Dynamic variation of CD5 surface expression levels within individual chronic lymphocytic leukemia clones.

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of clonally derived mature CD5high B cells; however, the cellular origin of CLL is still unknown. Patients with CLL also harbor variable numbers of CD5low B cells, but the clonal relationship of these cells to the bulk disease is unknown and can have important implications for monitoring, treating, and understanding the biology of CLL. Here, we use B-cell receptors (BCRs) as molecular barcodes to first show by single-cell BCR sequencing that the great majority of CD5low B cells in the blood of CLL patients are clonally related to CD5high CLL B cells. We investigate whether CD5 state switching was likely to occur continuously as a common event or as a rare event in CLL by tracking somatic BCR mutations in bulk CLL B cells and using them to reconstruct the phylogenetic relationships and evolutionary history of the CLL in four patients. Using statistical methods, we show that there is no parsimonious route from a single or low number of CD5low switch events to the CD5high population, but rather, large-scale and/or dynamic switching between these CD5 states is the most likely explanation. The overlapping BCR repertoires between CD5high and CD5low cells from CLL patient peripheral blood reveal that CLL exists in a continuum of CD5 expression. The major proportion of CD5low B cells in patients are leukemic, thus identifying CD5low B cells as an important component of CLL, with implications for CLL pathogenesis, clinical monitoring, and the development of anti-CD5-directed therapies

Copanlisib for the Treatment of Malignant Lymphoma: Clinical Experience and Future Perspectives.

Dysregulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin signaling is common in both indolent and aggressive forms of malignant lymphoma, for which several targeted therapies have been developed. Copanlisib is a highly selective and potent intravenous pan-class I PI3K inhibitor that has demonstrated durable objective responses and a manageable safety profile in heavily pre-treated patients with indolent lymphomas. As a result, copanlisib monotherapy received accelerated approval from the US Food and Drug Administration for the treatment of adults with relapsed follicular lymphoma who have received at least two systemic therapies, and breakthrough designation for patients with pre-treated relapsed or refractory marginal zone lymphoma. Hyperglycemia and hypertension are among the most frequently reported adverse events with copanlisib monotherapy, and are infusion-related, transient, and manageable with standard therapies. Mild diarrhea is also a common adverse event with copanlisib monotherapy; there is no evidence of worsening severity of diarrhea, or serious gastrointestinal toxicities such as colitis or severe liver enzyme elevations, which have been reported with orally administered PI3K inhibitors. The intravenous route of administration and intermittent dosing schedule of copanlisib may support a favorable tolerability profile over continually administered oral alternatives. Ongoing studies of copanlisib in combination with rituximab and standard-of-care chemotherapy in patients with relapsed indolent lymphoma have the potential to support the use of copanlisib in the second-line setting, providing a much-needed additional therapeutic option in this underserved patient population

Mapping and Functional Characterisation of a CTCF-Dependent Insulator Element at the 3′ Border of the Murine Scl Transcriptional Domain

The Scl gene encodes a transcription factor essential for haematopoietic development. Scl transcription is regulated by a panel of cis-elements spread over 55 kb with the most distal 3′ element being located downstream of the neighbouring gene Map17, which is co-regulated with Scl in haematopoietic cells. The Scl/Map17 domain is flanked upstream by the ubiquitously expressed Sil gene and downstream by a cluster of Cyp genes active in liver, but the mechanisms responsible for delineating the domain boundaries remain unclear. Here we report identification of a DNaseI hypersensitive site at the 3′ end of the Scl/Map17 domain and 45 kb downstream of the Scl transcription start site. This element is located at the boundary of active and inactive chromatin, does not function as a classical tissue-specific enhancer, binds CTCF and is both necessary and sufficient for insulator function in haematopoietic cells in vitro. Moreover, in a transgenic reporter assay, tissue-specific expression of the Scl promoter in brain was increased by incorporation of 350 bp flanking fragments from the +45 element. Our data suggests that the +45 region functions as a boundary element that separates the Scl/Map17 and Cyp transcriptional domains, and raise the possibility that this element may be useful for improving tissue-specific expression of transgenic constructs

DNA Damage–Induced Bcl-x(L) Deamidation Is Mediated by NHE-1 Antiport Regulated Intracellular pH

The pro-survival protein Bcl-x(L) is critical for the resistance of tumour cells to DNA damage. We have previously demonstrated, using a mouse cancer model, that oncogenic tyrosine kinase inhibition of DNA damage–induced Bcl-x(L) deamidation tightly correlates with T cell transformation in vivo, although the pathway to Bcl-x(L) deamidation remains unknown and its functional consequences unclear. We show here that rBcl-x(L) deamidation generates an iso-Asp(52)/iso-Asp(66) species that is unable to sequester pro-apoptotic BH3-only proteins such as Bim and Puma. DNA damage in thymocytes results in increased expression of the NHE-1 Na/H antiport, an event both necessary and sufficient for subsequent intracellular alkalinisation, Bcl-x(L) deamidation, and apoptosis. In murine thymocytes and tumour cells expressing an oncogenic tyrosine kinase, this DNA damage–induced cascade is blocked. Enforced intracellular alkalinisation mimics the effects of DNA damage in murine tumour cells and human B-lineage chronic lymphocytic leukaemia cells, thereby causing Bcl-x(L) deamidation and increased apoptosis. Our results define a signalling pathway leading from DNA damage to up-regulation of the NHE-1 antiport, to intracellular alkalanisation to Bcl-x(L) deamidation, to apoptosis, representing the first example, to our knowledge, of how deamidation of internal asparagine residues can be regulated in a protein in vivo. Our findings also suggest novel approaches to cancer therapy

Advanced Hodgkin lymphoma in the East of England: a 10-year comparative analysis of outcomes for real-world patients treated with ABVD or escalated-BEACOPP, aged less than 60 years, compared with 5-year extended follow-up from the RATHL trial.

