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 Proteomic View of Cellular and Molecular Effects of Cannabis

Cannabis (Cannabis sativa), popularly known as marijuana, is the most commonly used psychoactive substance and is considered illicit in most countries worldwide. However, a growing body of research has provided evidence of the therapeutic properties of chemical components of cannabis known as cannabinoids against several diseases including Alzheimer's disease (AD), multiple sclerosis (MS), Parkinson's disease, schizophrenia and glaucoma; these have prompted changes in medicinal cannabis legislation. The relaxation of legal restrictions and increased socio-cultural acceptance has led to its increase in both medicinal and recreational usage. Several biochemically active components of cannabis have a range of effects on the biological system. There is an urgent need for more research to better understand the molecular and biochemical effects of cannabis at a cellular level, to understand fully its implications as a pharmaceutical drug. Proteomics technology is an efficient tool to rigorously elucidate the mechanistic effects of cannabis on the human body in a cell and tissue-specific manner, drawing conclusions associated with its toxicity as well as therapeutic benefits, safety and efficacy profiles. This review provides a comprehensive overview of both in vitro and in vivo proteomic studies involving the cellular and molecular effects of cannabis and cannabis-derived compounds.

Presymptomatic Dutch-Type Hereditary Cerebral Amyloid Angiopathy-Related Blood Metabolite Alterations

BACKGROUND

Cerebral amyloid angiopathy (CAA) is one of the major causes of intracerebral hemorrhage and vascular dementia in older adults. Early diagnosis will provide clinicians with an opportunity to intervene early with suitable strategies, highlighting the importance of pre-symptomatic CAA biomarkers.

OBJECTIVE

Investigation of pre-symptomatic CAA related blood metabolite alterations in Dutch-type hereditary CAA mutation carriers (D-CAA MCs).

METHODS

Plasma metabolites were measured using mass-spectrometry (AbsoluteIDQ® p400 HR kit) and were compared between pre-symptomatic D-CAA MCs (n = 9) and non-carriers (D-CAA NCs, n = 8) from the same pedigree. Metabolites that survived correction for multiple comparisons were further compared between D-CAA MCs and additional control groups (cognitively unimpaired adults).

RESULTS

275 metabolites were measured in the plasma, 22 of which were observed to be significantly lower in theD-CAAMCs compared to D-CAA NCs, following adjustment for potential confounding factors age, sex, and APOE ε4 (p < 00.05). After adjusting for multiple comparisons, only spermidine remained significantly lower in theD-CAAMCscompared to theD-CAA NCs (p  < 0.00018). Plasma spermidine was also significantly lower in D-CAA MCs compared to the cognitively unimpaired young adult and older adult groups (p < 0.01). Spermidinewas also observed to correlate with CSF Aβ40 (rs = 0.621, p = 0.024), CSF Aβ42 (rs = 0.714, p = 0.006), and brain Aβ load (rs = -0.527, p = 0.030).

CONCLUSION

The current study provides pilot data on D-CAA linked metabolite signals, that also associated with Aβ neuropathology and are involved in several biological pathways that have previously been linked to neurodegeneration and dementia.

Overlapping roles for PLK1 and Aurora A during meiotic centrosome biogenesis in mouse spermatocytes

The establishment of bipolar spindles during meiotic divisions ensures faithful chromosome segregation to prevent gamete aneuploidy. We analyzed centriole duplication, as well as centrosome maturation and separation during meiosis I and II using mouse spermatocytes. The first round of centriole duplication occurs during early prophase I, and then, centrosomes mature and begin to separate by the end of prophase I to prime formation of bipolar metaphase I spindles. The second round of centriole duplication occurs at late anaphase I, and subsequently, centrosome separation coordinates bipolar segregation of sister chromatids during meiosis II. Using a germ cell-specific conditional knockout strategy, we show that Polo-like kinase 1 and Aurora A kinase are required for centrosome maturation and separation prior to metaphase I, leading to the formation of bipolar metaphase I spindles. Furthermore, we show that PLK1 is required to block the second round of centriole duplication and maturation until anaphase I. Our findings emphasize the importance of maintaining strict spatiotemporal control of cell cycle kinases during meiosis to ensure proficient centrosome biogenesis and, thus, accurate chromosome segregation during spermatogenesis.

