Therapeutic drug monitoring of osimertinib in EGFR mutant non-small cell lung cancer by dried blood spot and plasma collection: A pilot study.

AIMS: Therapeutic drug monitoring (TDM) has led to significant improvements in individualized medical care, although its implementation in oncology has been limited to date. Tyrosine kinase inhibitors (TKIs) are a group of therapies for which TDM has been suggested. Osimertinib is one such therapy used in the treatment of epidermal growth factor receptor (EGFR) mutation-driven lung cancer. Herein, we describe a prospective pilot study involving 21 patients on osimertinib primarily as a preliminary evaluation of drug levels in a real-world setting. METHODS: Concentrations of the drug and its primary metabolites were measured with a validated liquid chromatography-mass spectrometry (LC-MS) assay across serial timepoints. As part of this study, inter-individual variability by dose and ethnicity as well as intra-individual variability across timepoints are explored. Furthermore, we attempted to validate dried blood spot (DBS)-based quantitation as an accurate alternative to plasma quantitation. RESULTS: Successful quantitation of osimertinib and primary metabolites was achieved for our subjects. Compound plasma levels were highly correlated to DBS levels. There was no significant difference in concentrations with ethnicity or dosing or intra-individual variability across timepoints. CONCLUSIONS: As such, we demonstrate that TDM for osimertinib is practical for future trials. We also validated the use of DBS as an alternative to conventional quantitation for exploration of TDM for osimertinib in larger trials and for other targeted therapies.

A Validated Assay to Quantify Osimertinib and Its Metabolites, AZ5104 and AZ7550, from Microsampled Dried Blood Spots and Plasma.

BACKGROUND: Osimertinib is an oral small-molecule tyrosine kinase receptor inhibitor used to treat non-small cell lung cancer (NSCLC) with a sensitizing epidermal growth factor receptor mutation. Patients may experience drug toxicity and require dose deescalation. The study aimed to quantitate osimertinib and its 2 active metabolites, AZ5104 and AZ7550, in microsampled dried blood spots (DBS) collected from patients with NSCLC using a hemaPEN device and compare them with plasma drug levels. METHODS: A 6-min ultrahigh-performance liquid chromatography-tandem mass spectrometry method was developed and validated using plasma and DBS. The accuracy, selectivity, matrix effect, recovery, and stability were assessed using bioanalytical validation criteria. The hematocrit effect was investigated in DBS. Drug levels were measured in 15 patients with NSCLC, and the Bland-Altman method was used to compare measurements between plasma and DBS. RESULTS: The validated assay determined accurate and precise quantities, respectively, for osimertinib in both plasma (93.2%-99.3%; 0.2%-2.3%) and DBS (96.7%-99.6%; 0.5%-10.3%) over a concentration of 1-729 ng/mL. The osimertinib metabolites, AZ5104 and AZ7550, were similarly validated in accordance with bioanalytical guidelines. For 30%-60% patient hematocrit, no hematocrit bias was observed with DBS for all analytes. The Bland-Altman method showed high concordance between plasma and DBS analyte levels. Stability experiments revealed that osimertinib and its metabolites were poorly stable in plasma at room temperature, whereas all analytes were stable in DBS for 10 days at room temperature. CONCLUSIONS: The measurement of osimertinib, AZ5104, and AZ7550 from hemaPEN microsampled DBS is a convenient and reliable approach for therapeutic drug monitoring that produces measurements consistent with plasma drug levels.

An exploratory study of a multi-species probiotic formulation and markers of health in a real-world oncological cohort in the time of covid.

