Emerging organoid-immune co-culture models for cancer research: from oncoimmunology to personalized immunotherapies

In the past decade, treatments targeting the immune system have revolutionized the cancer treatment field. Therapies such as immune checkpoint inhibitors have been approved as first-line treatment in a variety of solid tumors such as melanoma and non-small cell lung cancer while other therapies, for instance, chimeric antigen receptor (CAR) lymphocyte transfer therapies, are still in development. Although promising results are obtained in a small subset of patients, overall clinical efficacy of most immunotherapeutics is limited due to intertumoral heterogeneity and therapy resistance. Therefore, prediction of patient-specific responses would be of great value for efficient use of costly immunotherapeutic drugs as well as better outcomes. Because many immunotherapeutics operate by enhancing the interaction and/or recognition of malignant target cells by T cells, in vitro cultures using the combination of these cells derived from the same patient hold great promise to predict drug efficacy in a personalized fashion. The use of two-dimensional cancer cell lines for such cultures is unreliable due to altered phenotypical behavior of cells when compared with the in vivo situation. Three-dimensional tumor-derived organoids, better mimic in vivo tissue and are deemed a more realistic approach to study the complex tumor-immune interactions. In this review, we present an overview of the development of patient-specific tumor organoid-immune co-culture models to study the tumor-specific immune interactions and their possible therapeutic infringement. We also discuss applications of these models which advance personalized therapy efficacy and understanding the tumor microenvironment such as: (1) Screening for efficacy of immune checkpoint inhibition and CAR therapy screening in a personalized manner. (2) Generation of tumor reactive lymphocytes for adoptive cell transfer therapies. (3) Studying tumor-immune interactions to detect cell-specific roles in tumor progression and remission. Overall, these onco-immune co-cultures might hold a promising future toward developing patient-specific therapeutic approaches as well as increase our understanding of tumor-immune interactions.

Global survival trends for brain tumors, by histology: analysis of individual records for 556,237 adults diagnosed in 59 countries during 2000-2014 (CONCORD-3)

BACKGROUND

Survival is a key metric of the effectiveness of a health system in managing cancer. We set out to provide a comprehensive examination of worldwide variation and trends in survival from brain tumors in adults, by histology.

METHODS

We analyzed individual data for adults (15-99 years) diagnosed with a brain tumor (ICD-O-3 topography code C71) during 2000-2014, regardless of tumor behavior. Data underwent a 3-phase quality control as part of CONCORD-3. We estimated net survival for 11 histology groups, using the unbiased nonparametric Pohar Perme estimator.

RESULTS

The study included 556,237 adults. In 2010-2014, the global range in age-standardized 5-year net survival for the most common sub-types was broad: in the range 20%-38% for diffuse and anaplastic astrocytoma, from 4% to 17% for glioblastoma, and between 32% and 69% for oligodendroglioma. For patients with glioblastoma, the largest gains in survival occurred between 2000-2004 and 2005-2009. These improvements were more noticeable among adults diagnosed aged 40-70 years than among younger adults.

CONCLUSIONS

To the best of our knowledge, this study provides the largest account to date of global trends in population-based survival for brain tumors by histology in adults. We have highlighted remarkable gains in 5-year survival from glioblastoma since 2005, providing large-scale empirical evidence on the uptake of chemoradiation at population level. Worldwide, survival improvements have been extensive, but some countries still lag behind. Our findings may help clinicians involved in national and international tumor pathway boards to promote initiatives aimed at more extensive implementation of clinical guidelines.

P-732 Definitions and diagnostic criteria for unexplained infertility (UI) – a systematic review

Study question

What are the various inclusion criteria for the definition of unexplained infertility used for recruitment to clinical trials, and is there homogeneity of these definitions?

Summary answer

There is a need to standardise the definition of unexplained infertility when recruiting for clinical trials to optimise interpretation of results and allow appropriate meta-analysis.

What is known already

Unexplained infertility (UI) is a diagnosis of exclusion. The pathology underlying this diagnosis is likely to include different subtle contributing factors.

