Bowel perforation in intestinal lymphoma: incidence and clinical features.

BACKGROUND: Perforation is a serious life-threatening complication of lymphomas involving the gastrointestinal (GI) tract. Although some perforations occur as the initial presentation of GI lymphoma, others occur after initiation of chemotherapy. To define the location and timing of perforation, a single-center study was carried out of all patients with GI lymphoma. PATIENTS AND METHODS: Between 1975 and 2012, 1062 patients were identified with biopsy-proven GI involvement with lymphoma. A retrospective chart review was undertaken to identify patients with gut perforation and to determine their clinicopathologic features. RESULTS: Nine percent (92 of 1062) of patients developed a perforation, of which 55% (51 of 92) occurred after chemotherapy. The median day of perforation after initiation of chemotherapy was 46 days (mean, 83 days; range, 2-298) and 44% of perforations occurred within the first 4 weeks of treatment. Diffuse large B-cell lymphoma (DLBCL) was the most common lymphoma associated with perforation (59%, 55 of 92). Compared with indolent B-cell lymphomas, the risk of perforation was higher with aggressive B-cell lymphomas (hazard ratio, HR = 6.31, P < 0.0001) or T-cell/other types (HR = 12.40, P < 0.0001). The small intestine was the most common site of perforation (59%). CONCLUSION: Perforation remains a significant complication of GI lymphomas and is more frequently associated with aggressive than indolent lymphomas. Supported in part by University of Iowa/Mayo Clinic SPORE CA97274 and the Predolin Foundation.

Report of consensus panel 7 from the 11th international workshop on Waldenström macroglobulinemia on priorities for novel clinical trials.

Recent advances in the understanding of Waldenström macroglobulinemia (WM) biology have impacted the development of effective novel agents and improved our knowledge of how the genomic background of WM may influence selection of therapy. Consensus Panel 7 (CP7) of the 11th International Workshop on WM was convened to examine the current generation of completed and ongoing clinical trials involving novel agents, consider updated data on WM genomics, and make recommendations on the design and prioritization of future clinical trials. CP7 considers limited duration and novel-novel agent combinations to be the priority for the next generation of clinical trials. Evaluation of MYD88, CXCR4 and TP53 at baseline in the context of clinical trials is crucial. The common chemoimmunotherapy backbones, bendamustine-rituximab (BR) and dexamethasone, rituximab and cyclophosphamide (DRC), may be considered standard-of-care for the frontline comparative studies. Key unanswered questions include the definition of frailty in WM; the importance of attaining a very good partial response or better (≥VGPR), within stipulated time frame, in determining survival outcomes; and the optimal treatment of WM populations with special needs.

A Phase 1b/2 trial of mapatumumab in patients with relapsed/refractory non-Hodgkin's lymphoma.

BACKGROUND: we conducted a multicentre Phase 1b/2 trial to evaluate the safety and efficacy of mapatumumab, a fully human agonistic monoclonal antibody to the tumour necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1) in patients with relapsed non-Hodgkin's lymphoma (NHL). METHODS: forty patients with relapsed or refractory NHL were treated with either 3 or 10 mg kg(-1) mapatumumab every 21 days. In the absence of disease progression or prohibitive toxicity, patients received a maximum of six doses. RESULTS: mapatumumab was well tolerated, with no patients experiencing drug-related hepatic or other dose-limiting toxicity. Three patients with follicular lymphoma (FL) experienced clinical responses, including two with a complete response and one with a partial response. Immunohistochemistry staining of the TRAIL-R1 suggested that strong staining in tumour specimens did not appear to be a requirement for mapatumumab activity in FL. CONCLUSIONS: mapatumumab is safe and has promising clinical activity in patients with FL.

Time of relapse after initial therapy significantly adds to the prognostic value of the IPI-R in patients with relapsed DLBCL undergoing autologous stem cell transplantation.