INTRODUCTION: The efficacy of cancer treatments has links to the intestinal microbiome. Mucositis is a dose-limiting intestinal pro-inflammatory side effect of cancer treatments, that increases the risk of diarrhoea, mucositis, and in severe cases, febrile neutropenia. METHODS: The effect of cancer treatments on Quality of Life (QoL) was assessed using the FACT C questionnaire that included patient wellbeing and gut adverse symptoms (e.g. diarrhoea). Participants rated faecal samples via the Bristol Stool Chart. In addition, bacterial DNA was extracted from faecal samples, sequenced, and taxonomically examined. The incidence / severity of neutropenia was assessed with white blood cell and neutrophil counts. Circulating SCFAs and plasma lipopolysaccharide (LPS) endotoxin levels were recorded and correlated to intestinal mucositis. RESULTS: Improvement in bowel function, with reduction in constipation and or diarrhoea or absence of significant disturbance to bowel function was recorded in 85% of the participants. One participant developed febrile neutropenia and two developed bowel toxicity during the study, that was unrelated to the test formulation. No significant changes in microbiota alpha- and beta-diversity at the phylum and species levels respectively from baseline to end of study treatment was observed. None of the participants had raised plasma-endotoxin levels from baseline to the first and subsequent treatment cycles for their cancers. Probiotics in this cohort were deemed safe and tolerable. Significant improvement in emotional QoL scores (p = 0.015) was reported with increased number of chemotherapy cycles. In a related observational study of exceptional responders to chemotherapy, participants were found to have had a high intake of fruits, vegetables, and fibre possibly indicative of a more balanced intestinal microbiota. CONCLUSION: A multi-strain probiotic formulation was safe and tolerated in this chronically ill cohort that were undergoing oncological treatment. The probiotic formulation alleviated diarrhoea, constipation and maintained stool consistency/frequency during the multiple treatments with chemotherapy and radiotherapy. Intestinal dysbiosis that is characterised by decreased microbial diversity and increased pro-inflammatory species was not observed. Probiotic supplementation may have helped reduce dysbiosis during cancer treatments. These improvements may have been critical with the observation that emotional wellbeing was significantly improved from baseline. Hence albeit that the study had limitations, the probiotic intervention provided adjunctive treatment support to the patients. What is of scientifically plausible interest is that probiotics have a long association historically with human hosts and as such ratify their inclusion offering a significant adjunctive therapeutic potential. Future studies warrant larger sample sizes, control groups and should limit recruitment to a largely homogenous group of patients.

First-in-human study of oleclumab, a potent, selective anti-CD73 monoclonal antibody, alone or in combination with durvalumab in patients with advanced solid tumors.

BACKGROUND: CD73 upregulation in tumors leads to local immunosuppression. This phase I, first-in-human study evaluated oleclumab (MEDI9447), an anti-CD73 human IgG1λ monoclonal antibody, alone or with durvalumab in patients with advanced colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDAC), or epidermal growth factor receptor-mutant non-small-cell lung cancer (NSCLC). METHODS: Patients received oleclumab 5-40 mg/kg (dose-escalation) or 40 mg/kg (dose-expansion) intravenously every 2 weeks (Q2W), alone (escalation only) or with durvalumab 10 mg/kg intravenously Q2W. RESULTS: 192 patients were enrolled, 66 during escalation and 126 (42 CRC, 42 PDAC, 42 NSCLC) during expansion. No dose-limiting toxicities occurred during escalation. In the monotherapy and combination therapy escalation cohorts, treatment-related adverse events (TRAEs) occurred in 55 and 54%, respectively, the most common being fatigue (17 and 25%). In the CRC, PDAC, and NSCLC expansion cohorts, 60, 57, and 45% of patients had TRAEs, respectively; the most common were fatigue (15%), diarrhea (9%), and rash (7%). Free soluble CD73 and CD73 expression on peripheral T cells and tumor cells showed sustained decreases, accompanied by reduced CD73 enzymatic activity in tumor cells. Objective response rate during escalation was 0%. Response rates in the CRC, PDAC, and NSCLC expansion cohorts were 2.4% (1 complete response [CR]), 4.8% (1 CR, 1 partial response [PR]), and 9.5% (4 PRs), respectively; 6-month progression-free survival rates were 5.4, 13.2, and 16.0%. CONCLUSIONS: Oleclumab ± durvalumab had a manageable safety profile, with pharmacodynamic activity reflecting oleclumab's mechanism of action. Evidence of antitumor activity was observed in tumor types that are generally immunotherapy resistant. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov, NCT02503774; date of registration, July 17, 2015.

Metastatic primary breast neuroendocrine neoplasms: a case series.

