Ibrutinib improves survival compared with chemotherapy in mantle cell lymphoma with central nervous system relapse.

Central nervous system (CNS) relapse of mantle cell lymphoma (MCL) is a rare phenomenon with dismal prognosis, where no standard therapy exists. Since the covalent Bruton tyrosine kinase (BTK) inhibitor ibrutinib is effective in relapsed/refractory MCL and penetrates the blood-brain barrier (BBB), on behalf of Fondazione Italiana Linfomi and European Mantle Cell Lymphoma Network we performed a multicenter retrospective international study to investigate the outcomes of patients treated with ibrutinib or chemoimmunotherapy. In this observational study, we recruited patients with MCL with CNS involvement at relapse who received CNS-directed therapy between 2000 and 2019. The primary objective was to compare the overall survival (OS) of patients treated with ibrutinib or BBB crossing chemotherapy. A propensity score based on a multivariable binary regression model was applied to balance treatment cohorts. Eighty-eight patients were included. The median age at study entry was 65 years (range, 39-87), 76% were males, and the median time from lymphoma diagnosis to CNS relapse was 16 months (range, 1-122). Patients were treated with ibrutinib (n = 29, ibrutinib cohort), BBB crossing chemotherapy (ie, high-dose methotrexate ± cytarabine; n = 29, BBB cohort), or miscellaneous treatments (n = 30, other therapy cohort). Both median OS (16.8 vs 4.4 months; P = .007) and median progression-free survival (PFS) (13.1 vs 3.0 months; P = .009) were superior in the ibrutinib cohort compared with the BBB cohort. Multivariable Cox regression model revealed that ibrutinib therapeutic choice was the strongest independent favorable predictive factor for both OS (hazard ratio [HR], 6.8; 95% confidence interval [CI], 2.2-21.3; P < .001) and PFS (HR, 4.6; 95% CI, 1.7-12.5; P = .002), followed by CNS progression of disease (POD) >24 months from first MCL diagnosis (HR for death, 2.4; 95% CI, 1.1-5.3; P = .026; HR for death or progression, 2.3; 95% CI, 1.1-4.6; P = .023). The addition of intrathecal (IT) chemotherapy to systemic CNS-directed therapy was not associated with superior OS (P = .502) as the morphological variant (classical vs others, P = .118). Ibrutinib was associated with superior survival compared with BBB-penetrating chemotherapy in patients with CNS relapse of MCL and should be considered as a therapeutic option.

MYD88 L265P mutation and interleukin-10 detection in cerebrospinal fluid are highly specific discriminating markers in patients with primary central nervous system lymphoma: results from a prospective study.

Reliable biomarkers are needed to avoid diagnostic delay and its devastating effects in patients with primary central nervous system (CNS) lymphoma (PCNSL). We analysed the discriminating sensitivity and specificity of myeloid differentiation primary response (88) (MYD88) L265P mutation (mut-MYD88) and interleukin-10 (IL-10) in cerebrospinal fluid (CSF) of both patients with newly diagnosed (n = 36) and relapsed (n = 27) PCNSL and 162 controls (118 CNS disorders and 44 extra-CNS lymphomas). The concordance of MYD88 mutational status between tumour tissue and CSF sample and the source of ILs in PCNSL tissues were also investigated. Mut-MYD88 was assessed by TaqMan-based polymerase chain reaction. IL-6 and IL-10 messenger RNA (mRNA) was assessed on PCNSL biopsies using RNAscope technology. IL levels in CSF were assessed by enzyme-linked immunosorbent assay. Mut-MYD88 was detected in 15/17 (88%) PCNSL biopsies, with an 82% concordance in paired tissue-CSF samples. IL-10 mRNA was detected in lymphomatous B cells in most PCNSL; expression of IL-6 transcripts was negligible. In CSF samples, mut-MYD88 and high IL-10 levels were detected, respectively, in 72% and 88% of patients with newly diagnosed PCNSL and in 1% of controls; conversely, IL-6 showed a low discriminating sensitivity and specificity. Combined analysis of MYD88 and IL-10 exhibits a sensitivity and specificity to distinguish PCNSL of 94% and 98% respectively. Similar figures were recorded in patients with relapsed PCNSL. In conclusion, high detection rates of mut-MYD88 and IL-10 in CSF reflect, respectively, the MYD88 mutational status and synthesis of this IL in PCNSL tissue. These biomarkers exhibit a very high sensitivity and specificity in detecting PCNSL both at initial diagnosis and relapse. Implications of these findings in patients with lesions unsuitable for biopsy deserve to be investigated.

