Mechanism of branching morphogenesis inspired by diatom silica formation

The silica-based cell walls of diatoms are prime examples of genetically controlled, species-specific mineral architectures. The physical principles underlying morphogenesis of their hierarchically structured silica patterns are not understood, yet such insight could indicate novel routes toward synthesizing functional inorganic materials. Recent advances in imaging nascent diatom silica allow rationalizing possible mechanisms of their pattern formation. Here, we combine theory and experiments on the model diatom Thalassiosira pseudonana to put forward a minimal model of branched rib patterns-a fundamental feature of the silica cell wall. We quantitatively recapitulate the time course of rib pattern morphogenesis by accounting for silica biochemistry with autocatalytic formation of diffusible silica precursors followed by conversion into solid silica. We propose that silica deposition releases an inhibitor that slows down up-stream precursor conversion, thereby implementing a self-replicating reaction-diffusion system different from a classical Turing mechanism. The proposed mechanism highlights the role of geometrical cues for guided self-organization, rationalizing the instructive role for the single initial pattern seed known as the primary silicification site. The mechanism of branching morphogenesis that we characterize here is possibly generic and may apply also in other biological systems.

Artificial intelligence methods to estimate overall mortality and non-relapse mortality following allogeneic HCT in the modern era: an EBMT-TCWP study

Allogeneic haematopoietic cell transplantation (alloHCT) has curative potential counterbalanced by its toxicity. Prognostic scores fail to include current era patients and alternative donors. We examined adult patients from the EBMT registry who underwent alloHCT between 2010 and 2019 for oncohaematological disease. Our primary objective was to develop a new prognostic score for overall mortality (OM), with a secondary objective of predicting non-relapse mortality (NRM) using the OM score. AI techniques were employed. The model for OM was trained, optimized, and validated using 70%, 15%, and 15% of the data set, respectively. The top models, "gradient boosting" for OM (AUC = 0.64) and "elasticnet" for NRM (AUC = 0.62), were selected. The analysis included 33,927 patients. In the final prognostic model, patients with the lowest score had a 2-year OM and NRM of 18 and 13%, respectively, while those with the highest score had a 2-year OM and NRM of 82 and 93%, respectively. The results were consistent in the subset of the haploidentical cohort (n = 4386). Our score effectively stratifies the risk of OM and NRM in the current era but do not significantly improve mortality prediction. Future prognostic scores can benefit from identifying biological or dynamic markers post alloHCT.

Diatom adhesive trail proteins acquired by horizontal gene transfer from bacteria serve as primers for marine biofilm formation

Biofilm-forming benthic diatoms are key primary producers in coastal habitats, where they frequently dominate sunlit intertidal substrata. The development of gliding motility in raphid diatoms was a key molecular adaptation that contributed to their evolutionary success. However, the structure-function correlation between diatom adhesives utilized for gliding and their relationship to the extracellular matrix that constitutes the diatom biofilm is unknown. Here, we have used proteomics, immunolocalization, comparative genomics, phylogenetics and structural homology analysis to investigate the evolutionary history and function of diatom adhesive proteins. Our study identified eight proteins from the adhesive trails of Craspedostauros australis, of which four form a new protein family called Trailins that contain an enigmatic Choice-of-Anchor A (CAA) domain, which was acquired through horizontal gene transfer from bacteria. Notably, the CAA-domain shares a striking structural similarity with one of the most widespread domains found in ice-binding proteins (IPR021884). Our work offers new insights into the molecular basis for diatom biofilm formation, shedding light on the function and evolution of diatom adhesive proteins. This discovery suggests that there is a transition in the composition of biomolecules required for initial surface colonization and those utilized for 3D biofilm matrix formation.

Thalassiosira pseudonana (Cyclotella nana) (Hustedt) Hasle et Heimdal (Bacillariophyceae): A genetically tractable model organism for studying diatom biology, including biological silica formation

In 2004, Thalassiosira pseudonana was the first eukaryotic marine alga to have its genome sequenced. Since then, this species has quickly emerged as a valuable model species for investigating the molecular underpinnings of essentially all aspects of diatom life, particularly bio-morphogenesis of the cell wall. An important prerequisite for the model status of T. pseudonana is the ongoing development of increasingly precise tools to study the function of gene networks and their encoded proteins in vivo. Here, we briefly review the current toolbox for genetic manipulation, highlight specific examples of its application in studying diatom metabolism, and provide a peek into the role of diatoms in the emerging field of silica biotechnology.

On the role of cell surface associated, mucin-like glycoproteins in the pennate diatom Craspedostauros australis (Bacillariophyceae)

Diatoms are single-celled microalgae with silica-based cell walls (frustules) that are abundantly present in aquatic habitats, and form the basis of the food chain in many ecosystems. Many benthic diatoms have the remarkable ability to glide on all natural or man-made underwater surfaces using a carbohydrate- and protein-based adhesive to generate traction. Previously, three glycoproteins, termed FACs (Frustule Associated Components), have been identified from the common fouling diatom Craspedostauros australis and were implicated in surface adhesion through inhibition studies with a glycan-specific antibody. The polypeptide sequences of FACs remained unknown, and it was unresolved whether the FAC glycoproteins are indeed involved in adhesion, or whether this is achieved by different components sharing the same glycan epitope with FACs. Here we have determined the polypeptide sequences of FACs using peptide mapping by LC-MS/MS. Unexpectedly, FACs share the same polypeptide backbone (termed CaFAP1), which has a domain structure of alternating Cys-rich and Pro-Thr/Ser-rich regions reminiscent of the gel-forming mucins. By developing a genetic transformation system for C. australis, we were able to directly investigate the function of CaFAP1-based glycoproteins in vivo. GFP-tagging of CaFAP1 revealed that it constitutes a coat around all parts of the frustule and is not an integral component of the adhesive. CaFAP1-GFP producing transformants exhibited the same properties as wild type cells regarding surface adhesion and motility speed. Our results demonstrate that FAC glycoproteins are not involved in adhesion and motility, but might rather act as a lubricant to prevent fouling of the diatom surface.