BACKGROUND: Breast neuroendocrine neoplasms represent a rare subtype of breast cancer which have not been well studied or characterised, particularly in the metastatic setting. AIM: To present clinicopathological characteristics, treatment and outcomes of a series of patients with metastatic neuroendocrine carcinoma of the breast and review the current literature. METHODS: We performed a retrospective review to identify and describe patients with metastatic neuroendocrine carcinoma of the breast at our centre between 2011 and 2021. Medical records, pathology and imaging results were examined to evaluate the clinical and histopathological features as well as the treatment pathways and prognosis of these patients. RESULTS: We present a series of seven female patients with metastatic neuroendocrine carcinoma of the breast, as defined by the World Health Organization classification, over a period of 10 years (2011-2021) from a single centre. Median age at diagnosis was 48 years (range 39-63). Six of seven tissue samples expressed synaptophysin and chromogranin and were also oestrogen and progesterone receptor positive; median Ki-67 index was 50% (range 20-90%). All seven patients had demonstrated avidity on 18 F-FDG PET imaging, and the six who underwent 68 Ga-DOTATATE PET all had significant avidity. Treatment modalities and sequencing varied, but all patients received chemotherapy during their disease course. Six patients received three or more lines of treatment. Median overall survival was 31.8 months (range 3.7-108.6). Median progression-free survival (PFS) with first-line therapy for metastatic disease was 5.8 months (range 1.8-37.8). CONCLUSIONS: This series shows the use of multiple modalities in treating this disease, with different sequencing in different patients. Despite multiple modalities used in the first-line setting, first-line PFS remains short. Larger series and further molecular characterisation are required to aid clinicians in managing this condition and to guide optimal treatment sequencing to improve outcomes in this rare patient group.

The role of staging laparoscopy in pancreatic adenocarcinoma and its effect on patients' survival.

BACKGROUND: Prompt and accurate staging of pancreatic cancer is essential to distinguish patients to benefit from resection with curative intent and those with unresectable disease. A staging laparoscopy is used preoperatively to identify macroscopic or occult metastases not identified on imaging. This single-institution study aims to evaluate the role of staging laparoscopy in patients with pancreatic adenocarcinoma and its effect on overall survival. METHOD: Clinicopathologic data were evaluated for all patients undergoing staging laparoscopy for pancreatic adenocarcinoma from July 2014 to December 2019. The study identified 155 patients eligible for analysis. All patients were followed for at least 2 years. Clinical backgrounds, survival curves and prognostic factors were investigated. RESULTS: Resectability status among the cohort was 62 (40%) upfront resectable, 53 (34%) borderline resectable and 40 (26%) locally advanced disease. The median age was 69, with 44% male patients. Median CA19-9 value was 125 kU/L, and median CA125 value was 22 kU/L. Staging laparoscopy resulted in upstaging nine (15%) upfront resectable patients, five (9%) borderline resectable patients and ten (25%) locally advanced patients. There was positive cytology in 19 (12%), peritoneal deposits in six (4%) and peritoneal liver deposits in seven (5%) patients. Overall, the number needed to treat (NNT) to avoid an unnecessary laparotomy was eight patients. CONCLUSION: Staging laparoscopy continues to be a valuable investigation of pancreatic adenocarcinoma. In this institution, one in every eight patients undergoing a staging laparoscopy was upstaged to metastatic disease, thus avoiding an unnecessary laparotomy or a non-curative resection.

Role of zinc transporter ZIP12 in susceptibility-weighted brain magnetic resonance imaging (MRI) phenotypes and mitochondrial function.

Brain zinc dysregulation is linked to many neurological disorders. However, the mechanisms regulating brain zinc homeostasis are poorly understood. We performed secondary analyses of brain MRI GWAS and exome sequencing data from adults in the UK Biobank. Coding ZIP12 polymorphisms in zinc transporter ZIP12 (SLC39A12) were associated with altered brain susceptibility weighted MRI (swMRI). Conditional and joint association analyses revealed independent GWAS signals in linkage disequilibrium with 2 missense ZIP12 polymorphisms, rs10764176 and rs72778328, with reduced zinc transport activity. ZIP12 rare coding variants predicted to be deleterious were associated with similar impacts on brain swMRI. In Neuro-2a cells, ZIP12 deficiency by short hairpin RNA (shRNA) depletion or CRISPR/Cas9 genome editing resulted in impaired mitochondrial function, increased superoxide presence, and detectable protein carbonylation. Inhibition of Complexes I and IV of the electron transport chain reduced neurite outgrowth in ZIP12 deficient cells. Transcriptional coactivator PGC-1α, mitochondrial superoxide dismutase (SOD2), and chemical antioxidants α-tocopherol, MitoTEMPO, and MitoQ restored neurite extension impaired by ZIP12 deficiency. Mutant forms of α-synuclein and tau linked to familial Parkinson's disease and frontotemporal dementia, respectively, reduced neurite outgrowth in cells deficient in ZIP12. Zinc and ZIP12 may confer resilience against neurological diseases or premature aging of the brain.