Prevalence, Characteristics, Risk Factors, and Outcomes of Invasively Ventilated COVID-19 Patients with Acute Kidney Injury and Renal Replacement Therapy.

BACKGROUND: There is no information on acute kidney injury (AKI) and continuous renal replacement therapy (CRRT) among invasively ventilated coronavirus disease 2019 (COVID-19) patients in Western healthcare systems. OBJECTIVE: To study the prevalence, characteristics, risk factors and outcome of AKI and CRRT among invasively ventilated COVID-19 patients. METHODS: Observational study in a tertiary care hospital in Milan, Italy. RESULTS: Among 99 patients, 72 (75.0%) developed AKI and 17 (17.7%) received CRRT. Most of the patients developed stage 1 AKI (33 [45.8%]), while 15 (20.8%) developed stage 2 AKI and 24 (33.4%) a stage 3 AKI. Patients who developed AKI or needed CRRT at latest follow-up were older, and among CRRT treated patients a greater proportion had preexisting CKD. Hospital mortality was 38.9% for AKI and 52.9% for CRRT patients. CONCLUSIONS: Among invasively ventilated COVID-19 patients, AKI is very common and CRRT use is common. Both carry a high risk of in-hospital mortality.

The first case of COVID-19 treated with the complement C3 inhibitor AMY-101.

Acute respiratory distress syndrome (ARDS) is a devastating clinical manifestation of COVID-19 pneumonia and is mainly based on an immune-driven pathology. Mounting evidence suggests that COVID-19 is fueled by a maladaptive host inflammatory response that involves excessive activation of innate immune pathways. While a "cytokine storm" involving IL-6 and other cytokines has been documented, complement C3 activation has been implicated as an initial effector mechanism that exacerbates lung injury in preclinical models of SARS-CoV infection. C3-targeted intervention may provide broader therapeutic control of complement-mediated inflammatory damage in COVID-19 patients. Herein, we report the clinical course of a patient with severe ARDS due to COVID-19 pneumonia who was safely and successfully treated with the compstatin-based complement C3 inhibitor AMY-101.

Interleukin-1 receptor-associated kinase 4 inhibitor interrupts toll-like receptor signalling and sensitizes chronic lymphocytic leukaemia cells to apoptosis.

Chronic lymphocytic leukaemia (CLL) cells are strongly influenced by microenvironmental signals through the activation of distinct membrane receptors including the B-cell receptor and toll-like receptors (TLR). Recapitulating TLR stimulation in vitro by treating CLL cells with the TLR9 ligand CpG can induce metabolic activation and protection from apoptosis. We hypothesized that interfering with TLR signalling may be beneficial for treating CLL, and we tested in preclinical studies the effect of a specific interleukin-1 receptor-associated kinase 4 (IRAK4) inhibitory small molecule on primary leukaemic cells isolated from the peripheral blood of patients. We observed that IRAK4, an upstream kinase of the TLR pathway, is expressed in patients with CLL, and lower IRAK4 mRNA levels associate with a better outcome. The specific IRAK4 inhibitor disrupted TLR signalling as assessed by reduction of the specific biomarkers NFKBIZ and interleukin-6 mRNAs, and restrained the protective effect of in vitro TLR stimulation on cell viability. To note, IRAK4 inhibitor induced p53 and triggered apoptosis. Co-treatment of CLL cells with increasing concentrations of IRAK4i and the Bruton tyrosine kinase inhibitor ibrutinib demonstrated a synergistic effect. Our results suggest that targetting IRAK4 may represent a novel approach in CLL and may be combined with other signalling inhibitors.

Long-lasting efficacy and safety of lenalidomide maintenance in patients with relapsed diffuse large B-cell lymphoma who are not eligible for or failed autologous transplantation.

