Developmental partitioning of SYK and ZAP70 prevents autoimmunity and cancer.

Even though SYK and ZAP70 kinases share high sequence homology and serve analogous functions, their expression in B and T cells is strictly segregated throughout evolution. Here, we identified aberrant ZAP70 expression as a common feature in a broad range of B cell malignancies. We validated SYK as the kinase that sets the thresholds for negative selection of autoreactive and premalignant clones. When aberrantly expressed in B cells, ZAP70 competes with SYK at the BCR signalosome and redirects SYK from negative selection to tonic PI3K signaling, thereby promoting B cell survival. In genetic mouse models for B-ALL and B-CLL, conditional expression of Zap70 accelerated disease onset, while genetic deletion impaired malignant transformation. Inducible activation of Zap70 during B cell development compromised negative selection of autoreactive B cells, resulting in pervasive autoantibody production. Strict segregation of the two kinases is critical for normal B cell selection and represents a central safeguard against the development of autoimmune disease and B cell malignancies.

Normal B cells express ZAP70 in chronic lymphocytic leukemia: A link between autoimmunity and lymphoproliferation?

ZAP70 has a prognostic value in chronic lymphocytic leukemia (CLL), through altered B-cell receptor signaling, which is important in CLL pathogenesis. A good correlation between ZAP70 expression in CLL cells and the occurrence of autoimmune phenomena has been reported. Yet, the great majority of CLL-associated autoimmune cytopenia is due to polyclonal immunoglobulin (Ig) G synthesized by nonmalignant B cells, and this phenomenon is poorly understood. Here, we show, using flow cytometry, that a substantial percentage of CD5- nonmalignant B cells from CLL patients expresses ZAP70 compared with CD5- B cells from healthy subjects. This ZAP70 expression in normal B cells from CLL patients was also evidenced by the detection of ZAP70 mRNA at single-cell level with polyclonal Ig heavy- and light-chain gene transcripts. ZAP70+ normal B cells belong to various B-cell subsets and their presence in the naïve B-cell subset suggests that ZAP70 expression may occur during early B-cell development in CLL patients and potentially before malignant transformation. The presence of ZAP70+ normal B cells is associated with autoimmune cytopenia in CLL patients in our cohort of patients, and recombinant antibodies produced from these ZAP70+ nonmalignant B cells were frequently autoreactive including anti-platelet reactivity. These results provide a better understanding of the implication of ZAP70 in CLL leukemogenesis and the mechanisms of autoimmune complications of CLL.

Commercial anti-CD19 CAR T cell therapy for patients with relapsed/refractory aggressive B cell lymphoma in a European center.

Two autologous anti-CD19 chimeric antigen receptors (CAR) T cells (axicabtagene ciloleucel [axi-cel] and tisagenlecleucel [tisa-cel]) are commercially approved in Europe for relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). We performed a retrospective study to evaluate patterns of use, efficacy and safety for axi-cel and tisa-cel. Data from 70 patients who underwent apheresis for commercial CAR T cells between January 2018 and November 2019 in our institution were retrospectively collected. Sixty-one patients were infused. The median age at infusion was 59 years old (range 27-75 years). The median number of prior therapies was 3 (range, 2-6). The overall response rates (ORRs) at 1 month and 3 months were 63% and 45%, respectively, with 48% and 39% achieving a complete response (CR), respectively. After a median follow-up after infusion of 5.7 months, the median progression-free survival (PFS) was 3.0 months (95% CI, 2.8-8.8 months), and the median overall survival (OS) was 11.8 months (95% CI, 6.0-12.6 months). In multivariate analysis, factors associated with poor PFS were the number of previous lines of treatment before CAR T cells (≥4) (P = .010) and a C reactive protein (CRP) value >30 mg/L at the time of lymphodepletion (P < .001). Likewise, the only factor associated with a shorter OS was CRP >30 mg/L (P = .009). Cytokine release syndrome (CRS) of any grade occurred in 85% of patients, including 8% of patients with CRS of grade 3 or higher. Immune cell-associated neurotoxicity syndrome (ICANS) of any grade occurred in 28% of patients, including 10% of patients with ICANS of grade 3 or higher. Regarding efficacy and safety, no significant difference was found between axi-cel and tisa-cel. This analysis describes one of the largest real-life cohorts of patients treated with axi-cel and tisa-cel for R/R aggressive B cell lymphoma in Europe.

