Mesothelin antigen density influences anti-mesothelin chimeric antigen receptor T cell cytotoxicity

BACKGROUND AIMS

Several anti-mesothelin (MSLN) chimeric antigen receptor (CAR) T cells are in phase 1/2 clinical trials to treat solid-organ malignancies. The effect of MSLN antigen density on MSLN CAR cytotoxicity against tumor cells has not been examined previously, nor are there data regarding the effect of agents that increase MSLN antigen density on anti-MSLN CAR T cell efficacy.

METHODS

MSLN antigen density was measured on a panel of pancreatic cancer and mesothelioma cell lines by flow cytometry. In parallel, the cytotoxicity and specificity of two anti-MSLN CAR T cells (m912 and SS1) were compared against these cell lines using a real-time impedance-based assay. The effect of two MSLN 'sheddase' inhibitors (lanabecestat and TMI-1) that increase MSLN surface expression was also tested in combination with CAR T cells.

RESULTS

SS1 CAR T cells were more cytotoxic compared with m912 CAR T cells against cell lines that expressed fewer than ∼170 000 MSLN molecules/cell. A comparison of the m912 and amatuximab (humanized SS1) antibodies identified that amatuximab could detect and bind to lower levels of MSLN on pancreatic cancer and mesothelioma cell lines, suggesting that superior antibody/scFv affinity was the reason for the SS1 CAR's superior cytotoxicity. The cytotoxicity of m912 CAR T cells was improved in the presence of sheddase inhibitors, which increased MSLN antigen density.

CONCLUSIONS

These data highlight the value of assessing CAR constructs against a panel of cells expressing varying degrees of target tumor antigen as occurs in human tumors. Furthermore, the problem of low antigen density may be overcome by concomitant administration of drugs that inhibit enzymatic shedding of MSLN.

12 The incidence, clinical features, and management of essential infantile esotropia in the United Kingdom. A British Ophthalmology Surveillance Unit (BOSU) study - Final Report

Studies from the UK have reported declining rates of surgery for childhood esotropia. It is not known if this equates to a reduced incidence of essential infantile esotropia (EIE). A national study was undertaken through the British ophthalmology surveillance unit (BOSU) to determine the incidence presenting features and management of EIE in the UKData from a prospective national observational cohort of newly diagnosed EIE presenting to clinicians in the United Kingdom over a 12-month period was collected. Cases with a confirmed diagnosis by a clinician of a constant, non-accommodative esotropia ≥ 20 prism dioptres (PD), presenting at ≤ 12months, with no neurological or ocular abnormalities were identified through BOSU. Follow up data was collected at 12 months. Data was collected on the age, gender, ethnicity, birth history, age at diagnosis, age at intervention, angle of esotropia, refraction, associated features of amblyopia, overelevation in adduction (OEIA), latent nystagmus and dissociated vertical deviation (DVD), method of management and outcomes.During the period of observation between October 2017 to October 2018 a total of 57 cases were reported giving an incidence of EIE of 1 in 12,828 live births with a corrected incidence of 1 in 9027 live births allowing for estimated under reporting. The mean age of diagnosis and intervention were 7.05± 2.6 months (range 2 to 12 months) and 14.7± 4.9 (range 6.5-28.1 months) respectively. The majority were Caucasians 86.5% and 52.7% were female. Management was surgical in 59.6%, and botulinum toxin alone in 22.8%, 17.5% were observed. There was no significant difference in the age of presentation (P=0.6), gender (P=0.8), prematurity (P=0.5), deprivation indices (P=0.68), refraction (P=0.7), OEIA (P=0.6), DVD (P=0.7) or follow up (P=0.3) between the three groups. The preoperative angle of esotropia was smaller in the observation group (P=0.04). The post-operative angle of esotropia was not statistically significant between botulinum toxin or surgery (P=0.3) though the age of intervention was earlier in the botulinum group (P=0.007). Early intervention did not influence the motor post intervention outcomes between 0-10 prism dioptres of esotropia (P=0.78). Amblyopia (P=0.02) and latent nystagmus (P=0.009) was more common in the observation group.The incidence of EIE in the UK is considerably lower than reported in other population-based studies. The preferred method of treatment was surgical with earlier intervention in those treated with botulinum toxin. An early age of intervention did not influence motor outcomes. Parental choice and amblyopia treatment were reasons cited for conservative management in the observational group.

High mesothelin expression by immunohistochemistry predicts improved survival in pleural mesothelioma

AIMS

Mesothelin (MSLN) is a cancer-associated antigen that is overexpressed in malignancies such as mesothelioma, pancreatic and ovarian cancer. It is also a target for novel personalised therapies, including antibodies, antibody-drug conjugates and chimeric antigen receptor T cells. Immunohistochemistry may predict those who would best respond to anti-mesothelin therapies and guide decisions in therapeutic strategy. This study aimed to assess the intensity and distribution of MSLN immunostaining in mesothelioma, and to determine the prognostic value of MSLN expression by histochemical-score (H-score).