A novel molecular signature identifies mixed subtypes in renal cell carcinoma with poor prognosis and independent response to immunotherapy

Background

Renal cell carcinoma (RCC) is a heterogeneous disease comprising histologically defined subtypes. For therapy selection, precise subtype identification and individualized prognosis are mandatory, but currently limited. Our aim was to refine subtyping and outcome prediction across main subtypes, assuming that a tumor is composed of molecular features present in distinct pathological subtypes.

Methods

Individual RCC samples were modeled as linear combination of the main subtypes (clear cell (ccRCC), papillary (pRCC), chromophobe (chRCC)) using computational gene expression deconvolution. The new molecular subtyping was compared with histological classification of RCC using the Cancer Genome Atlas (TCGA) cohort (n = 864; ccRCC: 512; pRCC: 287; chRCC: 65) as well as 92 independent histopathologically well-characterized RCC. Predicted continuous subtypes were correlated to cancer-specific survival (CSS) in the TCGA cohort and validated in 242 independent RCC. Association with treatment-related progression-free survival (PFS) was studied in the JAVELIN Renal 101 (n = 726) and IMmotion151 trials (n = 823). CSS and PFS were analyzed using the Kaplan–Meier and Cox regression analysis.

Results

One hundred seventy-four signature genes enabled reference-free molecular classification of individual RCC. We unambiguously assign tumors to either ccRCC, pRCC, or chRCC and uncover molecularly heterogeneous tumors (e.g., with ccRCC and pRCC features), which are at risk of worse outcome. Assigned proportions of molecular subtype-features significantly correlated with CSS (ccRCC (P = 4.1E − 10), pRCC (P = 6.5E − 10), chRCC (P = 8.6E − 06)) in TCGA. Translation into a numerical RCC-R(isk) score enabled prognosis in TCGA (P = 9.5E − 11). Survival modeling based on the RCC-R score compared to pathological categories was significantly improved (P = 3.6E − 11). The RCC-R score was validated in univariate (P = 3.2E − 05; HR = 3.02, 95% CI: 1.8–5.08) and multivariate analyses including clinicopathological factors (P = 0.018; HR = 2.14, 95% CI: 1.14–4.04). Heterogeneous PD-L1-positive RCC determined by molecular subtyping showed increased PFS with checkpoint inhibition versus sunitinib in the JAVELIN Renal 101 (P = 3.3E − 04; HR = 0.52, 95% CI: 0.36 − 0.75) and IMmotion151 trials (P = 0.047; HR = 0.69, 95% CI: 0.48 − 1). The prediction of PFS significantly benefits from classification into heterogeneous and unambiguous subtypes in both cohorts (P = 0.013 and P = 0.032).

Conclusion

Switching from categorical to continuous subtype classification across most frequent RCC subtypes enables outcome prediction and fosters personalized treatment strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13073-022-01105-y.

Shedding light on silica biomineralization by comparative analysis of the silica-associated proteomes from three diatom species

Morphogenesis of the intricate patterns of diatom silica cell walls is a protein-guided process, yet to date only very few such silica biomineralization proteins have been identified. Therefore, it is currently unknown whether all diatoms share conserved proteins of a basal silica forming machinery, and whether unique proteins are responsible for the morphogenesis of species-specific silica patterns. To answer these questions, we extracted proteins from the silica of three diatom species (Thalassiosira pseudonana, Thalassiosira oceanica, and Cyclotella cryptica) by complete demineralization of the cell walls. Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) analysis of the extracts identified 92 proteins that we name 'soluble silicome proteins' (SSPs). Surprisingly, no SSPs are common to all three species, and most SSPs showed very low similarity to one another in sequence alignments. In-depth bioinformatics analyses revealed that SSPs could be grouped into distinct classes based on short unconventional sequence motifs whose functions are yet unknown. The results from the in vivo localization of selected SSPs indicates that proteins, which lack sequence homology but share unconventional sequence motifs may exert similar functions in the morphogenesis of the diatom silica cell wall.

Managing hematological cancer patients during the COVID-19 pandemic: an ESMO-EHA Interdisciplinary Expert Consensus

BACKGROUND

The COVID-19 pandemic has created enormous challenges for the clinical management of patients with hematological malignancies (HMs), raising questions about the optimal care of this patient group.

METHODS

This consensus manuscript aims at discussing clinical evidence and providing expert advice on statements related to the management of HMs in the COVID-19 pandemic. For this purpose, an international consortium was established including a steering committee, which prepared six working packages addressing significant clinical questions from the COVID-19 diagnosis, treatment, and mitigation strategies to specific HMs management in the pandemic. During a virtual consensus meeting, including global experts and lead by the European Society for Medical Oncology and the European Hematology Association, statements were discussed and voted upon. When a consensus could not be reached, the panel revised statements to develop consensual clinical guidance.