Unfortunately there is no universally accepted definition of unexplained infertility. NICE in the UK, and ACOG/ASRM both have lists of recommended investigations but no specific minimum standards to define UI. Even the ICMART definition is ambiguous, describing ‘apparently normal’ ovarian function and ejaculate. This may lead to heterogeneity between inclusion criteria in relevant research studies. This introduces selection bias and renders meta-analysis of trial results less meaningful.

A single definition would improve the quality of research for this important diagnosis.

Study design, size, duration

A systematic review of primary research investigating definitions of unexplained infertility in humans. A thorough search of online databases Medline and Embase was performed from inception to November 2021. A bespoke Excel spreadsheet was used to collect data for baseline study characteristics and outcome data. Results are reported as percentages.

Participants/materials, setting, methods

The search strategy included all primary research on heterosexual couple unexplained infertility in human participants. Papers with specified inclusion criteria were included and no date or language restrictions were applied.

From 663 results, title and abstract screening identified 83 duplicates and 6 studies unsuitable for the review. A further 275 papers were excluded after full-text screening. 241 papers remained and their inclusion criteria recorded and analysed.

Main results and the role of chance

Only 35.7% of papers specified duration of infertility. Timescales varied from 1 year (46.5%), 2 years (39.5%) or 3 years (14%).

85% papers specified that semen analysis should be ‘normal’. Of these, 40% used the most recent WHO criteria. No other national or international criteria for grading semen analysis was identified.

90% studies required fallopian tube patency as an inclusion criteria. Of these, 65.4% specified bilateral patency. Methods for demonstrating patency included hysterosalpingogram (HSG) (15.7%), laparoscopy (18.4%), a combination of either (29.5%) or both (24.4%) of these or hystero-contrast-salpingography (0.9%). 11.5% papers did not specify an imaging modality.

48.5% included studies mentioned uterine cavity assessment, 65% of these using HSG to assess the cavity, other methods mentioned include ultrasound (26.5%) or hysteroscopy (15.4%).

Only 5.4% papers required either exclusion of or evidence of only minimal endometriosis

80.5% of included papers required evidence of regular ovulation. 58.7% used luteal serum progesterone levels, 41.2% required regular cycles (patient-reported) and 17.5% used basal body temperature pattern assessment. Other methods mentioned by a minority of papers include endometrial biopsy, ultrasound follicular tracking, serum and urinary luteinising hormone levels. 44% studies required normal endocrine profiles of which 66% measured prolactin and FSH and 50% measured thyroid function.

Limitations, reasons for caution

The strength of this study is that we included all primary research papers studying unexplained infertility with no time limitations. Included studies originated from across the world. This is a thorough representation of criteria used across all clinical trials for unexplained infertility.

Wider implications of the findings

Only 63/241 (26%) studies included duration of infertility, tubal patency, proof of ovulation and semen analysis in their inclusion criteria. This demonstrates the need for standardisation of the definition of unexplained infertility. If future research can apply the same inclusion criteria this will reduce selection bias and allow appropriate meta-analysis.

Trial registration number

NA

Quality of life with encorafenib plus cetuximab with or without binimetinib treatment in patients with BRAF V600E-mutant metastatic colorectal cancer: patient-reported outcomes from BEACON CRC

Background

In the BEACON CRC study (NCT02928224), encorafenib plus cetuximab with binimetinib {9.3 versus 5.9 months; hazard ratio (HR) [95% confidence interval (CI)]: 0.60 [0.47-0.75]} or without binimetinib [9.3 versus 5.9 months; HR (95% CI): 0.61 (0.48-0.77)] significantly improved overall survival (OS) compared with the previous standard of care (control) in patients with BRAF V600E metastatic colorectal cancer (mCRC). Quality of life (QoL) was a secondary endpoint, assessed using validated instruments.

Patients and methods

BEACON CRC was a randomized, open-label, phase III study comparing encorafenib plus cetuximab with or without binimetinib and the investigator’s choice of irinotecan plus cetuximab or FOLFIRI plus cetuximab (chemotherapy control) in patients with previously treated BRAF V600E mCRC. Patient-reported QoL assessments included the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC) and Functional Assessment of Cancer Therapy—Colorectal (FACT-C). The primary outcome for these tools was time to definitive 10% deterioration.

