Germinal centers in human lymph nodes contain reactivated memory B cells

To reveal migration trails of antigen-responsive B cells in lymphoid tissue, we analyzed immunoglobulin (Ig)M-VH and IgG-VH transcripts of germinal center (GC) samples microdissected from three reactive human lymph nodes. Single B cell clones were found in multiple GCs, one clone even in as many as 19 GCs. In several GCs, IgM and IgG variants of the same clonal origin were identified. The offspring of individual hypermutated IgG memory clones were traced in multiple GCs, indicating repeated engagement of memory B cells in GC reactions. These findings imply that recurring somatic hypermutation progressively drives the Ig repertoire of memory B cells to higher affinities and infer that transforming genetic hits in non-Ig genes during lymphomagenesis do not have to arise during a single GC passage, but can be collected during successive recall responses

Comprehensive analysis of published phase I/II clinical trials between 1990-2010 in osteosarcoma and Ewing sarcoma confirms limited outcomes and need for translational investment

BACKGROUND: High grade primary bone sarcomas are rare cancers that affect mostly children and young adults. Osteosarcoma and Ewing sarcoma are the most common histological subtypes in this age group, with current multimodality treatment strategies achieving 55-70% overall survival. As there remains an urgent need to develop new therapeutic interventions, we have reviewed published phase I/II trials that have been reported for osteosarcoma and Ewing sarcoma in the last twenty years.RESULTS: We conducted a literature search for clinical trials between 1990 and 2010, either for trials enrolling bone sarcoma patients as part of a general sarcoma indication or trials specifically in osteosarcoma and Ewing sarcoma. We identified 42 clinical trials that fulfilled our search criteria for general sarcoma that enrolled these patient groups, and eight and twenty specific trials for Ewing and osteosarcoma patients, respectively. For the phase I trials which enrolled different tumour types our results were incomplete, because the sarcoma patients were not mentioned in the PubMed abstract. A total of 3,736 sarcoma patients were included in these trials over this period, 1,114 for osteosarcoma and 1,263 for Ewing sarcoma. As a proportion of the worldwide disease burden over this period, these numbers reflect a very small percentage of the potential patient recruitment, approximately 0.6% for Ewing sarcoma and 0.2% for osteosarcoma. However, these data show an increase in recent activity overall and suggest there is still much room for improvement in the current trial development structures.CONCLUSION: Lack of resources and commercial investment will inevitably limit opportunity to develop sufficiently rapid improvements in clinical outcomes. International collaboration exists in many well founded co-operative groups for phase III trials, but progress may be more effective if there were also more investment of molecular and translational research into disease focused phase I/II clinical trials. Examples of new models for early translational and early phase trial collaboration include the European based EuroBoNeT network, the Sarcoma Alliance for Research through Collaboration network (SARC) and the new European collaborative translational trial network, EuroSarc.</p

Recurrent postmenopausal bleeding:Pathological findings and predictive factors. A multicenter, prospective, observational study

Introduction: Recurrent postmenopausal bleeding (PMB) occurs in 6%–25% of postmenopausal women who have experienced a previous episode of PMB. The question of whether recurrent PMB leads to a higher risk of endometrial cancer (EC) in comparison to a single episode of PMB is, however, controversial. Furthermore, little is known about predictive factors for recurrent PMB. Material and Methods: A multicenter prospective cohort study was conducted over a 5-year period in four hospitals in the Netherlands. Women with PMB undergoing endometrial sampling and aged 40 years and older were included. Occurrence of recurrent PMB was retrospectively determined. Primary outcomes included (1) the incidence of recurrent PMB and (2) differences in pathological findings between patients with a single episode vs recurrent PMB. Secondary outcomes included (1) the association between diagnosis of benign polyps at first PMB and pathological findings at recurrent PMB and (2) factors predictive for recurrent PMB. Results: A total of 437 women with PMB were included, of whom 360 were at risk of recurrent PMB. With a median follow-up of 61 months (IQR (Interquartile range) 44–73), 26.4% experienced recurrent PMB. Patients with recurrent PMB were more often diagnosed with benign polyps (34.7% vs. 25.1%, p-value 0.015) and less frequently with a malignancy (5.3% vs. 17.8%, p-value 0.015), compared to patients with a single episode of PMB. Benign polyps at initial PMB were not associated with a (pre)malignancy at recurrence (OR 4.16, 95% CI 0.75–23.03). Predictive factors for recurrent PMB included use of hormone replacement therapy (HRT) (OR 3.32, 95% CI 1.64–6.72), and benign polyps at initial PMB (OR 1.80, 95% CI 1.07–3.04). Conclusions: Recurrent PMB is common in women with a previous episode of PMB. Compared to patients with a single episode of PMB, patients with recurrent PMB and benign histological outcomes at accurate workup during their first episode were less often diagnosed with malignancies and more frequently with benign polyps. Benign polyps at first PMB are predictive for recurrent PMB, but not for a higher risk of (pre)malignancy.</p