We explored the concomitant effect of the International Prognostic Index at the time of relapse (IPI-R) and the time from initial diagnosis to relapse (TTR) on outcome of 80 uniformly treated patients receiving BEAM conditioning followed by SCT for relapsed, chemosensitive diffuse large B-cell lymphoma. Median age at the time of transplantation was 62 years (range 26-77). Median follow-up of survivors was 31.4 months. Median overall survival (OS) from the time of transplant for patients with TTR >18 months vs < or =18 months was not reached and 50 months, respectively (P=0.01). Median OS for patients with IPI-R > or =3 was 23.3 months and not reached for patients with IPI-R <3 (P=0.01). These factors were independent in multivariate analysis with relative risk for death of 0.91 (0.80-0.99; P=0.04) for each 6-month increment in TTR and 0.63 (0.42-0.96; P=0.03) for IPI-R <3. TTR < or =18 months and IPI-R > or =3 were combined in a prognostic system where patients with none (n=32), one (n=39) or two (n=9) of these factors had median OS not reached, of 50 and 5 months, respectively (P<0.01). Patients with early, high IPI-R relapse after first-line therapy have a dismal outcome with SCT and should receive experimental therapies.

Infusion of autograft natural killer cell/CD14+HLA-DRDIM cell ratio predicts survival in lymphoma post autologous stem cell transplantation.

The infusion of autograft absolute lymphocyte count (A-ALC) and autograft natural killer cells (A-NKC) are prognostic factors for overall survival (OS) and PFS in non-Hodgkin's lymphoma (NHL) patients undergoing autologous peripheral blood hematopoietic stem cell transplantation (APBHSCT). The human monocytic CD14+HLA-DRDIM cells are associated with worse prognosis in NHL. Thus, we investigated whether the autograft A-NKC/A-CD14+HLA-DRDIM ratio predicts survival in NHL. In a total of 111 NHL patients, we analyzed apheresis collection samples for the content of A-NKC and A-CD14+HLA-DRDIM. With a median follow-up of 57.2 months (range: 2.1-84.6 months), patients with an A-NKC/A-CD14+HLA-DRDIM ratio of ⩾0.29 experienced superior OS (5-year OS rates of 84% (95% confidence interval (CI), 72-91%) vs 48% (95% CI, 34-62%), P<0.0002, respectively) and PFS (5-year PFS rates of 59% (95% CI, 47-71%) vs 32% (95% CI, 20-48%), P<0.002, respectively). Multivariate analysis revealed that A-NKC/A-CD14+HLA-DRDIM ratio was an independent predictor for PFS (hazard ratio (HR)=0.56, 95% CI, 0.32-0.96, P<0.03) and OS (HR=0.34, 95% CI, 0.16-0.68, P<0.002). The A-NKC/A-CD14+HLA-DRDIM ratio provides a platform to target specific autograft immune effector cells to improve clinical outcomes in NHL patients undergoing APBHSCT.

Lenalidomide plus R-CHOP21 in newly diagnosed diffuse large B-cell lymphoma (DLBCL): long-term follow-up results from a combined analysis from two phase 2 trials.

Lenalidomide-RCHOP (R2-CHOP21) has been shown to be safe and effective in patients with untreated diffuse large B-cell lymphoma (DLBCL). The aim of this analysis is to report long-term outcome and toxicities in newly diagnosed DLBCL patients who received R2-CHOP21 in two independent phase 2 trials, conducted by Mayo Clinic (MC) and Fondazione Italiana Linfomi (FIL). All patients received R-CHOP21 plus lenalidomide. Long-term progression-free survival (PFS), time to progression (TTP), overall survival (OS) and late toxicities and second tumors were analyzed. Hundred and twelve patients (63 MC, 49 FIL) were included. Median age was 69 years, 88% were stage III-IV. At a median follow-up of 5.1 years, 5y-PFS was 63.5%, 5y-TTP 70.1% and 5y-OS 75.4%; according to cell of origin (COO): 5y-PFS 52.8% vs 64.5%, 5y-TTP 61.6% vs 69.6% and 5y-OS 68.6% vs 74.1% in germinal center (GCB) vs non-GCB respectively. Four patients experienced grade 4-5 late toxicities. Grade ≤ 3 toxicities were infections (N = 4), thrombosis (N = 1) and neuropathy (N = 3). Seven seconds tumors were observed. Long-term follow-up demonstrates that R2-CHOP21 efficacy was maintained with high rates of PFS, TTP, and OS. Lenalidomide appears to mitigate the negative prognosis of non-GCB phenotype. Incidence of therapy-related secondary malignancies and late toxicities were low.

Vitamin D insufficiency is associated with an increased risk of early clinical failure in follicular lymphoma.

