Genomic and transcriptomic profiling of peripheral T cell lymphoma reveals distinct molecular and microenvironment subtypes.

Peripheral T cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin's lymphomas varying in clinical, phenotypic, and genetic features. The molecular pathogenesis and the role of the tumor microenvironment in PTCL are poorly understood, with limited biomarkers available for genetic subtyping and targeted therapies. Through an integrated genomic and transcriptomic study of 221 PTCL patients, we delineate the genetic landscape of PTCL, enabling molecular and microenvironment classification. According to the mutational status of RHOA, TET2, histone-modifying, and immune-related genes, PTCL is divided into 4 molecular subtypes with discrete patterns of gene expression, biological aberrations, and vulnerabilities to targeted agents. We also perform an unsupervised clustering on the microenvironment transcriptional signatures and categorize PTCL into 4 lymphoma microenvironment subtypes based on characteristic activation of oncogenic pathways and composition of immune communities. Our findings highlight the potential clinical rationale of future precision medicine strategies that target both molecular and microenvironment alterations in PTCL.

The non-cell-autonomous function of ID1 promotes AML progression via ANGPTL7 from the microenvironment.

The bone marrow microenvironment (BMM) can regulate leukemia stem cells (LSCs) via secreted factors. Increasing evidence suggests that dissecting the mechanisms by which the BMM maintains LSCs may lead to the development of effective therapies for the eradication of leukemia. Inhibitor of DNA binding 1 (ID1), a key transcriptional regulator in LSCs, previously identified by us, controls cytokine production in the BMM, but the role of ID1 in acute myeloid leukemia (AML) BMM remains obscure. Here, we report that ID1 is highly expressed in the BMM of patients with AML, especially in BM mesenchymal stem cells, and that the high expression of ID1 in the AML BMM is induced by BMP6, secreted from AML cells. Knocking out ID1 in mesenchymal cells significantly suppresses the proliferation of cocultured AML cells. Loss of Id1 in the BMM results in impaired AML progression in AML mouse models. Mechanistically, we found that Id1 deficiency significantly reduces SP1 protein levels in mesenchymal cells cocultured with AML cells. Using ID1-interactome analysis, we found that ID1 interacts with RNF4, an E3 ubiquitin ligase, and causes a decrease in SP1 ubiquitination. Disrupting the ID1-RNF4 interaction via truncation in mesenchymal cells significantly reduces SP1 protein levels and delays AML cell proliferation. We identify that the target of Sp1, Angptl7, is the primary differentially expression protein factor in Id1-deficient BM supernatant fluid to regulate AML progression in mice. Our study highlights the critical role of ID1 in the AML BMM and aids the development of therapeutic strategies for AML.

Inhibition of USP1 reverses the chemotherapy resistance through destabilization of MAX in the relapsed/refractory B-cell lymphoma.

The patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) have poor prognosis, and a novel and effective therapeutic strategy for these patients is urgently needed. Although ubiquitin-specific protease 1 (USP1) plays a key role in cancer, the carcinogenic effect of USP1 in B-cell lymphoma remains elusive. Here we found that USP1 is highly expressed in DLBCL patients, and high expression of USP1 predicts poor prognosis. Knocking down USP1 or a specific inhibitor of USP1, pimozide, induced cell growth inhibition, cell cycle arrest and autophagy in DLBCL cells. Targeting USP1 by shRNA or pimozide significantly reduced tumor burden of a mouse model established with engraftment of rituximab/chemotherapy resistant DLBCL cells. Pimozide significantly retarded the growth of lymphoma in a DLBCL patient-derived xenograft (PDX) model. USP1 directly interacted with MAX, a MYC binding protein, and maintained the stability of MAX through deubiquitination, which promoted the transcription of MYC target genes. Moreover, pimozide showed a synergetic effect with etoposide, a chemotherapy drug, in cell and mouse models of rituximab/chemotherapy resistant DLBCL. Our study highlights the critical role of USP1 in the rituximab/chemotherapy resistance of DLBCL through deubiquitylating MAX, and provides a novel therapeutic strategy for rituximab/chemotherapy resistant DLBCL.