Treatment with ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) or escalated(e)-BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisolone) remains the international standard of care for advanced-stage classical Hodgkin lymphoma (HL). We performed a retrospective, multicentre analysis of 221 non-trial ("real-world") patients, aged 16-59 years, diagnosed with advanced-stage HL in the Anglia Cancer Network between 2004 and 2014, treated with ABVD or eBEACOPP, and compared outcomes with 1088 patients in the Response-Adjusted Therapy for Advanced Hodgkin Lymphoma (RATHL) trial, aged 18-59 years, with median follow-up of 87.0 and 69.5 months, respectively. Real-world ABVD patients (n=177) had highly similar 5-year progression-free survival (PFS) and overall survival (OS) compared with RATHL (PFS 79.2% vs 81.4%; OS 92.9% vs 95.2%), despite interim positron-emission tomography-computed tomography (PET/CT)-guided dose-escalation being predominantly restricted to trial patients. Real-world eBEACOPP patients (n=44) had superior PFS (95.5%) compared with real-world ABVD (HR 0.20, p=0.027) and RATHL (HR 0.21, p=0.015), and superior OS for higher-risk (international prognostic score ≥3 [IPS 3+]) patients compared with real-world IPS 3+ ABVD (100% vs 84.5%, p=0.045), but not IPS 3+ RATHL patients. Our data support a PFS, but not OS, advantage for patients with advanced-stage HL treated with eBEACOPP compared with ABVD and suggest higher-risk patients may benefit disproportionately from more intensive therapy. However, increased access to effective salvage therapies might minimise any OS benefit from reduced relapse rates after frontline therapy

Efficacy of bendamustine and rituximab as first salvage treatment in chronic lymphocytic leukemia and indirect comparison with ibrutinib: A GIMEMA, ERIC and UK CLL FORUM study

We performed an observational study on the efficacy of bendamustine and rituximab (BR) as first salvage regimen in chronic lymphocytic leukemia (CLL). In an intention-to-treat analysis including 237 patients, the median progression-free survival (PFS) was 25 months. The presence of del (17p), unmutated IGHV and advanced stage were associated with a shorter PFS at multivariate analysis. The median time-to-next treatment was 31.3 months. Front-line treatment with a chemoimmunotherapy regimen was the only predictive factor for a shorter time to next treatment at multivariate analysis. The median overall survival (OS) was 74.5 months. Advanced disease stage (i.e. Rai stage III-IV or Binet stage C) and resistant disease were the only parameters significantly associated with a shorter OS. Grade 3-5 infections were recorded in 6.3% of patients. A matched-adjusted indirect comparison with ibrutinib given second-line within Named Patient Programs in the United Kingdom and in Italy was carried out with OS as objective end point. When restricting the analysis to patients with intact 17p who had received chemoimmunotherapy in first line, there was no difference in OS between patients treated with ibrutinib (63% alive at 36 months) and patients treated with BR (74.4% alive at 36 months). BR is an efficacious first salvage regimen in CLL in a real-life population, including the elderly and unfit patients. BR and ibrutinib may be equally effective in terms of OS when used as first salvage treatment in patients without 17p deletion. (Registered at clinicaltrials.gov identifier: 02491398)

Ibrutinib for mantle cell lymphoma at first relapse: a United Kingdom real-world analysis of outcomes in 211 patients.

Funder: Janssen Pharmaceuticals; Id: http://dx.doi.org/10.13039/100008897Ibrutinib is an established treatment for relapsed/refractory (R/R) mantle cell lymphoma (MCL) and clinical trial data supports use at second line compared to later relapse. We aimed to investigate outcomes and tolerability for ibrutinib when given second line in a real-world setting. Our multicentre retrospective analysis included 211 R/R MCL patients, median age 73 years, receiving ibrutinib second-line within the United Kingdom's National Health Service. Overall response to ibrutinib was 69% (complete response 27%). The median progression-free survival (PFS) was 17·8 months (95% CI 13·1-22·2) and median overall survival (OS) 23·9 months (95% CI 15·0-32·8). Drug-related adverse event led to dose reduction in 10% of patients and discontinuation in 5%. In patients with progressive disease, accounting for 100 of 152 patients stopping ibrutinib, 43% received further systemic therapy. Post-ibrutinib rituximab, bendamustine and cytarabine (R-BAC) showed a trend toward improved survival compared to alternative systemic treatments (post-ibrutinib median OS 14·0 months, 95% CI 8·1-19·8, vs. 3·6 months, 95% CI 2·6-4·5, P = 0·06). Our study confirms the clinical benefit and good tolerability of ibrutinib at first relapse in a real-world population. Patients progressing on ibrutinib had limited survival but outcomes with R-BAC in select patients were promising

Relapsed mantle cell lymphoma presenting with lactic acidosis and hypoglycemia: A case report

Lactic acidosis and hypoglycemia are rare presentations of malignancy with a poor prognosis. We present the case of a mantle cell lymphoma patient who relapsed with lactic acidosis and hypoglycemia. Although blood glucose, pH, and lactate normalized following chemotherapy and intensive care support, the patient died from ventilator‐associated pneumonia

Relapsed mantle cell lymphoma presenting with lactic acidosis and hypoglycemia: A case report.

Lactic acidosis and hypoglycemia are rare presentations of malignancy with a poor prognosis. We present the case of a mantle cell lymphoma patient who relapsed with lactic acidosis and hypoglycemia. Although blood glucose, pH, and lactate normalized following chemotherapy and intensive care support, the patient died from ventilator-associated pneumonia