We evaluated whether vitamin D insufficiency (VDI; 25(OH)D <20 ng/ml) was associated with adverse outcomes among follicular lymphoma (FL) patients using an observational prospective cohort study of 642 FL patients enrolled from 2002-2012. The median age at diagnosis was 60 years. At a median follow-up of 59 months, 297 patients (46%) had an event (progression, treatment failure), 78 had died and 42 (6.5%) had a lymphoma-related death. VDI was associated with inferior event-free survival (EFS) at 12 months (EFS12, odds ratio (OR)=2.05; 95% confidence interval (CI) 1.18-3.54), overall survival (OS, hazards ratio (HR)=2.35; 95%CI 1.37-4.02), and lymphoma-specific survival (LSS, HR=2.97; 95% CI 1.52-5.80) for the full cohort. Among patients treated with immunochemotherapy (IC), VDI was associated with inferior EFS12 (OR=3.00; 95% CI 1.26-7.13), OS (HR=2.86; 95% CI 1.39-5.85), and LSS (HR=2.96; 95% CI 1.29-6.79). For observed patients, VDI was associated with inferior OS (HR=2.85; 95% CI 1.20-6.76). For other therapies, VDI was associated with inferior OS (HR=3.06; 95% CI 1.01-9.24). Our work is the first to reveal an association of VDI with early clinical failure, and to demonstrate an association of VDI with adverse outcomes among patients who are observed or treated with therapies other than IC. Our findings suggest a potentially modifiable prognostic factor to address in patients with FL.

A phase 1 trial of 90Y-Zevalin radioimmunotherapy with autologous stem cell transplant for multiple myeloma.

This phase 1 study (clinical trial NCT00477815) was conducted to determine the maximum tolerated dose (MTD) of yttrium-90 ibritumomab tiuxetan (90Y-Zevalin) with high dose melphalan (HDM) therapy in multiple myeloma (MM) patients undergoing autologous stem cell transplantation (ASCT). In a 3+3 trial design, 30 patients received rituximab 250 mg/m2 with indium-111 ibritumomab tiuxetan (111In-Zevalin) for dosimetry (day -22); rituximab 250 mg/m2 with escalating doses of 90Y-Zevalin (day -14); melphalan 100 mg/m2 (days -2,-1) followed by ASCT (day 0) and sargramostim (GM-CSF, day 0) until neutrophil engraftment. Each patient's 111In-Zevalin dosimetry data were used to calculate the dose of 90Y-Zevalin (in mCi) to deliver 10, 12, 14, 16, 18 or 20 Gy to the liver. Dose limiting toxicities were seen in 3 patients. The overall response rate was 73% (22/30) with stringent complete response in 2 patients; complete response, 5; very good partial response, 12; and partial response, 3. The median PFS was 16.5 months and the median overall survival was 63.4 months. In MM, the MTD of 90Y-Zevalin with HDM is 18 Gy to the liver. The addition of radiation with novel delivery methods such as radioimmunotherapy combined with standard transplant regimens warrants further study.

Early lymphocyte recovery after autologous stem cell transplantation predicts superior survival in mantle-cell lymphoma.

Autologous stem cell transplantation (ASCT) is an effective treatment strategy for mantle-cell lymphoma (MCL) demonstrating significantly prolonged progression-free survival (PFS) when compared to interferon-alpha maintenance therapy of patients in first remission. The study of absolute lymphocyte count at day 15 (ALC-15) after ASCT as a prognostic factor in non-Hodgkin lymphoma (NHL) included different lymphoma subtypes. The relationship of ALC-15 after ASCT in MCL has not been specifically addressed. We evaluated the impact of ALC-15 recovery on survival of MCL patients undergoing ASCT. We studied 42 consecutive MCL patients who underwent ASCT at the Mayo Clinic in Rochester from 1993 to 2005. ALC-15 threshold was set at 500 cells/microl. The median follow-up after ASCT was 25 months (range, 2-106 months). The median overall survival (OS) and PFS times were significantly better for the 24 patients who achieved an ALC-15 >or=500 cells/microl compared with 18 patients with ALC-15 <500 cells/microl (not reached vs 30 months, P<0.01 and not reached vs 16 months, P<0.0006, respectively). Multivariate analysis demonstrated ALC-15 to be an independent prognostic factor for OS and PFS. The ALC-15 >or=500 cells/microl is associated with a significantly improved clinical outcome following ASCT in MCL.