METHODS AND RESULTS

The MN1 anti-MSLN antibody was used to stain a formalin-fixed paraffin-embedded tissue microarray of histologically confirmed mesothelioma from 75 consecutive patients who had undergone pleurectomy with or without decortication. MSLN positivity, the staining intensity, distribution of staining and H-score were evaluated. The correlation of H-score with prognosis was investigated. Sixty-six per cent of epithelioid tumours were MSLN-positive (with expression in > 5% tumour cells). Of MSLN-expressing epithelioid tumours, 70.4% had moderate (2+) or strong (3+) intensity MSLN immunostaining, although only 37% of samples had staining in ≥ 50% of tumour cells. In multivariate analysis, MSLN H-score as a continuous variable and an H-score ≥ 33 were independent predictors of improved survival (P = 0.04 and P < 0.001, respectively).

CONCLUSIONS

MSLN expression was more heterogenous in epithelioid mesothelioma than reported previously. Therefore, it would be appropriate to perform an immunohistochemical assessment of MSLN expression to stratify and assess patient suitability for mesothelin-targeted personalised therapies, such as chimeric antigen receptor T cells.

Accurate isolation and detection of circulating tumor cells using enrichment-free multiparametric high resolution imaging

Introduction

The reliable and accurate detection of rare circulating tumor cells (CTCs) from cancer patient blood samples promises advantages in both research and clinical applications. Numerous CTC detection methods have been explored that rely on either the physical properties of CTCs such as density, size, charge, and/or their antigen expression profiles. Multiple factors can influence CTC recovery including blood processing method and time to processing. This study aimed to examine the accuracy and sensitivity of an enrichment-free method of isolating leukocytes (AccuCyte® system) followed by immunofluorescence staining and high-resolution imaging (CyteFinder® instrument) to detect CTCs.

Method

Healthy human blood samples, spiked with cancer cells from cancer cell lines, as well as blood samples obtained from 4 subjects diagnosed with cancer (2 pancreatic, 1 thyroid, and 1 small cell lung) were processed using the AccuCyte-CyteFinder system to assess recovery rate, accuracy, and reliability over a range of processing times.

Results

The AccuCyte-CyteFinder system was highly accurate (95.0%) at identifying cancer cells in spiked-in samples (in 7.5 mL of blood), even at low spiked-in numbers of 5 cells with high sensitivity (90%). The AccuCyte-CyteFinder recovery rate (90.9%) was significantly higher compared to recovery rates obtained by density gradient centrifugation (20.0%) and red blood cell lysis (52.0%). Reliable and comparable recovery was observed in spiked-in samples and in clinical blood samples processed up to 72 hours post-collection. Reviewer analysis of images from spiked-in and clinical samples resulted in high concordance (R-squared value of 0.998 and 0.984 respectively).

Discussion

The AccuCyte-CyteFinder system is as an accurate, sensitive, and clinically practical method to detect and enumerate cancer cells. This system addresses some of the practical logistical challenges in incorporating CTCs as part of routine clinical care. This could facilitate the clinical use of CTCs in guiding precision, personalized medicine.

Locoregional delivery of CAR-T cells in the clinic

Cellular therapies utilizing T cells expressing chimeric antigen receptors (CARs) have garnered significant interest due to their clinical success in hematological malignancies. Unfortunately, this success has not been replicated in solid tumors, with only a small fraction of patients achieving complete responses. A number of obstacles to effective CAR-T cell therapy in solid tumors have been identified including tumor antigen heterogeneity, poor T cell fitness and persistence, inefficient trafficking and inability to penetrate into the tumor, immune-related adverse events due to on-target/off-tumor toxicity, and the immunosuppressive tumor microenvironment. Many preclinical studies have focused on improvements to CAR design to try to overcome some of these hurdles. However, a growing body of work has also focused on the use of local and/or regional delivery of CAR-T cells as a means to overcome poor T cell trafficking and inefficient T cell penetration into tumors. Most trials that incorporate locoregional delivery of CAR-T cells have targeted tumors of the central nervous system - repurposing an Ommaya/Rickham reservoir for repeated delivery of cells directly to the tumor cavity or ventricles. Hepatic artery infusion is another technique used for locoregional delivery to hepatic tumors. Locoregional delivery theoretically permits increased numbers of CAR-T cells within the tumor while reducing the risk of immune-related systemic toxicity. Studies to date have been almost exclusively phase I. The growing body of evidence indicates that locoregional delivery of CAR-T cells is both safe and feasible. This review focuses specifically on the use of locoregional delivery of CAR-T cells in clinical trials.

The next wave of cellular immunotherapies in pancreatic cancer

Pancreatic cancer is an aggressive disease that is predicted to become the second leading cause of cancer-related death worldwide by 2030. The overall 5-year survival rate is around 10%. Pancreatic cancer typically presents late with locally advanced or metastatic disease, and there are limited effective treatments available. Cellular immunotherapy, such as chimeric antigen receptor (CAR) T cell therapy, has had significant success in treating hematological malignancies. However, CAR T cell therapy efficacy in pancreatic cancer has been limited. This review provides an overview of current and ongoing CAR T cell clinical studies of pancreatic cancer and the major challenges and strategies to improve CAR T cell efficacy. These strategies include arming CAR T cells; developing off-the-shelf allogeneic CAR T cells; using other immune CAR cells, like natural killer cells and tumor-infiltrating lymphocytes; and combination therapy. Careful incorporation of preclinical models will enhance management of affected individuals, assisting incorporation of cellular immunotherapies. A multifaceted, personalized approach involving cellular immunotherapy treatment is required to improve pancreatic cancer outcomes.