Emerging biological therapies for the treatment of malignant pleural mesothelioma.

Introduction: Malignant pleural mesothelioma (MPM) has limited treatment options with minimal new therapy approvals for unresectable disease in the past 15 years. However, considerable work has occurred to develop immunotherapies and biomarker driven therapy to improve patient outcomes over this period.Areas covered: This review examines current standard of care systemic therapy in the first- and second line setting. The last 12 months has seen 2 significant trials (Checkmate 743 and CONFIRM) which provide evidence supporting the role of immunotherapy in the management of MPM. Further trials are underway to assess the role of combination chemoimmunotherapy and personalized therapy. Additionally, a large number of clinical trials are ongoing to assess the efficacy of oncoviral, dendritic cell, anti-mesothelin and chimeric antigen receptor T cell therapy in the treatment of MPM.Expert opinion: Recent Phase III trial results have established a role for immunotherapy in the management of MPM. The optimal sequencing and combination of chemotherapy and immunotherapy remains to be determined. Novel therapies for MPM are promising however efficacy remains to be determined and issues remain regarding access to and delivery of these therapies.

Treatment with a CD40 Antagonist Antibody Reverses Severe Proteinuria and Loss of Saliva Production and Restores Glomerular Morphology in Murine Systemic Lupus Erythematosus.

CD40 is a costimulatory receptor on APCs that is critical for the induction and maintenance of humoral and cell-mediated immunity. Accordingly, CD40 and its ligand, CD40L, have long been considered targets for the treatment of autoimmune diseases. We developed a rat/mouse chimeric anti-mouse CD40 antagonist mAb, 201A3, and evaluated its ability to alleviate murine lupus. Treatment of NZB/W-F1 mice with 201A3 after the onset of severe proteinuria rapidly reversed established severe proteinuria and nephritis and largely restored normal glomerular and tubular morphology. This coincided with a normalization of the expression of genes associated with proteinuria and injury by kidney parenchymal cells. Anti-CD40 treatment also prevented and reversed loss of saliva production and sialadenitis. These effects on kidney and salivary gland function were confirmed using mice of a second strain, MRL/Mp-lpr/lpr, and extended to alleviating joint inflammation. Immunologically, anti-CD40 treatment disrupted multiple processes that contribute to the pathogenesis of systemic lupus erythematosus (SLE), including autoreactive B cell activation, T effector cell function in target tissues, and type I IFN production. This ability to disrupt disease-critical immunological mechanisms, to reverse glomerular and tubular injury at the cellular and gene expression levels, and to confer exceptional therapeutic efficacy suggests that CD40 is a central disease pathway in murine SLE. Thus, a CD40 antagonist Ab could be an effective therapeutic in the treatment of SLE.

Australian recommendations for the management of hepatocellular carcinoma: a consensus statement.

INTRODUCTION: Hepatocellular carcinoma (HCC) is a leading cause of cancer deaths both globally and in Australia. Surveillance for HCC in at-risk populations allows diagnosis at an early stage, when potentially curable. However, most Australians diagnosed with HCC die of the cancer or of liver disease. In the changing landscape of HCC management, unique challenges may lead to clinical practice variation. As a result, there is a need to identify best practice management of HCC in an Australian context. This consensus statement has been developed for health professionals involved in the care of adult patients with HCC in Australia. It is applicable to specialists, general medical practitioners, nurses, health coordinators and hospital administrators. METHODS AND RECOMMENDATIONS: This statement has been developed by specialists in hepatology, radiology, surgery, oncology, palliative care, and primary care, including medical practitioners and nurses. The statement addresses four main areas relevant to HCC management: epidemiology and incidence, diagnosis, treatment, and patient management. A modified Delphi process was used to reach consensus on 31 recommendations. Principal recommendations include the adoption of surveillance strategies, use of multidisciplinary meetings, diagnosis, treatment options and patient management. CHANGES IN MANAGEMENT AS A RESULT OF THIS STATEMENT: This consensus statement will simplify HCC patient management and reduce clinical variation. Ultimately, this should result in better outcomes for patients with HCC.

Characterization hiPSC-derived neural progenitor cells and neurons to investigate the role of NOS1AP isoforms in human neuron dendritogenesis.