Autologous hematopoietic stem cell transplantation for older patients with relapsed non-Hodgkin's lymphoma.

To evaluate autologous stem cell transplant (ASCT) in older patients with intermediate grade non-Hodgkin's lymphoma (NHL), the Mayo Clinic Rochester BMT database was reviewed for all patients 60 years of age and older who received ASCT for NHL between September 1995 and February 2003. Factors evaluated included treatment-related mortality (TRM), event-free survival (EFS) and overall survival (OS). Ninety-three patients were identified, including twenty-four (26%) over the age of 70 years. Treatment-related mortality (5.4%) was not significantly different when compared to a younger cohort (2.2%). At a median follow-up of 14 months (0.6-87.6 months), the estimated median survival is 25 months (95% confidence interval (CI) 12-38) in the older group compared to 56 months (95% CI 37-75) (P=0.037) in the younger group. The estimated 4-year EFS was 38% for the older group compared to 42% in the younger cohort (P=0.1). By multivariate analysis, the only factor found to influence survival in the older group was age-adjusted International Prognostic Index at relapse, 0-1 better than 2-3 (P=0.03). Autologous stem-cell transplant can be safely performed in patients 60 years or older with chemotherapy sensitive relapsed or first partial remission NHL. The outcome may not be different from that of younger patients in terms of TRM and EFS.

Allogeneic stem cell transplantation and donor lymphocyte infusions for chronic myelomonocytic leukemia.

Prognosis in chronic myelomonocytic leukemia (CMML) is unfavorable and the optimal therapy remains uncertain. Currently, allogeneic stem cell transplantation is the only known curative therapeutic option. However, the data available are limited and restricted to small retrospective series. There is even less information on the use of donor lymphocyte infusions (DLI) for this disease. We reviewed our experience of allogeneic stem cell transplantation and DLI for adults with CMML. Seventeen consecutive adults underwent allogeneic stem cell transplantation from related (n=14) or unrelated (n=3) donors. Median age was 50 years (range 26-60). Seven patients (41%) demonstrated relapse or persistent disease at a median of 6 months (range 3-55.5). Five patients underwent DLI for morphologic relapse and one for mixed donor chimerism. Two patients achieved durable complete remissions of 15 months each. The overall transplant-related mortality was 41% (n=7). With a median follow-up of 34.5 months, three patients (18%) currently remain alive and in continuous CR. The current study demonstrates a graft-versus-leukemia effect in CMML, both for allogeneic stem cell transplantation and for DLI. Nevertheless, consistent with reported experience of others, overall outcomes remain less than optimal and unpredictable.

A phase I study of 153Sm-EDTMP with fixed high-dose melphalan as a peripheral blood stem cell conditioning regimen in patients with multiple myeloma.

Despite response rates of 30% after high-dose chemotherapy with autologous hematopoietic stem cell transplant, patients with multiple myeloma are not cured. 153Samarium ethylenediaminetetramethylenephosphonate (153Sm-EDTMP; Quadramet) is a short-range, beta-emitting therapeutic radiopharmaceutical with avid skeletal uptake. In total, 12 patients were treated with escalating doses of 153Sm-EDTMP (N=3/group; 6, 12, 19.8, and 30 mCi/kg) and a fixed dose of melphalan (200 mg/m(2)). No dose limiting toxicity was seen. To better standardize the marrow compartment radiation dose, the study was modified such that an additional six patients were treated at a targeted absorbed radiation dose to the red marrow of 40 Gy based on a trace labeled infusion 1 week prior to the therapy. Despite rapid elimination of unbound radiopharmaceutical via kidneys and bladder, no episodes of nephrotoxicity, hemorrhagic cystitis, or delayed radiation nephritis were observed with a median follow-up of 31 months (range 8.5-44). Median times to ANC>0.5 and platelet >20 x 10(6)/l were 12 and 11 days, respectively, with no graft failures. Overall response rate was 94% including seven very good partial responses and five complete responses. Addition of 153Sm EDTMP to melphalan conditioning appears to be safe, well-tolerated and worthy of further study.

Coinhibition of the deubiquitinating enzymes, USP14 and UCHL5, with VLX1570 is lethal to ibrutinib- or bortezomib-resistant Waldenstrom macroglobulinemia tumor cells.