Clinicopathologic features and abnormal signaling pathways in plasmablastic lymphoma: a multicenter study in China.

BACKGROUND: Plasmablastic lymphoma (PBL) is a rare but aggressive B-cell lymphoma subtype with poor prognosis. Knowledge about the etiology, clinicopathologic and molecular features, and outcomes of PBL is limited. This study aimed to examine the clinicopathologic characteristics, therapeutic approaches, and clinical outcomes of PBL patients in a Chinese population. METHODS: A total of 102 PBL patients were recruited from three cancer centers. The pathologic features and clinical outcomes of 56 patients with available treatment details and follow-up data were reviewed and analyzed. RNA sequencing was performed in 6 PBL and 11 diffuse large B-cell lymphoma (DLBCL) patients. RESULTS: Most patients in our cohort were male (n = 36, 64.3%), and 35 patients presented with Ann Arbor stage I/II disease at diagnosis. All these patients showed negative findings for human immunodeficiency virus, and the vast majority of patients in our cohort were immunocompetent. Lymph nodes (n = 13, 23.2%) and gastrointestinal tract (n = 10, 17.9%) were the most commonly involved site at presentation. Post-treatment complete remission (CR) was the only prognostic factor affecting overall survival (OS) and progression-free survival (PFS) in the multivariate analysis. RNA-seq demonstrated that B-cell receptor (BCR), T-cell receptor (TCR), P53, calcium signaling, and Wnt signaling pathways were significantly downregulated in PBLs compared with GCB (or non-GCB) DLBCLs. CONCLUSIONS: In this multicenter study in the Chinese population, PBL mainly occurred in immunocompetent individuals and most patients present with early-stage disease at diagnosis. Post-treatment CR was an important prognostic factor affecting OS and PFS. RNA-seq showed that the B-cell receptor (BCR), P53, calcium signaling, cell adhesion molecules, and Wnt signaling pathways significantly differed between PBL and GCB (or non-GCB) DLBCL, which provided theoretical basis for its pathogenesis and future treatment.

Transcriptome-wide subtyping of pediatric and adult T cell acute lymphoblastic leukemia in an international study of 707 cases.

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy of T cell progenitors, known to be a heterogeneous disease in pediatric and adult patients. Here we attempted to better understand the disease at the molecular level based on the transcriptomic landscape of 707 T-ALL patients (510 pediatric, 190 adult patients, and 7 with unknown age; 599 from published cohorts and 108 newly investigated). Leveraging the information of gene expression enabled us to identify 10 subtypes (G1­G10), including the previously undescribed one characterized by GATA3 mutations, with GATA3R276Q capable of affecting lymphocyte development in zebrafish. Through associating with T cell differentiation stages, we found that high expression of LYL1/LMO2/SPI1/HOXA (G1­G6) might represent the early T cell progenitor, pro/precortical/cortical stage with a relatively high age of disease onset, and lymphoblasts with TLX3/TLX1 high expression (G7­G8) could be blocked at the cortical/postcortical stage, while those with high expression of NKX2-1/TAL1/LMO1 (G9­G10) might correspond to cortical/postcortical/mature stages of T cell development. Notably, adult patients harbored more cooperative mutations among epigenetic regulators, and genes involved in JAK-STAT and RAS signaling pathways, with 44% of patients aged 40 y or above in G1 bearing DNMT3A/IDH2 mutations usually seen in acute myeloid leukemia, suggesting the nature of mixed phenotype acute leukemia.

Universal extracellular vesicles and PD-L1+ extracellular vesicles detected by single molecule array technology as circulating biomarkers for diffuse large B cell lymphoma.