Reproducibly sampling SARS-CoV-2 genomes across time, geography, and viral diversity

The COVID-19 pandemic has led to a rapid accumulation of SARS-CoV-2 genomes, enabling genomic epidemiology on local and global scales. Collections of genomes from resources such as GISAID must be subsampled to enable computationally feasible phylogenetic and other analyses. We present genome-sampler, a software package that supports sampling collections of viral genomes across multiple axes including time of genome isolation, location of genome isolation, and viral diversity. The software is modular in design so that these or future sampling approaches can be applied independently and combined (or replaced with a random sampling approach) to facilitate custom workflows and benchmarking. genome-sampler is written as a QIIME 2 plugin, ensuring that its application is fully reproducible through QIIME 2's unique retrospective data provenance tracking system. genome-sampler can be installed in a conda environment on macOS or Linux systems. A complete default pipeline is available through a Snakemake workflow, so subsampling can be achieved using a single command. genome-sampler is open source, free for all to use, and available at https://caporasolab.us/genome-sampler. We hope that this will facilitate SARS-CoV-2 research and support evaluation of viral genome sampling approaches for genomic epidemiology.

Reproducibly sampling SARS-CoV-2 genomes across time, geography, and viral diversity

The COVID-19 pandemic has led to a rapid accumulation of SARS-CoV-2 genomes, enabling genomic epidemiology on local and global scales. Collections of genomes from resources such as GISAID must be subsampled to enable computationally feasible phylogenetic and other analyses. We present genome-sampler, a software package that supports sampling collections of viral genomes across multiple axes including time of genome isolation, location of genome isolation, and viral diversity. The software is modular in design so that these or future sampling approaches can be applied independently and combined (or replaced with a random sampling approach) to facilitate custom workflows and benchmarking. genome-sampler is written as a QIIME 2 plugin, ensuring that its application is fully reproducible through QIIME 2’s unique retrospective data provenance tracking system. genome-sampler can be installed in a conda environment on macOS or Linux systems. A complete default pipeline is available through a Snakemake workflow, so subsampling can be achieved using a single command. genome-sampler is open source, free for all to use, and available at https://caporasolab.us/genome-sampler. We hope that this will facilitate SARS-CoV-2 research and support evaluation of viral genome sampling approaches for genomic epidemiology.

An external quality assurance trial to assess mass spectrometry protein testing facilities for identifying multiple human peptides

The application of proteomic liquid chromatography mass spectrometry (LC-MS) for identifying proteins and peptides associated with human disease is rapidly growing in clinical diagnostics. However, the ability to accurately and consistently detect disease-associated peptides remains clinically uncertain. Variability in diagnostic testing occurs in part due to the absence of appropriate reference testing materials and standardised clinical guidelines for proteomic testing. In addition, multiple proteomic testing pipelines have not been fully assessed through external quality assurance (EQA). This trial was therefore devised to evaluate the performance of a small number of mass spectrometry (MS) testing facilities to (i) evaluate the EQA material for potential usage in a proteomic quality assurance program, and to (ii) identify key problem areas associated with human peptide testing. Five laboratories were sent six peptide reference testing samples formulated to contain a total of 35 peptides in differing ratios of light (natural) to heavy (labelled) peptides. Proficiency assessment of laboratory data used a modified approach to similarity and dissimilarity testing that was based on Bray-Curtis and Sorensen indices. Proficiency EQA concordant consensus values could not be derived from the assessed data since none of the laboratories correctly identified all reference testing peptides in all samples. However, the produced data may be reflective of specific inter-laboratory differences for detecting multiple peptides since no two testing pipelines used were the same for any laboratory. In addition, laboratory feedback indicated that peptide filtering of the reference material was a common key problem area prior to analysis. These data highlight the importance of an EQA programme for identifying underlying testing issues so that improvements can be made and confidence for clinical diagnostic analysis can be attained.

