Neuroimmune signatures in chronic low back pain subtypes.

We recently showed that patients with different chronic pain conditions (such as chronic low back pain, fibromyalgia, migraine and Gulf War illness) demonstrated elevated brain and/or spinal cord levels of the glial marker 18-kDa translocator protein (TSPO), which suggests that neuroinflammation might be a pervasive phenomenon observable across multiple aetiologically heterogeneous pain disorders. Interestingly, the spatial distribution of this neuroinflammatory signal appears to exhibit a degree of disease specificity (e.g. with respect to the involvement of the primary somatosensory cortex), suggesting that different pain conditions may exhibit distinct 'neuroinflammatory signatures'. To explore this hypothesis further, we tested whether neuroinflammatory signal can characterize putative aetiological subtypes of chronic low back pain patients based on clinical presentation. Specifically, we explored neuroinflammation in patients whose chronic low back pain either did or did not radiate to the leg (i.e. 'radicular' versus 'axial' back pain). Fifty-four patients with chronic low back pain, 26 with axial back pain [43.7 ± 16.6 years old (mean ± SD)] and 28 with radicular back pain (48.3 ± 13.2 years old), underwent PET/MRI with 11C-PBR28, a second-generation radioligand for TSPO. 11C-PBR28 signal was quantified using standardized uptake values ratio (validated against volume of distribution ratio; n = 23). Functional MRI data were collected simultaneously to the 11C-PBR28 data (i) to functionally localize the primary somatosensory cortex back and leg subregions; and (ii) to perform functional connectivity analyses (in order to investigate possible neurophysiological correlations of the neuroinflammatory signal). PET and functional MRI measures were compared across groups, cross-correlated with one another and with the severity of 'fibromyalgianess' (i.e. the degree of pain centralization, or 'nociplastic pain'). Furthermore, statistical mediation models were used to explore possible causal relationships between these three variables. For the primary somatosensory cortex representation of back/leg, 11C-PBR28 PET signal and functional connectivity to the thalamus were: (i) higher in radicular compared to axial back pain patients; (ii) positively correlated with each other; (iii) positively correlated with fibromyalgianess scores, across groups; and finally (iv) fibromyalgianess mediated the association between 11C-PBR28 PET signal and primary somatosensory cortex-thalamus connectivity across groups. Our findings support the existence of 'neuroinflammatory signatures' that are accompanied by neurophysiological changes and correlate with clinical presentation (in particular, with the degree of nociplastic pain) in chronic pain patients. These signatures may contribute to the subtyping of distinct pain syndromes and also provide information about interindividual variability in neuroimmune brain signals, within diagnostic groups, that could eventually serve as targets for mechanism-based precision medicine approaches.

Is the 'never event' concept a useful safety management strategy in complex primary healthcare systems?

WHY IS THE AREA IMPORTANT?: A sub-group of rare but serious patient safety incidents, known as 'never events,' is judged to be 'avoidable.' There is growing interest in this concept in international care settings, including UK primary care. However, issues have been raised regarding the well-intentioned coupling of 'preventable harm' with zero tolerance 'never events,' especially around the lack of evidence for such harm ever being totally preventable. WHAT IS ALREADY KNOWN AND GAPS IN KNOWLEDGE?: We consider whether the ideal of reducing preventable harm to 'never' is better for patient safety than, for example, the goal of managing risk materializing into harm to 'as low as reasonably practicable,' which is well-established in other complex socio-technical systems and is demonstrably achievable.We reflect on the 'never event' concept in the primary care context specifically, although the issues and the polarized opinion highlighted are widely applicable. Recent developments to validate primary care 'never event' lists are summarized and alternative safety management strategies considered, e.g. Safety-I and Safety-II. FUTURE AREAS FOR ADVANCING RESEARCH AND PRACTICE: Despite their rarity, if there is to be a policy focus on 'never events,' then specialist training for key workforce members is necessary to enable examination of the complex system interactions and design issues, which contribute to such events. The 'never event' term is well intentioned but largely aspirational-however, it is important to question prevailing assumptions about how patient safety can be understood and improved by offering alternative ways of thinking about related complexities.

Quantitative PET in the 2020s: a roadmap.