Mapping oncogenic protein interactions for precision medicine

Normal protein‐protein interactions (normPPIs) occur with high fidelity to regulate almost every physiological process. In cancer, this highly organised and precisely regulated network is disrupted, hijacked or reprogrammed resulting in oncogenic protein‐protein interactions (oncoPPIs). OncoPPIs, which can result from genomic alterations, are a hallmark of many types of cancers. Recent technological advances in the field of mass spectrometry (MS)‐based interactomics, structural biology and drug discovery have prompted scientists to identify and characterise oncoPPIs. Disruption of oncoPPI interfaces has become a major focus of drug discovery programs and has resulted in the use of PPI‐specific drugs clinically. However, due to several technical hurdles, studies to build a reference oncoPPI map for various cancer types have not been undertaken. Therefore, there is an urgent need for experimental workflows to overcome the existing challenges in studying oncoPPIs in various cancers and to build comprehensive reference maps. Here, we discuss the important hurdles for characterising oncoPPIs and propose a three‐phase multidisciplinary workflow to identify and characterise oncoPPIs. Systematic identification of cancer‐type‐specific oncogenic interactions will spur new opportunities for PPI‐focused drug discovery projects and precision medicine.

Echocardiographic global longitudinal strain as a marker of myocardial fibrosis predicts outcomes in aortic stenosis

Background

Left ventricular global longitudinal strain (LV-GLS) by speckle tracking echocardiography (STE) reflects intrinsic myocardial function, influenced by interstitial abnormalities. Cardiovascular magnetic resonance (CMR) detects myocardial fibrosis non-invasively, but it is limited for widespread use. We aim to establish LV-GLS as a marker of replacement myocardial fibrosis on CMR and validate the prognostic value of LV-GLS thresholds associated with fibrosis.

Methods

LV-GLS thresholds of replacement fibrosis were established in the derivation cohort: 151 patients (57±10 years; 58% males) with hypertension who underwent STE to measure LV-GLS and CMR for replacement myocardial fibrosis. Prognostic value of the thresholds was validated in a separate outcome cohort: 261 patients with moderate-severe aortic stenosis (AS; 71±12 years; 58% males; NYHA functional class I-II) and preserved LVEF ≥50%. Primary outcome was a composite of cardiovascular mortality, heart failure hospitalization, myocardial infarction and cerebrovascular events.

Results

In the derivation cohort, LV-GLS demonstrated good discrimination (c-statistics 0.74; 95% confidence interval: 0.66–0.83; P&lt;0.001) and calibration (Hosmer-Lemeshow X2=6.37; P=0.605) for replacement fibrosis. In the outcome cohort, 52 events occurred over 16 [3.1, 42.0] months of follow-up. Patients with LV-GLS &gt;−15.0% (corresponding to 95% specificity to rule-in myocardial fibrosis) had the worst outcomes compared to patients with LV-GLS &lt;−21.0% (corresponding to 95% sensitivity to rule-out myocardial fibrosis) and those between −21.0 and −15.0% (log-rank P&lt;0.001; Figure 1). Furthermore, LV-GLS offered independent prognostic value over clinical variables, AS severity, echocardiographic LVEF and E/e' (hazard ratio 1.18; 95% confidence interval: 1.07 to 1.30; P=0.001).

Conclusions

LV-GLS thresholds associated with replacement myocardial fibrosis is a novel approach to risk-stratify patients with AS and preserved LVEF (Figure 2).

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Medical Research Council Figure 1Figure 2

Hitting the Bull's-Eye: Mesothelin's Role as a Biomarker and Therapeutic Target for Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is an aggressive cancer with limited treatment options and poor prognosis. MPM originates from the mesothelial lining of the pleura. Mesothelin (MSLN) is a glycoprotein expressed at low levels in normal tissues and at high levels in MPM. Many other solid cancers overexpress MSLN, and this is associated with worse survival rates. However, this association has not been found in MPM, and the exact biological role of MSLN in MPM requires further exploration. Here, we discuss the current research on the diagnostic and prognostic value of MSLN in MPM patients. Furthermore, MSLN has become an attractive immunotherapy target in MPM, where better treatment strategies are urgently needed. Several MSLN-targeted monoclonal antibodies, antibody-drug conjugates, immunotoxins, cancer vaccines, and cellular therapies have been tested in the clinical setting. The biological rationale underpinning MSLN-targeted immunotherapies and their potential to improve MPM patient outcomes are reviewed.

The impact of impulsivity on weight loss after bariatric surgery: a systematic review

BACKGROUND

Impulsivity has been shown to be associated with obesity through links to pathological eating behavior such as binge eating. The recent literature suggests that impulsivity is linked to poorer outcomes post-bariatric surgery. Impulsivity can be measured in various ways and comprises of three broad domains: impulsive choice, impulsive action, and impulsive personality traits. The aim of this systematic review is to synthesize the current evidence on the impact of impulsivity on post-bariatric surgery weight loss.

METHODS

A literature review was performed in February 2020. Original studies investigating the relationship between impulsivity and weight loss post-bariatric surgery were evaluated.