Refractory diffuse large B-cell lymphoma after first-line immuno-CT: Treatment options and outcomes.

In the rituximab era, one-third of diffuse large B-cell lymphoma patients experience relapse/refractory disease after first-line anthracycline-based immunochemotherapy. Optimal management remains an unmet medical need. The aim of this study was to report the outcomes of a cohort of refractory patients according to their patterns of refractoriness and the type of salvage option. We performed a retrospective analysis, which included 104 diffuse large B-cell lymphoma patients treated at Lyon Sud University Hospital (2002-2017) who presented with refractory disease. Refractoriness was defined as progressive/stable disease during first-line treatment (primary refractory, N = 47), a partial response after the end of first-line treatment that required subsequent treatment (residual disease, N = 19), or relapse within 1 year of diagnosis after an initial complete response (CR) (early relapse, N = 38). The 2-year overall survival (OS) rates for primary refractory, early relapse, and residual disease patients were 27%, 25%, and 52%, respectively, while the event-free survival rates for those groups were 13%, 13%, and 42%, respectively. In a univariate analysis, lactate dehydrogenase level, Ann Arbor stage, poor performance status, high age-adjusted International Prognostic Index score, and age > 65 years were associated with shorter OS. The use of rituximab and platinum-based chemo during the first salvage treatment was associated with prolonged OS. In a multivariate analysis, age (HR:2.06) and rituximab use (HR:0.54) were associated with OS. Among patients <65 years who achieved a CR, autologous stem-cell transplant was associated with higher 2-year OS (90% vs 74%, P = 0.10). Patients who were treated with a targeted therapy in the context of a clinical trial after second-line treatment had a higher 2-year OS (34% vs 19%, P = 0.06). In conclusion, patients with primary refractory disease or early relapse have very poor outcomes but may benefit from rituximab retreatment during the first salvage treatment.

HLA-DR expression on monocytes and outcome of anti-CD19 CAR T-cell therapy for large B-cell lymphoma.

Despite their unprecedented success in relapsed/refractory (R/R) large B-cell lymphoma (LBCL), anti-CD19 CAR T cells are associated with significant toxicity, and more than half of patients relapse. As monocytes emerged as key players in CAR therapy, we sought to evaluate the evolution of HLA-DR expression on monocytes (mHLA-DR) before and after commercial anti-CD19 CAR T-cell infusion in a large cohort (n = 103) of patients with R/R LBCL and its association with adverse events and treatment response. Cy-Flu-based lymphodepletion (LD) upregulated mHLA-DR in 79% of the cases, whereas in 2l% of cases (15 patients), the mHLA-DR level decreased after LD, and this decrease was associated with poorer outcome. Low mHLA-DR at day minus 7 (D-7) (<13 500 antibodies per cell) before CAR T-cell infusion correlated with older age, poorer performance status, higher tumor burden, and elevated inflammatory markers. With a median follow-up of 7.4 months, patients with low mHLA-DR D-7 exhibited a poorer duration of response and survival than the higher mHLA-DR D-7 group. For toxicity management, tocilizumab was more frequently used in the low-mHLA-DR D-7 group. These data suggest that monocyte dysregulation before LD, characterized by the downregulation of mHLA-DR, correlates with an inflammatory and immunosuppressive tumor environment and is associated with failure of anti-CD19 CAR T cells in patients with R/R LBCL. Modulation of these myeloid cells represents a promising field for improving CAR therapy.

Rituximab in combination with adapted-dose of ifosfamide and etoposide as salvage treatment in elderly refractory/relapsed diffuse large B-cell lymphoma patients non-candidate for high dose therapy: a retrospective study.

We retrospectively reviewed for 72 relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) patients ineligible for autologous stem-cell transplantation (ASCT) treated between 2004 and 2017, efficacy and safety profile of rituximab (375 mg/m2) in combination with etoposide (300 mg/m2) and ifosfamide (1500 mg/m2) at 2, 3, or 4-week intervals. Median age was 79 years (range, 64-92). The median number of previous line was 1 (range 1-8). Patients received a median of six cycles (1-12). Fourteen patients (19%) presented partial and 14 complete responses (19%). Among the 369 cycles, nine patients developed febrile neutropenia (13%), 14 a grade 3-4 neutropenia (19%), 7 a grade 3-4 thrombocytopenia (10%) without grade 3-4 non-hematological toxicity. With a median follow up of 7.8 months, the median progression-free survival, overall survival, and duration of response were 4.4 months, 9.4 months, and 12 months, respectively. This regimen represents a therapeutic option in R/R DLBCL patients ineligible to ASCT.