Positron emission tomography (PET) plays an increasingly important role in research and clinical applications, catalysed by remarkable technical advances and a growing appreciation of the need for reliable, sensitive biomarkers of human function in health and disease. Over the last 30 years, a large amount of the physics and engineering effort in PET has been motivated by the dominant clinical application during that period, oncology. This has led to important developments such as PET/CT, whole-body PET, 3D PET, accelerated statistical image reconstruction, and time-of-flight PET. Despite impressive improvements in image quality as a result of these advances, the emphasis on static, semi-quantitative 'hot spot' imaging for oncologic applications has meant that the capability of PET to quantify biologically relevant parameters based on tracer kinetics has not been fully exploited. More recent advances, such as PET/MR and total-body PET, have opened up the ability to address a vast range of new research questions, from which a future expansion of applications and radiotracers appears highly likely. Many of these new applications and tracers will, at least initially, require quantitative analyses that more fully exploit the exquisite sensitivity of PET and the tracer principle on which it is based. It is also expected that they will require more sophisticated quantitative analysis methods than those that are currently available. At the same time, artificial intelligence is revolutionizing data analysis and impacting the relationship between the statistical quality of the acquired data and the information we can extract from the data. In this roadmap, leaders of the key sub-disciplines of the field identify the challenges and opportunities to be addressed over the next ten years that will enable PET to realise its full quantitative potential, initially in research laboratories and, ultimately, in clinical practice.

Content analysis of 50 clinical negligence claims involving test results management systems in general practice.

BACKGROUND AND AIMS: Laboratory test results management systems are a complex safety issue in primary care settings worldwide. Related failures lead to avoidable patient harm, medicolegal action, patient complaints and additional workload to problem solve identified issues. We aimed to review and learn from 50 clinical negligence cases involving system failures related to the management of test results. METHODS: The Medical Protection Society database was searched and a convenience sample of 50 claims identified from a 3-year period covering 2014-2016. A content analysis of documentation was undertaken to quantify and theme data, aided by a Risk Assessment Matrix and the Yorkshire Contributory Factors Framework. Quantitative data were subjected to simple descriptive statistical analysis. RESULTS: 14/50 cases (28%) involved a delay in diagnosis or treatment of a patient with cancer. 15 cases were judged to be 'never events' (30%) and 85 distinct system issues were identified. Just under half of cases involved a failure to notify patients of an abnormal test result (n=24, 48%), while 18 cases (36%) involved a test result not being actioned by a doctor. The most frequently occurring contributory factors (n=30, 60%) were related to local working conditions, for example, unclear professional responsibilities with regards to test result review or follow-up or lack of patient care continuity. CONCLUSION: This small study highlights why test result management systems fail and contribute to future litigation, providing new insights in this area. Most claims involved avoidable harm to patients and preventable organisational risks. The findings point to the inadequate design of practice systems and the need for proactive strategies to improve the management of test results in order to reduce patient harm.

Early striatal amyloid deposition distinguishes Down syndrome and autosomal dominant Alzheimer's disease from late-onset amyloid deposition.

INTRODUCTION: The objective of this study was to evaluate amyloid ß (Aß) deposition patterns in different groups of cerebral ß amyloidosis: (1) nondemented with amyloid precursor protein overproduction (Down syndrome); (2) nondemented with abnormal processing of amyloid precursor protein (preclinical autosomal dominant Alzheimer disease); (3) presumed alteration in Aß clearance with clinical symptoms (late-onset AD); and (4) presumed alterations in Aß clearance (preclinical AD). METHODS: We performed whole-brain voxelwise comparison of cerebral Aß between 23 Down syndrome, 10 preclinical autosomal dominant Alzheimer disease, 17 late-onset AD, and 16 preclinical AD subjects, using Pittsburgh Compound B-positron emission tomography. RESULTS: We found both Down syndrome and preclinical autosomal dominant Alzheimer disease shared a distinct pattern of increased bilateral striatal and thalamic Aß deposition compared to late-onset AD and preclinical AD. CONCLUSION: Disorders associated with early-life alterations in amyloid precursor protein production or processing are associated with a distinct pattern of early striatal fibrillary Aß deposition before significant cognitive impairment. A better understanding of this unique pattern could identify important mechanisms of Aß deposition and possibly important targets for early intervention.

Repeat prescribing of medications: A system-centred risk management model for primary care organisations.