RESULTS

Ten studies with a total of 1246 patients were analyzed. There were four case-control, four prospective observational and two retrospective observational studies. The postoperative follow-up ranged from 0.5 to 12 years. Eight studies measuring trait impulsivity did not show any association with weight loss post-bariatric surgery, although two studies reported an indirect effect of impulsivity on weight loss mediated via pathological eating behavior. Assessment of impulsive action by two studies showed that post-bariatric surgery weight loss is affected by impulsive action.

CONCLUSION

Impulsivity may adversely affect postoperative outcomes after bariatric surgery. However, this may be specific to state impulsivity or impulsive action rather than trait impulsivity. Patients with a higher state impulsivity may benefit from closer follow-up post-bariatric surgery, as well as cognitive behavioral therapies targeting cognitive control over food.

LEVEL OF EVIDENCE

Level I, systematic review.

Anti-Mesothelin CAR T cell therapy for malignant mesothelioma

Malignant mesothelioma (MM) is a treatment-resistant tumor originating in the mesothelial lining of the pleura or the abdominal cavity with very limited treatment options. More effective therapeutic approaches are urgently needed to improve the poor prognosis of MM patients. Chimeric Antigen Receptor (CAR) T cell therapy has emerged as a novel potential treatment for this incurable solid tumor. The tumor-associated antigen mesothelin (MSLN) is an attractive target for cell therapy in MM, as this antigen is expressed at high levels in the diseased pleura or peritoneum in the majority of MM patients and not (or very modestly) present in healthy tissues. Clinical trials using anti-MSLN CAR T cells in MM have shown that this potential therapeutic is relatively safe. However, efficacy remains modest, likely due to the MM tumor microenvironment (TME), which creates strong immunosuppressive conditions and thus reduces anti-MSLN CAR T cell tumor infiltration, efficacy and persistence. Various approaches to overcome these challenges are reviewed here. They include local (intratumoral) delivery of anti-MSLN CAR T cells, improved CAR design and co-stimulation, and measures to avoid T cell exhaustion. Combination therapies with checkpoint inhibitors as well as oncolytic viruses are also discussed. Preclinical studies have confirmed that increased efficacy of anti-MSLN CAR T cells is within reach and offer hope that this form of cellular immunotherapy may soon improve the prognosis of MM patients.

A Deep Learning-Based Approach to Reduce Rescan and Recall Rates in Clinical MRI Examinations

BACKGROUND AND PURPOSE

MR imaging rescans and recalls can create large hospital revenue loss. The purpose of this study was to develop a fast, automated method for assessing rescan need in motion-corrupted brain series.

MATERIALS AND METHODS

A deep learning-based approach was developed, outputting a probability for a series to be clinically useful. Comparison of this per-series probability with a threshold, which can depend on scan indication and reading radiologist, determines whether a series needs to be rescanned. The deep learning classification performance was compared with that of 4 technologists and 5 radiologists in 49 test series with low and moderate motion artifacts. These series were assumed to be scanned for 2 scan indications: screening for multiple sclerosis and stroke.

RESULTS

The image-quality rating was found to be scan indication- and reading radiologist-dependent. Of the 49 test datasets, technologists created a mean ratio of rescans/recalls of (4.7 ± 5.1)/(9.5 ± 6.8) for MS and (8.6 ± 7.7)/(1.6 ± 1.9) for stroke. With thresholds adapted for scan indication and reading radiologist, deep learning created a rescan/recall ratio of (7.3 ± 2.2)/(3.2 ± 2.5) for MS, and (3.6 ± 1.5)/(2.8 ± 1.6) for stroke. Due to the large variability in the technologists' assessments, it was only the decrease in the recall rate for MS, for which the deep learning algorithm was trained, that was statistically significant (P = .03).

CONCLUSIONS

Fast, automated deep learning-based image-quality rating can decrease rescan and recall rates, while rendering them technologist-independent. It was estimated that decreasing rescans and recalls from the technologists' values to the values of deep learning could save hospitals $24,000/scanner/year.

Inhibition of group 1 p21-activated kinases suppresses pancreatic stellate cell activation and increases survival of mice with pancreatic cancer

Pancreatic cancer remains one of the most lethal of all solid tumors. Pancreatic stellate cells (PSCs) are primarily responsible for the fibrosis that constitutes the stroma and p21-activated kinase 1 (PAK1) may have a role in signalling pathways involving PSCs. This study aimed to examine the role of PAK1 in PSCs and in the interaction of PSCs with pancreatic cancer cells. Human PSCs were isolated using the modified outgrowth method. The effect of inhibiting PAK1 with group 1 PAK inhibitor, FRAX597, on cell proliferation and apoptosis in vitro was measured by thymidine incorporation and annexin V assays, respectively. The effect of depleting host PAK1 on the survival of mice with pancreatic Pan02 cell tumors was evaluated using PAK1 knockout (KO) mice. PAK1 was expressed in isolated PSCs. FRAX597 reduced the activation of PSCs, inhibited PSC proliferation, and increased PSC apoptosis at least in partial by inhibiting PAK1 activity. The decreased expression and activity of PAK1 in PAK1 KO mice tumors was associated with an increased mouse survival. These results implicate PAK1 as a regulator of PSC activation, proliferation and apoptosis. Targeting stromal PAK1 could increase therapeutic response and survival of patients with pancreatic cancer.