Abnormal dendritic arbor development has been implicated in a number of neurodevelopmental disorders, such as autism and Rett syndrome, and the neuropsychiatric disorder schizophrenia. Postmortem brain samples from subjects with schizophrenia show elevated levels of NOS1AP in the dorsolateral prefrontal cortex, a region of the brain associated with cognitive function. We previously reported that the long isoform of NOS1AP (NOS1AP-L), but not the short isoform (NOS1AP-S), negatively regulates dendrite branching in rat hippocampal neurons. To investigate the role that NOS1AP isoforms play in human dendritic arbor development, we adapted methods to generate human neural progenitor cells and neurons using induced pluripotent stem cell (iPSC) technology. We found that increased protein levels of either NOS1AP-L or NOS1AP-S decrease dendrite branching in human neurons at the developmental time point when primary and secondary branching actively occurs. Next, we tested whether pharmacological agents can decrease the expression of NOS1AP isoforms. Treatment of human iPSC-derived neurons with d-serine, but not clozapine, haloperidol, fluphenazine, or GLYX-13, results in a reduction in endogenous NOS1AP-L, but not NOS1AP-S, protein expression; however, d-serine treatment does not reverse decreases in dendrite number mediated by overexpression of NOS1AP isoforms. In summary, we demonstrate how an in vitro model of human neuronal development can help in understanding the etiology of schizophrenia and can also be used as a platform to screen drugs for patients.

Lumbosacral intervertebral disk extrusions in 13 dogs.

OBJECTIVE: To describe the clinical presentation, magnetic resonance imaging (MRI) findings, and outcome of dogs treated surgically for lumbosacral intervertebral disk extrusion (IVDE). STUDY DESIGN: Retrospective study. ANIMALS: Thirteen dogs. METHODS: Records and MRI studies of dogs with intraoperatively confirmed lumbosacral IVDE were reviewed. MRI features of thoracolumbar IVDE were applied to all cases. Postoperative outcome was subjectively assessed as excellent, good, or poor. RESULTS: All dogs had an acute or subacute onset of lumbosacral pain and nerve root signature. Seven dogs had neurological deficits. MRI revealed lateralized herniated disk material and partial to complete disk degeneration in all cases; the extradural material extended cranial and/or caudally from the disk space in 10 cases. All dogs underwent L7-S1 dorsal laminectomy and removal of extruded disk material. In six dogs, surgery was complicated by inflammatory changes, including one case of epidural steatitis. On reexamination 4-6 weeks postsurgery, outcome was judged as excellent in 11 dogs and poor in the remaining 2 due to contralateral nerve root signature in one case and nonambulatory paraparesis and urinary incontinence in the case with steatitis. CONCLUSION: Lumbosacral IVDE in dogs was characterized by acute/subacute onset of lumbosacral pain and nerve root signature and lateralized and often dispersed extradural material over a degenerated L7-S1 intervertebral disk on MRI. Early decompressive dorsal laminectomy generally resulted in excellent clinical outcome. CLINICAL SIGNIFICANCE: Observation of these clinical and imaging features in dogs should prompt clinical suspicion of lumbosacral IVDE.

ALK-Rearranged Non-Small Cell Lung Cancer in 2020: Real-World Triumphs in an Era of Multigeneration ALK-Inhibitor Sequencing Informed by Drug Resistance Profiling.

Since its discovery in 2007, we have seen the lives of patients diagnosed with advanced anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancers (NSCLC) transform with the advent of molecular therapies with first-, second-, and third-generation ALK inhibitors now available in the clinic. Despite great gains in patient survival now measured in years and preserved quality of life with targeted therapies, drug resistance is unfortunately inevitably encountered in this rare and unique molecular subset of lung cancer, and patients will eventually succumb to the disease. As these patients are often young, fit, and never smokers, the clinical and scientific communities have aligned to expedite drug development and access. Drug resistance profiling and further strategies are being explored through clinical trials, including the evaluation of specific drug sequencing and combinations to overcome such resistance and promote patient longevity. The cases of this report focus on precision medicine and aim to portray the pertinent aspects to consider when treating ALK-rearranged NSCLC in 2020, an ever-shifting space. By way of case examples, this report offers valuable information to the treating clinician, including the evolution of systemic treatments and the management of oligo-progression and multisite drug resistance. With the maturation of real-world data, we are fortunate to be experiencing quality and length of life for patients with this disease surpassing prior expectations in advanced lung cancer. KEY POINTS: This report focuses on the importance of genetic analysis of serial biopsies to capture the dynamic therapeutic vulnerabilities of a patient's tumor, providing a perspective on the complexity of ALK tyrosine kinase inhibitor (ALKi) treatment sequencing. These case examples contribute to the literature on ALK-rearranged and oncogene addicted non-small cell lung cancer (NSCLC), providing a framework for care in the clinic. In oligo-progressive disease, local ablative therapy and continuation of ALKi postprogression should be considered with potential for sustained disease control. ALK G1202R kinase domain mutations (KDM), highly prevalent at resistance to second-generation ALKi resistances, may emerge in non-EML4-ALK variant 3 cases and is sensitive to third-generation lorlatinib. When in compound with one or more ALK KDMs, resistance to lorlatinib is expected. In the case of rampantly progressive disease, rebiopsy and redefining biology in a timely manner may be informative.