RATIONALE, AIMS AND OBJECTIVES: Reducing preventable harm from repeat medication prescriptions is a patient safety priority worldwide. In the United Kingdom, repeat prescriptions items issued has doubled in the last 20 years from 5.8 to 13.3 items per patient per annum. This has significant resource implications and consequences for avoidable patient harms. Consequently, we aimed to test a risk management model to identify, measure, and reduce repeat prescribing system risks in primary care. METHODS: All 48 general medical practices in National Health Service (NHS) Lambeth Clinical Commissioning Group (an inner city area of south London in England) were recruited. Multiple interventions were implemented, including educational workshops, a web-based risk monitoring system, and external reviews of repeat prescribing system risks by clinicians. Data were collected via documentation reviews and interviews and subject to basic thematic and descriptive statistical analyses. RESULTS: Across the 48 participating general practices, 62 unique repeat prescribing risks were identified on 505 occasions (eg, practices frequently experiencing difficulty interpreting medication changes on hospital discharge summaries), equating to a mean of 8.1 risks per practice (range: 1-33; SD = 7.13). Seven hundred sixty-seven system improvement actions were recommended across 96 categories (eg, alerting hospitals to illegible writing and delays with discharge summaries) with a mean of 15.6 actions per practice (range: 0-34; SD = 8.0). CONCLUSIONS: The risk management model tested uncovered important safety concerns and facilitated the development and communication of related improvement recommendations. System-wide information on hazardous repeat prescribing and how this could be mitigated is very limited. The approach reported may have potential to close this gap and improve the reliability of general practice systems and patient safety, which should be of high interest to primary care organisations internationally.

Distress Screening and Management in an Outpatient VA Cancer Clinic: A Pilot Project Involving Ambulatory Patients Across the Disease Trajectory.

Screening all patients for distress addressed practical, psychosocial, physical, and spiritual needs does not seem to be burdensome for patients or providers at an outpatient cancer center.

Longitudinal assessment of neuroimaging and clinical markers in autosomal dominant Alzheimer's disease: a prospective cohort study.

BACKGROUND: The biomarker model of Alzheimer's disease postulates a dynamic sequence of amyloidosis, neurodegeneration, and cognitive decline as an individual progresses from preclinical Alzheimer's disease to dementia. Despite supportive evidence from cross-sectional studies, verification with long-term within-individual data is needed. METHODS: For this prospective cohort study, carriers of autosomal dominant Alzheimer's disease mutations (aged ≥21 years) were recruited from across the USA through referrals by physicians or from affected families. People with mutations in PSEN1, PSEN2, or APP were assessed at the University of Pittsburgh Alzheimer's Disease Research Center every 1-2 years, between March 23, 2003, and Aug 1, 2014. We measured global cerebral amyloid ß (Aß) load using (11)C-Pittsburgh Compound-B PET, posterior cortical metabolism with (18)F-fluorodeoxyglucose PET, hippocampal volume (age and sex corrected) with T1-weighted MRI, verbal memory with the ten-item Consortium to Establish a Registry for Alzheimer's Disease Word List Learning Delayed Recall Test, and general cognition with the Mini Mental State Examination. We estimated overall biomarker trajectories across estimated years from symptom onset using linear mixed models, and compared these estimates with cross-sectional data from cognitively normal control individuals (age 65-89 years) who were negative for amyloidosis, hypometabolism, and hippocampal atrophy. In the mutation carriers who had the longest follow-up, we examined the within-individual progression of amyloidosis, metabolism, hippocampal volume, and cognition to identify progressive within-individual changes (a significant change was defined as an increase or decrease of more than two Z scores standardised to controls). FINDINGS: 16 people with mutations in PSEN1, PSEN2, or APP, aged 28-56 years, completed between two and eight assessments (a total of 83 assessments) over 2-11 years. Significant differences in mutation carriers compared with controls (p<0·01) were detected in the following order: increased amyloidosis (7·5 years before expected onset), decreased metabolism (at time of expected onset), decreased hippocampal volume and verbal memory (7·5 years after expected onset), and decreased general cognition (10 years after expected onset). Among the seven participants with longest follow-up (seven or eight assessments spanning 6-11 years), three individuals had active amyloidosis without progressive neurodegeneration or cognitive decline, two amyloid-positive individuals showed progressive neurodegeneration and cognitive decline without further progressive amyloidosis, and two amyloid-positive individuals showed neither active amyloidosis nor progressive neurodegeneration or cognitive decline. INTERPRETATION: Our results support amyloidosis as the earliest component of the biomarker model in autosomal dominant Alzheimer's disease. Our within-individual examination suggests three sequential phases in the development of autosomal dominant Alzheimer's disease-active amyloidosis, a stable amyloid-positive period, and progressive neurodegeneration and cognitive decline-indicating that Aß accumulation is largely complete before progressive neurodegeneration and cognitive decline occur. These findings offer supportive evidence for efforts to target early Aß deposition for secondary prevention in individuals with autosomal dominant Alzheimer's disease. FUNDING: National Institutes of Health and Howard Hughes Medical Institute.