Clinicopathological features and survival in EBV-positive diffuse large B-cell lymphoma not otherwise specified.

In this retrospective study, we report 70 cases of Epstein-Barr virus (EBV)+ diffuse large B-cell lymphoma not otherwise specified (DLBCL-NOS) among 1696 DLBCL-NOS cases diagnosed between 2006 and 2019 (prevalence of 4.1%). At diagnosis, median age was 68.5 years; 79% of the cases presented with an advanced-stage disease (III-IV), 48% with extranodal lesions, and 14% with an hemophagocytic lymphohistiocytosis (HLH) (8 at diagnosis and 1 on therapy). A total of 46 cases presented a polymorphic pattern, and 21 were monomorphic. All had a non-germinal center B phenotype, with the majority of tumor cells expressing CD30 and programmed death ligand 1 (98% and 95%, respectively). Type II and III EBV latency was seen in 88% and 12% of the cases, respectively. Patients were treated with immunochemotherapy (59%) or chemotherapy (22%), and 19% received palliative care due to advanced age and altered performance status. After a median follow-up of 48 months, progression-free survival (PFS) and overall survival (OS) at 5 years were 52.7% and 54.8%, respectively. Older age (>50 years) and HLH were associated with shorter PFS and OS in multivariate analysis (PFS: hazard ratio [HR], 14.01; 95% confidence interval [CI], 2.34-83.97; and HR, 5.78; 95% CI, 2.35-14.23; OS: HR, 12.41; 95% CI, 1.65-93.53; and HR, 6.09; 95% CI, 2.42-15.30, respectively). Finally, using a control cohort of 425 EBV- DLBCL-NOS, EBV positivity was associated with a shorter OS outcome within patients >50 years (5-year OS, 53% [95% CI, 38.2-74] vs 60.8% [95% CI, 55.4-69.3], P = .038), but not in younger patients.

Prognostic Impact of 18F-FDG PET/CT in Patients With Aggressive B-Cell Lymphoma Treated With Anti-CD19 Chimeric Antigen Receptor T Cells.

PURPOSE OF THE REPORT: We aimed to evaluate the role of 18F-FDG PET/CT in predicting patient outcome following chimeric antigen receptor T (CAR T) cells infusion in aggressive B-cell lymphoma. METHODS: 18F-FDG PET/CT data before leukapheresis, before CAR T-cell infusion and 1 month (M1) after CAR T-cell infusion, from 72 patients were retrospectively analyzed. SUVmax, total lesion glycolysis (TLG), metabolic tumor volume (MTV), and parameters describing tumor kinetics were calculated for each 18F-FDG PET/CT performed. The aim was to evaluate the prognostic value of 18F-FDG PET/CT metabolic parameters for predicting progression-free survival (PFS) and overall survival (OS) following CAR T-cell therapy. RESULTS: Regarding PFS, ∆MTVpre-CAR and ∆TLGpre-CAR were found to be more discriminating compared with metabolic parameters at preinfusion. Median PFS in patients with a ∆MTVpre-CAR of less than 300% was 6.8 months (95% confidence interval [CI], 2.8 months to not reached) compared with 2.8 months (95% CI, 0.9-3.0 months) for those with a value of 300% or greater (P = 0.004). Likewise, median PFS in patients with ∆TLGpre-CAR of less than 420% was 6.8 months (95% CI, 2.8 months to not reached) compared with 2.7 months (95% CI, 1.3-3.0 months) for those with a value of 420% or greater (P = 0.0148). Regarding OS, metabolic parameters at M1 were strongly associated with subsequent outcome. SUVmax at M1 with a cutoff value of 14 was the most predictive parameter in multivariate analysis, outweighing other clinicobiological variables (P < 0.0001). CONCLUSIONS: Disease metabolic volume kinetics before infusion of CAR T cells seems to be superior to initial tumor bulk itself for predicting PFS. For OS, SUVmax at M1 might adequately segregate patients with different prognosis.