RESULTS AND CONCLUSION

The expert panel agreed on 33 statements, reflecting a consensus, which will guide clinical decision making for patients with hematological neoplasms during the COVID-19 pandemic.

Management of adults and children receiving CAR T-cell therapy: 2021 best practice recommendations of the European Society for Blood and Marrow Transplantation (EBMT) and the Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association (EHA)

BACKGROUND

Several commercial and academic autologous chimeric antigen receptor T-cell (CAR-T) products targeting CD19 have been approved in Europe for relapsed/refractory B-cell acute lymphoblastic leukemia, high-grade B-cell lymphoma and mantle cell lymphoma. Products for other diseases such as multiple myeloma and follicular lymphoma are likely to be approved by the European Medicines Agency in the near future.

DESIGN

The European Society for Blood and Marrow Transplantation (EBMT)-Joint Accreditation Committee of ISCT and EBMT (JACIE) and the European Haematology Association collaborated to draft best practice recommendations based on the current literature to support health care professionals in delivering consistent, high-quality care in this rapidly moving field.

RESULTS

Thirty-six CAR-T experts (medical, nursing, pharmacy/laboratory) assembled to draft recommendations to cover all aspects of CAR-T patient care and supply chain management, from patient selection to long-term follow-up, post-authorisation safety surveillance and regulatory issues.

CONCLUSIONS

We provide practical, clinically relevant recommendations on the use of these high-cost, logistically complex therapies for haematologists/oncologists, nurses and other stakeholders including pharmacists and health sector administrators involved in the delivery of CAR-T in the clinic.

Metabolic syndrome and cardiovascular disease after haematopoietic cell transplantation (HCT) in adults: an EBMT cross-sectional non-interventional study

Metabolic syndrome (MetS) is associated with cardiovascular disease in the general population and is also a potential cardiovascular risk factor in survivors of haematopoietic cell transplantation (HCT). We report an EBMT cross-sectional, multi-centre, non-interventional study of 453 adult HCT patients surviving a minimum of 2 years post-transplant attending routine follow-up HCT and/or late effects clinics in 9 centres. The overall prevalence of MetS was 37.5% rising to 53% in patients >50 years of age at follow-up. There were no differences in rates of MetS between autologous and allogeneic HCT survivors, nor any association with graft-versus-host disease (GvHD) or current immunosuppressant therapy. Notably, there was a significantly higher occurrence of cardiovascular events (CVE, defined as cerebrovascular accident, coronary heart disease or peripheral vascular disease) in those with MetS than in those without MetS (26.7% versus 9%, p < 0.001, OR 3.69, 95% CI 2.09-6.54, p < 0.001), and, as expected, MetS and CVE were age-related. Unexpectedly, CVE were associated with occurrence of second malignancy. Screening for and management of MetS should be integrated within routine HCT long-term follow-up care for both allogeneic and autologous HCT survivors. Further research is warranted, including randomised controlled trials of interventional strategies and mechanistic studies of cardiovascular risk in HCT survivors.

Nocardia infections in hematopoietic cell transplant recipients: a multicenter international retrospective study of the Infectious Diseases Working Party (IDWP) of the European Society for Blood and Marrow Transplantation (EBMT)

BACKGROUND

Nocardiosis is rare after hematopoietic cell transplantation (HCT). Little is known regarding its presentation, management, and outcome in this population.

METHODS

In this retrospective international study, we reviewed nocardiosis episodes in HCT recipients (01.01.2000-31.12.2018; 135 transplant centers; 33 countries) and described their clinical, microbiological, radiological, and outcome characteristics.

RESULTS

We identified 81 nocardiosis episodes in 74 allo- and 7 auto-HCT recipients. Nocardiosis occurred at a median of 8 (IQR 4-18) months post-HCT. The most frequently involved organs were lungs (70/81; 86%) and brain (30/81; 37%); 29 (36%) patients were afebrile; 46/81 (57%) had disseminated infections. The most common lung imaging findings were consolidations (33/68; 49%) or nodules (32/68; 47%); and brain imaging findings were multiple brain abscesses (19/30; 63%). 10/30 (33%) patients with brain involvement lacked neurological symptoms. 14/48 (29%) patients were bacteremic. N. farcinica was the most common among molecularly identified species (27%, 12/44). Highest susceptibility rates were reported to linezolid 45/45 (100%), amikacin 56/57 (98%), trimethoprim-sulfamethoxazole 57/63 (90%), and imipenem 49/57 (86%).One-year and last follow-up (IQR: 4-42.5 months) all-cause mortality were 40% (32/81) and 52% (42/81), respectively. In the multivariable analysis, underlying disease not in complete remission (HR 2.81, 95%CI 1.32-5.95), and prior bacterial infection (HR 3.42, 95%CI 1.62-7.22) were associated with higher one-year all-cause mortality.

CONCLUSIONS

Nocardiosis is a late post-HCT infection usually manifesting as a pulmonary disease with frequent dissemination, brain infection and bacteremia. Brain imaging should be performed in HCT recipients with nocardiosis regardless of neurological symptoms. Overall mortality is high.

Pedobarography shows no differences in gait after talar fractures

BACKGROUND

Fractures of the talus often lead to permanent restrictions of the affected limb. Possible alterations after these fractures in gait have not been evaluated yet.

OBJECTIVE

To evaluate possible alterations of gait by pedybarography after talar fractures.