Frequency, characteristics, and correlates of pain in a pilot study of colorectal cancer survivors 1-10 years post-treatment.

OBJECTIVE: The long-term effects of disease and treatment in colorectal cancer (CRC) survivors are poorly understood. This study examined the prevalence and characteristics of pain in a sample of CRC survivors up to 10 years post-treatment. DESIGN: One hundred cancer-free CRC survivors were randomly chosen from an institutional database and completed a telephone survey using the Brief Pain Inventory, Neuropathic Pain Questionnaire-Short Form, Quality of Life Cancer Survivor Summary, Brief Zung Self-Rating Depression Scale, Zung Self-Rating Anxiety Scale, and Fear of Recurrence Questionnaire. RESULTS: Participants were primarily Caucasian (90%) married (69%) males (53.5%) with a mean age of 64.7 years. Chronic pain was reported in 23% of CRC survivors, with a mean moderate intensity rating (mean = 6.05, standard deviation = 2.66) on a 0-10 rating scale. Over one-third (39%) of those with pain attributed it to their cancer or treatment. Chi-square and t-test analyses showed that survivors with pain were more likely to be female, have lower income, be more depressed and more anxious, and show a higher endorsement of suicidal ideation than CRC survivors without chronic pain. On average, pain moderately interfered with daily activity. CONCLUSIONS: Chronic pain is likely a burdensome problem for a small but not inconsequential minority of CRC survivors requiring a biopsychosocial treatment approach to improve recognition and treatment. Open dialogue between clinicians and survivors about physical and emotional symptoms in long-term follow-up is highly recommended.

Classification of amyloid-positivity in controls: comparison of visual read and quantitative approaches.

UNLABELLED: An important research application of amyloid imaging with positron emission tomography (PET) is detection of the earliest evidence of fibrillar amyloid-beta (Aß) deposition. Use of amyloid PET for this purpose, requires a reproducible method for defining a cutoff that separates individuals with no significant Aß deposition from those in which Aß deposition has begun. We previously reported the iterative outlier approach (IO) for the analysis of Pittsburgh Compound-B (PiB) PET data. Developments in amyloid imaging since the initial report of IO have led us to re-examine the generalizability of this method. IO was developed using full-dynamic atrophy-corrected PiB PET data obtained from a group of control subjects with a fairly distinct separation between PiB-positive [PiB(+)] and PiB-negative [PiB(-)] subjects. METHODS: We tested the performance of IO using late-summed tissue ratio data with atrophy correction or with an automated template method without atrophy correction and tested the robustness of the method when applied to a cohort of older subjects in which separation between PiB(+) and PiB(-) subjects was not so distinct. RESULTS: The IO method did not perform consistently across analyses and performed particularly poorly when separation was less clear. We found that a sparse k-means (SKM) cluster analysis approach performed significantly better; performing more consistently across methods and subject cohorts. We also compared SKM to a consensus visual read approach and found very good correspondence. CONCLUSION: The visual read and SKM methods, applied together, may optimize the identification of early Aß deposition. These methods have the potential to provide a standard approach to the detection of PiB-positivity that is generalizable across centers.

Age, sex, and reproductive hormone effects on brain serotonin-1A and serotonin-2A receptor binding in a healthy population.