The Rey Figure Copy as a Screening Instrument for Perceptual Deficits after Stroke

The aim of the study was to investigate the use of the Rey figure for screening patients for perceptual impairment following stroke. Stroke patients in a trial of a stroke unit were assessed using the Rey figure copy at entry to the study. Those admitted to the stroke unit were also assessed on the Rivermead Perceptual Assessment Battery (RPAB). In 61 patients assessed consecutively on both tests, using conventional clinical cut-off points the Rey figure copy was impaired in 31 out of 32 patients who were impaired on the RPAB. Fifteen patients who failed the Rey figure did not have perceptual problems on the RPAB, indicating that deficits on the Rey figure are not only due to perceptual problems. A receiver operating characteristic curve was plotted to compare different cut-off points. The Rey figure may be used as a brief screening assessment for perceptual deficits following stroke.

Muscle immobilization activates mitophagy and disrupts mitochondrial dynamics in mice

AIM

Skeletal muscle atrophy following prolonged immobilization (IM) is a catabolic state characterized by increased proteolysis and functional deterioration. Previous research indicates that discord of mitochondrial homoeostasis plays a critical role in muscle atrophy. We hypothesized that muscle IM would activate the ubiquitin-proteolysis, autophagy-lysosome (mitophagy) pathway, mitochondrial dynamics remodelling and apoptosis partially controlled by the FoxO signalling pathway.

METHODS

Female FVB/N mice were randomly divided into five groups (n = 8 each): control (CON), IM with banding of one of the hindlimbs for 1, 2 and 3 weeks (1w-, 2w- and 3w-IM) and 2w-IM followed by 1 week of remobilization (RM).

RESULTS

Mitochondrial density and DNA copies in tibialis anterior (TA) muscle were reduced by approx. 80% (P < 0.05 for 2w-IM; P < 0.01 for 3w-IM), along with activation of FoxO3a, atrogin-1 and MuRF1 following 2w- and 3w-IM (P < 0.01). Protein markers of autophagy/mitophagy, such as beclin 1 (approx. 2.7-fold; P < 0.01), LC3, ubiquitin-binding adaptor (approx. 1.47-fold; P < 0.01), Rheb (approx. 1.9-fold; P < 0.05) and parkin (approx. 70%; P < 0.05), were all increased by IM and remained activated after RM, whereas BNIP3 and PINK1 levels were decreased by IM (P < 0.05), but elevated upon RM (P < 0.01). IM decreased Mfn2 expression (approx. 50%; P < 0.01) and increased Fis-1 expression (approx. 2.4-fold; P < 0.05). Muscle apoptosis indicator Bax/Bcl2 ratio was elevated at 2w- to 3w-IM (approx. 3.7-fold; P < 0.01), whereas caspase-3 activity was five- to sixfold higher (P < 0.01) and remained threefold higher above CON (P < 0.05).

CONCLUSION

Our data indicate that IM-induced mitochondrial deterioration is associated with altered protein expressions in the autophagic/mitophagic pathway, more fragmented mitochondrial network and activation of apoptosis partly under the influence of FoxO3 activation.

Perovskite BiFeO3 thin film photocathode performance with visible light activity

Perovskite materials are now an important class of materials in the application areas of photovoltaics and photocatalysis. Inorganic perovskites such as BiFeO3 (BFO) are promising photocatalyst materials with visible light activity and inherent stability. Here we report the large area sol-gel synthesis of BFO films for solar stimulated water photo oxidation. By modifying the sol-gel synthesis process we have produced a perovskite material that has p-type behaviour and a flat band potential of ∼1.15 V (versus NHE). The photocathode produces a density of -0.004 mA cm(-2) at 0 V versus NHE under AM1.5 G illumination. We further show that 0.6 μmol h(-1) of O2 was produced at an external bias of -0.5 V versus Ag/AgCl. The addition of a non-percolating conducting network of Ag increases the photocurrent to -0.07 mA cm(-2) at 0 V versus NHE (at 2% Ag loading) with an increase to 2.7 μmol h(-1) for O2 production. We attribute the enhancement in photoelectrochemical performance to increased light absorption due light scattering by the incorporated Ag particles, improved charge transfer kinetics at the Ag/BFO interface and reduced over potential losses. We support these claims by an observed shift in flat band and onset potentials after Ag modification through UV-vis spectroscopy, Mott-Schottky plots and j-v curve analysis.

Barthel ADL Index: a comparison of administration methods

The Barthel ADL Index is routinely used to assess elderly patients after discharge from hospital. Its inter-rater reliability and criterion validity have been well established. However, the inter-method reliability in administering this scale has not been sufficiently documentated. This study compares post, telephone and interview (visit) methods of administration to investigate their agreement. The index was administered by the three methods in random order after patients were discharged from acute geriatric wards. Results suggest that these three methods are reliable and agree well with each other in the total scores obtained. Analyses of individual item scores indicate poor agreement on one item (stairs). Suggestions on improving the guidelines for this item are outlined.