METHODS

We conducted a retrospective single-centre study at a level I trauma center. Twenty patients with operatively treated talar fractures were followed up. Objective and subjective function of the ankle was measured using range of motion, clinical scores and dynamic pedobarography (emed-M; Novel, Germany).

RESULTS

There were 11 talar neck and 9 talar body fractures. All patients received screw fixation. There was a significant reduction in range of motion. The outcome was moderate to satisfying and the severity of the injury correlated with the clinical outcome and the range of motion. The presence of posttraumatic arthritis and joint incongruity lead to a decreased function of ankle and subtalar joint and resulted in a worse clinical outcome. AVN rate was associated to initial displacement. Dynamic pedobarography showed no significant changes in gait pattern.

CONCLUSIONS

Fractures of the talus lead to dissatisfaction, pain and malfunction. However, a change in gait pattern could not be proved.

An intimate view into the silica deposition vesicles of diatoms

Diatoms are single-celled microalgae that produce silica-based cell walls with intricate nano- and micropatterns. Biogenesis of diatom biosilica is a bottom-up process that occurs in large intracellular compartments termed silica deposition vesicles (SDVs). Investigating the mechanisms of silica morphogenesis has so far been severely limited by the lack of methods for imaging the entire volume of an SDV with high spatial resolution during all stages of development. Here we have developed a method that allows for rapid identification and electron microscopy imaging of many different, full sized SDVs that are in the process of producing biosilica valves. This enabled visualizing the development of characteristic morphological biosilica features with unprecedented spatio-temporal resolution. During early to mid-term development, valve SDVs contained ~ 20 nm sized particles that were primarily associated with the radially expanding rib-like biosilica structures. The results from electron dispersive X-ray analysis suggests that the immature biosilica patterns are silica-organic composites. This supports the hypothesis that silica morphogenesis is dependent on organic biomolecules inside the SDV lumen.

[Current recommendations for the systemic treatment of metastatic renal cell carcinoma]

Numerous substances are available for the treatment of metastatic renal cell carcinoma (mRCC). Therefore, medical treatment of patients with mRCC has become a very complex subject. This review summarises clinical studies and typical side-effects of currently available agents that have been approved in Germany. The authors give suggestions for the use of these substances in the different therapy lines.

Identification of proteins in the adhesive trails of the diatom Amphora coffeaeformis

Throughout all kingdoms of life, a large number of adhesive biomolecules have evolved to allow organisms to adhere to surfaces underwater. Proteins play an important role in the adhesion of numerous marine invertebrates (e.g. mussels, sea stars, sea urchins) whereas much less is known about the biological adhesives from marine plants, including the diatoms. Diatoms are unicellular microalgae that together with bacteria dominate marine biofilms in sunlit habitats. In this study we present the first proteomics analyses of the diatom adhesive material isolated from the tenacious fouling species Amphora coffeaeformis. We identified 21 proteins, of which 13 are diatom-specific. Ten of these proteins share a conserved C-terminal domain, termed GDPH domain, which is widespread yet not ubiquitously present in all diatom classes. Immunofluorescence localization of a GDPH domain bearing protein (Ac629) as well as two other proteins identified in this study (Ac1442, Ac9617) demonstrated that these are components of the adhesive trails that are secreted by cells that glide on surfaces. This article is part of the theme issue 'Transdisciplinary approaches to the study of adhesion and adhesives in biological systems'.

Control of biosilica morphology and mechanical performance by the conserved diatom gene Silicanin-1

The species-specifically patterned biosilica cell walls of diatoms are paradigms for biological mineral morphogenesis and the evolution of lightweight materials with exceptional mechanical performance. Biosilica formation is a membrane-mediated process that occurs in intracellular compartments, termed silica deposition vesicles (SDVs). Silicanin-1 (Sin1) is a highly conserved protein of the SDV membrane, but its role in biosilica formation has remained elusive. Here we generate Sin1 knockout mutants of the diatom Thalassiosira pseudonana. Although the mutants grow normally, they exhibit reduced biosilica content and morphological aberrations, which drastically compromise the strength and stiffness of their cell walls. These results identify Sin1 as essential for the biogenesis of mechanically robust diatom cell walls, thus providing an explanation for the conservation of this gene throughout the diatom realm. This insight paves the way for genetic engineering of silica architectures with desired structures and mechanical performance.

Trends in patient outcome over the past two decades following allogeneic stem cell transplantation for acute myeloid leukaemia: an ALWP/EBMT analysis

BACKGROUND

Outcomes for patients with acute myeloid leukaemia (AML) undergoing allogeneic stem cell transplantation (allo-SCT) have significantly improved in recent years.

OBJECTIVES

To assess the incremental improvement of transplanted AML patients in the last two decades.

METHODS

Patients included in this analysis were adult AML patients who underwent allo-SCT from an HLA-matched sibling donor (MSD) or HLA-matched unrelated donor (MUD) in first remission. Patient outcomes were assessed between three cohorts according to the year of transplant (1993-2002, 2003-2007 and 2008-2012).