The survival of Waldenstrom macroglobulinemia (WM) tumor cells hinges on aberrant B-cell receptor (BCR) and MYD88 signaling. WM cells upregulate the proteasome function to sustain the BCR-driven growth while maintaining homeostasis. Clinically, two treatment strategies are used to disrupt these complementary yet mutually exclusive WM survival pathways via ibrutinib (targets BTK/MYD88 node) and bortezomib (targets 20 S proteasome). Despite the success of both agents, WM patients eventually become refractory to treatment, highlighting the adaptive plasticity of WM cells and underscoring the need for development of new therapeutics. Here we provide a comprehensive preclinical report on the anti-WM activity of VLX1570, a novel small-molecule inhibitor of the deubiquitinating enzymes (DUBs), ubiquitin-specific protease 14 (USP14) and ubiquitin carboxyl-terminal hydrolase isozyme L5 (UCHL5). Both DUBs reside in the 19 S proteasome cap and their inhibition by VLX1570 results in rapid and tumor-specific apoptosis in bortezomib- or ibrutinib-resistant WM cells. Notably, treatment of WM cells with VLX1570 downregulated BCR-associated elements BTK, MYD88, NFATC, NF-κB and CXCR4, the latter whose dysregulated function is linked to ibrutinib resistance. VLX1570 administered to WM-xenografted mice resulted in decreased tumor burden and prolonged survival (P=0.0008) compared with vehicle-treated mice. Overall, our report demonstrates significant value in targeting USP14/UCHL5 with VLX1570 in drug-resistant WM and carries a high potential for clinical translation.

Factors influencing the retention and chemical stability of poly(ethylene glycol)-lipid conjugates incorporated into large unilamellar vesicles.

Poly(ethylene glycol)(PEG)-lipid anchor conjugates can prolong the circulation lifetimes of liposomes following intravenous injection. In this work we investigate the influence of the lipid anchor and the nature of the chemical link between the PEG and lipid moieties on circulation lifetime. It is shown that incorporation of N-(monomethoxypoly(ethylene glycol)2000-succinyl)-1-palmitoyl-2-oleoylphosphatidylethanolamide (MePEG2000-S-POPE) into large unilamellar vesicles (LUVs) composed of distearoylphosphatidylcholine (DSPC) and cholesterol (DSPC/cholesterol/MePEG2000-S-POPE, 50:45:5, mol/mol) results in only small increases in the circulation lifetimes as observed in mice. This is shown to be due to rapid removal of the hydrophilic coating in vivo, which likely arises from exchange of the entire PEG-lipid conjugate from the liposomal membrane, although chemical breakdown of the PEG-lipid conjugate is also possible. The chemical stability of four different linkages was tested, including succinate, carbamate and amide linkages between MePEG derivatives and the amino head group of PE, as well as a direct link to the phosphate head group of phosphatidic acid (PA). The succinate linkage was found to be the most labile. The anchoring capability of DSPE as compared to POPE in PEG-PE conjugates was also examined. It is shown that incorporation of MePEG2000-S-DSPE conjugates into DSPC/cholesterol LUVs results in little loss of the PEG coating in vivo, long circulation lifetimes and reduced chemical breakdown of the PEG-lipid conjugate. This work establishes that DSPE is a considerably more effective anchor for PEG2000 than POPE and that the chemical stability of PEG-PE conjugates is sensitive to the nature of the linkage and exchangeability of the PEG-PE complex. We suggest that retention of the PEG coating is of paramount importance for prolonged circulation lifetimes.

Efficient encapsulation of antisense oligonucleotides in lipid vesicles using ionizable aminolipids: formation of novel small multilamellar vesicle structures.