We report final results of a phase II trial addressing efficacy and feasibility of lenalidomide maintenance in patients with chemosensitive relapse of diffuse large B-cell lymphoma (DLBCL) not eligible for or failed after autologous stem cell transplantation (ASCT). Patients with relapsed DLBCL who achieved at least a partial response to salvage chemoimmunotherapy were enrolled and treated with lenalidomide 25 mg/day for 21 of 28 days for 2 years or until progression or unacceptable toxicity. Primary endpoint was 1-year PFS. Forty-six of 48 enrolled patients were assessable. Most patients had IPI ≥2, advanced stage and extranodal disease before the salvage treatment that led to trial registration; 28 (61%) patients were older than 70 years. Lenalidomide was well tolerated. With the exception of neutropenia, grade-4 toxicities occurred in <1% of courses. Three patients died of complications during maintenance and three died due to second cancers at 32 to 64 months. There were 13 SAEs recorded in 12 patients; all these patients but two recovered. Lenalidomide was interrupted due to toxicity in other 6 patients, and 25 patients required dose reduction (transient in 21). At 1 year from registration, 31 patients were progression free. After a median follow-up of 65 (range 39-124) months, 22 patients remain progression free, with a 5-year PFS of 48% ± 7%. The duration of response to lenalidomide was longer than response to prior treatment in 30 (65%) patients. Benefit was observed both in de novo and transformed DLBCL, germinal-center-B-cell and nongerminal-center-B-cell subtypes. Twenty-six patients are alive (5-year OS 62% ± 7%). With the limitations of a nonrandomized design, these long-term results suggest that lenalidomide maintenance might bring benefit to patients with chemosensitive relapse of DLBCL not eligible for or failed after ASCT. Lenalidomide was associated with durable disease control and was well tolerated in this elderly population. Further investigations on immunomodulatory drugs as maintenance in these high-risk patients are warranted.

Axicabtagene ciloleucel treatment is more effective in primary mediastinal large B-cell lymphomas than in diffuse large B-cell lymphomas: the Italian CART-SIE study.

Axicabtagene ciloleucel showed efficacy for relapsed/refractory large B-cell lymphomas (LBCL), including primary mediastinal B-cell lymphomas (PMBCL); however, only few PMBCLs were reported. Aim was to evaluate efficacy and safety of axicabtagene ciloleucel in patients with PMBCL compared to those with other LBCL, enrolled in the Italian prospective observational CART-SIE study. PMBCLs (n = 70) were younger, with higher percentage of bulky and refractory disease, compared to other LBCLs (n = 190). Median follow-up time for infused patients was 12.17 months (IQR 5.53,22.73). The overall (complete + partial) response rate (ORR,CR + PR) after bridging was 41% for PMBCL and 28% for other LBCL, p = 0.0102. Thirty days ORR was 78% (53/68) with 50% (34) CR in PMBCL, and 75% (141/187) with 53% (100) CR in other LBCL, p = 0.5457. Ninety days ORR was 69% (45/65) with 65% (42) CR in PMBCL, and 54% (87/162) with 47% (76) CR in other LBCL; progressive disease was 21% in PMBCL and 45% in other LBCL, p = 0.0336. Twelve months progression-free survival was 62% (95% CI: 51-75) in PMBCL versus 48% (95% CI: 41-57) in other LBCL, p = 0.0386. Twelve months overall survival was 86% (95% CI: 78-95) in PMBCL versus 71% (95% CI: 64-79) in other LBCL, p = 0.0034. All grade cytokine release syndrome was 88% (228/260); all grade neurotoxicity was 34% (88/260), with 6% of fatal events in PMBCL. Non-relapse mortality was 3%. In conclusion, PMBCLs achieved significantly better response and survival rates than other LBCLs.

Safety and efficacy of a dose-dense short-term therapy in patients with MYC-translocated aggressive lymphoma.