RESULTS

The analysis comprised a total of 20 187 patients of whom 4763 were transplanted between 1993 and 2002, 5835 in 2003 and 2007, and 9589 in 2008 and 2012. In multivariate analysis, leukaemia-free survival (LFS) rates were significantly improved in more recently transplanted patients compared to patients transplanted in 1993-2002 [Hazard ratio (HR) = 0.84, confidence interval (CI) 95%, 0.77-0.92; P = 0.003], a benefit which also extended to improved overall survival (OS; HR = 0.8, CI 95%, 0.73-0.89; P < 0.0001), and decreased nonrelapse mortality (NRM) rates (HR = 0.65, CI 95%, 0.56-0.75; P < 0.0001). Subset analysis revealed that in MSD, the rates of LFS, NRM and OS significantly improved in patients in the more recent cohort with similar results also seen in MUD. Finally, the incidence of acute graft-versus-host disease (GVHD) was significantly reduced leading to improved GVHD-free/relapse-free survival (GRFS) rates in more recently transplanted patients.

CONCLUSION

Outcome of allo-SCT for AML patients has markedly improved in the last two decades owing to decreased nonrelapse mortality and improved rates of leukaemia-free survival resulting in significantly longer survival.

Role of multiparametric magnetic resonance imaging for patients under active surveillance for prostate cancer: a systematic review with diagnostic meta-analysis

BACKGROUND

The use of multiparametric magnetic resonance imaging (mpMRI) in the setting of patients under active surveillance (AS) is promising. In this systematic-review we aimed to analyse the role of mpMRI in patients under AS.

METHODS

A comprehensive literature research for English-language original and review articles, recently published, was carried out using Medline, Scopus and Web of sciences databases until 30 October 2017. The following MeSH terms were used: 'active surveillance', 'prostate cancer', 'multiparametric magnetic resonance imaging'. A diagnostic meta-analysis was performed for 3.0 T mpMRI in predicting disease re-classification.

RESULTS

In total, 226 studies were selected after research and after removal of duplicates. After analysis on inclusion criteria, 43 studies were identified as eligible for this systematic review with a total of 6,605 patients. The timing of MRI during follow-up of AS differed from all studies like criteria for inclusion in the AS protocol. Overall, there was a low risk of bias across all studies. The diagnostic meta-analysis for 1.5 tesla showed a sensitivity of 0.60, negative predictive value (NPV) of 0.75 and a hierarchical summary receiving operating curve (HSROC) of 0.74 while for 3.0 tesla mpMRI a sensitivity of 0.81, a NPV of 0.78 and a HSROC of 0.83.

CONCLUSIONS

Overall, the available evidence suggests that both 1.5 or 3.0 Tesla mpMRI are a valid tool to monitor progression during AS follow-up, showing good accuracy capabilities in detecting PCa re-classification. However, the modality to better define what means 'disease progression' on mpMRI must be further evaluated.

What is the outcome in patients with acute leukaemia who survive severe acute graft-versus-host disease?

BACKGROUND

Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic haematopoietic stem cell transplantation (HSCT). With new promising therapies, survival may improve for severe aGVHD.

OBJECTIVES

We wanted to analyze the long-term outcome in patients who survive severe aGVHD.

METHODS

This study was a landmark analysis of 23 567 patients with acute Leukaemia who survived for more than 6 months after HSCT, 2002-2014. Patients alive after severe aGVHD (n = 1738) were compared to controls.

RESULTS

Patients with severe aGVHD had higher non-relapse mortality (NRM) and higher rate of extensive chronic GVHD (cGVHD) than the controls (P < 10^-5 ). The probability of relapse was significantly lower in the severe aGVHD group, but Leukaemia-free survival (LFS) and overall survival were significantly lower than for the controls (P < 10^-5 ). Five-year LFS in patients with severe aGVHD was 49%, as opposed to 61% in controls with no or mild GVHD and 59% in patients with moderate GVHD.

CONCLUSIONS

HSCT patients who survive severe aGVHD have higher risk of developing extensive cGVHD, a higher NRM, a lower relapse probability, and lower LFS than other HSCT patients. This study is a platform for outcome analysis in patients treated with novel therapies for acute GVHD.

[TKI 2.0 - changes in the medical treatment of renal cell carcinoma]

Only for renal cell carcinoma (RCC) in a local stage curative treatment option by surgical resection exists. For metastatic disease the 5‑year survival rate decreases radically. A factor that contributes to this is the low sensibility to radiation and chemotherapeutics. Since the approval of the tyrosine kinase inhibitors in 2006 effective drugs for the treatment of mRCC is available. The specific inhibition of the vascular-endothelial-growth (VEGF)-receptor and the "mammalian Target of Rapamycin" (mTOR) leads to a prolongation of the progression-free survival as well as the overall survival rate. For a long time, the current target therapy with TKI appeared to be exhausted, but since recently research has gone a step further. Thus, Cabozantinib and Lenvatinib in the combination with Everolimus have been approved for second-line therapy in mRCC. For the first time a clinical study demonstrated positive results for an adjuvant treatment with sunitinib in patients with a high-risk RCC. Furthermore, in april 2016 the immune checkpoint inhibitor Nivolumab was approved for second-line therapy in mRCC in Germany. The following report examines briefly the current therapeutic recommendations, new findings and drug approvals and ongoing clinical trials.

Silicanin-1 is a conserved diatom membrane protein involved in silica biomineralization

BACKGROUND

Biological mineral formation (biomineralization) proceeds in specialized compartments often bounded by a lipid bilayer membrane. Currently, the role of membranes in biomineralization is hardly understood.