Contrast coding in the electrosensory system: parallels with visual computation.

To identify and interact with moving objects, including other members of the same species, an animal's nervous system must correctly interpret patterns of contrast in the physical signals (such as light or sound) that it receives from the environment. In weakly electric fish, the motion of objects in the environment and social interactions with other fish create complex patterns of contrast in the electric fields that they produce and detect. These contrast patterns can extend widely over space and time and represent a multitude of relevant features, as is also true for other sensory systems. Mounting evidence suggests that the computational principles underlying contrast coding in electrosensory neural networks are conserved elements of spatiotemporal processing that show strong parallels with the vertebrate visual system.

Astaxanthin-Shifted Gut Microbiota Is Associated with Inflammation and Metabolic Homeostasis in Mice.

BACKGROUND: Astaxanthin is a red lipophilic carotenoid that is often undetectable in human plasma due to the limited supply in typical Western diets. Despite its presence at lower than detectable concentrations, previous clinical feeding studies have reported that astaxanthin exhibits potent antioxidant properties. OBJECTIVE: We examined astaxanthin accumulation and its effects on gut microbiota, inflammation, and whole-body metabolic homeostasis in wild-type C57BL/6 J (WT) and ß-carotene oxygenase 2 (BCO2) knockout (KO) mice. METHODS: Six-wk-old male and female BCO2 KO and WT mice were provided with either nonpurified AIN93M (e.g., control diet) or the control diet supplemented with 0.04% astaxanthin (wt/wt) ad libitum for 8 wk. Whole-body energy expenditure was measured by indirect calorimetry. Feces were collected from individual mice for short-chain fatty acid assessment. Hepatic astaxanthin concentrations and liver metabolic markers, cecal gut microbiota profiling, inflammation markers in colonic lamina propria, and plasma samples were assessed. Data were analyzed by 3-way ANOVA followed by Tukey's post hoc analysis. RESULTS: BCO2 KO but not WT mice fed astaxanthin had ∼10-fold more of this compound in liver than controls (P < 0.05). In terms of the microbiota composition, deletion of BCO2 was associated with a significantly increased abundance of Mucispirillum schaedleri in mice regardless of gender. In addition to more liver astaxanthin in male KO compared with WT mice fed astaxanthin, the abundance of gut Akkermansia muciniphila was 385% greater, plasma glucagon-like peptide 1 was 27% greater, plasma glucagon and IL-1ß were 53% and 30% lower, respectively, and colon NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome activation was 23% lower (all P < 0.05) in male KO mice than the WT mice. CONCLUSIONS: Astaxanthin affects the gut microbiota composition in both genders, but the association with reductions in local and systemic inflammation, oxidative stress, and improvement of metabolic homeostasis only occurs in male mice.

High Metabolic Tumour Volume on 18-Fluorodeoxyglucose Positron Emission Tomography Predicts Poor Survival from Neuroendocrine Neoplasms.

