Precision-activated T-cell engagers targeting HER2 or EGFR and CD3 mitigate on-target, off-tumor toxicity for immunotherapy in solid tumors.

To enhance the therapeutic index of T-cell engagers (TCEs), we engineered masked, precision-activated TCEs (XPAT proteins), targeting a tumor antigen (human epidermal growth factor receptor 2 (HER2) or epidermal growth factor receptor (EGFR)) and CD3. Unstructured XTEN polypeptide masks flank the N and C termini of the TCE and are designed to be released by proteases in the tumor microenvironment. In vitro, unmasked HER2-XPAT (uTCE) demonstrates potent cytotoxicity, with XTEN polypeptide masking providing up to 4-log-fold protection. In vivo, HER2-XPAT protein induces protease-dependent antitumor activity and is proteolytically stable in healthy tissues. In non-human primates, HER2-XPAT protein demonstrates a strong safety margin (>400-fold increase in tolerated maximum concentration versus uTCE). HER2-XPAT protein cleavage is low and similar in plasma samples from healthy and diseased humans and non-human primates, supporting translatability of stability to patients. EGFR-XPAT protein confirmed the utility of XPAT technology for tumor targets more widely expressed in healthy tissues.

Guidance on the management of familial hypercholesterolaemia in Hong Kong: an expert panel consensus viewpoin.

In 2016, meetings of groups of physicians and paediatricians with a special interest in lipid disorders and familial hypercholesterolaemia were held to discuss several domains of management of familial hypercholesterolaemia in adults and children in Hong Kong. After reviewing the evidence and guidelines for the diagnosis, screening, and management of familial hypercholesterolaemia, consensus was reached on the following aspects: clinical features, diagnostic criteria, screening in adults, screening in children, management in relation to target plasma low-density lipoprotein cholesterol levels, detection of atherosclerosis, lifestyle and behaviour modification, and pharmacotherapy.

Rab35-dependent extracellular nanovesicles are required for induction of tumour supporting stroma.

Communication between diseased cells and the microenvironment is a complex yet crucial element in progression of varied pathological processes. Recent studies in cancer highlight an important role for small extracellular nanovesicles secreted by cancer cells as modulators of cancer-associated stroma, leading to enhanced angiogenesis and metastatic priming. The intrinsic factors regulating extracellular nanovesicle biogenesis and secretion are therefore relevant in studies of nano-communication in the cancer milieu. We generated prostate cancer cells bearing stable knockdown of several candidate vesicle regulating factors and examined the impact on cell health, vesicle secretion and on communication with fibroblastic stromal cells. We highlight that RAB11B and RAB35 regulate phenotypically distinct nanovesicle populations, each accounting for only around 20% of the total. Depleting RAB35, but not RAB11B leaves a remaining population of vesicles whose phenotype is insufficient for driving fibroblast to myofibroblast differentiation, leading to attenuated motile behaviours in 3D in vitro models. Co-implantation of tumour cells with stromal fibroblasts in xenografts similarly showed that RAB11B knockdown had little effect on growth rates in vivo. In contrast, significant attenuation in growth, and attenuation of myofibroblasts at the tumour site was evident when using RAB35-knockdown cells. The study concludes that a RAB35 regulated nanovesicle sub-population is particularly important for communication between cancer and stromal cells, and is required for generating a tumour-supportive microenvironment.

RSPO3 antagonism inhibits growth and tumorigenicity in colorectal tumors harboring common Wnt pathway mutations.

Activating mutations in the Wnt pathway are a characteristic feature of colorectal cancer (CRC). The R-spondin (RSPO) family is a group of secreted proteins that enhance Wnt signaling and RSPO2 and RSPO3 gene fusions have been reported in CRC. We have previously shown that Wnt pathway blockers exhibit potent combinatorial activity with taxanes to inhibit tumor growth. Here we show that RSPO3 antagonism synergizes with paclitaxel based chemotherapies in patient-derived xenograft models (PDX) with RSPO3 fusions and in tumors with common CRC mutations such as APC, ß-catenin, or RNF43. In these latter types of tumors that represent over 90% of CRC, RSPO3 is produced by stromal cells in the tumor microenvironment and the activating mutations appear to sensitize the tumors to Wnt-Rspo synergy. The combination of RSPO3 inhibition and taxane treatment provides an approach to effectively target oncogenic WNT signaling in a significant number of patients with colorectal and other intestinal cancers.

WNT antagonists exhibit unique combinatorial antitumor activity with taxanes by potentiating mitotic cell death.