Results

Encorafenib plus cetuximab, both with and without binimetinib, was associated with longer median times to definitive 10% deterioration versus the control group in the EORTC Global Health Status scale [HR (95% CI): 0.65 (0.52-0.80) versus 0.61 (0.49-0.75), respectively] and the FACT-C functional well-being subscale [HR (95% CI): 0.62 (0.50-0.76) versus 0.58 (0.47-0.72), respectively]. Consistent results were observed across all subscales of the EORTC and FACT-C instruments. QoL was generally maintained during treatment for the global EORTC and FACT-C scales.

Conclusions

In addition to improving OS, encorafenib plus cetuximab with or without binimetinib delays QoL decline in previously treated patients with BRAF V600E-mutant mCRC.

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BEACON CRC compares encorafenib + cetuximab ± binimetinib to chemotherapy in previously treated BRAF V600E mCRC.

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Encorafenib + cetuximab had longer time to 10% deterioration versus control in QoL and functional well-being scales.

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Encorafenib + cetuximab ± binimetinib delays QoL decline in previously treated patients with BRAF V600E mCRC.

Management of adverse events from the treatment of encorafenib plus cetuximab for patients with BRAF V600E-mutant metastatic colorectal cancer: insights from the BEACON CRC study

Colorectal cancer is the second leading cause of cancer deaths worldwide, with a 5-year relative survival of 14% in patients with metastatic colorectal cancer (mCRC). Patients with BRAF V600E mutations, which occur in ∼10%-15% of patients with mCRC, have a poorer prognosis compared with those with wild-type BRAF tumours. The combination of the BRAF inhibitor encorafenib with the epidermal growth factor receptor inhibitor cetuximab currently represents the only chemotherapy-free targeted therapy approved in the USA and Europe for previously treated patients with BRAF V600E-mutated mCRC. As a class, BRAF inhibitors are associated with dermatologic, gastrointestinal, and renal events, as well as pyrexia and secondary skin malignancies. Adverse event (AE) profiles of specific BRAF inhibitors vary, however, and are affected by the specific agents given in combination. In patients with mCRC, commonly reported AEs of cetuximab monotherapy include infusion reactions and dermatologic toxicities. Data from the phase III BEACON CRC study indicate that the combination of encorafenib with cetuximab has a distinct safety profile. Here we review the most frequently reported AEs that occurred with this combination in BEACON CRC and best practices for managing and mitigating AEs that require more than standard supportive care.

Diagnosis and management of tropomyosin receptor kinase (TRK) fusion sarcomas: expert recommendations from the World Sarcoma Network

Sarcomas are a heterogeneous group of malignancies with mesenchymal lineage differentiation. The discovery of neurotrophic tyrosine receptor kinase (NTRK) gene fusions as tissue-agnostic oncogenic drivers has led to new personalized therapies for a subset of patients with sarcoma in the form of tropomyosin receptor kinase (TRK) inhibitors. NTRK gene rearrangements and fusion transcripts can be detected with different molecular pathology techniques, while TRK protein expression can be demonstrated with immunohistochemistry. The rarity and diagnostic complexity of NTRK gene fusions raise a number of questions and challenges for clinicians. To address these challenges, the World Sarcoma Network convened two meetings of expert adult oncologists and pathologists and subsequently developed this article to provide practical guidance on the management of patients with sarcoma harboring NTRK gene fusions. We propose a diagnostic strategy that considers disease stage and histologic and molecular subtypes to facilitate routine testing for TRK expression and subsequent testing for NTRK gene fusions.

Neutrophils and Neutrophil Extracellular Traps Drive Necroinflammation in COVID-19

The COVID-19 pandemic is progressing worldwide with an alarming death toll. There is an urgent need for novel therapeutic strategies to combat potentially fatal complications. Distinctive clinical features of severe COVID-19 include acute respiratory distress syndrome, neutrophilia, and cytokine storm, along with severe inflammatory response syndrome or sepsis. Here, we propose the putative role of enhanced neutrophil infiltration and the release of neutrophil extracellular traps, complement activation and vascular thrombosis during necroinflammation in COVID-19. Furthermore, we discuss how neutrophilic inflammation contributes to the higher mortality of COVID-19 in patients with underlying co-morbidities such as diabetes and cardiovascular diseases. This perspective highlights neutrophils as a putative target for the immunopathologic complications of severely ill COVID-19 patients. Development of the novel therapeutic strategies targeting neutrophils may help reduce the overall disease fatality rate of COVID-19.