INTRODUCTION: 18-Fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) avidity in neuroendocrine neoplasms (NENs) has been associated with higher-grade disease. 18F-FDG avidity and high SUVmax have been demonstrated to predict poor outcome. Quantitative metrics of 18F-FDG PET, specifically metabolic tumour volume (MTV) and total lesion glycolysis (TLG), have been shown to be prognostic factors in other malignancies, but these have not been investigated to date in NENs. METHODS: Patients with NEN undergoing 18F-FDG at Royal North Shore Hospital from 2012 to 2018 were included. Images were analysed with automated segmentation (SUV cut-off of 4) followed by contour verification by a nuclear medicine physician and manual segmentation where required. Variables collected included patient age, histological grade, MTV, TLG, and SUVmax/SUVmean. The primary outcome was overall survival (OS), and the secondary outcome was progression-free survival (PFS). Univariate (UV) and multivariate (MV) analyses were performed for OS and PFS for MTV and TLG separately. For UV analysis, the median MTV and TLG were used to dichotomise the cohort. MTV/TLG for NENs of different histological grade were compared using ANOVA. RESULTS: One hundred and ninety patients were included (median age 63.5, 49% female). Primary site: 42% small bowel, 32% pancreas, 15% other gastrointestinal, 6% lung, 6% other. Grade for gastroenteropancreatic NENs and bronchial NEN: G1/typical carcinoid 37%, G2/atypical carcinoid 40%, G3/large-cell/small-cell neuroendocrine carcinoma 16%, unknown 8%. Median MTV was 4.83 mL (range 0-3,161 mL) and median TLG was 29.22. Patients with high MTV had worse median OS compared to those with low MTV (29.7 months vs. not reached, HR 4.1, 95% CI 2.25-7.49, p < 0.00001). Considered as a continuous variable, MTV predicted for poorer OS on UV (p < 0.00001) and MV (p = 0.003) analyses. Whilst histological grade was significant on both UV and MV, SUVmax was significant on UV (p < 0.00001) but not MV (p = 0.76). Tumours of higher grade had higher MTV (mean MTV - G1: 39.6 mL, G2: 107 mL, G3: 337 mL; p = 0.0001 by ANOVA). CONCLUSIONS: Quantitative analysis of 18F-FDG PET in NEN is feasible. High MTV/TLG are predictors of poor prognosis in NEN. Further analyses are underway to investigate a larger cohort of NEN patients.

The impact of neutrophil-lymphocyte ratio on risk reclassification of patients with advanced renal cell cancer to guide risk-directed therapy.

Background: An elevated neutrophil-lymphocyte ratio (NLR) is associated with poor prognosis in advanced renal cell carcinoma (RCC). We examined whether the addition of NLR improves the risk reclassification of advanced RCC using current prognostic tools from the Memorial Sloan Kettering Cancer Center (MSKCC) and International Metastatic Renal Cell Carcinoma Database Consortium (IMDC).Methods: Using randomised data from the COMPARZ trial of first-line pazopanib vs. sunitinib in advanced RCC, we constructed multivariable models containing MSKCC and IMDC predictor variables with and without NLR. We evaluated model discrimination using the concordance index (C-index). We computed net reclassification improvement to quantify patient reclassification into low/intermediate/poor risk groups with the addition of NLR.Results: Of 1102 patients, NLR ≥ 5 (16%) was associated with shorter survival adjusting for MSKCC variables (adjusted HR 1.89, p < .001). Adding NLR to MSKCC variables increased the C-index by 0.01. Among patients who died before 24 months (N = 415), adding NLR reclassified 8% and 2% to a higher and lower risk category, respectively. Among those alive at 24 months (N = 636), adding NLR reclassified 4% and 1% to a higher and lower risk category, respectively. This finding translates to a net benefit of eight additional patients who die within 24 months correctly identified as poor risk per 1000 patients tested. We obtained similar results when evaluating NLR with IMDC variables.Conclusions: NLR does not substantially improve risk reclassification over pre-existing prognostic tools. MSKCC and IMDC classifications remain the standard for guiding risk-directed therapy and trial stratification of patients with advanced RCC.

Distinct TP53 Mutation Types Exhibit Increased Sensitivity to Ferroptosis Independently of Changes in Iron Regulatory Protein Activity.