Plasma extracellular vesicles (EVs) have been reported to be a promising source of diagnostic and prognostic biomarkers in various cancers. However, further research in this area is needed due to the limitations of circulating extracellular vesicles detection methods. Using the Single Molecule array (SiMoa) technology, we developed two extracellular vesicle detection assays, CD9-CD63 and PD-L1-CD63, to determine circulating universal EVs and PD-L1 positive EVs, respectively. A total of 164 diffuse large B-cell lymphoma (DLBCL) patients were retrospectively included in this study. Compared with healthy volunteers (n = 25), elevated CD9-CD63 and PD-L1-CD63 signals were detected in the plasma of DLBCL patients (n = 164). High CD9-CD63 signals was associated with molecular subtype, extranodal site and treatment response in DLBCL. A high PD-L1-CD63 signal was also associated with certain clinical features, including extranodal site and treatment response. CD9-CD63 and PD-L1-CD63 signals were found to be important prognostic factors for both progression-free and overall survival. Furthermore, PD-L1-positive EVs were found in all patients, though PD-L1 protein expression was positive in only 35.4% (17/48) of tumor biopsies. No correlation was found between circulating PD-L1+ EVs and soluble PD-L1 (sPD-L1) levels. Our results show that plasma universal EV and PD-L1-positive EV levels are significantly elevated in DLBCL and might serve as biomarkers for predicting survival outcomes in DLBCL patients.

Chidamide triggers BTG1-mediated autophagy and reverses the chemotherapy resistance in the relapsed/refractory B-cell lymphoma.

Rituximab/chemotherapy relapsed and refractory B cell lymphoma patients have a poor overall prognosis, and it is urgent to develop novel drugs for improving the therapy outcomes. Here, we examined the therapeutic effects of chidamide, a new histone deacetylase (HDAC) inhibitor, on the cell and mouse models of rituximab/chemotherapy resistant B-cell lymphoma. In Raji-4RH/RL-4RH cells, the rituximab/chemotherapy resistant B-cell lymphoma cell lines (RRCL), chidamide treatment induced growth inhibition and G0/G1 cell cycle arrest. The primary B-cell lymphoma cells from Rituximab/chemotherapy relapsed patients were sensitive to chidamide. Interestingly, chidamide triggered the cell death with the activation of autophagy in RRCLs, likely due to the lack of the pro-apoptotic proteins. Based on the RNA-seq and chromatin immunoprecipitation (ChIP) analysis, we identified BTG1 and FOXO1 as chidamide target genes, which control the autophagy and the cell cycle, respectively. Moreover, the combination of chidamide with the chemotherapy drug cisplatin increased growth inhibition on the RRCL in a synergistic manner, and significantly reduced the tumor burden of a mouse lymphoma model established with engraftment of RRCL. Taken together, these results provide a theoretic and mechanistic basis for further evaluation of the chidamide-based treatment in rituximab/chemotherapy relapsed and refractory B-cell lymphoma patients.

Prognostic Significance of LDH Ratio in Serum/Cerebral Spinal Fluid of Patients with Primary Testicular Diffuse Large B-Cell Lymphoma.

OBJECTIVE: Primary testicular diffuse large B-cell lymphoma (PT-DLBCL) is relatively rare, and risk factors of this disease are still not well understood. This study aims to identify clinical features and prognostic factors of PT-DLBCL patients. METHODS: Thirty-two patients were included in this retrospective study who were diagnosed as PT-DLBCL and treated in Fudan University Shanghai Cancer Center between November 2010 and May 2018. The demographic details, clinico-pathological characteristics of the patients were summarized, and the impact on progression-free survival (PFS) and overall survival (OS) was analyzed. RESULTS: The median age of the patients was 57 (range 36-76) years old. All patients received rituximab in combination with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for 4-6 cycles and central nervous system (CNS) prophylaxis, with a CR rate 87.5% and an ORR 96.9%. Nineteen patients continued prophylactic contralateral testis radiation therapy (PCTRT) in our hospital. The 3-year PFS and OS rates were 79% and 92%, respectively. None of the 19 patients who received PCTRT experienced local recurrence. All three patients who suffered from CNS relapse were germinal center B-cell subtype. Kaplan-Meier analyses showed that PT-DLBCL patients with late-stage (Stage IV) (P =0.022), higher IPI score (IPI≥ 2) (P =0.017), B symptoms (P =0.004), and elevated LDH level (P =0.03) had a shorter PFS. More importantly, we found that patients with the ratio of the LDH level in serum to that in CSF ≥ 6.5 suffered from a worse PFS (P =0.028). CONCLUSION: Our work revealed that staging IV, IPI score ≥2, having B symptoms and elevated LDH level were risk factors for PT-DLBCL patients. Significantly, the PT-DLBCL patients with a high ratio of LDH level in serum to that in CSF were indicated to have a worse PFS.