Neutrophil Extracellular Traps (NETs) Take the Central Stage in Driving Autoimmune Responses

Following fifteen years of research, neutrophil extracellular traps (NETs) are widely reported in a large range of inflammatory infectious and non-infectious diseases. Cumulating evidences from in vitro, in vivo and clinical diagnostics suggest that NETs may play a crucial role in inflammation and autoimmunity in a variety of autoimmune diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) and anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV). Most likely, NETs contribute to breaking self-tolerance in autoimmune diseases in several ways. During this review, we discuss the current knowledge on how NETs could drive autoimmune responses. NETs can break self-tolerance by being a source of autoantigens for autoantibodies found in autoimmune diseases, such as anti-citrullinated protein antibodies (ACPAs) in RA, anti-dsDNA in SLE and anti-myeloperoxidase and anti-protein 3 in AAV. Moreover, NET components could accelerate the inflammatory response by mediating complement activation, acting as danger-associated molecular patterns (DAMPs) and inflammasome activators, for example. NETs also can activate other immune cells, such as B cells, antigen-presenting cells and T cells. Additionally, impaired clearance of NETs in autoimmune diseases prolongs the presence of active NETs and their components and, in this way, accelerate immune responses. NETs have not only been implicated as drivers of inflammation, but also are linked to resolution of inflammation. Therefore, NETs may be central regulators of inflammation and autoimmunity, serve as biomarkers, as well as promising targets for future therapeutics of inflammatory autoimmune diseases.

Mitochondria Permeability Transition versus Necroptosis in Oxalate-Induced AKI

BACKGROUND

Serum oxalate levels suddenly increase with certain dietary exposures or ethylene glycol poisoning and are a well known cause of AKI. Established contributors to oxalate crystal-induced renal necroinflammation include the NACHT, LRR and PYD domains-containing protein-3 (NLRP3) inflammasome and mixed lineage kinase domain-like (MLKL) protein-dependent tubule necroptosis. These studies examined the role of a novel form of necrosis triggered by altered mitochondrial function.

METHODS

To better understand the molecular pathophysiology of oxalate-induced AIK, we conducted in vitro studies in mouse and human kidney cells and in vivo studies in mice, including wild-type mice and knockout mice deficient in peptidylprolyl isomerase F (Ppif) or deficient in both Ppif and Mlkl.

RESULTS

Crystals of calcium oxalate, monosodium urate, or calcium pyrophosphate dihydrate, as well as silica microparticles, triggered cell necrosis involving PPIF-dependent mitochondrial permeability transition. This process involves crystal phagocytosis, lysosomal cathepsin leakage, and increased release of reactive oxygen species. Mice with acute oxalosis displayed calcium oxalate crystals inside distal tubular epithelial cells associated with mitochondrial changes characteristic of mitochondrial permeability transition. Mice lacking Ppif or Mlkl or given an inhibitor of mitochondrial permeability transition displayed attenuated oxalate-induced AKI. Dual genetic deletion of Ppif and Mlkl or pharmaceutical inhibition of necroptosis was partially redundant, implying interlinked roles of these two pathways of regulated necrosis in acute oxalosis. Similarly, inhibition of mitochondrial permeability transition suppressed crystal-induced cell death in primary human tubular epithelial cells. PPIF and phosphorylated MLKL localized to injured tubules in diagnostic human kidney biopsies of oxalosis-related AKI.

CONCLUSIONS

Mitochondrial permeability transition-related regulated necrosis and necroptosis both contribute to oxalate-induced AKI, identifying PPIF as a potential molecular target for renoprotective intervention.

Phase Ib study of atezolizumab combined with cobimetinib in patients with solid tumors

BACKGROUND

Preclinical evidence suggests that MEK inhibition promotes accumulation and survival of intratumoral tumor-specific T cells and can synergize with immune checkpoint inhibition. We investigated the safety and clinical activity of combining a MEK inhibitor, cobimetinib, and a programmed cell death 1 ligand 1 (PD-L1) inhibitor, atezolizumab, in patients with solid tumors.