Lung adenocarcinoma promotion by air pollutants

A complete understanding of how exposure to environmental substances promotes cancer formation is lacking. More than 70 years ago, tumorigenesis was proposed to occur in a two-step process: an initiating step that induces mutations in healthy cells, followed by a promoter step that triggers cancer development1. Here we propose that environmental particulate matter measuring ≤2.5 μm (PM2.5), known to be associated with lung cancer risk, promotes lung cancer by acting on cells that harbour pre-existing oncogenic mutations in healthy lung tissue. Focusing on EGFR-driven lung cancer, which is more common in never-smokers or light smokers, we found a significant association between PM2.5 levels and the incidence of lung cancer for 32,957 EGFR-driven lung cancer cases in four within-country cohorts. Functional mouse models revealed that air pollutants cause an influx of macrophages into the lung and release of interleukin-1β. This process results in a progenitor-like cell state within EGFR mutant lung alveolar type II epithelial cells that fuels tumorigenesis. Ultradeep mutational profiling of histologically normal lung tissue from 295 individuals across 3 clinical cohorts revealed oncogenic EGFR and KRAS driver mutations in 18% and 53% of healthy tissue samples, respectively. These findings collectively support a tumour-promoting role for PM2.5 air pollutants and provide impetus for public health policy initiatives to address air pollution to reduce disease burden

Clinical features of Ewing and chondrosarcoma

Ewing and chondrosaroma are two forms of primary bone cancer. The few clinical studies that are published in recent decades show disappointing results. With a 5 year survival of 10% for inoperable Ewing sarcoma and 2% for inoperable chondrosarcoma patients the outcome is poor. If a patient has not responded to standard treatment, they are often treated with combinations based on expert opinion of the treating physician. These treatment combinations have not been investigated in studies because of the small patient numbers which makes starting a study very difficult and time-consuming. One combination is of the chemotherapeutic agents etoposide with carboplatin or cisplatin. Analysis of the survival data of patients treated with these combinations shows that they are comparable to other standard treatment options. New non-chemotherapy treatment options are currently being investigated. Examples are the IGF-1R and PARP route. The current knowledge of both routes shows that disregulation causes malignant transformation and / or disease progression. Inhibition of these routes is therefore a possible treatment. In clinical studies, the results are not positive for all patients. This is due to incorrect patient selection and not being tested in combination with already used treatments.LUMC / Geneeskund

PanobinostatA Potential Treatment for Metastasized Ewing Sarcoma? A Case Report

Molecular tumour pathology - and tumour geneticsMTG

Ewing sarcoma: The clinical relevance of the insulin-like growth factor 1 and the poly-ADP-ribose-polymerase pathway

MTG6Molecular tumour pathology - and tumour genetic

Inhibition of Bcl-2 family members sensitizes mesenchymal chondrosarcoma to conventional chemotherapy: report on a novel mesenchymal chondrosarcoma cell line

Molecular tumour pathology - and tumour geneticsMTG

Chlamydia psittaci-negative ocular adnexal marginal zone B-cell lymphomas have biased v H 4-34 immunoglobulin gene expression and proliferate in a distinct inflammatory environment

Ocular adnexal marginal zone B-cell lymphomas (OAMZLs) arise in the connective tissues of the orbit or in the mucosa-associated lymphoid tissue of the conjunctiva. Here, we present the immunological and genetic analyses of 20 primary Chlamydia psittaci (Cp)-negative OAMZLs. Analysis of the immunoglobulin variable heavy chain (IgV H) gene usage demonstrated a significant preference for V H 4-34. A combined analysis across all previously published OAMZLs confirmed that this is a general feature of OAMZL, in particular of the Cp-negative group. Our series of OAMZLs did not express the characteristic rheumatoid factor V H DJ H rearrangements that were previously found in salivary gland-and gastric-marginal zone B-cell lymphomas (MZBCLs). We did not detect the MZBCL-specific chromosomal translocations, t(11;18) API2-MALT1 (mucosa-associated lymphoid tissue1) and t(14;18) IgH/MALT1. Two cases contained a premature stop codon in the A20 gene (TNFAIP3) and one case harbored the activating MYD88 hotspot mutation L265P. Variable nuclear expression of BCL10, NFB1 (p50) and NFB2 (p52) suggests that other additional genetic abnormalities affecting the NFB pathway exist within this group of lymphomas. OAMZL showed variable expression of the chemokine receptor CXCR3 and integrin α4Β7 by the tumor B cells, and low interferon-γ and interlukin-4 mRNA levels in the tissue, indicative of an inflammatory environment with features in between those previously found in cutaneous and other extranodal MZBCL. The strongly biased usage of V H 4-34 in Cp-negative OAMZLs suggests involvement of a particular stimulatory (auto-) antigen in their development

Outcomes from a mechanistic biomarker multi-arm and randomised study of liposomal MTP-PE (Mifamurtide) in metastatic and/or recurrent osteosarcoma (EuroSarc-Memos trial)

The phase III clinical study of adjuvant liposomal muramyl tripeptide (MTP-PE) in resected high-grade osteosarcoma (OS) documented positive results that have been translated into regulatory approval, supporting initial promise for innate immune therapies in OS. There remains, however, no new approved treatment such as MTP-PE for either metastatic or recurrent OS. Whilst the addition of different agents, including liposomal MTP-PE, to surgery for metastatic or recurrent high-grade osteosarcoma has tried to improve response rates, a mechanistic hiatus exists in terms of a detailed understanding the therapeutic strategies required in advanced disease. Here we report a Bayesian designed multi-arm, multi-centre, open-label phase II study with randomisation in patients with metastatic and/or recurrent OS, designed to investigate how patients with OS might respond to liposomal MTP-PE, either given alone or in combination with ifosfamide. Despite the trial closing because of poor recruitment within the allocated funding period, with no objective responses in eight patients, we report the design and feasibility outcomes for patients registered into the trial. We demonstrate the feasibility of the Bayesian design, European collaboration, tissue collection with genomic analysis and serum cytokine characterisation. Further mechanistic investigation of liposomal MTP-PE alone and in combination with other agents remains warranted in metastatic OS