The size and depth of lesions measured by endoscopic ultrasonography are novel prognostic factors of primary gastric diffuse large B-cell lymphoma.

Diffuse large B cell lymphoma is one of the predominant histological subtypes of primary gastric lymphomas. Factors that contribute to precise stratification and guide the treatment of this disease are still not well understood. We analyzed 73 primary gastric diffuse large B cell lymphoma patients retrospectively, and found that patients characterized by late stage, multiple localization, B symptoms, lower serum albumin level and elevated LDH level had a shorter overall survival through Univariate Cox regression analysis. Multivariate Cox regression analysis demonstrated that ALB ≤ 35g/L, staging ≥ IIE and multiple sites localization were independent adverse prognostic factors. Significantly, in 35 patients who received endoscopy at diagnosis, Kaplan-Meier analyses indicated that patients with large (≥3 cm) and deep lesions (≥11 mm) had an inferior OS (p = .01 and .039). These findings implicated that tumor size and depth are two indicators of prognosis under ultrasonography. Further randomized studies with large number of cases are needed.

Early anthracycline-induced cardiotoxicity monitored by echocardiographic Doppler parameters combined with serum hs-cTnT.

PURPOSE: As growing numbers of long-term cancer survivors faced with the cardiac side effects by anthracycline treatment, it is necessary to explore the optimal monitoring method for the early detection of cardiac toxicity. METHODS: We conducted a retrospective analysis of 82 consecutive patients with diffuse large B-cell lymphoma treated with chemotherapy. Echocardiographic Doppler imaging-derived Tei index and mitral annular peak systolic velocity (Sm) measured by tissue Doppler imaging TDI, serum high-sensitivity cardiac troponin T (hs-cTnT) levels, and left ventricular ejection fraction (LVEF) by multigated radionuclide angiography (MUGA) were obtained before, after 2-4, and after 6-8 chemotherapy cycles. Cardiotoxicity was defined as a relative reduction of LVEF ≥10% from the baseline or LVEF <50% as measured by MUGA. RESULTS: Following chemotherapy, 24 (29.3%) patients developed detectable cardiac abnormality during the treatment. Five (6.1%) patients' cardiac function changed from normal baseline LVEF to <50% after the chemotherapy. Echocardiographic pulse wave Doppler Tei index (PW Tei index) (baseline 0.347 ± 0.115 vs 2-4 cycles 0.459 ± 0.161 vs 6-8 cycles 0.424 ± 0.139, P = .000) inversely correlated with systolic (P < .001) and diastolic dysfunction (P < .001). Serum hs-cTnT levels increased significantly following chemotherapy after 2-4 cycles of chemotherapy with anthracycline. The increase in PW Tei index of 0.095 [sensitivity, 69.2%; specificity, 64.5%; area under the curve (AUC) = 0.697; P = .005] and the Sm < 13.65 cm/s (sensitivity, 66.7%; specificity, 71%; AUC = 0.682; P = .009) combined with elevation of serum hs-cTnT level of 0.0075 ng/mL (sensitivity, 69.2%; specificity, 83.9%; AUC = 0.790; P < .001) after 2-4 chemotherapy cycles from the baseline values can reliably predict cardiotoxicity. CONCLUSIONS: We demonstrated that echocardiographic PW Doppler-derived Tei index, and TDI-derived Sm, combined with serum hs-cTnT level can be obtained in outpatient settings to monitor early cardiac toxicity induced by anthracycline therapy.

Assessment of biventricular systolic strain derived from the two-dimensional and three-dimensional speckle tracking echocardiography in lymphoma patients after anthracycline therapy.