PATIENTS AND METHODS

This phase I/Ib study treated PD-L1/PD-1-naive patients with solid tumors in a dose-escalation stage and then in multiple, indication-specific dose-expansion cohorts. In most patients, cobimetinib was dosed once daily orally for 21 days on, 7 days off. Atezolizumab was dosed at 800 mg intravenously every 2 weeks. The primary objectives were safety and tolerability. Secondary end points included objective response rate, progression-free survival, and overall survival.

RESULTS

Between 27 December 2013 and 9 May 2016, 152 patients were enrolled. As of 4 September 2017, 150 patients received ≥1 dose of atezolizumab, including 14 in the dose-escalation cohorts and 136 in the dose-expansion cohorts. Patients had metastatic colorectal cancer (mCRC; n = 84), melanoma (n = 22), non-small-cell lung cancer (NSCLC; n = 28), and other solid tumors (n = 16). The most common all-grade treatment-related adverse events (AEs) were diarrhea (67%), rash (48%), and fatigue (40%), similar to those with single-agent cobimetinib and atezolizumab. One (<1%) treatment-related grade 5 AE occurred (sepsis). Forty-five (30%) and 23 patients (15%) had AEs that led to discontinuation of cobimetinib and atezolizumab, respectively. Confirmed responses were observed in 7 of 84 patients (8%) with mCRC (6 responders were microsatellite low/stable, 1 was microsatellite instable), 9 of 22 patients (41%) with melanoma, and 5 of 28 patients (18%) with NSCLC. Clinical activity was independent of KRAS/BRAF status across diseases.

CONCLUSIONS

Atezolizumab plus cobimetinib had manageable safety and clinical activity irrespective of KRAS/BRAF status. Although potential synergistic activity was seen in mCRC, this was not confirmed in a subsequent phase III study.

CLINICALTRIALS.GOV IDENTIFIER

NCT01988896 (the investigators in the NCT01988896 study are listed in the supplementary Appendix, available at Annals of Oncology online).

To NET or not to NET:current opinions and state of the science regarding the formation of neutrophil extracellular traps

Since the discovery and definition of neutrophil extracellular traps (NETs) 14 years ago, numerous characteristics and physiological functions of NETs have been uncovered. Nowadays, the field continues to expand and novel mechanisms that orchestrate formation of NETs, their previously unknown properties, and novel implications in disease continue to emerge. The abundance of available data has also led to some confusion in the NET research community due to contradictory results and divergent scientific concepts, such as pro- and anti-inflammatory roles in pathologic conditions, demarcation from other forms of cell death, or the origin of the DNA that forms the NET scaffold. Here, we present prevailing concepts and state of the science in NET-related research and elaborate on open questions and areas of dispute.

Abstract PD1-06: A phase 1b dose-escalation and expansion study of the BCL-2 inhibitor venetoclax combined with tamoxifen in ER and BCL-2–positive metastatic breast cancer (MBC)

Background: Venetoclax, a potent and selective inhibitor of the survival protein BCL-2 (recently approved in CLL and in development in other hematopoietic malignancies), has yet to be evaluated in pts with solid tumors. BCL-2 is overexpressed in ˜85% of ER+ breast cancer. Pre-clinical findings using patient-derived xenograft breast tumor models suggest that venetoclax synergizes with endocrine therapy by increasing apoptosis. Here we report mBEP, an investigator-initiated phase 1b study of venetoclax with tamoxifen in 33 pts with ER+ (&gt;1%), BCL-2+ (&gt;10%, 2-3+ intensity) and HER2– MBC.

Methods: We conducted a 3+3 dose escalation study comprising cohorts receiving venetoclax 200, 400, 600 or 800 mg/d with tamoxifen 20 mg/d (continued until progression). The primary endpoint was to determine the maximum tolerated dose (MTD), define dose-limiting toxicities (DLTs) and identify the recommended phase 2 dose (RP2D). In a dose expansion phase (at the RP2D), secondary endpoints including safety and tolerability, response at 24 wks (RECIST v1.1), clinical benefit rate (CBR) and progression-free survival (PFS) were studied.