RESULTS

Investigating biomineralization of SiO₂ (silica) in diatoms we identified Silicanin-1 (Sin1) as a conserved diatom membrane protein present in silica deposition vesicles (SDVs) of Thalassiosira pseudonana. Fluorescence microscopy of GFP-tagged Sin1 enabled, for the first time, to follow the intracellular locations of a biomineralization protein during silica biogenesis in vivo. The analysis revealed incorporation of the N-terminal domain of Sin1 into the biosilica via association with the organic matrix inside the SDVs. In vitro experiments showed that the recombinant N-terminal domain of Sin1 undergoes pH-triggered assembly into large clusters, and promotes silica formation by synergistic interaction with long-chain polyamines.

CONCLUSIONS

Sin1 is the first identified SDV transmembrane protein, and is highly conserved throughout the diatom realm, which suggests a fundamental role in the biomineralization of diatom silica. Through interaction with long-chain polyamines, Sin1 could serve as a molecular link by which the SDV membrane exerts control on the assembly of biosilica-forming organic matrices in the SDV lumen.

Impact of molecular residual disease post allografting in myelofibrosis patients

We screened 136 patients with myelofibrosis and a median age of 58 years who underwent allogeneic stem cell transplantation (AHSCT) for molecular residual disease for JAKV617F (n=101), thrombopoietin receptor gene (MPL) (n=4) or calreticulin (CALR) (n=31) mutation in peripheral blood on day +100 and +180 after AHSCT. After a median follow-up of 78 months, the 5-year estimated overall survival was 60% (95% confidence interval (CI): 50-70%) and the cumulative incidence of relapse at 5 years was 26% (95% CI: 18-34%) for the entire study population. The percentage of molecular clearance on day 100 was higher in CALR-mutated patients (92%) in comparison with MPL- (75%) and JAKV617F-mutated patients (67%). Patients with detectable mutation at day +100 or at day +180 had a significant higher risk of clinical relapse at 5 years than molecular-negative patients (62% vs 10%, P<0.001) and 70% vs 10%, P<0.001, respectively) irrespectively of the underlying mutation. In a multivariate analysis, high-risk diseases status (hazard ratio (HR) 2.5; 95% CI: 1.18-5.25, P=0.016) and detectable MRD at day 180 (HR 8.36, 95% CI: 2.76-25.30, P<0.001) were significant factors for a higher risk of relapse.

In search of the optimal platform for Post-Allogeneic SCT immunotherapy in relapsed multiple myeloma: a systematic review

Allogeneic stem cell transplantation (allo-SCT) has the potential to induce sustained remissions in patients with multiple myeloma (MM). Currently, allo-SCT is primarily performed in high-risk MM patients, most often in the setting of early relapse after first-line therapy with autologous SCT. However, the implementation of allo-SCT for MM is jeopardized by high treatment-related mortality (TRM) rates as well as high relapse rates. In this systematic review, we aimed to identify a safe allo-SCT strategy that has optimal 1-year results regarding mortality, relapse and severe GvHD, creating opportunities for post-transplantation strategies to maintain remissions in the high-risk group of relapsed MM patients. Eleven studies were included. Median PFS ranged from 5.2 to 36.8 months and OS was 13.0 to 63.0 months. The relapse related mortality at 1 year varied between 0 and 50% and TRM between 8 and 40%. Lowest GvHD incidences were reported for conditioning regimens with T-cell depletion using ATG or graft CD34+ selection. Similar strategies could lay the foundation for a post-transplant immune platform, this should be further evaluated in prospective clinical trials.

Risk factors for treatment failure after allogeneic transplantation of patients with CLL: a report from the European Society for Blood and Marrow Transplantation

For young patients with high-risk CLL, BTK-/PI3K-inhibitors or allogeneic stem cell transplantation (alloHCT) are considered. Patients with a low risk of non-relapse mortality (NRM) but a high risk of failure of targeted therapy may benefit most from alloHCT. We performed Cox regression analyses to identify risk factors for 2-year NRM and 5-year event-free survival (using EFS as a surrogate for long-term disease control) in a large, updated EBMT registry cohort (n= 694). For the whole cohort, 2-year NRM was 28% and 5-year EFS 37%. Higher age, lower performance status, unrelated donor type and unfavorable sex-mismatch had a significant adverse impact on 2-year NRM. Two-year NRM was calculated for good- and poor-risk reference patients. Predicted 2-year-NRM was 11 and 12% for male and female good-risk patients compared with 42 and 33% for male and female poor-risk patients. For 5-year EFS, age, performance status, prior autologous HCT, remission status and sex-mismatch had a significant impact, whereas del(17p) did not. The model-based prediction of 5-year EFS was 55% and 64%, respectively, for male and female good-risk patients. Good-risk transplant candidates with high-risk CLL and limited prognosis either on or after failure of targeted therapy should still be considered for alloHCT.

Impact of drug development on the use of stem cell transplantation: a report by the European Society for Blood and Marrow Transplantation (EBMT)

Hematopoietic stem cell transplantation (HSCT) is used with increasing frequency in Europe with 40 000 transplants reported in 2014. Transplant-related mortality remains high in allogeneic HSCT (10-20%); high-dose chemotherapy is toxic and demanding for patients. Drug development is accelerating and with limited toxicity of some targeted drugs may replace HSCT, whereas others may function as a 'bridge to transplant'. We analyzed HSCT reported to the activity survey for selected diseases in which major advances in drug development have been made. Tyrosine kinase inhibitors markedly changed the number of allogeneic HSCT in early CML. In myelodysplastic syndromes, hypomethylating agents show no effect on HSCT activity and Janus kinase inhibitors for myeloproliferative neoplasm appear to have only a temporary effect. For CLL autologous HSCT decreased after publication of trials showing improved PFS but no overall survival advantage and allogeneic rates are dropping after the introduction of Bruton kinase and PI3K Inhibitors. Whether these are 'game changers' as was imatinib for CML requires additional follow-up. For myeloma, proteasome inhibitors and new immunomodulatory drugs do not appear to impact transplant rates. Drug development data show different effects on HSCT use; highly effective drugs may replace HSCT, whereas other drugs may improve the patient's condition to allow for HSCT.