Recovery of Kidney Dysfunction After Transcatheter Aortic Valve Implantation (from the Northern New England Cardiovascular Disease Study Group)

Acute Kidney Recovery (AKR) is a potential benefit of transcatheter aortic valve implantation (TAVI). We determined the incidence and predictors of AKR in a multicenter prospective registry of TAVI. After excluding patients on dialysis or who died within 48 hours postprocedure, we reviewed 1,502 consecutive patients underwent TAVI in Northern New England from 2012 to 2017. Patients were categorized into 3 groups based on the change in postprocedure estimated glomerular filtration rate (eGFR): Acute Kidney Injury (AKI, decrease in eGFR >25%), AKR (increase in eGFR >25%) or no change in kidney function on discharge creatinine following TAVI. We then focused in patients with baseline chronic kidney disease (CKD defined as eGFR ≤60 ml/min; n = 755) and developed multivariate predictor models to determine the clinical and procedural variables associated with AKR. For the TAVI cohort (n = 1,502), the overall incidence of AKR was 17.8%. AKR was threefold higher in patients with eGFR ≤60 ml/min as compared to those with eGFR >60 ml/min (26.6% vs 8.9%, p < 0.001). In the CKD population, hospital complications were similar among patients with no change in renal function and AKR; patients with AKI had a higher rate of hospital mortality, pacemaker implantation, length of hospitalization, and transfusions. Using multivariable logistic regression, moderate to severe lung disease, eGFR < 50 ml/min and previous aortic valve surgery were found to be independent predictors of AKR. Patients with diabetes mellitus, baseline anemia, and Society of thoracic surgeons score >6.1 were less likely to develop AKR. In conclusion, AKR occurred in 1 of 4 of all TAVI patients with baseline CKD and was a more frequent phenomena than AKI. Patients with decreased lung function, previous aortic valve surgery and worse baseline renal function were more likely to demonstrate AKR, whereas patients with diabetes mellitus, baseline anemia, and higher Society of thoracic risk scores were less likely to see improvements in renal function after TAVI.

A Low Impact Approach to Infected Pancreatic Necrosis: Review of a Case Series

BACKGROUND

Infected pancreatic necrosis develops in approximately one third of patients with necrotizing pancreatitis and can lead to significant morbidity and mortality rates. Historically, open necrosectomy has been the mainstay of management for these patients but is in itself a morbid procedure. In recent times, minimally invasive techniques have evolved to allow a less invasive approach to these patients. Percutaneous catheter drainage of infected pancreatic necrosis is a technique that has been demonstrated to be potentially useful in the treatment of this group of patients.

PATIENTS AND METHODS

The aim of this study was to review outcomes and define the technique of percutaneous catheter drainage in patients with infected pancreatic necrosis. All patients with infected pancreatic necrosis were exclusively treated with percutaneous drainage over the study period. Acute Physiology and Chronic Health Evaluation (APACHE) II score, number and size of drains, drainage technique and drain management, hospital and intensive care unit (ICU) stay, nutritional requirements, and morbidity and mortality data were evaluated for the patient group. Computed tomography (CT) scans were used to assess the progression of the disease process and the effectiveness of the treatment.

RESULTS

There were nine patients with infected pancreatic necrosis in this case series between 2007 and 2012, all of whom were treated with percutaneous catheter drainage alone. The median APACHE II score in the patient group was 11, with a median stay in the ICU of 3 d and median hospital stay of 41 d. On average, nine CT scans were performed per patient during the hospital admission. A median of three drains were inserted per patient, and in the course of the study, it was evident that the larger drain size was the most effective. In eight of the nine patients in the group, complications developed that were both directly and indirectly related to the pancreatitis, but were effectively managed. There were no deaths.