Results: In the escalation phase (n=15 pts), treatment was well tolerated with no DLTs or high-grade (Gd 3/4) adverse events observed, apart from asymptomatic on-target lymphopenia (Gd 3, 2/15 pts). MTD was not reached. The 800 mg/d dose was selected as the RP2D and the cohort expanded to include 24 pts with ≥24 wks follow up (range 24-105 wks). Fifteen pts had received prior regimens for MBC (median 3, range 1-9) that included tamoxifen in 5/15.

For the RP2D cohort (n=24), overall responses (OR) included 1 CR (4%) and 12 PR (50%), with 5 SD (21%), corresponding to a CBR of 75%. The 9 pts treated in the first line setting experienced a 78% OR (7/9 pts) and 11% SD (1/9 pts), equating to an 89% CBR. The data are immature for determining median PFS for the RP2D cohort (currently 40+ wks).

Treatment responses were pre-empted by metabolic responses (FDG-PET) at 4 wks (seen in 13/16 (81%) pts studied), and correlated with serial changes in circulating tumor DNA (ctDNA). Intriguingly, responses and clinical benefit were observed in pts with plasma-detected ESR1 mutations (4/10 and 7/10, respectively).

The most common treatment-related AEs (CTCAE v4.0) for all pts were lymphopenia in 29/33 (88%; 57% Gd 1-2, 30% Gd 3-4), neutropenia in 24/33 (73%; 67% Gd 1-2, 6% Gd 3), nausea in 22/33 (67%; all ≤Gd 2), anemia in 13/33 (39%; 33% Gd 1-2, 6% G3), thrombocytopenia in 11/33 (33%; all ≤Gd 2), vomiting in 11/33 (33%, all ≤Gd 2), diarrhea in 10/33 (30%; 24% Gd 1-2, 6% Gd 3), infection in 9/33 (27%; 18% Gd 2, 9% Gd 3) and fatigue in 7/33 (21%; all ≤Gd 2). There was one possible treatment-related SAE (infection).

Conclusions: In the first clinical study to evaluate venetoclax in a solid tumor, we demonstrate that combining venetoclax with endocrine therapy has a tolerable safety profile and elicits remarkable activity in ER+ and BCL-2+ MBC. These findings support further investigation of combination therapy for patients with BCL-2-positive breast cancer.

Sponsor: The Royal Melbourne Hospital (ACTRN12615000702516)

Citation Format: Lindeman GJ, Lok SW, Whittle JR, Siow ZR, Bergin AR, Dawson S-J, Desai J, Gray DH, Liew D, Mann GB, Murugasu A, Roberts AW, Rosenthal MA, Shackleton K, Sherman P, Silva MJ, Teh C, Travers A, Vaillant F, Visvader JE. A phase 1b dose-escalation and expansion study of the BCL-2 inhibitor venetoclax combined with tamoxifen in ER and BCL-2–positive metastatic breast cancer (MBC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD1-06.

CXCL12 blockade preferentially regenerates lost podocytes in cortical nephrons by targeting an intrinsic podocyte-progenitor feedback mechanism

Insufficient podocyte regeneration after injury is a central pathomechanism of glomerulosclerosis and chronic kidney disease. Podocytes constitutively secrete the chemokine CXCL12, which is known to regulate homing and activation of stem cells; hence we hypothesized a similar effect of CXCL12 on podocyte progenitors. CXCL12 blockade increased podocyte numbers and attenuated proteinuria in mice with Adriamycin-induced nephropathy. Similar studies in lineage-tracing mice revealed enhanced de novo podocyte formation from parietal epithelial cells in the setting of CXCL12 blockade. Super-resolution microscopy documented full integration of these progenitor-derived podocytes into the glomerular filtration barrier, interdigitating with tertiary foot processes of neighboring podocytes. Quantitative 3D analysis revealed that conventional 2D analysis underestimated the numbers of progenitor-derived podocytes. The 3D analysis also demonstrated differences between juxtamedullary and cortical nephrons in both progenitor endowment and Adriamycin-induced podocyte loss, with more robust podocyte regeneration in cortical nephrons with CXCL12 blockade. Finally, we found that delayed CXCL12 inhibition still had protective effects. In vitro studies found that CXCL12 inhibition uncoupled Notch signaling in podocyte progenitors. These data suggest that CXCL12-driven podocyte-progenitor feedback maintains progenitor quiescence during homeostasis, but also limits their intrinsic capacity to regenerate lost podocytes, especially in cortical nephrons. CXCL12 inhibition could be an innovative therapeutic strategy in glomerular disorders.