The aim of this study was to investigate the usefulness of three-dimensional (3D) speckle tracking echocardiography (STE) for assessment of both left and right ventricular systolic function in patients with lymphoma after anthracycline chemotherapy, compared with two-dimensional (2D) STE. Totally eighty-nine patients undergoing anthracycline containing chemotherapy were studied. Echocardiographic assessment included 2D and 3D left ventricular (LV) global longitudinal strain (GLS), global circumferential strain (GCS) and right ventricular (RV) GLS. All the parameters were analyzed at baseline, after the completion of four cycles and at the end of the regimen respectively. The area under the receiver operating characteristic curve was calculated to determine the capability of various echocardiographic parameters to discriminate between before and after chemotherapy. Compared with those at baseline, the 3D GLS and GCS of LV and GLS of RV decreased significantly after four cycles of the therapy (all p < 0.01). At the end of the treatment, 2D GLS and GCS of LV deteriorated markedly (both p < 0.05). The area under the curve for GLS, GCS of LV and GLS of RV derived by 3D were 0.81, 0.66 and 0.78, respectively. The cutoff value with -20.4% of LV GLS by 3D had sensitivity of 81% and specificity of 66% for differentiating patients after therapy from baselines. The cutoff value with -21.9% of RV GLS by 3D had sensitivity of 71% and specificity of 74% fordifferentiating patients after therapy from baselines. The data from this study demonstrated that both 2D and 3D STE can be conducted to evaluate the slight myocardial damage for lymphoma patients after anthracycline chemotherapy. 3D STE could examine subclinical biventricular dysfunction in earlier point than 2D STE.

Intermittent high dose proton pump inhibitor enhances the antitumor effects of chemotherapy in metastatic breast cancer.

BACKGROUND: Acidity is a hallmark of malignant tumor, representing a very efficient mechanism of chemoresistance. Proton pump inhibitors (PPI) at high dosage have been shown to sensitize chemoresistant human tumor cells and tumors to cytotoxic molecules. The aim of this pilot study was to investigate the efficacy of PPI in improving the clinical outcome of docetaxel + cisplatin regimen in patients with metastatic breast cancer (MBC). METHODS: Patients enrolled were randomly assigned to three arms: Arm A, docetaxel 75 mg/m(2) followed by cisplatin 75 mg/m(2) on d4, repeated every 21 days with a maximum of 6 cycles; Arm B, the same chemotherapy preceded by three days esomeprazole (ESOM) 80 mg p.o. bid, beginning on d1 repeated weekly. Weekly intermittent administration of ESOM (3 days on 4 days off) was maintained up to maximum 66 weeks; Arm C, the same as Arm B with the only difference being dose of ESOM at 100 mg p.o. bid. The primary endpoint was response rate. RESULTS: Ninety-four patients were randomly assigned and underwent at least one injection of chemotherapy. Response rates for arm A, B and C were 46.9, 71.0, and 64.5 %, respectively. Median TTP for arm A (n = 32), B (n = 31), C (n = 31) were 8.7, 9.4, and 9.7 months, respectively. A significant difference was observed between patients who had taken PPI and who not with ORR (67.7 % vs. 46.9 %, p = 0.049) and median TTP (9.7 months vs. 8.7 months, p = 0.045) [corrected]. Exploratory analysis showed that among 15 patients with triple negative breast cancer (TNBC), this difference was bigger with median TTP of 10.7 and 5.8 months, respectively (p = 0.011). PPI combination showed a marked effect on OS as well, while with a borderline significance (29.9 vs. 19.2 months, p = 0.090). No additional toxicity was observed with PPI. CONCLUSIONS: The results of this pilot clinical trial showed that intermittent high dose PPI enhance the antitumor effects of chemotherapy in MBC patients without evidence of additional toxicity, which requires urgent validation in a multicenter, randomized, phase III trial. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01069081 .

Eriocalyxin B ameliorates experimental autoimmune encephalomyelitis by suppressing Th1 and Th17 cells.