Glaucarubinone Combined with Gemcitabine Improves Pancreatic Cancer Survival in an Immunocompetent Orthotopic Murine Model

BACKGROUND

Pancreatic cancer continues to have a poor survival rate with an urgent need for improved treatments. Glaucarubinone, a natural product first isolated from the seeds of the tree Simarouba glauca, has recently been recognized as having anti-cancer properties that may be particularly applicable to pancreatic cancer.

METHODS

The effect of glaucarubinone on the growth and migration of murine pancreatic cancer cells was assessed by ³H-thymidine incorporation assay. The survival impact of glaucarubinone alone and in combination with gemcitabine chemotherapy was assessed using an immunocompetent orthotopic murine model of pancreatic cancer.

RESULTS

Glaucarubinone inhibited the growth of the murine pancreatic cancer cell lines LM-P and PAN02. Treatment with either glaucarubinone or gemcitabine reduced proliferation in vitro and the combination was synergistic. The combination treatment improved survival two-fold compared to gemcitabine treatment alone (p = 0.046) in PAN02 cells.

CONCLUSIONS

The synergistic inhibition by glaucarubinone and gemcitabine observed in vitro and the improved survival in vivo suggest that glaucarubinone may be a useful adjunct to current chemotherapy regimens.

FRAX597, a PAK1 inhibitor, synergistically reduces pancreatic cancer growth when combined with gemcitabine

BACKGROUND

Pancreatic ductal adenocarcinoma remains one of the most lethal of all solid tumours. Treatment options are limited and gemcitabine-based chemotherapy remains the standard of care. Although growing evidence shows that p21-activated kinase 1 (PAK1) plays a crucial role in pancreatic cancer, its role has not been fully elucidated. This study aimed to characterise the expression and functional relevance of PAK1 in pancreatic cancer.

METHODS

PAK1 expression was measured in pancreatic cancer specimens by immunohistochemistry and in pancreatic cancer cell lines by western blotting. The effect of inhibition of PAK1 by either shRNA knock-down (KD), or by a selective inhibitor, FRAX597, alone or in combination with gemcitabine, on cell proliferation and migration/invasion was measured by thymidine uptake and Boyden chamber assays, respectively. The effect on tumour growth and survival was assessed in orthotopic murine models.

RESULTS

PAK1 was expressed in all human pancreatic cancer samples tested, an7d was upregulated in all pancreatic cancer cell lines tested. PAK1 KD inhibited pancreatic cancer cell growth and survival, and increased sensitivity to gemcitabine treatment. AKT activity and HIF1α expression were also inhibited. FRAX597 inhibited pancreatic cancer cell proliferation, survival, and migration/invasion. When combined with gemcitabine, FRAX597 synergistically inhibited pancreatic cancer proliferation in vitro and inhibited tumour growth in vivo.

CONCLUSIONS

These results implicate PAK1 as a regulator of pancreatic cancer cell growth and survival. Combination of a PAK1 inhibitor such as FRAX597 with cytotoxic chemotherapy deserves further study as a novel therapeutic approach to pancreatic cancer treatment.

Clinical associations of anosognosia in mild cognitive impairment and Alzheimer's disease

AIMS AND OBJECTIVE

While loss of insight of cognitive deficits is a common phenomenon in patients with Alzheimer's disease (AD), there is a lack of consensus regarding the presence of impaired insight among patients with mild cognitive impairment (MCI). We aim to investigate the clinical, cognitive, and behavioral associations of anosognosia in AD and MCI subjects.

METHODS

A consecutive series of 87 subjects (30 healthy older patients, 21 MCI, and 36 AD) each accompanied by a caregiver, underwent clinical assessment including the evaluation of insight using the Anosognosia Questionnaire for Dementia (AQD). We also separately assessed Intellectual Function (AQD-IF) and Behavior domains of the AQD scale. Regression models were subsequently used to investigate associations of AQD scores with cognitive and other neuropsychiatric symptoms, including depression and apathy.

RESULTS

Both AD and MCI groups demonstrated significant anosognosia compared with the healthy control group. In the AD group, 55.6% had "Mild Anosognosia," and 27.8% had "Severe Anosognosia." In the MCI group, 42.9% showed "Mild Anosognosia," and 9.5% had "Severe Anosognosia." Greater levels of AQD-Total and AQD-IF were associated with lower Mini-mental state examination and higher apathy scores in the AD group. In the MCI group, caregiver burden was significantly associated with AQD-Total (p = 0.016) and AQD-IF (p = 0.039).

CONCLUSION

The results indicated that anosognosia is common in both AD and MCI patients and associated with cognitive dysfunction and apathy in AD. The findings of this study warrant further research to delineate the mechanisms of anosognosia as it poses a challenge to treatment outcomes.