Gender differences in doxorubicin pharmacology for subjects with chemosensitive cancers of young adulthood

PURPOSE

For many cancers, adolescents and young adults (AYA) have worse outcomes than for children and adults. Many factors may contribute to the AYA survival gap, including differences in biology, therapeutic intent, and adherence to therapy. It has been observed that male AYAs have poorer outcomes than females. The purpose of this work was to test the proposition that gender-related pharmacologic factors may account for a component of the AYA survival gap.

PATIENTS AND METHODS

A prospective, multi-institutional pharmacologic study of 79 patients in total with chemosensitive cancers (Ewing sarcoma, osteosarcoma and Hodgkin lymphoma) was conducted, with conventional doxorubicin treatment. Pharmacokinetic data of 13 children, 40 AYAs and 13 adults were valid for analysis. Population pharmacokinetics models were developed for doxorubicin and its metabolite doxorubicinol based on the data created in this study. Consequently, model-based analysis was conducted to investigate the relevant topics.

RESULTS

The clearance of doxorubicinol (normalized to body surface area), the main active metabolite of doxorubicin, appears faster in male AYAs than female (p = 0.04, 95% CI 0.1-3.9 L/h). The exposure of doxorubicinol (normalized to dose) is lower in male AYA than female (p = 0.03, 95% CI - 0.005 to - 0.0002 h/L). These might be correlated to the observed difference on nadir neutrophil count between male AYA and female (p = 0.027, 95% CI 0.09-1.4).

CONCLUSION

Gender-related differences in doxorubicin pharmacology may account for worse outcomes for male AYAs with chemosensitive cancers compared to females. These findings may reduce the AYA survival gap compared to other age groups.

Release of syngnathia by anticlockwise rotation and mandibular advancement using bilateral alloplastic temporomandibular joint prostheses: a new approach

We describe a new approach to the planning of treatment and subsequent operation on a patient with syngnathia and severe mandibular retrognathism. To facilitate a large mandibular advancement we applied alloplastic temporomandibular joint (TMJ) prostheses to the coronoid processes after anticlockwise rotation of the mandible. To the best of our knowledge this is the first documented case of its kind.

Activated platelets induce MLKL-driven neutrophil necroptosis and release of neutrophil extracellular traps in venous thrombosis

Venous thromboembolic (VTE) disease, often manifesting as deep vein thrombosis or pulmonary embolism, involves clot formation consisting of blood cells and platelets locked in plasma protein and chromatin networks. The latter derives from neutrophil extracellular traps released by dying neutrophils; however, the molecular mechanisms of neutrophil death in VTE remains unknown. We speculated that mixed lineage kinase-like (MLKL)-driven neutrophil necroptosis contributes to VTE. Indeed, human inferior venous cava thrombus material stained positive for phosphorylated MLKL, the activated version of MLKL that executes necroptotic cell death. In mice, MLKL immunostaining showed co-localization of MLKL with citrullinated histone H3, a marker of neutrophil extracellular trap (NET) formation. These data provide indirect support for a role of MLKL-mediated necroptosis. As a functional proof, both the stabilizer of receptor-interacting protein kinase-1 (RIPK1) and necroptosis inhibitor necrostatin-1s as well as genetic deficiency of MLKL partially prevented clot formation upon inferior vena cava ligation in mice. In both experiments terminal deoxynucleotidyl transferase dUTP nick-end labeling, RIPK3, and citrullinated histone H3+ areas were markedly reduced within the remnant thrombus. In vitro, thrombin-activated platelets induced cell death and NET formation in human neutrophils, which was inhibited by necrostatin-1s treatment. Necrostatin-1s and necrosulfonamide also inhibited neutrophil-platelet aggregate formation induced by tumor necrosis factor-α but had no effect on platelet activation itself. We conclude that in VTE, activated platelets, and possibly other triggers, induce neutrophil necroptosis, a process contributing to clot formation by releasing chromatin in the extracellular space.