The WNT pathway mediates intercellular signaling that regulates cell fate in both normal development and cancer. It is widely appreciated that the WNT pathway is frequently dysregulated in human cancers through a variety of genetic and epigenetic mechanisms. Targets in the WNT pathway are being extensively pursued for the development of new anticancer therapies, and we have advanced two WNT antagonists for clinical development: vantictumab (anti-FZD) and ipafricept (FZD8-Fc). We examined the antitumor efficacy of these WNT antagonists in combination with various chemotherapies in a large set of patient-derived xenograft models. In responsive models, WNT blockade led to profound synergy with taxanes such as paclitaxel, and the combination activity with taxanes was consistently more effective than with other classes of chemotherapy. Taxane monotherapy increased the frequency of cells with active WNT signaling. This selection of WNT-active chemotherapy-resistant tumorigenic cells was prevented by WNT-antagonizing biologics and required sequential dosing of the WNT antagonist followed by the taxane. The WNT antagonists potentiated paclitaxel-mediated mitotic blockade and promoted widespread mitotic cell death. By blocking WNT/ß-catenin signaling before mitotic blockade by paclitaxel, we found that this treatment effectively sensitizes cancer stem cells to taxanes. This combination strategy and treatment regimen has been incorporated into ongoing clinical testing for vantictumab and ipafricept.

Four pairs of gene-gene interactions associated with increased risk for type 2 diabetes (CDKN2BAS-KCNJ11), obesity (SLC2A9-IGF2BP2, FTO-APOA5), and hypertension (MC4R-IGF2BP2) in Chinese women.

Metabolic disorders including type 2 diabetes, obesity and hypertension have growing prevalence globally every year. Genome-wide association studies have successfully identified many genetic markers associated to these diseases, but few studied their interaction effects. In this study, twenty candidate SNPs from sixteen genes are selected, and a lasso-multiple regression approach is implemented to consider the SNP-SNP interactions among them in an Asian population. It is found out that the main effects of the markers are weak but the interactions among the candidates showed a significant association to diseases. SNPs from genes CDKN2BAS and KCNJ11 are significantly associated to risk for developing diabetes, and SNPs from FTO and APOA5 might interact to play an important role for the onset of hypertension.

Anti-DLL4 has broad spectrum activity in pancreatic cancer dependent on targeting DLL4-Notch signaling in both tumor and vasculature cells.

PURPOSE: We previously showed that targeting Delta-like ligand 4 (DLL4) in colon and breast tumors inhibited tumor growth and reduced tumor initiating cell frequency. In this report, we have extended these studies to pancreatic cancer and probed the mechanism of action in tumor and stromal cells involved in antitumor efficacy. EXPERIMENTAL DESIGN: Patient-derived pancreatic xenograft tumor models were used to evaluate the antitumor effect of anti-DLL4. To investigate the mechanism of action, we compared the activity of targeting DLL4 in tumor cells with an anti-human DLL4 antibody (anti-hDLL4) and in the host stroma/vasculature with an anti-mouse DLL4 antibody (anti-mDLL4). The effect of these antibodies on cancer stem cell frequency was examined by in vivo limiting dilution assays. RESULTS: The combination of anti-hDLL4 and anti-mDLL4 was efficacious in a broad spectrum of pancreatic tumor xenografts and showed additive antitumor activity together with gemcitabine. Treatment with either anti-hDLL4 or anti-mDLL4 delayed pancreatic tumor recurrence following termination of gemcitabine treatment, and the two together produced an additive effect. Anti-hDLL4 had a pronounced effect in reducing the tumorigenicity of pancreatic cancer cells based on serial transplantation and tumorsphere assays. In contrast, disruption of tumor angiogenesis with anti-mDLL4 alone or with anti-VEGF had minimal effects on tumorigenicity. Gene expression analyses indicated that anti-DLL4 treatment regulated genes that participate in Notch signaling, pancreatic differentiation, and epithelial-to-mesenchymal transition. CONCLUSIONS: Our findings suggest a novel therapeutic approach for pancreatic cancer treatment through antagonism of DLL4/Notch signaling.

The effects of diet and orlistat on body weight and lipid profiles in high risk Chinese patients with coronary artery disease, obesity and hypercholesterolemia.

BACKGROUND: Orlistat is a gastrointestinal lipase inhibitor approved for use in obesity. So far, no evidence has been reported on the use of orlistat in obese patients with coronary artery disease (CAD). AIM: To investigate the effect of orlistat on body weight and lipid profiles in obese patients with CAD and hypercholesterolemia. METHODS: Thirty non-diabetic patients with CAD, body mass index (BMI) > or = 25 kg/m(2) and low-density lipoprotein cholesterol (LDL-C) > or = 2.6 and < 4.1 mmol/L were put on diet for 12 weeks. Those still having a BMI > or = 25 kg/m(2) received orlistat 120 mg thrice daily for another 24 weeks. RESULTS: BMI was significantly reduced by 1.7% after 12 weeks of dietary treatment. The 24-week orlistat treatment resulted in further significant reduction in BMI (-2.8%) and LDL-C (-7.0%). CONCLUSION: Diet and orlistat treatment significantly reduced BMI and improved LDL-C in obese patients with CAD and hypercholesterolemia.