CONCLUSION

Percutaneous catheter drainage as a stand-alone intervention is an alternative strategy for infected pancreatic necrosis and can be used with acceptable morbidity and mortality rates in this challenging group of patients.

Abstract WMP120: Radiosurgery Induces Novel Protein Changes on the Endothelium of Arteriovenous Malformations: Potential for Therapeutic Targets

Introduction: Brain arteriovenous malformations (AVMs) are a significant cause of hemorrhagic stroke. Almost one third are untreatable using current methods. We aim to use stereotactic radiosurgery as a priming tool to elicit novel protein expression on irradiated AVM vessels and targeting with thrombotic antibody-conjugates to induce rapid thrombosis and vessel closure.

Hypothesis: Radiosurgery induces novel protein changes on the AVM endothelium that are potential therapeutic targets.

Methods: A model arteriovenous fistula (AVF) formed in rats was irradiated by GammaKnife (20Gy) or sham-irradiated. After 24h, animals were perfused with EZ-link Sulfo-NHS-LC Biotin to label surface-accessible proteins. Biotinylated AVFs were dissected, pooled (n=4/group) and protein extracted. Biotin-labelled proteins were enriched on streptavidin-agarose beads before LC-MS/MS using SWATH acquisition label-free mass spectrometry.

Results: At 24h post-irradiation, 280 surface-associated proteins were identified in sham and irradiated extracts. Of these, 56 were up-regulated in irradiated AVMs (greater than 1.5-fold change vs sham). Radiation increased fibrinogen α/β (1.5-fold), platelet factor 4 (16-fold) and plasminogen (2-fold), suggesting enhanced adhesion of blood-borne molecules to the vessel wall. Twenty-eight mitochondrial proteins increased, including manganese superoxide dismutase (2-fold), which may reflect radiation-induced changes in subcellular localization or cell lysis causing intracellular molecule release and entrapment. Troponin I (cardiac) and tropomyosin 1α, actin-associated proteins externalized under stress, increased 14- and 4-fold. Secreted and membrane proteins were also identified (e.g. clusterin, 1.5-fold; CD93, 5-fold; Ras-related Rab18, 1.8-fold).

Conclusions: Using in vivo biotin labelling, we have identified a series of novel surface-accessible proteins induced by radiosurgery that are potential therapeutic targets. Externalization of intracellular proteins may provide unique radiation-stimulated candidates for vascular targeting in AVMs.

Toll-like receptor 4 (Tlr4) knockout rats produced by transcriptional activator-like effector nuclease (TALEN)-mediated gene inactivation

Genetically engineered mice are a valuable resource for studies of the behavioral effects of ethanol. However, for some behavioral tests of ethanol action, the rat is a superior model organism. Production of genetically engineered rats has been severely hampered due to technical limitations. Here we utilized a promising new technique for efficient site-specific gene modification to create a novel gene knockout rat line. This approach is based on transcriptional activator-like effector nucleases (TALENs). TALENs function in pairs and bind DNA in a sequence-specific manner. Upon binding to the target sequence, a functional nuclease is reconstituted that creates double-stranded breaks in the DNA that are efficiently repaired by non-homologous end joining. This error-prone process often results in deletions of varying lengths at the targeted locus. The toll-like receptor 4 (Tlr4) gene was selected for TALEN-mediated gene inactivation. Tlr4 has been implicated in ethanol-induced neuroinflammation and neurodegeneration, as well as multiple ethanol-induced behavioral effects. To generate Tlr4 knockout rats, a pair of TALEN constructs was created that specifically target Exon 1 immediately downstream of the start of translation. TALEN mRNAs were microinjected into the cytoplasm of one-cell Wistar rat embryos. Of 13 live-born pups that resulted, one harbored a mutation in Exon 1 of Tlr4. The mutated allele consisted of a 13 base-pair deletion that was predicted to create a frameshift mutation after amino acid 25. This founder rat successfully transmitted the mutation to F1 offspring. Heterozygous F1 offspring were interbred to produce homozygous F2 animals. Homozygous mutants expressed the 13-bp deletion in Tlr4 mRNA. In contrast to control rats that produced a robust increase in plasma tumor necrosis factor alpha in response to a lipopolysaccharide challenge, homozygous rats had a markedly attenuated response. Thus, the mutant Tlr4 allele generated by TALEN-mediated gene inactivation represents a null allele. This knockout rat line will be valuable for studies of ethanol action as well as more general inflammatory conditions including septic shock. In conclusion, TALEN-mediated gene targeting in rat zygotes represents an inexpensive, efficient, and rapid method for creating genetically engineered rats.