Typical methods used for encapsulating antisense oligodeoxynucleotides (ODN) and plasmid DNA in lipid vesicles result in very low encapsulation efficiencies or employ cationic lipids that exhibit unfavorable pharmacokinetic and toxicity characteristics when administered intravenously. In this study, we describe and characterize a novel formulation process that utilizes an ionizable aminolipid (1,2-dioleoyl-3-dimethylammonium propane, DODAP) and an ethanol-containing buffer system for encapsulating large quantities (0.15--0.25 g ODN/g lipid) of polyanionic ODN in lipid vesicles. This process requires the presence of up to 40% ethanol (v/v) and initial formulation at acidic pH values where the DODAP is positively charged. In addition, the presence of a poly(ethylene glycol)-lipid was required during the formulation process to prevent aggregation. The 'stabilized antisense-lipid particles' (SALP) formed are stable on adjustment of the external pH to neutral pH values and the formulation process allows encapsulation efficiencies of up to 70%. ODN encapsulation was confirmed by nuclease protection assays and (31)P NMR measurements. Cryo-electron microscopy indicated that the final particles consisted of a mixed population of unilamellar and small multilamellar vesicles (80--140 nm diameter), the relative proportion of which was dependent on the initial ODN to lipid ratio. Finally, SALP exhibited significantly enhanced circulation lifetimes in mice relative to free antisense ODN, cationic lipid/ODN complexes and SALP prepared with quaternary aminolipids. Given the small particle sizes and improved encapsulation efficiency, ODN to lipid ratios, and circulation times of this formulation compared to others, we believe SALP represent a viable candidate for systemic applications involving nucleic acid therapeutics.

Cd4+ T-cell immune response to large B-cell non-Hodgkin's lymphoma predicts patient outcome.

PURPOSE: Previous studies in patients with non-Hodgkin's lymphoma (NHL) and other malignancies have suggested that the presence of host infiltrates in the tumors of these patients may predict a better outcome. This study was undertaken to determine the prognostic importance of the presence of T cells in the biopsy specimens of patients with B-cell NHL. PATIENTS AND METHODS: Seventy-two patients with diffuse large B-cell NHL were prospectively evaluated at a single institution between 1987 and 1994. The percentage of CD3+, CD3+/HLA-DR+, CD4+, CD8+, and natural killer cells was determined by flow cytometry in the pretreatment diagnostic biopsy specimen and correlated with patient outcome. RESULTS: An increase in the percentage CD4+ T cells in the pretreatment tumor biopsies significantly correlated with patient outcome. The percent of CD4+ T cells was also highly correlated with CD3+/HLA-DR+, CD45RO+, and low L-selectin (CD62L) expression, indicating that the CD4+ T cells are activated memory T-helper cells. Those patients with increased numbers of CD4+ T cells, compared with other patients, had a significantly longer 5-year failure-free survival (72% v 43%, respectively; P =.04), as well as a significantly longer 5-year overall survival (65% v 38%, respectively; P =.05). When evaluated in a multivariate model, the International Prognostic Index and more than 20% infiltrating CD4+ T cells in the pretreatment biopsy were significant independent predictors of relapse-free and overall survival. CONCLUSION: The presence of increased numbers of activated CD4+ cells in the area of B-cell diffuse large-cell NHL predicts a better prognosis. This finding provides a strong rationale for the investigation of cellular immunotherapy in B-cell NHL.

Predictive capacity of the International Prognostic Factor Index in patients with peripheral T-cell lymphoma.

PURPOSE: The International Prognostic Factor Index has been shown to predict the outcome of patients with predominantly B-cell lymphomas classified using traditional classifications, including the Working Formulation, but its prognostic importance has not been tested in a cohort of patients with exclusively T-cell lymphomas. This study was conducted to evaluate the prognostic significance of the International Prognostic Factor Index in patients with peripheral T-cell lymphoma (PTCL). PATIENTS AND METHODS: Seventy-eight patients (48 men and 30 women) with PTCL seen at a single institution between 1985 and 1995 were included in the analysis. The morphology and immunocytochemistry of all the original biopsy specimens were reviewed by a single pathologist and classified using the Revised European-American Lymphoma (REAL) classification. The International Prognostic Factor Index, as well as clinical and biochemical parameters, were evaluated by univariate and multivariate analyses to determine their association with patient outcome. RESULTS: The International Prognostic Factor Index strongly predicted survival when all patients were included in the analysis (P < .001). For patients < or = 60 years, the age-adjusted International Index significantly predicted long-term survival (P = .0218). For patients older than 60 years, the age-adjusted International Index also significantly predicted survival (P = .002). Liver involvement (P = .006) and bone marrow involvement (P = .014) were also significant prognostic factors in the univariate analysis, but only the International Index remained significant in the multivariate analysis (P = .001). CONCLUSION: The International Prognostic Factor Index, which significantly predicts outcome in patients with aggressive/intermediate-grade B-cell lymphomas, has similar prognostic importance in patients with PTCL.