The tumor suppressor gene TP53 is the most commonly mutated gene in human cancer. In addition to loss of tumor suppressor functions, mutations in TP53 promote cancer progression by altering cellular iron acquisition and metabolism. A newly identified role for TP53 in the coordination of iron homeostasis and cancer cell survival lies in the ability for TP53 to protect against ferroptosis, a form of iron-mediated cell death. The purpose of this study was to determine the extent to which TP53 mutation status affects the cellular response to ferroptosis induction. Using H1299 cells, which are null for TP53, we generated cell lines expressing either a tetracycline inducible wild-type (WT) TP53 gene, or a representative mutated TP53 gene from six exemplary "hotspot" mutations in the DNA binding domain (R273H, R248Q, R282W, R175H, G245S, and R249S). TP53 mutants (R273H, R248Q, R175H, G245S, and R249S) exhibited increased sensitivity ferroptosis compared to cells expressing WT TP53. As iron-mediated lipid peroxidation is critical for ferroptosis induction, we hypothesized that iron acquisition pathways would be upregulated in mutant TP53-expressing cells. However, only cells expressing the R248Q, R175H, and G245S TP53 mutation types exhibited statistically significant increases in spontaneous iron regulatory protein (IRP) RNA binding activity following ferroptosis activation. Moreover, changes in the expression of downstream IRP targets were inconsistent with the observed differences in sensitivity to ferroptosis. These findings reveal that canonical iron regulatory pathways are bypassed during ferroptotic cell death. These results also indicate that induction of ferroptosis may be an effective therapeutic approach for tumor cells expressing distinct TP53 mutation types.

Long-term outcomes after pantarsal arthrodesis with medial plate fixation without external coaptation in 30 dogs.

OBJECTIVE: To report long-term outcomes of dogs treated with pantarsal arthrodesis (PTA) with medial plate fixation without external coaptation. STUDY DESIGN: Retrospective case series. ANIMALS: Client-owned dogs (n = 30). METHODS: Medical records of dogs that had undergone a PTA with a medially applied plate without adjunctive rigid external coaptation were reviewed. Data collected included signalment, complications, and assessment of function at last physical examination. Follow-up information was obtained by phone conversations with owners. Complications were classified as minor, major II, major I, and catastrophic. RESULTS: Thirty-six PTA were performed in 30 dogs. Recorded complications included eight (22.2%) minor complications, 11 (30.6%) major II complications and 11 (30.6%) major I complications. One (2.8%) dog required amputation because of catastrophic complication. Owners provided follow-up for 26 dogs at a median duration of 1215 days (range, 325-3495) after surgery. The outcome was reported as full function in 12 dogs and acceptable function in 14 dogs, with no owners reporting unacceptable function. The owner of the dog in which amputation was required was not contacted. Incorrect contact details prevented owner follow-up in the other three dogs, but all had acceptable function at last veterinary follow up. CONCLUSION: Dogs treated with PTA by medially applied plate had a high incidence of complications requiring surgical or medical management, although full or acceptable function was achieved in 29 of 30 dogs. CLINICAL SIGNIFICANCE: Pantarsal arthrodesis offers a predictably good medium to long-term outcome in spite of a high risk of complications.

The vermiform appendix: an immunological organ sustaining a microbiome inoculum.

The hominoid vermiform appendix has been characterized as a diverticulum of the caecum and describes an entity at the juxtaposition of the colon in the confluence of tanias. The independent development of the lymphoid follicle centres of the appendix is progressed at birth in the presence of the intestinal commensal microbiome, an obligatory prompt for the diversification of intestinal and extra-intestinal mucosal immunological tissue. In the vermiform appendix, this activity is centred on further developing the inventory of primary antibodies and the maturation of T- and B-lymphocyte cells in the follicles within the lymphoid tissue. Furthermore, the columnar epithelia, enterocytes and goblet cells comprise the complement of cells that occupy the lamina propria and muscularis mucosae of the vermiform appendix's mucosa, while macrophages and an abundance of immunoglobulin A and immunoglobulin G generating plasma cells seed the lamina propria Intraepithelial immune cells consisting predominantly of specific CD8+ T regulatory lymphocytes occupy sites in the appendix analogous to those present in the intestinal epithelia of the caecal colon. The complement of bacterial genera concealed in the vermiform appendix is posited extant as a biofilm inoculum of the intestinal commensal microbiome. This facilitates re-inoculation of the proximal colon and to a lesser degree the terminal ilium post an intestinal perturbation such as occurs with daily lifestyle stressors, dietary choices and the short-term administration of antibiotics rather than an infectious fulminant colitis. A plausible appreciation results of the importance of multiple immunological aspects of a healthy vermiform appendix and the provision of a commensal biofilm to the gut that repairs a dysbiotic microbiome contributing to balancing intestinal pro- and anti-inflammatory activity for maintaining homeostasis in the gut. Since the composition of the gut microbiome can vary over the short-term and long-term, it is plausible that the appendix inoculum may be instrumental in maintaining the intestinal microbiome.