Glaucarubinone and gemcitabine synergistically reduce pancreatic cancer growth via down-regulation of P21-activated kinases

Pancreatic cancer is one of the most lethal of human malignancies. Nearly 100% cases of pancreatic cancer carry mutations in KRas. P-21-activated kinases (PAKs) are activated by and act downstream of KRas. Glaucarubinone, a natural product first isolated from the seeds of the tree Simarouba glauca, was originally developed as an antimalarial drug, and has more recently been recognised as an anticancer agent. The aims of this study were to determine whether glaucarubinone, alone or in combination with the front-line chemotherapeutic agent gemcitabine, would inhibit the growth of pancreatic cancer cells in vitro or in vivo and the mechanism involved. Growth of the human pancreatic cancer cell lines PANC-1 and MiaPaCa-2 was measured by (3)H-thymidine incorporation in vitro, and by volume as xenografts in SCID mice. The expression and activities of the two serine/threonine kinases PAK1 and PAK4, which are key regulators of cancer progression, were measured by Western blotting. Here we report that glaucarubinone decreased proliferation and migration of pancreatic cancer cells in vitro, and reduced their growth as xenografts in vivo. Treatment with glaucarubinone and gemcitabine reduced proliferation in vitro and tumor growth in vivo more than treatment with either glaucarubinone or gemcitabine alone. Treatment with glaucarubinone reduced PAK1 and PAK4 activities, which were further decreased by the combination of glaucarubinone and gemcitabine. These results indicate that glaucarubinone reduced pancreatic cancer cell growth at least in part via inhibition of pathways involving PAK1 and PAK4. The synergistic inhibition by glaucarubinone and gemcitabine observed both in vitro and in vivo suggests that glaucarubinone may be a useful adjunct to current regimes of chemotherapy.

Comparison of two syngeneic orthotopic murine models of pancreatic adenocarcinoma

BACKGROUND

Pancreatic adenocarcinoma has an extremely poor prognosis. The use of appropriate in vivo models is essential in devising methods to improve treatment outcomes.

METHODS

A pancreatic adenocarcinoma model based on tumor injection into the pancreatic head was compared with a pancreatic tail injection model in C57/BL6 mice. The murine pancreatic adenocarcinoma cell line PAN02, dispersed in Matrigel™, was used for tumor induction.

RESULTS

Tumors developed in all animals in both models. Tumor size was more consistent within the pancreatic tail group at 20 days following induction, with no evidence of metastatic disease. Animals in the pancreatic head injection group showed signs of reduced health by 20 days following injection and developed jaundice. Microscopic liver metastases were noted in some of these animals at this time point. The overall survival of animals at 40 days following tumor induction was significantly lower in the pancreatic head injection group (0% vs. 35%; p < .001). Multiple liver metastases were noted in five of 10 (50%) animals in the head injection group, without evidence of peritoneal metastases. In the pancreatic tail injection group, 18 of 20 (90%) animals had multiple peritoneal metastases, and nine of 20 (45%) animals had evidence of isolated liver deposits. Tumors in both regions of the pancreas had similar histologic characteristics, with a dense fibrotic stroma at the interface between the tumor and the normal pancreas.

CONCLUSION

Pancreatic head and tail orthotopic cancer models produce consistent tumors, but the patterns of tumor spread and survival differ according to the site of injection.

Diagnostic performance of the Chinese Frontal Assessment Battery in early cognitive impairment in an Asian population

BACKGROUND

The Frontal Assessment Battery (FAB) has been shown to be useful in evaluating frontal dysfunction. There is a paucity of studies validating cutoffs in the early cognitive impairment. We aim to validate the Chinese FAB in Asian subjects with mild cognitive impairment (MCI) and early dementia.

METHODS

Eighty subjects with MCI and mild dementia and 100 cognitively healthy community subjects were studied. ROC analysis was done to determine the Chinese FAB's optimal cutoff scores for age- and education-adjusted subgroups.

RESULTS

Chinese FAB scores were significantly lower in early cognitive impairment compared with cognitively normal controls. The optimal cutoff score was 12/13 (sensitivity 92%, specificity 78.7%). A similar cutoff score was obtained following age-adjustment and for subjects with <6 years' education. Of note, the optimal cutoff for subjects with ≥6 years' education was 13/14 (sensitivity 91.8%, specificity 70.3%), an improved diagnostic performance compared to the earlier reported 11/12 cutoff. In comparison, the Mini-Mental Status Examination (MMSE) had lower rule-out accuracy (77% sensitivity, 91.2% specificity). The combination of the Chinese FAB and MMSE was superior to either test in isolation.

CONCLUSION

The education-adjusted Chinese FAB has good diagnostic performance, which can supplement the MMSE in early cognitive impairment evaluation with construct differences observed between the Chinese FAB and MMSE.

Cognitive screening in Asia: recognizing the role of the patient-family unit

BACKGROUND/AIMS

Cognitive screening programmes may improve awareness and help at-risk subjects receive earlier medical attention. Cognitive profiles of subjects who attend cognitive screening by personal choice (self-referred) compared to those where the referral was initiated by family members (family-referred) were compared.

METHODS

A cross-sectional survey of community subjects attending a cognitive screening initiative. Performance on the MMSE, Frontal Assessment Battery (FAB), Elderly Cognitive Assessment Questionnaire (ECAQ) and Even Briefer Assessment Scale for Depression was evaluated.

RESULTS

A total of 342 subjects with a mean age of 59.2 +/- 9.0 years were screened. Overrepresentation of Chinese and Indian subjects and underrepresentation of Malay subjects was noted. The prevalence of cognitive impairment ranged from 7.0 to 9.6% depending on the screening instrument used. Of the 342 subjects, 267 were self-referred, while 75 subjects were family-referred. Family-referred subjects had lower MMSE (p < 0.001), lower ECAQ (p < 0.001) and lower FAB (p < 0.001) scores but were not more depressed compared to self-referred subjects (p = 0.904). Only the difference in ECAQ scores remained significant after adjustment for baseline differences in age and education. The prevalence of hypertension, diabetes mellitus and hypercholesterolaemia was not statistically different between the 2 groups.