Patterns of scald injuries in children--has anything changed?

The objective was to study presentation patterns of scald injuries in children and suggest potential countermeasures to reduce these injuries. We retrospectively studied scald injuries in children attending an urban paediatric emergency department between January 1st and December 31st 2008. Data was extracted from our emergency department database using search terms 'burn', 'scald', 'other burn'. Scalds were analysed for; age at presentation, sex, time of presentation, causal agent, scald outcome and treatment required. Burns accounted for 280 (0.66%) of total attendees, 161 (57%) were scalds. 127 (79%) were under 5 years old (mean age 42 months). 104 (65%) were caused by hot beverages, 25 (16%) hot water and 16 (10%) hot food stuffs. 97 (60%) presented within 1 hour of injury. 40 (25%) received first aid. The most affected areas were upper limbs 79 (35%) and upper trunk 74 (33%). Overall 45 (28%) were discharged home requiring no further treatment, 9 (6%) were admitted to hospital and 101 (63%) attended dressing clinic or plastic surgery OPD. Our results are consistent with other studies and illustrate that the incidence and pattern of scald injuries have not changed over the past decade. Scalds will continue to be a significant cause of unintentional injury and morbidity among young children unless preventative strategies are devised and employed.

Psychosocial challenges and protective influences for socio-emotional coping of HIV+ adolescents in South Africa: a qualitative investigation

INTRODUCTION

While the roll-out of antiretroviral therapy in South Africa should lead to a reduction in mother to child transmission, mortality and orphaning, it will also be accompanied by a large number of children entering adolescence and adulthood with a chronic infectious disease. Adolescence is a particularly vulnerable period for HIV-infected people in relation to mental health problems and engagement in high-risk behaviours, including non-compliance with medical treatment. The goal of this qualitative study was to develop an understanding of the psychosocial challenges as well as protective influences promoting socio-emotional coping in HIV+ adolescents in order to inform mental health promotion and HIV prevention programming for this population in South Africa.

METHOD

In-depth qualitative interviews were conducted with HIV+ adolescents (25) and caregivers of HIV+ children (15) at a large HIV/AIDS Clinic in South Africa. Data were analysed thematically using NVivo8 software.

RESULTS

Psycho-social challenges for adolescents included dealing with loss of biological parents in the case of orphans; coming to terms with their HIV+ status including identity difficulties; external stigma and discrimination; and disclosure difficulties. For caregivers, disclosure and lack of financial, family and social support emerged as key challenges. Medication, HIV information, a future orientation and social support was identified as important for coping and general well-being of adolescents, with financial and social support emerging as key for promoting supportive caregiving contexts.

CONCLUSION

While HIV+ adolescents in South Africa experience similar concerns to those in high-income countries, socio-emotional coping may be compromised by increased levels of loss due to the late roll-out of ARVS and challenges to caregiving contexts including poverty, stigma and minimally supported foster care arrangements. There is a need for mental health promotion programmes for adolescents to adopt an ecological approach, strengthening protective influences at the individual, interpersonal, community and policy levels.