There is a need for rigorous positron emission tomography (PET) and endocrine methods to address inconsistencies in the literature regarding age, sex, and reproductive hormone effects on central serotonin (5HT) 1A and 2A receptor binding potential (BP). Healthy subjects (n=71), aged 20-80 years, underwent 5HT1A and 2A receptor imaging using consecutive 90-min PET acquisitions with [(11)C]WAY100635 and [(18)F]altanserin. Logan graphical analysis was used to derive BP using atrophy-corrected distribution volume (V(T)) in prefrontal, mesiotemporal, occipital cortices, and raphe nucleus (5HT1A only). We used multivariate linear regression modeling to examine BP relationships with age, age(2), sex, and hormone concentrations, with post hoc regional significance set at p<0.008. There were small postsynaptic 5HT1A receptor BP increases with age and estradiol concentration in women (p=0.004-0.005) and a tendency for small 5HT1A receptor BP declines with age and free androgen index in men (p=0.05-0.06). Raphe 5HT1A receptor BP decreased 4.5% per decade of age (p=0.05), primarily in men. There was a trend for 15% receptor reductions in prefrontal cortical regions in women relative to men (post hoc p=0.03-0.10). The significant decline in 5HT2A receptor BP relative to age (8% per decade; p<0.001) was not related to sex or hormone concentrations. In conclusion, endocrine standardization minimized confounding introduced by endogenous hormonal fluctuations and reproductive stage and permitted us to detect small effects of sex, age, and endogenous sex steroid exposures upon 5HT1A binding. Reduced prefrontal cortical 5HT1A receptor BP in women vs men, but increased 5HT1A receptor BP with aging in women, may partially explain the increased susceptibility to affective disorders in women during their reproductive years that is mitigated in later life. 5HT1A receptor decreases with age in men might contribute to the known increased risk for suicide in men over age 75 years. Low hormone concentrations in adults <50 years of age may be associated with more extreme 5HT1A receptor BP values, but remains to be studied further. The 5HT2A receptor declines with age were not related to sex or hormone concentrations in this sample. Additional study in clinical populations is needed to further examine the affective role of sex-hormone-serotonin receptor relationships.

Adjuvant therapy in non-small cell lung cancer: current and future directions.

The cornerstone of treatment for early-stage non-small cell lung cancer (NSCLC) has long been surgical resection. Over the past few years, there has been a paradigm shift to provide adjuvant platinum-based chemotherapy for patients with completely resected stage II-IIIA NSCLC founded on large randomized clinical trials demonstrating longer overall survival with this treatment. Reassuringly, the National Cancer Institute of Canada Cancer Therapeutics Group JBR.10 trial recently reported a continued survival advantage for patients treated with adjuvant chemotherapy after >9 years of median follow-up. In contrast, the gains from using this approach for stage IB disease are less clear, although data from an unplanned subgroup analysis suggest benefit for patients with tumors > or = 4 cm. Herein, we review the evidence supporting adjuvant therapy in early-stage NSCLC patients before discussing key mitigating factors in providing treatment, such as stage of disease and the impact of the new seventh edition of the tumor-node-metastasis classification system. Criteria such as patient age and performance status, as well as the value of appropriate chemotherapy selection, are highlighted as measures to help guide management. The role of postoperative radiotherapy and the future landscape of early-stage NSCLC research are also explored; namely, therapeutic strategies exploiting pharmacogenomic and gene-expression profiling, in an attempt to personalize care, and the integration of novel targeted therapies into adjuvant clinical trials.

Carbon 11-labeled Pittsburgh Compound B and carbon 11-labeled (R)-PK11195 positron emission tomographic imaging in Alzheimer disease.

BACKGROUND: Alzheimer disease (AD) is defined neuropathologically by the presence of neurofibrillary tangles and plaques associated with tau and beta-amyloid protein deposition. The colocalization of microglia and beta-amyloid plaques has been widely reported in pathological examination of AD and suggests that neuroinflammation may play a role in pathogenesis and/or progression. Because postmortem histopathological analyses are limited to single end-stage assessment, the time course and nature of this relationship are not well understood. OBJECTIVE: To image microglial activation and beta-amyloid deposition in the brains of subjects with and without AD. DESIGN, SETTING, AND PARTICIPANTS: Using two carbon 11 ([11C])-labeled positron emission tomographic imaging agents, Pittsburgh Compound B (PiB) and (R)-PK11195, we examined the relationship between amyloid deposition and microglial activation in different stages of AD using 5 control subjects, 6 subjects diagnosed with mild cognitive impairment, and 6 patients with mild to moderate AD. RESULTS: Consistent with prior reports, subjects with a clinical diagnosis of probable AD showed significantly greater levels of [11C]PiB retention than control subjects, whereas patients with mild cognitive impairment spanned a range from control-like to AD-like levels of [11C]PiB retention. Additionally, 2 asymptomatic control subjects also exhibited evidence of elevated PiB retention in regions associated with the early emergence of plaques in AD and may represent prodromal cases of AD. We observed no differences in brain [11C](R)-PK11195 retention when subjects were grouped by clinical diagnosis or the presence or absence of beta-amyloid pathological findings as indicated by analyses of [11C]PiB retention. CONCLUSIONS: These findings suggest that either microglial activation is limited to later stages of severe AD or [11C](R)-PK11195 is too insensitive to detect the level of microglial activation associated with mild to moderate AD.