Prognostic pre-transplant factors in myelodysplastic syndromes primarily treated by high dose allogeneic hematopoietic stem cell transplantation: a retrospective study of the MDS subcommittee of the CMWP of the EBMT

Many pre-transplant factors are known to influence the outcome of allogeneic stem cell transplantation (SCT) treatment in myelodysplastic syndromes (MDS). However, patient cohorts are often heterogeneous by disease stage and treatment modalities, which complicates interpretation of the results. This study aimed to obtain a homogeneous patient cohort by including only de novo MDS patients who received upfront allogeneic SCT after standard high dose myelo-ablative conditioning. The effect of pre-transplant factors such as age, disease stage, transfusions, iron parameters and comorbidity on overall survival (OS), non-relapse mortality (NRM), and relapse incidence (RI) was evaluated in 201 patients. In this cohort, characterized by low comorbidity and a short interval between diagnosis and transplantation, NRM was the most determinant factor for survival after SCT (47 % after 2-year follow-up). WHO classification and transfusion burden were the only modalities with a significant impact on overall survival after SCT. Estimated hazard ratios (HR) showed a strongly increased risk of death, NRM and RI, in patients with a high transfusion-burden (HR 1.99; P = 0.006, HR of 1.89; P = 0.03 and HR 2.67; P = 0.03). The HR's for ferritin level and comorbidity were not significantly increased.

PSCD Domains of Pleuralin-1 from the Diatom Cylindrotheca fusiformis: NMR Structures and Interactions with Other Biosilica-Associated Proteins

Diatoms are eukaryotic unicellular algae characterized by silica cell walls and associated with three unique protein families, the pleuralins, frustulins, and silaffins. The NMR structure of the PSCD4 domain of pleuralin-1 from Cylindrotheca fusiformis contains only three short helical elements and is stabilized by five unique disulfide bridges. PSCD4 contains two binding sites for Ca(2+) ions with millimolar affinity. NMR-based interaction studies show an interaction of the domain with native silaffin-1A as well as with α-frustulins. The interaction sites of the two proteins mapped on the PSCD4 structure are contiguous and show only a small overlap. A plausible functional role of pleuralin could be to bind simultaneously silaffin-1A located inside the cell wall and α-frustulin coating the cell wall, thus connecting the interfaces between hypotheca and epitheca at the girdle bands. Restrained molecular dynamics calculations suggest a bead-chain-like structure of the central part of pleuralin-1.

Hematopoietic stem cell transplantation in Europe 2014: more than 40 000 transplants annually

A record number of 40 829 hematopoietic stem cell transplantation (HSCT) in 36 469 patients (15 765 allogeneic (43%), 20 704 autologous (57%)) were reported by 656 centers in 47 countries to the 2014 survey. Trends include: continued growth in transplant activity, more so in Eastern European countries than in the west; a continued increase in the use of haploidentical family donors (by 25%) and slower growth for unrelated donor HSCT. The use of cord blood as a stem cell source has decreased again in 2014. Main indications for HSCT were leukemias: 11 853 (33% 96% allogeneic); lymphoid neoplasias; 20 802 (57% 11% allogeneic); solid tumors; 1458 (4% 3% allogeneic) and non-malignant disorders; 2203 (6% 88% allogeneic). Changes in transplant activity include more allogeneic HSCT for AML in CR1, myeloproliferative neoplasm (MPN) and aplastic anemia and decreasing use in CLL; and more autologous HSCT for plasma cell disorders and in particular for amyloidosis. In addition, data on numbers of teams doing alternative donor transplants, allogeneic after autologous HSCT, autologous cord blood transplants are presented.

Biochemical Composition and Assembly of Biosilica-associated Insoluble Organic Matrices from the Diatom Thalassiosira pseudonana

The nano- and micropatterned biosilica cell walls of diatoms are remarkable examples of biological morphogenesis and possess highly interesting material properties. Only recently has it been demonstrated that biosilica-associated organic structures with specific nanopatterns (termed insoluble organic matrices) are general components of diatom biosilica. The model diatom Thalassiosira pseudonana contains three types of insoluble organic matrices: chitin meshworks, organic microrings, and organic microplates, the latter being described in the present study for the first time. To date, little is known about the molecular composition, intracellular assembly, and biological functions of organic matrices. Here we have performed structural and functional analyses of the organic microrings and organic microplates from T. pseudonana. Proteomics analysis yielded seven proteins of unknown function (termed SiMat proteins) together with five known silica biomineralization proteins (four cingulins and one silaffin). The location of SiMat1-GFP in the insoluble organic microrings and the similarity of tyrosine- and lysine-rich functional domains identifies this protein as a new member of the cingulin protein family. Mass spectrometric analysis indicates that most of the lysine residues of cingulins and the other insoluble organic matrix proteins are post-translationally modified by short polyamine groups, which are known to enhance the silica formation activity of proteins. Studies with recombinant cingulins (rCinY2 and rCinW2) demonstrate that acidic conditions (pH 5.5) trigger the assembly of mixed cingulin aggregates that have silica formation activity. Our results suggest an important role for cingulins in the biogenesis of organic microrings and support the hypothesis that this type of insoluble organic matrix functions in biosilica morphogenesis.