Heading for a fall? Management of head injury in infants

Head injury is one of the commonest reasons for infants (< 1 year) to attend the Emergency Department (ED). Clinical management varies considerably and concern about non accidental injury results in a high admission rate in some hospitals. Information was obtained on 103 children under one year of age presenting to the ED with head injury in a prospective study. The average age was 6.7 months and 57% of patients were male. Twenty eight babies had skull x rays with 1 skull fracture diagnosed. None required CT brain scan. Ninety eight (94%) were discharged home from the ED. There were no unplanned returns, readmissions or adverse events. The incidence of traumatic brain injury in children under one year of age presenting with head injury is low and the majority can be safely discharged home.

Medical, social and societal issues in infants with abusive head trauma

Abusive head trauma (AHT) is the leading cause of death from traumatic brain injury in under 2 year olds. AHT presents with acute encephalopathy, subdural hemorrhages and retinal hemorrhages occurring in the context of an inappropriate or inconsistent history. We retrospectively analyzed, over a 10 year period, admissions and transfers to our hospital with suspected AHT to assess patterns of presentation, presenting symptoms, investigations, subsequent confirmation, social work input and both neurological and social outcomes. We analyzed all suspected AHT infants and children looking for the time of presentation, presenting symptoms, caregivers concerns prior to presentation, a family profile including stressors, investigations (in particular neuroradiology and ophthalmology assessments), treatment in hospital, length of stay in hospital, social work involvement, subsequent discharge, neurological outcome and subsequent social work follow up. Data was collected from the hospital HIPE system, RIS (radiology reports system) and records from the social work department from a period October 1998 to January 2009 inclusive. Of 22 patients with confirmed AHT, ages seizures and irritability followed by vomiting, poor feeding, a bulging fontanelle and lethargy. The father was the sole minder in 5 cases. There was a delayed history in 4 cases. One had multiple visits to his GP. All cases had subdural hemorrhages proven by either CT or MRI scans and retinal hemorrhages diagnosed by ophthalmology. One infant presented with a torn frenulum. Four had suspicious bruising. All had normal coagulation profiles, skeletal surveys and extensive metabolic tests. Hospital stays ranged from 1 to 124 days (the median was 28 days and mean 33 days). Ten (45%) infants required ventilatory support. Sixteen infants had social work involvement within 4 days of admission (7 of these were interviewed immediately). Outcomes after case conferences were that 6 returned home with parents, 9 were placed in foster care. Four parents (18%) admitted to shakng their infants. There was 1 death. Thirteen (60%) were normal on follow up. Two had ADHD. Two had language delay. Two had motor delay. One criminal prosecution has ensued as yet Children with suspected AHT should undergo appropriate investigations which should include brain imaging, ophthalmic examination, skeletal survey and blood investigations. Early social work assessment is a priority as part of the multidisciplinary approach. A prospective national study of AHT is required.

Switching from oral extended-release methylphenidate to the methylphenidate transdermal system: continued attention-deficit/hyperactivity disorder symptom control and tolerability after abrupt conversion

OBJECTIVE

To evaluate symptom control and tolerability after abrupt conversion from oral extended-release methylphenidate (ER-MPH) to methylphenidate transdermal system (MTS) via a dose-transition schedule in children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

In a 4-week, prospective, multisite, open-label study, 171 children (164 intent-to-treat) with diagnosed ADHD aged 6-12 years abruptly switched from a stable dose of oral ER-MPH to MTS in nominal dosages of 10, 15, 20, and 30 mg using a predefined dose-transition schedule. After the first week on the scheduled dose, the dose was titrated to optimal effect. The primary effectiveness outcome was the change from baseline (while taking ER-MPH) to week 4 in ADHD-Rating Scale-IV (ADHD-RS-IV) total scores. Adverse events (AEs) were assessed throughout the study.