Thoracic actinomycosis in an adolescent mimicking chest wall tumor or pulmonary tuberculosis.

Actinomycosis is a rare disease in children and young adolescents and its thoracic manifestations accounted for a minority of all cases. We report a case of a 12-year-old boy who presented with a right anterior chest wall mass for one week together with weight loss and low grade fever for one month. His symptoms and signs as well as the results of the radiological investigations (i.e. chest X-ray and computed tomography (CT) of thorax with contrast) mimicked pulmonary tuberculosis or chest wall tumor. The definite diagnosis of actinomycosis relies on the Gram stain microscopy and culture of the chest wall lesion aspirates. An early and accurate diagnosis can prevent the patient from unnecessary invasive procedures such as open lung biopsy or thoracotomy. The mainstay of the treatment of actinomycosis remains to be a combination of abscess drainage as well as prolonged antibiotics such as penicillin. Follow-up CT scan of thorax with contrast is useful in monitoring the progress of disease recovery.

Prevalence of asymptomatic intracranial atherosclerosis in high-risk patients.

We used transcranial Doppler to screen 3,057 patients who had at least one vascular risk factor of hypertension, diabetes, or hyperlipidemia and found 385 (12.6%) had middle cerebral artery stenosis. Elderly, hypertension, diabetes, and hyperlipidemia were associated factors. The prevalence escalated quadratically with increasing number of associated factors: from 7.2% for one, to 29.6% for four associated factors. Asymptomatic middle cerebral artery stenosis is common in patients with vascular risk factors.

Association of smoking with increasing vascular involvement in type 2 diabetic Chinese patients.

PURPOSE: To identify the relationship between smoking and the metabolic profile and existing vascular disease in Chinese type 2 diabetic patients. METHODS: 1710 diabetic patients were screened for complications, and biochemical and anthropometric vascular risk factors. As most smokers were male, differences were only compared between male current (n = 196) and never smoking patients (n = 300). RESULTS: The smokers had higher glycosylated haemoglobin levels (8.2 +/- 2.0 vs. 7.6 +/- 1.8%, p < 0.001) than never smokers, despite a greater proportion receiving hypoglycaemic agents (87.5 vs. 79.6%, p = 0.003). Male smokers compared to never smokers had lower HDL-cholesterol levels (1.12 +/- 0.31 vs. 1.20 +/- 0.30 mmol/L, p = 0.006), and elevated albumin-to-creatinine ratio (3.57 [2.68-4.75] vs. 2.47 [1.99-3.05] mg/mmol, p = 0.040). However, diastolic blood pressure was lower in the smoking group (78 +/- 12 vs. 82 +/- 12 mmHg, p = 0.001) even though they received less blood pressure-lowering treatments (23.8 vs. 33.2%, p = 0.034). The prevalence of peripheral vascular disease was increased in the diabetic patients who smoked compared to nonsmokers (7.1 vs. 2.8%, p = 0.039). CONCLUSIONS: Smoking was associated with a more adverse metabolic profile and peripheral vascular disease. As mainland China undergoes rapid modernisation and urbanisation, the observed effects of smoking means tobacco control becomes increasingly important to prevent or minimise potential health impacts and chronic disease.

MicroAlbuminuria Prevalence Study (MAPS) in hypertensive type 2 diabetic patients in Hong Kong.

OBJECTIVES: To assess the prevalence of macroalbuminuria and microalbuminuria, and the level of blood pressure control in patients with type 2 diabetes and hypertension in Hong Kong. DESIGN: Cross-sectional clinic-based epidemiological study. SETTING: Six medical centres (including two public hospital diabetes centres) in Hong Kong. PATIENTS: Recruited from the medical centres from April to November 2002, after excluding those with bacteriuria and haematuria. MAIN OUTCOME MEASURES: Body mass index; blood pressure; levels of blood glucose, macroalbuminuria, and microalbuminuria; treatments for hypertension and diabetes. RESULTS: The as per-protocol recruited population of 437 hypertensive type 2 diabetic patients had a mean age of 61.7 (standard error, 0.5) years. Overall, the prevalence of diabetic nephropathy in this population was high; 18.3% had macroalbuminuria (95% confidence interval, 16.5-20.2%) and 24.9% had microalbuminuria (95% confidence interval, 22.9-27.0%). Predictive factors were advanced age, male sex, poor blood pressure control, and existing cardiovascular complications. Whilst almost all patients (96.1%) were receiving treatment for hypertension, only 25.6% had systolic/diastolic blood pressures below the 130/85 mm Hg target. CONCLUSIONS: In Hong Kong, the prevalence of microalbuminuria and macroalbuminuria is high in type 2 diabetic patients with hypertension, particularly in males and those with poorly controlled systolic blood pressure. Tight glycaemic control, antihypertensive therapy, and use of renin-angiotensin system inhibitors/blockers are necessary to retard the progression of nephropathy to advanced renal disease.