Serotonin 1A receptor reductions in postpartum depression: a positron emission tomography study.

OBJECTIVE: To measure brain serotonin-1A (5HT1A) receptor binding potential (BP) in healthy and depressed postpartum women. DESIGN: 5HT1A receptor BP was measured with positron emission tomography by using [(11)C]WAY100635 a single time. Multivariate analysis of variance was used to determine depression effects on 5HT1A receptor BP in relevant brain regions. SETTING: An academic research environment. PATIENT(S): Seven postpartum healthy controls and nine postpartum depressed (PD) subjects with perinatal (antepartum or postpartum) depression onset. Of the nine PD subjects, five had unipolar depression, and four had bipolar disorder. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): 5HT1A receptor BP. RESULT(S): Age, time since delivery, and reproductive hormones did not differ between groups. Postsynaptic 5HT1A receptor binding in postpartum depression was reduced 20%-28% relative to controls, with most significant reductions in anterior cingulate and mesiotemporal cortices. CONCLUSION(S): Postsynaptic 5HT1A receptor binding is reduced in PD women by a similar magnitude as has been shown in other depression samples. The postpartum hormonal milieu and the large proportion of bipolar spectrum subjects in the PD group may have accentuated this finding in this small sample. Recognition of this neurobiological deficit in postpartum depression may be useful in the development of treatments and prevention strategies for this disabling disorder.

Imaging of amyloid burden and distribution in cerebral amyloid angiopathy.

OBJECTIVE: Cerebrovascular deposition of beta-amyloid (cerebral amyloid angiopathy [CAA]) is a major cause of hemorrhagic stroke and a likely contributor to vascular cognitive impairment. We evaluated positron emission tomographic imaging with the beta-amyloid-binding compound Pittsburgh Compound B (PiB) as a potential noninvasive method for detection of CAA. We hypothesized that amyloid deposition would be observed with PiB in CAA, and based on the occipital predilection of CAA pathology and associated hemorrhages, that specific PiB retention would be disproportionately greater in occipital lobes. METHODS: We compared specific cortical PiB retention in 6 nondemented subjects diagnosed with probable CAA with 15 healthy control subjects and 9 patients with probable Alzheimer's disease (AD). RESULTS: All CAA and AD subjects were PiB-positive, both by distribution volume ratio measurements and by visual inspection of positron emission tomographic images. Global cortical PiB retention was significantly increased in CAA (distribution volume ratio 1.18 +/- 0.06) relative to healthy control subjects (1.04 +/- 0.10; p = 0.0009), but was lower in CAA than in AD subjects (1.41 +/- 0.17; p = 0.002). The occipital-to-global PiB ratio, however, was significantly greater in CAA than in AD subjects (0.99 +/- 0.07 vs 0.86 +/- 0.05; p = 0.003). INTERPRETATION: We conclude that PiB-positron emission tomography can detect cerebrovascular beta-amyloid and may serve as a method for identifying the extent of CAA in living subjects.

Role of cyclic-AMP responsive element binding (CREB) proteins in cell proliferation in a rat model of hepatocellular carcinoma.