RESULTS

Most subjects (58%) remained on the initial MTS dose defined by the dose-transition schedule; 38% increased and 4% decreased their MTS dose for optimization. MTS dose optimization resulted in significantly better ADHD-RS-IV total (mean +/- SD) scores at week 4 than at baseline (9.9 +/- 7.47 vs. 14.1 +/- 7.48; p < 0.0001). The most commonly reported AEs included headache, decreased appetite, insomnia, and upper abdominal pain. Four subjects (2.3%) discontinued because of application site reactions and three discontinued because of other AEs.

CONCLUSIONS

Abrupt conversion from a stable dose of oral ER-MPH to MTS was accomplished using a predefined dose-transition schedule without loss of symptom control; however, careful titration to optimal dose is recommended. Most AEs were mild to moderate and, with the exception of application site reactions, were similar to AEs typically observed with oral MPH. Limitations of this study included its open-label sequential design without placebo, which could result in spurious attribution of improvement to the study treatment and precluded superiority determinations of MTS over baseline ER-MPH treatment. The apparent superiority of MTS was likely due to more careful titration and clinical monitoring rather than the product itself. ClinicalTrials.gov: NCT00151983.

Heterogeneous nuclear ribonucleoprotein K is over expressed, aberrantly localised and is associated with poor prognosis in colorectal cancer

Heterogeneous ribonucleoprotein K (hnRNP K) is a member of the hnRNP family which has several different cellular roles including transcription, mRNA shuttling, RNA editing and translation. Several reports implicate hnRNP K having a role in tumorigenesis, for instance hnRNP K increases transcription of the oncogene c-myc and hnRNP K expression is regulated by the p53/MDM 2 pathway. In this study comparing normal colon to colorectal cancer by proteomics, hnRNP K was identified as being overexpressed in this type of cancer. Immunohistochemistry with a monoclonal antibody to hnRNP K (which we developed) on colorectal cancer tissue microarray, confirmed that hnRNP K was overexpressed in colorectal cancer (P<0.001) and also showed that hnRNP K had an aberrant subcellular localisation in cancer cells. In normal colon hnRNP K was exclusively nuclear whereas in colorectal cancer the protein localised both in the cytoplasm and the nucleus. There were significant increases in both nuclear (P=0.007) and cytoplasmic (P=0.001) expression of hnRNP K in Dukes C tumours compared with early stage tumours. In Dukes C patient's good survival was associated with increased hnRNP K nuclear expression (P=0.0093). To elaborate on the recent observation that hnRNP K is regulated by p53, the expression profiles of these two proteins were also analysed. There was no correlation between hnRNP K and p53 expression, however, patients who presented tumours that were positive for hnRNP K and p53 had a poorer survival outcome (P=0.045).

Anti-Human Leukocyte Antigen Antibodies are Associated with Restenosis after Percutaneous Coronary Intervention for Cardiac Allograft Vasculopathy

BACKGROUND

Percutaneous coronary intervention (PCI) to palliate cardiac allograft vasculopathy (CAV) has been associated with high restenosis rates, possibly related to increased inflammation associated with this disease. Whether markers of immunologic rejection are associated with restenosis in this population is unknown. The goal of the study was to determine the predictors of restenosis after PCI for CAV.

METHODS

Records were reviewed retrospectively from a single, high-volume cardiac transplant center. Clinical, angiographic, and immunologic data were collected on all patients postorthotopic heart transplantation (OHT) that had subsequent PCI. Restenosis was defined as greater than 50% stenosis at the previous intervention site.

RESULTS

PCI was successfully performed on 62 de novo lesions in 40 patients an average of 6.8+/-3.9 years after OHT. Angiographic follow-up data was available for 79%, with an average follow-up of 1.54+/-1.22 years. The 1-year restenosis rate was 49% (64% for balloon percutaneous transluminal coronary angioplasty and 33% for coronary stenting [P=0.09 for difference]). The frequency of immunoglobulin (Ig)G antibody to major histocompatibility complex (MHC) class I antigen was highly associated with risk of restenosis (hazard ratio [HR] 11.33, P=0.01). Greater stenosis severity and smaller target vessel diameter were also predictors of restenosis as in the nontransplant population.