How Kidney Cell Death Induces Renal Necroinflammation

The nephrons of the kidney are independent functional units harboring cells of a low turnover during homeostasis. As such, physiological renal cell death is a rather rare event and dead cells are flushed away rapidly with the urinary flow. Renal cell necrosis occurs in acute kidney injuries such as thrombotic microangiopathies, necrotizing glomerulonephritis, or tubular necrosis. All of these are associated with intense intrarenal inflammation, which contributes to further renal cell loss, an autoamplifying process referred to as necroinflammation. But how does renal cell necrosis trigger inflammation? Here, we discuss the role of danger-associated molecular patterns (DAMPs), mitochondrial (mito)-DAMPs, and alarmins, as well as their respective pattern recognition receptors. The capacity of DAMPs and alarmins to trigger cytokine and chemokine release initiates the recruitment of leukocytes into the kidney that further amplify necroinflammation. Infiltrating neutrophils often undergo neutrophil extracellular trap formation associated with neutrophil death or necroptosis, which implies a release of histones, which act not only as DAMPs but also elicit direct cytotoxic effects on renal cells, namely endothelial cells. Proinflammatory macrophages and eventually cytotoxic T cells further drive kidney cell death and inflammation. Dissecting the molecular mechanisms of necroinflammation may help to identify the best therapeutic targets to limit nephron loss in kidney injury.

Phagocytosis of environmental or metabolic crystalline particles induces cytotoxicity by triggering necroptosis across a broad range of particle size and shape

In crystallopathies, crystals or crystalline particles of environmental and metabolic origin deposit within tissues, induce inflammation, injury and cell death and eventually lead to organ-failure. The NLRP3-inflammasome is involved in mediating crystalline particles-induced inflammation, but pathways leading to cell death are still unknown. Here, we have used broad range of intrinsic and extrinsic crystal- or crystalline particle-sizes and shapes, e.g. calcium phosphate, silica, titanium dioxide, cholesterol, calcium oxalate, and monosodium urate. As kidney is commonly affected by crystallopathies, we used human and murine renal tubular cells as a model system. We showed that all of the analysed crystalline particles induce caspase-independent cell death. Deficiency of MLKL, siRNA knockdown of RIPK3, or inhibitors of necroptosis signaling e.g. RIPK-1 inhibitor necrostatin-1s, RIPK3 inhibitor dabrafenib, and MLKL inhibitor necrosulfonamide, partially protected tubular cells from crystalline particles cytotoxicity. Furthermore, we identify phagocytosis of crystalline particles as an upstream event in their cytotoxicity since a phagocytosis inhibitor, cytochalasin D, prevented their cytotoxicity. Taken together, our data confirmed the involvement of necroptosis as one of the pathways leading to cell death in crystallopathies. Our data identified RIPK-1, RIPK3, and MLKL as molecular targets to limit tissue injury and organ failure in crystallopathies.

Particles of different sizes and shapes induce neutrophil necroptosis followed by the release of neutrophil extracellular trap-like chromatin

The human body is exposed to a wide range of particles of industrial, environmental or internal origin such as asbestos, alum, silica or crystals of urate, calcium phosphate, calcium oxalate, cystine or cholesterol. Phagocytic clearance of such particles involves neutrophils and macrophages. Here we report that neutrophils encountering such particles of diverse sizes and shapes undergo necrotic cell death, a process associated with the formation of neutrophil extracellular trap (NET)-like extracellular DNA. In human neutrophils receptor-interacting protein kinase (RIPK)-1 inhibition with necrostatin-1s or mixed lineage kinase domain-like (MLKL) inhibition with necrosulfonamide abrogated cell death and associated-neutrophil extracellular DNA release induced by all of the aforementioned particles. Similar results were obtained with Mlkl-deficient mice neutrophils for all particles in vitro. Furthermore, Mlkl-deficient mice lacked tophus formation upon injection of MSU crystals into subcutaneous air pouches. These findings imply that nano- or microparticle-induced neutrophil extracellular DNA release is the consequence of neutrophil necroptosis, a regulated form of cell necrosis defined by RIPK1-RIPK3-MLKL signaling. Interestingly, this finding was consistent across different particle sizes and shapes. The RIPK1-RIPK3-MLKL signaling pathway may represent a potential therapeutic target in nano- or microparticle-related diseases (crystallopathies).