The role of cyclic adenosine monophosphate (cAMP) is poorly understood in the regulation of normal and abnormal hepatic cell growth. In this study, we examined the regulation of intracellular cAMP levels and its effect on nuclear cAMP responsive elements (CREs) in a rat model of hepatocellular carcinoma (HCC). Tumorigenic liver cells were cultured from an in vivo model of HCC and the role of cAMP in cell mitogenesis determined. These data demonstrated agents that elevate intracellular cAMP ([cAMP]i) levels caused significant dose-dependent inhibition of serum-stimulated mitogenesis in HCC cells. Cells were next analyzed for transcription factor expression and activity following increased [cAMP]i. These data demonstrated time- and dose-dependent increases in CRE binding protein (pCREB) activity, a maximal response occurring after 10-20 min before returning to basal levels within 60 min. In contrast, increased [cAMP]i levels led to sustained inducible cAMP early repressor (ICER) II/IIgamma mRNA and protein induction. To understand these data in relation to the in vivo setting, HCC tumors were analyzed and compared to pair-matched normal liver (NL) samples. These studies demonstrated significantly elevated Gsalpha-protein expression in HCC versus NL in the absence of significant changes in basal cAMP levels. Analysis of total and active CREB demonstrated significantly increased total CREB/pCREB in HCC versus NL. Further analysis of CRE expression demonstrated significantly increased expression of ICER mRNA and protein in HCC versus sham operated (Sh). These data demonstrate cAMP, while capable of stimulating promitogenic CREB activation inhibits cell mitogenesis in HCC possibly via ICER induction.

Radical radiotherapy for cervix cancer: the effect of waiting time on outcome.

PURPOSE: To assess the effect of treatment waiting time on clinical outcome for patients with cervix cancers treated with radical radiotherapy. METHODS AND MATERIALS: A retrospective analysis was conducted on all cervix cancer patients treated with radical radiotherapy between 1990 and 2001 at the Ottawa Regional Cancer Centre. Analyses were performed according to the three following separate definitions of waiting times: interval from start of radiotherapy to (1) date of initial biopsy, (2) date of examination under anesthesia, and (3) date of radiation oncology consultation. Associations between waiting times and patient characteristics and disease control were investigated using t-tests, analyses of variance, and Cox regression analyses. RESULTS: A total of 195 patients were studied. The vast majority of patients were treated within 5, 6, and 8 weeks of their consultation (91%), examination under anesthesia (88%), and biopsy (81%), respectively. On average, delays between initial biopsy and treatment start were greater for older patients (p = 0.025) (5.8 weeks for <40 years old vs. 6.6 weeks for >70 years old) and those with smaller tumors (p < 0.001) (5.0 weeks for >4 cm vs. 6.3 weeks for < or =4 cm). Univariate analysis revealed no adverse effect of treatment delay on tumor control. Multivariate analysis, with the inclusion of multiple prognostic tumor and treatment parameters, revealed an adverse effect of treatment delay on survival outcomes. CONCLUSIONS: Longer radiotherapy waiting times were found to be associated with diminished survival outcomes for patients treated radically for cervix cancer. The significance of this observed association requires further investigation.

Insulin-like growth factor I is a comitogen for hepatocyte growth factor in a rat model of hepatocellular carcinoma.

Hepatocyte growth factor-scatter factor (HGF-SF) is a potent hepatic mitogen yet inhibits hepatocellular carcinoma (HCC) cell growth in vitro. Insulin-like growth factor I (IGF-I) is a pleiotropic growth factor shown to be important in cell growth and differentiation in other tumors. We hypothesized that IGF-I may play a role in regulating HGF-SF activity and HCC progression. Using an in vivo model of HCC, we showed elevated IGF-I messenger RNA (mRNA) expression in normal liver from tumor-burdened animals in the absence of changes in circulating IGF-I levels. Analysis of IGF-I receptor (IGF-IR) and HGF-SF (c-met) receptor expression showed significantly higher expression of both receptors in normal liver compared with an HCC specimen. Using cultured HCC cells from this model, we next showed that treatment with IGF-I led to significant increases in mitogen-activated protein kinase (MAPK) activity. Furthermore, we observed significant time-dependent increases in the expression of the c-fos and c-jun proto-oncogenes after addition of IGF-I (n = 5 per group, P <.05). Despite activation of a MAPK pathway and increased proto-oncogene expression, IGF-I failed to significantly affect cell mitogenesis. In contrast, HGF significantly inhibited cell mitogenesis in HCC lines (68.4% +/- 9.4% vs. control, n = 4, P <.05). Pretreatment of HCC cells with IGF-I (60 minutes) led to significant HGF-SF stimulation of total cell mitogenesis dependent on both IGF-I and HGF-SF dose (194% +/- 8% increase vs. control, n = 4, P <.05). In conclusion, tumor burden is important in altering intrahepatic growth factor synthesis. Signal cooperation between multiple cytokine pathways is an important factor in the progression of HCC.