CONCLUSIONS

The findings suggest that in patients postPCI for CAV, humoral allo-immunity may contribute to restenosis and that IgG antibodies to MHC class I antigen may help predict the risk of restenosis after PCI in this population.

Proteomic response of the biological control fungus Trichoderma atroviride to growth on the cell walls of Rhizoctonia solani

Trichoderma atroviride has a natural ability to parasitise phytopathogenic fungi such as Rhizoctonia solani and Botrytis cinerea, therefore providing an environmentally sound alternative to chemical fungicides in the management of these pathogens. Two-dimensional electrophoresis was used to display cellular protein patterns of T. atroviride (T. harzianum P1) grown on media containing either glucose or R. solani cell walls. Protein profiles were compared to identify T. atroviride proteins up-regulated in the presence of the R. solani cell walls. Twenty-four protein spots were identified using matrix-assisted laser desorption ionisation mass spectrometry, liquid chromatography mass spectrometry and N-terminal sequencing. Identified up-regulated proteins include known fungal cell wall-degrading enzymes such as N-acetyl-beta-D: -glucosaminidase and 42-kDa endochitinase. Three novel proteases of T. atroviride were identified, containing sequence similarity to vacuolar serine protease, vacuolar protease A and a trypsin-like protease from known fungal proteins. Eukaryotic initiation factor 4a, superoxide dismutase and a hypothetical protein from Neurospora crassa were also up-regulated as a response to R. solani cell walls. Several cell wall-degrading enzymes were identified from the T. atroviride culture supernatant, providing further evidence that a cellular response indicative of biological control had occurred.

Clinical and cellular radiosensitivity in inherited human syndromes

AIMS

It has been proposed that in-vitro measurements of radiosensitivity might allow individualisation of patient radiotherapy schedules, with concomitant increases in the therapeutic ratio between tumours and normal tissues. Most predictive assay research on normal tissues to date has been based on the radiosensitivity of normal lymphocytes and skin fibroblasts as determined by clonogenic cell-survival assays. Studies comparing the radiosensitivity of fibroblasts or lymphocytes with acute or late radiation damage have reported variable results.

METHODS

In this study, we measured the radiosensitivity of lymphocytes from three patients displaying clinical radiation hypersensitivity who were known or suspected to carry germline mutations in genes that have been linked to increased radiosensitivity (a BRCA2 mutation carrier, a patient with Bloom's syndrome and a patient with a Fanconi anaemia-like condition), to investigate whether there is a correlation between cellular radiosensitivity and normal tissue response.

RESULTS

We found no association between lymphocyte radiosensitivity and the development of adverse radiation reactions in this group of patients, as is observed in the paradigm radiosensitivity syndrome, ataxia-telangiectasia.

CONCLUSIONS

Our results, and those of others, show that, at present, the evidence is not strong enough to justify routine clinical use of clonogenic cell survival assays to predict radiation response.

Fungal proteomics: initial mapping of biological control strain Trichoderma harzianum

Trichoderma harzianum is a soil-borne filamentous fungus that exhibits biological control properties. T. harzianum can prevent the growth of pathogenic fungi on many types of plant crops, providing a chemically benign alternative to fungicidal agents currently on the market. A proteomic approach was taken to separate and identify proteins from a strain of T. harzianum with well established biocontrol properties. We developed a method of extracting proteins under acidic conditions that increased the solubilisation of alkaline proteins and eliminated acidic cell wall artefacts from micro-organisms in general. Combined with the use of protease inhibitors, this sample preparation method resulted in hundreds of proteins from T. harzianum being extracted and separated by two-dimensional gel electrophoresis. Proteins were identified by a combination of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry and liquid chromatography mass spectrometry (LC MS/MS). Manual de novo sequencing was conducted to obtain sequence tags on unidentified proteins. A total of 25 protein spots were positively identified from a whole-cell protein reference map of T. harzianum.