Interleukin 6 induces monocyte chemoattractant protein-1 expression in myeloma cells.

Interleukin 6 (IL-6) is known to play an important role in the biology of the malignant plasma cells in multiple myeloma. In an effort to better understand IL-6 stimulated myeloma cell growth, we have performed gene expression profiling to identify IL-6 early response genes. Using the KAS-6/1 IL-6-dependent human myeloma cell line, IL-6 stimulation dramatically induced expression of monocyte chemoattractant protein-1 (MCP-1) mRNA. To verify this result, we used reverse transcriptase PCR and RNAse protection assays and demonstrated using both assays that MCP-1 is indeed an IL-6 responsive gene in a variety of IL-6-responsive myeloma cell lines. Moreover, we also demonstrated IL-6 stimulated MCP-1 secretion by the myeloma cell lines as well as by fresh patient tumor cells. Lastly, we present evidence that fresh patient tumor cells express mRNA for the MCP-1 receptor, CCR2, as do myeloma cell lines along with a second MCP-1 receptor, CCR11. Although MM cell chemotaxis in response to MCP-1 was only minimal, we were able to demonstrate that MCP-1 stimulated activation of MAPK. Because of the important role that this chemokine plays in both angiogenesis and bone homeostasis, and the ability of MCP-1 to activate myeloma cells, these results suggest a new mechanism by which IL-6 may contribute to disease pathogenesis.

Inhibition of survivin expression suppresses the growth of aggressive non-Hodgkin's lymphoma.

Survivin is a member of the inhibitor of apoptosis protein (IAP) family and functions both as an apoptosis inhibitor and a regulator of cell division. Survivin overexpression is common in many human tumors and correlates with survival in large cell non-Hodgkin's lymphoma. To evaluate this molecule as a potential therapeutic target in large-cell lymphoma, we evaluated the effect of survivin inhibition both in vitro and in vivo. Using an antisense oligonucleotide (ASO) approach, cell growth was significantly inhibited in the DoHH2, RL and HT lymphoma cell lines. In a lymphoma xenograft model, the development of tumors as well as the growth of established tumors was inhibited in the survivin ASO-treated mice compared to controls. To assess the efficacy of the survivin ASO in combination with other biological agents, we combined the survivin ASO with an anti-CD20 monoclonal antibody, rituximab. The effect of survivin ASO and rituximab in combination was additive in vitro. In vivo, however, suppression of tumor growth with the combination was not significantly superior to controls. We conclude that inhibition of survivin expression is an attractive therapeutic strategy in aggressive non-Hodgkin's lymphomas, and that combining survivin ASO with rituximab may enhance the efficacy of this approach.

PD-1 expression defines two distinct T-cell sub-populations in follicular lymphoma that differentially impact patient survival.

To determine the biological and clinical relevance of programmed death 1 (PD-1) in follicular lymphoma (FL), we characterized PD-1(+) T-cell subsets and assessed their biological function as well as potential clinical impact. We found that PD-1 is expressed on intratumoral CD4(+) T cells with both bright and dim intensity, representing two different sub-populations of cells. By immunohistochemistry, we found that CD4(+)PD-1(high) T cells predominantly reside in the lymph node follicles, while PD-1(low) T cells are mainly located in an interfollicular pattern. Intratumoral CD4(+)PD-1(high) T cells have a TFH cell phenotype, express CXCR5, secrete IL-21 and are BCL-6 positive with no TIM-3 expression. In contrast, CD4(+)PD-1(low) T cells have an exhausted phenotype, express TIM-3 and do not express BCL-6 and CXCR5. Functionally, CD4(+)PD-1(high) T cells actively supported B-cell growth, while CD4(+)PD-1(low) T cells displayed a reduced cytokine production and cell-signal transduction. Clinically, we observed that the numbers of CD4(+) or CD8(+)PD-1(low) T cells significantly correlate with a reduced overall survival in FL patients (P=0.007 and 0.04 respectively; n=32). In contrast, the number of CD4(+)PD-1(high) T cells was not associated with patient outcome. Taken together, these results indicated that PD-1 expression defines two sub-populations with distinct functions that differentially impact patient outcome in FL.