Eriocalyxin B (EriB), a diterpenoid isolated from Isodon eriocalyx, was previously reported to have antitumor effects via multiple pathways, and these pathways are related to immune responses. In this study, we demonstrated that EriB was efficacious in experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis. Treatment with EriB led to amelioration of EAE, which correlated with reduced spinal cord inflammation and demyelination. EriB treatment abolished encephalitogenic T-cell responses to myelin oligodendrocyte glycoprotein in an adoptive transfer EAE model. The underlying mechanism of EriB-induced effects involved inhibition of T helper (Th) 1 and Th17 cell differentiation through Janus Kinase/Signal Transducer and Activator Of Transcription and Nuclear factor-κB signaling pathways as well as elevation of reactive oxygen species. These findings indicate that EriB exerts potent antiinflammatory effects through selective modulation of pathogenic Th1 and Th17 cells by targeting critical signaling pathways. The study provides insights into the role of EriB as a unique therapeutic agent for the treatment of autoimmune diseases.

Phase II study of oxaliplatin plus leucovorin and 5-fluorouracil in heavily pretreated metastatic breast cancer patients.

The aim of this phase II study was to investigate the efficacy and safety of oxaliplatin plus 5-fluorouracil (5-FU) and leucovorin (LV) in metastatic breast cancer (MBC) patients heavily pretreated with anthracyclines, taxanes, vinorelbine, gemcitabine, and capecitabine. Sixty-two women who had received at least 3 above-mentioned drug classes were treated with oxaliplatin 85 mg/m(2) as a 2-h infusion on day 1, LV 200 mg/m(2) as a 2-h infusion followed by bolus 5-FU 400 mg/m(2) on day 1, and a continuous infusion of 5-FU 1,200 mg/m(2) for 44 h. The median patient age was 52 years with a median of two involved organs, and the metastases were mostly in the lung (53.2%), lymph nodes (51.6%), and liver (45.2%). Patients had a median of three prior chemotherapy regimens. Forty-five patients (72.6%) had prior exposure to all 5 classes of drugs. Based on an intention-to-treat analysis, 60 patients were assessable for responses and 11 patients achieved a partial response (PR), giving an overall response rate (ORR) of 18.3%. Twenty-one (35%) patients had stable disease (SD), and of these, 8 achieved long SD (13.3%). The median progression-free survival (PFS) was 3 months, and the median overall survival (OS) was 10 months. Toxicity was mild to moderate with grade 3 or 4 neutropenia, thrombocytopenia, and neuropathy occurring in 14 (22.6%), 9 (14.5%), and 3 (4.8%) patients, respectively. The study demonstrated that the combination of oxaliplatin plus 5-FU/LV was a well-tolerated salvage regimen with moderate activity in patients with heavily pretreated MBC.

Current evidences on vascular endothelial growth factor polymorphisms and breast cancer susceptibility.

Several polymorphisms of vascular endothelial growth factor (VEGF) such as 936 C/T, -2578 C/A, -406 C/T, and -1154 G/A polymorphism have been identified. Published data on the association between VEGF polymorphisms and breast cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Crude OR with 95% CI was used to assess the strength of association between them. For VEGF 936C/T polymorphism, a total of 10 studies including 7,685 cases and 7,915 controls were involved in this meta-analysis. Overall, no significant associations were found between VEGF 936C/T polymorphism and breast cancer risk when all studies pooled into the meta-analysis (TC vs. CC: OR = 0.904, 95% CI = 0.797-1.024; TT vs. CC: OR = 0.974, 95% CI = 0.786-1.205; dominant model: OR = 0.911, 95% CI = 0.811-1.024; and recessive model: OR = 0.991, 95% CI = 0.801-1.226). In the subgroup analysis by ethnicity, still no significant associations were found for all comparison models. For -2578 C/A, -406 C/T, and -1154 G/A polymorphism, there were too limited data to perform a meta-analysis. In conclusion, this meta-analysis suggests that the VEGF 936C/T polymorphism may be not associated with breast cancer development. However, large sample and representative population-based studies with homogeneous breast cancer patients and well matched controls are warranted to confirm this finding.

Lack of association between methylenetetrahydrofolate reductase gene A1298C polymorphism and breast cancer susceptibility.

