320d表达验证.将1 1例淋巴结反应性增生标本作为对照.结果 62例DLBCL中,GCB型22例（35.5％）,non-GCB型40例（64.5％）,GCB型miR-320d表达水平是non-GCB型的3.43倍（P=0.034）.miR-320d在对照组的表达量是DLBCL的5.65倍（P＜ 0.001）.单因素分析示DLBCL中miR-320d低表达组总生存期低于高表达组,差异有统计学意义（P=0.021）.多因素Cox回归模型分析示62例DLBCL中,miR-320d低表达（RR=2.434,95％CI1.148～5.159,P=0.020）为独立于国际预后指数（IPI）的预后不良因素.结论 miR-320d表达下调预示DLBCL预后不良.