Patients with aggressive B-cell lymphoma and MYC rearrangement at fluorescence in situ hybridization exhibit poor outcome after R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone). In the last decade, 68 patients with Burkitt lymphoma ([BL] n = 46) or high-grade B-cell lymphoma ([HGBCL] single, double, or triple hit; n = 22) were treated with a dose-dense, short-term therapy termed "CARMEN regimen" at 5 Italian centers. Forty-six (68%) patients were HIV+. CARMEN included a 36-day induction with sequential, single weekly doses of cyclophosphamide, vincristine, rituximab, methotrexate, etoposide, and doxorubicin plus intrathecal chemotherapy, followed by high-dose-cytarabine-based consolidation. Patients who did not achieve complete remission (CR) after induction received BEAM (carmustina, etoposide, cytarabine, melfalan)-conditioned autologous stem cell transplantation (ASCT) after consolidation. Sixty-one (90%) patients completed induction, and 59 (87%) completed consolidation. Seventeen patients received ASCT. Grade 4 hematological toxicity was common but did not cause treatment discontinuation; grade 4 nonhematological toxicity was recorded in 11 (16%) patients, with grade 4 infections in 6 (9%). Six (9%) patients died of toxicity (sepsis in 4, COVID-19, acute respiratory distress syndrome). CR rate after the whole treatment was 73% (95% confidence interval [CI], 55% to 91%) for patients with HGBCL and 78% (95% CI, 66% to 90%) for patients with BL. At a median follow-up of 65 (interquartile range, 40-109) months, 48 patients remain event free, with a 5-year progression-free survival of 63% (95% CI, 58% to 68%) for HGBCL and 72% (95% CI, 71% to 73%) for BL, with a 5-year overall survival (OS) of 63% (95% CI, 58% to 68%) and 76% (95% CI, 75% to 77%), respectively. HIV seropositivity did not have a detrimental effect on outcome. This retrospective study shows that CARMEN is a safe and active regimen both in HIV-negative and -positive patients with MYC-rearranged lymphomas. Encouraging survival figures, attained with a single dose of doxorubicin and cyclophosphamide, deserve further investigation in HGBCL and other aggressive lymphomas.

Continuous positive airway pressure and pronation outside the Intensive Care Unit in COVID-19 acute respiratory distress syndrome.

BACKGROUND: The efficacy and safety of continuous positive airway pressure and respiratory physiotherapy outside the Intensive Care Unit during a pandemic. METHODS: In this cohort study performed in February-May 2020 in a large teaching hospital in Milan, COVID-19 patients with adult respiratory distress syndrome receiving continuous positive airway pressure (positive end-expiratory pressure =10 cm H2O, FiO2=0.6, daily treatment duration: 4×3h-cycles) and respiratory physiotherapy including pronation outside the Intensive Care Unit were followed-up. RESULTS: Of 90 acute respiratory distress syndrome (ARDS) patients treated with continuous positive airway pressure (45/90, 50% pronated at least once) outside the Intensive Care Unit and with a median (interquartile) follow-up of 37 (11-46) days, 45 (50%) were discharged at home, 28 (31%) were still hospitalized, and 17 (19%) died. Continuous positive airway pressure failure was recorded for 35 (39%) patients. Patient mobilization was associated with reduced failure rates (P=0.033). No safety issues were observed. CONCLUSIONS: Continuous positive airway pressure with patient mobilization (including pronation) was effective and safe in patients with ARDS due to COVID-19 managed outside the Intensive Care Unit setting during the pandemic.

Role of NFAT in Chronic Lymphocytic Leukemia and Other B-Cell Malignancies.

In recent years significant progress has been made in the clinical management of chronic lymphocytic leukemia (CLL) as well as other B-cell malignancies; targeting proximal B-cell receptor signaling molecules such as Bruton Tyrosine Kinase (BTK) and Phosphoinositide 3-kinase (PI3Kδ) has emerged as a successful treatment strategy. Unfortunately, a proportion of patients are still not cured with available therapeutic options, thus efforts devoted to studying and identifying new potential druggable targets are warranted. B-cell receptor stimulation triggers a complex cascade of signaling events that eventually drives the activation of downstream transcription factors including Nuclear Factor of Activated T cells (NFAT). In this review, we summarize the literature on the expression and function of NFAT family members in CLL where NFAT is not only overexpressed but also constitutively activated; NFAT controls B-cell anergy and targeting this molecule using specific inhibitors impacts on CLL cell viability. Next, we extend our analysis on other mature B-cell lymphomas where a distinct pattern of expression and activation of NFAT is reported. We discuss the therapeutic potential of strategies aimed at targeting NFAT in B-cell malignancies not overlooking the fact that NFAT may play additional roles regulating the inflammatory microenvironment.

Improving the antitumor activity of R-CHOP with NGR-hTNF in primary CNS lymphoma: final results of a phase 2 trial.

Rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is the standard treatment of diffuse large B-cell lymphoma (DLBCL). Primary DLBCL of the central nervous system (CNS) (primary central nervous system lymphoma [PCNSL]) is an exception because of the low CNS bioavailability of related drugs. NGR-human tumor necrosis factor (NGR-hTNF) targets CD13+ vessels, enhances vascular permeability and CNS access of anticancer drugs, and provides the rationale for the treatment of PCNSL with R-CHOP. Herein, we report activity and safety of R-CHOP preceded by NGR-hTNF in patients with PCNSL relapsed/refractory to high-dose methotrexate-based chemotherapy enrolled in a phase 2 trial. Overall response rate (ORR) was the primary endpoint. A sample size of 28 patients was considered necessary to demonstrate improvement from 30% to 50% ORR. NGR-hTNF/R-CHOP would be declared active if ≥12 responses were recorded. Treatment was well tolerated; there were no cases of unexpected toxicities, dose reductions or interruptions. NGR-hTNF/R-CHOP was active, with confirmed tumor response in 21 patients (75%; 95% confidence interval, 59%-91%), which was complete in 11. Seventeen of the 21 patients with response to treatment received consolidation (ASCT, WBRT, and/or lenalidomide maintenance). At a median follow-up of 21 (range, 14-31) months, 5 patients remained relapse-free and 6 were alive. The activity of NGR-hTNF/R-CHOP is in line with the expression of CD13 in both pericytes and endothelial cells of tumor vessels. High plasma levels of chromogranin A, an NGR-hTNF inhibitor, were associated with proton pump inhibitor use and a lower remission rate, suggesting that these drugs should be avoided during TNF-based therapy. Further research on this innovative approach to CNS lymphomas is warranted. The trial was registered as EudraCT: 2014-001532-11.

GM-CSF blockade with mavrilimumab in severe COVID-19 pneumonia and systemic hyperinflammation: a single-centre, prospective cohort study.

BACKGROUND: Mortality in patients with COVID-19 pneumonia and systemic hyperinflammation is high. We aimed to examine whether mavrilimumab, an anti-granulocyte-macrophage colony-stimulating factor receptor-α monoclonal antibody, added to standard management, improves clinical outcomes in patients with COVID-19 pneumonia and systemic hyperinflammation. METHODS: This single-centre prospective cohort study included patients aged 18 years or older who were admitted to San Raffaele Hospital (Milan, Italy) with severe COVID-19 pneumonia, hypoxia, and systemic hyperinflammation. Patients received a single intravenous dose (6 mg/kg) of mavrilimumab added to standard care given by the hospital at the time. The control group consisted of contemporaneous patients with similar baseline characteristics who received standard care at the same hospital. The main outcome was time to clinical improvement (defined as improvement of two or more points on the seven-point ordinal scale of clinical status). Other outcomes included proportion of patients achieving clinical improvement, survival, mechanical ventilation-free survival, and time to fever resolution. Adverse events were monitored daily. FINDINGS: Between March 17 and April 15, 2020, 13 non-mechanically ventilated patients (median age 57 years [IQR 52-58], 12 [92%] men) received mavrilimumab and 26 patients (median age 60 [IQR 53-67], 17 [65%] men) in the control group received standard care. During the 28-day follow-up, no patients in the mavrilimumab group died, and seven (27%) patients in the control group died (p=0·086). At day 28, all patients in the mavrilimumab group and 17 (65%) patients in the control group showed clinical improvement (p=0·030), with earlier improvement in the mavrilimumab than in the control group (mean time to improvement 8 days [IQR 5 to 11] vs 19 days [11 to >28], p=0·0001). By day 28, one (8%) patient in the mavrilimumab group progressed to mechanical ventilation compared with nine (35%) patients in the control group who progressed to mechanical ventilation or died (p=0·14). By day 14, fever resolved in ten (91%) of 11 febrile patients in the mavrilimumab group, compared with 11 (61%) of 18 febrile patients in the control group (p=0·18); fever resolution was faster in mavrilimumab recipients versus controls (median time to resolution 1 day [IQR 1 to 2] vs 7 days [3 to >14], p=0·0093). Mavrilimumab was well tolerated, with no infusion reactions. Three (12%) patients in the control group developed infectious complications. INTERPRETATION: Mavrilimumab treatment was associated with improved clinical outcomes compared with standard care in non-mechanically ventilated patients with severe COVID-19 pneumonia and systemic hyperinflammation. Treatment was well tolerated. Confirmation of efficacy requires controlled testing. FUNDING: IRCCS San Raffaele Scientific Institute.

Diagnostic and Clinical Impact of Staging 18F-FDG PET/CT in Mantle-Cell Lymphoma: A Two-Center Experience.