Published data on the association between methylenetetrahydrofolate reductase gene (MTHFR) A1298C polymorphism and breast cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Medline, PubMed, Embase, and Web of Science were searched. Crude ORs with 95% CIs were used to assess the strength of association between the MTHFR A1298C polymorphism and breast cancer risk. The pooled ORs were performed for co-dominant model (AC vs. AA, CC vs. AA), dominant model (CC+AC vs. AA), and recessive model (CC vs. AC+AA), respectively. A total of 26 studies including 12,244 cases and 15,873 controls were involved in this meta-analysis. Overall, no significant associations were found between MTHFR A1298C polymorphism and breast cancer risk when all studies pooled into the meta-analysis (AC vs. AA: OR=0.99, 95% CI 0.94-1.05; CC vs. AA: OR 0.99, 95% CI 0.90-1.09; dominant model: OR=0.99, 95% CI 0.95-1.04; and recessive model: OR=0.98, 95% CI 0.90-1.08). In the subgroup analysis by ethnicity or study design, still no significant associations were found for all comparison models. In conclusion, this meta-analysis suggests that the MTHFR A1298C polymorphism may be not associated with breast cancer development. However, large sample and representative population-based studies with homogeneous breast cancer patients and well matched controls are warranted to confirm this finding.

[Synergistic effects of proteasome inhibitor and histone deacetylase inhibitor on apoptosis and aggresome formation in T lymphoma cells].

The aim of the study was to explore the synergistic effect of the proteasome inhibitor bortezomib (bor) and the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA) on apoptosis of T lymphoma cell lines Jurkat and Hut78, and on the formation of aggresome. Jurkat and Hut78 cells were treated with bor (10 nmol/L) or bor (10 nmol/L) combined with SAHA (2 micromol/L) respectively. Cell growth inhibition was estimated by trypan blue dye exclusion test. Cell morphology was evaluated by light microscopy with Wright's staining of cytocentrifuge preparations. Cell apoptosis was analyzed by flow cytometry. Ultrastructure of cell apoptosis and aggresome were observed by transmission electron microscopy. The results showed that proliferation of both Jurkat and Hut78 cells was significantly inhibited in the bor+SAHA group, as compared with the control group and the bor alone group. Flow cytometric analysis confirmed that the percentage of apoptosis in Jurkat and Hut78 cells in the bor+SAHA group (41.8+/-4.7% and 72.7+/-11.7% respectively) was remarkably higher than those in the control group (3.6+/-1.3% and 7.0+/-1.9% respectively) and the bor alone group (6.3+/-2.3% and 18.7+/-9.2% respectively) (p<0.01). Ultrastructure examination revealed that typical aggresomes in cells could be observed in bor alone group. The combination of bor and SAHA diminished both the amount and density of aggresomes, or even eliminated them, accompanied by the increased rate of apoptosis. It is concluded that proteasome inhibitor combined with histone deacetylase inhibitor synergically induces T lymphoma cell apoptosis. Bortezomib stimulates the formation of aggresome, while SAHA destroys this aggresome structure, which may be one of the mechanisms underlying the enhancement of bortezomib-induced apoptosis.

PRDM1 is involved in chemoresistance of T-cell lymphoma and down-regulated by the proteasome inhibitor.

The positive regulatory domain I (PRDM1) is a master regulator of terminal B-cell differentiation. However, PRDM1 is not B-cell specific. To determine its role in T-cell lymphoma, PRDM1 expression was investigated in 60 patients. PRDM1alpha and PRDM1beta transcripts were detected in laser-microdissected T-lymphoma cells in 27 and 14 patients, respectively, mostly in cases with IRF4 expression. PRDM1beta was associated with increased c-MYC expression. PRDM1beta-positive patients displayed advanced Ann Arbor stage and high-risk International Prognostic Index and were linked to short survival times. In vitro, PRDM1beta was related to resistance to chemotherapeutic agents and could be down-regulated by the proteasome inhibitor bortezomib. Kinetic studies showed that bortezomib down-regulation of PRDM1beta preceded decreased IRF4 and c-MYC expression. An earlier retaining of cytoplasmic IkappaBalpha in bortezomib-treated cells was revealed, concomitant with blockade of NF-kappaB nuclear translocation. These results demonstrate the involvement of PRDM1beta in T-cell lymphoma, with possible therapeutic interference by the proteasome inhibitor.