Ruxolitinib in corticosteroid-refractory graft-versus-host disease after allogeneic stem cell transplantation: a multicenter survey

Despite major improvements in allogeneic hematopoietic cell transplantation over the past decades, corticosteroid-refractory (SR) acute (a) and chronic (c) graft-versus-host disease (GVHD) cause high mortality. Preclinical evidence indicates the potent anti-inflammatory properties of the JAK1/2 inhibitor ruxolitinib. In this retrospective survey, 19 stem cell transplant centers in Europe and the United States reported outcome data from 95 patients who had received ruxolitinib as salvage therapy for SR-GVHD. Patients were classified as having SR-aGVHD (n=54, all grades III or IV) or SR-cGVHD (n=41, all moderate or severe). The median number of previous GVHD-therapies was 3 for both SR-aGVHD (1-7) and SR-cGVHD (1-10). The overall response rate was 81.5% (44/54) in SR-aGVHD including 25 complete responses (46.3%), while for SR-cGVHD the ORR was 85.4% (35/41). Of those patients responding to ruxolitinib, the rate of GVHD-relapse was 6.8% (3/44) and 5.7% (2/35) for SR-aGVHD and SR-cGVHD, respectively. The 6-month-survival was 79% (67.3-90.7%, 95% confidence interval (CI)) and 97.4% (92.3-100%, 95% CI) for SR-aGVHD and SR-cGVHD, respectively. Cytopenia and cytomegalovirus-reactivation were observed during ruxolitinib treatment in both SR-aGVHD (30/54, 55.6% and 18/54, 33.3%) and SR-cGVHD (7/41, 17.1% and 6/41, 14.6%) patients. Ruxolitinib may constitute a promising new treatment option for SR-aGVHD and SR-cGVHD that should be validated in a prospective trial.

Hematopoietic SCT in Europe 2013: recent trends in the use of alternative donors showing more haploidentical donors but fewer cord blood transplants

A record number of 39,209 HSCT in 34,809 patients (14,950 allogeneic (43%) and 19,859 autologous (57%)) were reported by 658 centers in 48 countries to the 2013 survey. Trends include: more growth in allogeneic than in autologous HSCT, increasing use of sibling and unrelated donors and a pronounced increase in haploidentical family donors when compared with cord blood donors for those patients without a matched related or unrelated donor. Main indications were leukemias, 11,190 (32%; 96% allogeneic); lymphoid neoplasias, 19,958 (57%; 11% allogeneic); solid tumors, 1543 (4%; 4% allogeneic); and nonmalignant disorders, 1975 (6%; 91% allogeneic). In patients without a matched sibling or unrelated donor, alternative donors are used. Since 2010 there has been a marked increase of 96% in the number of transplants performed from haploidentical relatives (802 in 2010 to 1571 in 2013), whereas the number of unrelated cord blood transplants has slightly decreased (789 in 2010 to 666 in 2013). The use of donor type varies greatly throughout Europe.

Indications for allo- and auto-SCT for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2015

This is the sixth special report that the European Society for Blood and Marrow Transplantation regularly publishes on the current practice and indications for haematopoietic SCT for haematological diseases, solid tumours and immune disorders in Europe. Major changes have occurred in the field of haematopoietic SCT over the last years. Cord blood units as well as haploidentical donors have been increasingly used as stem cell sources for allo-SCT, thus, augmenting the possibility of finding a suitable donor for a patient. Continuous refinement of conditioning strategies has also expanded not only the number of potential indications but also has permitted consideration of older patients or those with co-morbidity for a transplant. There is accumulating evidence of the role of haematopoietic SCT in non-haematological disorders such as autoimmune diseases. On the other hand, the advent of new drugs and very effective targeted therapy has challenged the role of SCT in some instances or at least, modified its position in the treatment armamentarium of a given patient. An updated report with revised tables and operating definitions is presented.

Allogeneic hematopoietic stem cell transplantation in solid organ transplant recipients: a retrospective, multicenter study of the EBMT

We conducted a questionnaire survey of the 565 European Society for Blood and Marrow Transplantation centers to analyze the outcome of allogeneic hematopoietic stem cell transplantation (alloSCT) in recipients of solid organ transplantation (SOT). We investigated 28 patients with malignant (N = 22) or nonmalignant diseases (N = 6), who underwent 31 alloSCT procedures: 12 after kidney, 13 after liver and 3 after heart transplantation. The incidence of solid organ graft failure at 60 months after first alloSCT was 33% (95% confidence interval [CI], 16-51%) for all patients, 15% (95% CI, 2-40%) for liver recipients and 50% (95% CI, 19-75%) for kidney recipients (p = 0.06). The relapse rate after alloSCT (22%) was low following transplantation for malignant disorders, despite advanced stages of malignancy. Overall survival at 60 months after first alloSCT was 40% (95% CI, 19-60%) for all patients, 51% (95% CI, 16-86%) for liver recipients and 42% (95% CI, 14-70%) for kidney recipients (p = 0.39). In summary, we show that selected SOT recipients suffering from hematologic disorders may benefit from alloSCT and experience enhanced long-term survival without loss of organ function.