INTRODUCTION: The diagnostic accuracy of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) in staging mantle-cell lymphoma has not yet investigated. The aim of this 2-center retrospective study was to investigate the utility of 18F-FDG PET/CT in assessing nodal, splenic, bone marrow (BM), and gastrointestinal (GI) disease compared to CT, BM, and GI endoscopy; and to assess its clinical impact. PATIENTS AND METHODS: One hundred twenty-two patients with histologically proven mantle-cell lymphoma were included. PET/CT BM findings were considered positive if isolated/multiple focal uptake in the BM not explained by benign findings and/or diffuse BM uptake higher than liver with/without focal uptakes were present. PET/CT findings were considered positive for GI involvement in the presence of isolated/multiple focal uptake in the GI organ. RESULTS: All patients had positive PET/CT showing the presence of at least one hypermetabolic lesion, with the exception of one case. PET/CT results, compared to CT, detected more nodal and/or splenic lesions in 26 patients. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of PET/CT for BM were 52%, 98%, 97%, 65%, and 74%; for GI 64%, 91%, 69%, 90%, and 85%; and for GI excluding diabetic patients, 78%, 92%, 72%, 94%, and 89%. PET/CT permitted upstaging of 21 cases and downstaging of 2. CONCLUSION: 18F-FDG PET/CT showed excellent detection rate in nodal and splenic disease-a rate better than CT. For BM and GI evaluation, in order to reach good accuracy, the selection of patients and the use of specific criteria for evaluation of these organs seems to be crucial. Moreover, PET/CT altered the management and therapeutic approach in about 20% of patients.

Monoclonal B-cell lymphocytosis: Does the elderly patient need a specialistic approach?

Monoclonal B-cell lymphocytosis (MBL) is defined by the presence of a monoclonal B-cell population in the peripheral blood (PB) at a concentration of <5 × 109/l and no signs or symptoms of a lymphoproliferative disorder. In around 75% of cases, the immunophenotype of the clonal B-cell expansions is superimposable to that of chronic lymphocytic leukemia (CLL), thus defined "CLL-like". Other cases may coexpress CD19, CD5, bright CD20, and lack CD23 ("atypical CLL"), while others are CD5-negative ("non-CLL"). Beside the immunophenotypic profile, a key distinction is based on the B-cell count, stratifying the MBL category in low (<0.5 × 109/l) or high-count (≥0.5 × 109/l). Low-count (LC) MBL is recognized in general population studies and it is not associated with lymphocytosis. High-count (HC) MBL is identified during the clinical work-up for lymphocytosis and carries a risk of progression to CLL requiring therapy of 1-2% per year in most series, warranting clinical monitoring over time. At the time of MBL diagnosis, the key point is the careful evaluation and exclusion of differential diagnoses. After the initial workup, the follow-up at a referral center by a hematologist would be desirable as, in addition to the obvious risk of progression to clinically relevant CLL, the appropriate management of MBL individuals should take into account the risk of developing infections, other cancers and autoimmune disorders. For those cases who indeed bear a risk, though limited, of clinical consequences, such as the majority of HC-MBL cases, current evidences suggest that they may benefit from a tailored and specialized approach.

Transcriptional mechanism of vascular endothelial growth factor-induced expression of protein kinase CßII in chronic lymphocytic leukaemia cells.

A key feature of chronic lymphocytic leukaemia (CLL) cells is overexpressed protein kinase CßII (PKCßII), an S/T kinase important in the pathogenesis of this and other B cell malignancies. The mechanisms contributing to enhanced transcription of the gene coding for PKCßII, PRKCB, in CLL cells remain poorly described, but could be important because of potential insight into how the phenotype of these cells is regulated. Here, we show that SP1 is the major driver of PKCßII expression in CLL cells where enhanced association of this transcription factor with the PRKCB promoter is likely because of the presence of histone marks permissive of gene activation. We also show how vascular endothelial growth factor (VEGF) regulates PRKCB promoter function in CLL cells, stimulating PKCß gene transcription via increased association of SP1 and decreased association of STAT3. Taken together, these results are the first to demonstrate a clear role for SP1 in the up regulation of PKCßII expression in CLL cells, and the first to link SP1 with the pathogenesis of this and potentially other B cell malignancies where PKCßII is overexpressed.