CONCLUSIONS

Family members play a crucial role in the diagnosis of cognitive impairment, especially in older subjects with fewer years of education.

Measures of health-related quality of life and functional status in survivors of oral cavity cancer who have had defects reconstructed with radial forearm free flaps

The aim of this study was to evaluate (by postal questionnaire) quality of life and function in patients who have had resections of oral cancer and reconstruction by radial forearm flaps. Between October 1987 and December 2002, 258 patients had reconstructions by radial forearm flaps after resection of tumours in the oral cavity. Of these, 139 surviving patients were identified from the database and were sent questionnaires comprising five sections: Functional Assessment of Cancer Therapy-General (FACT-G) and -Head and Neck (FACT-HN); University of Washington Quality of Life Scale (UWQoL); Performance Status Scale for Head and Neck Cancer (PSS-HN); and the final section addressed dental rehabilitation and morbidity at the donor site. Sixty-three questionnaires (45%) were returned. In 17 (27%), parts of the questionnaire were incomplete. The median UWQoL score was 623/900, FACT-G was 92/108, FACT-HN was 31/48, and PSS-HN showed that eating in public, understandability of speech and normality of diet were 75/100, 75/100 and 50/100, respectively. The effect of stage and site on quality of life and function did not reach statistical significance. The effect of radiotherapy on speech (p=0.036) and diet (p=0.007) was significant. Patients who worried about their cancer returning had a lower UWQoL score (p=0.016). Ninety percent regarded their arm as disfigured, but 81% felt comfortable wearing short-sleeved shirts. Sensation and function of the hand were reported as normal in 87 and 92%, respectively. We conclude that patients who have had oral cancer have a persistent reduction in quality of life and function long after completion of treatment. The effects can be assessed by postal questionnaire, but the low rate of return (45%) and difficulties with completion reduce the quality of the data. Quality of life and function are essential components of improvements in outcome.

Does the density of lymphatic vascular space invasion affect the prognosis of stage Ib and IIA node negative carcinoma of the cervix?

Lymphatic vascular space invasion (LVSI) has been noted as a poor prognostic factor in many tumors. In some studies of carcinoma of the cervix, LVSI has been demonstrated to be independent of other prognostic factors. The aim of this study is to evaluate if, by a simple quantitative technique, the density of lymphatic invasion could be correlated with the risk of recurrence in node negative early stage carcinoma of the cervix. We analyzed the pathology and clinical course of 71 consecutive patients with stage IB and IIA carcinoma of the cervix treated primarily by radical hysterectomy and pelvic lymphadenectomy. All cases had negative nodes and adequate surgical margins. There were 67 patients suitable for evaluation. Tumour type, grade, stage and the dimensions of the tumor were recorded. The density of LVSI was categorized as absent (45%), mild (15%), moderate (33%) or severe (7%) depending on the number of lymphatic vascular spaces involved per high power field in the worst affected slide. The patients were followed for 2-8(1/2) years with a mean follow up of 4 years and 2 months. There were 13 recurrences and 7 deaths. All recurrences occurred in less than 2 years after surgery. The risk of recurrence was 40% for patients with extensive LVSI, 32% for moderate, 30% for mild and 3% if LVSI was absent. Only the presence of LVSI was associated with an increased risk of recurrence. The density of lymphatic invasion as represented by the number of lymphatic spaces occupied on the worst histological slide offered no further clinically useful information.

Partial characterization of a 17 kDa acidic protein, EFP, induced by thiocarbamate in the early flowering phase in Asparagus seedlings

Asparagus officinalis seedlings treated with either thiocarbamates or carbamates are induced to flower within 2-3 weeks of application. SDS-PAGE and 2-D PAGE resolutions of total soluble proteins of treated seedlings showed the accumulation of an acidic 17 kDa polypeptide. Partial amino acid sequence of the acidic protein showed homology to the wound-responsive A. officinalis PR 1, AoPR1. We named this protein EFP, early flowering protein, owing to its advanced appearance during the early transition from vegetative to floral phase. Carbamates and thiocarbamates that induced more than 80% flowering rates corresponded with increased level of EFP while compounds that are weak flower inducers showed reduced amount of EFP. The observation thus defined the correlationship of EFP to variable flowering rates.

SORT: a validation study with stroke patients. Salford Objective Recognition Test

The Salford Objective Recognition Test (SORT) was developed as a measure of recognition memory suitable for use with elderly people as it requires a shorter administration time than Warrington's Recognition Memory Test. Normative data for the SORT were collected from 50 normal elderly people living in the community. Fifty stroke patients were assessed on the SORT and other tests of psychological functioning. The words and faces subtests were found to correlate well with other measures of memory. The SORT was found to be uninfluenced by the effects of sex and time since onset of stroke, but was affected by language difficulties and perception problems. The split-half reliability of the test was found to be good as alternative versions of the subtests correlated well with each other.