Supply problems of unlicensed and off-label medicines after discharge.

A total of 709 unlicensed and off-label medicines were prescribed for 338 patients discharged from a paediatric hospital between 1 November 2003 and 31 January 2004. Thirty three per cent of patients had difficulty obtaining these medications in primary care which caused treatment disruption. The main problems were: (1) community pharmacies being unable to supply; and (2) GPs' refusal to prescribe.

Metabolic syndrome by the international diabetes federation definition in Hong Kong Chinese.

In this report, we aimed to examine the impact of the new International Diabetes Federation (IDF) definition on the prevalence and clinical characteristics of subjects with metabolic syndrome (MES). Data were obtained from a prevalence survey for cardiovascular risk factors in a Hong Kong Chinese working population. There were 1513 subjects well representing all occupational groups from managers to general laborers [910 (60.1%) men and 603 (39.9%) women (mean age 37.5+/-9.2, median 37.0, range 18-66 years)]. The crude prevalence of MES defined by the IDF criterion was 7.4% (compared to other criteria: NCEP, 9.6%; WHO, 13.4% and EGIR, 8.9%). The age-standardized prevalence of MES by the IDF criterion was 8.8% in women and 7.3% in men. Subjects with MES defined by IDF criterion had higher body mass index and waist compared to those with MES defined by NCEP or WHO criteria, and lower triglyceride compared to those with MES defined by NCEP criterion after adjustment for age, gender and smoking. Non-MES subjects defined by IDF criterion had higher 2h glucose and insulin resistance compared to non-MES subjects defined by WHO. In conclusion, the new IDF criterion for MES is easy to implement in clinical practice. It may be potentially more 'specific' in identifying subjects with MES although compared to the NCEP criterion, it may have missed a proportion of subjects, especially men, who have metabolic derangement. Prospective and interventional studies are needed to validate the prognostic values of this new definition in comparison with other existing definitions.

Prediction of cardiovascular and total mortality in Chinese type 2 diabetic patients by the WHO definition for the metabolic syndrome.

AIM: The aim of this study is to investigate the prevalence of metabolic syndrome (MES) in type 2 diabetic patients and the predictive values of the World Health Organization (WHO) and National Cholesterol Education Programme (NCEP) definitions and the individual components of the MES on total and cardiovascular mortality. METHODS: A prospective analysis of a consecutive cohort of 5202 Chinese type 2 diabetic patients recruited between July 1994 and April 2001. RESULTS: The prevalence of the MES was 49.2-58.1% depending on the use of various criteria. There were 189 deaths (men: 100 and women: 89) in these 5205 patients during a median (interquartile range) follow-up period of 2.1 (0.3-3.6 years). Of these, 164 (87%) were classified as cardiovascular deaths. Using the NCEP criterion, patients with MES had a death rate similar to those without (3.51 vs. 3.85%). By contrast, based on the WHO criteria, patients with MES had a higher mortality rate than those without (4.3 vs. 2.4%, p = 0.002). Compared to patients with neither NCEP- nor WHO-defined MES, only the group with MES defined by the WHO, but not NCEP, criterion had significantly higher mortality rate (2.6 vs. 6.8%, p < 0.001). Using Cox regression analysis, only age, duration of diabetes and smoking were identified as independent factors for cardiovascular or total death. Among the various components of MES, hypertension, low BMI and albuminuria were the key predictors for these adverse events. CONCLUSIONS: In Chinese type 2 diabetic patients, the WHO criterion has a better discriminative power over the NCEP criterion for predicting death. Among the various components of the MES defined either by WHO or NCEP, hypertension, albuminuria and low BMI were the main predictors of cardiovascular and total mortality.

A beta-lactamase with reduced immunogenicity for the targeted delivery of chemotherapeutics using antibody-directed enzyme prodrug therapy.

Antibody-directed enzyme prodrug therapy (ADEPT) delivers chemotherapeutic agents in high concentration to tumor tissue while minimizing systemic drug exposure. beta-Lactamases are particularly useful enzymes for ADEPT systems due to their unique substrate specificity that allows the activation of a variety of lactam-based prodrugs with minimal interference from mammalian enzymes. We evaluated the amino acid sequence of beta-lactamase from Enterobacter cloacae for the presence of human T-cell epitopes using a cell-based proliferation assay using samples from 65 community donors. We observed a low background response that is consistent with a lack of preexposure to this enzyme. beta-Lactamase was found to contain four CD4+ T-cell epitopes. For two of these epitopes, we identified single amino acid changes that result in significantly reduced proliferative responses while retaining stability and activity of the enzyme. The beta-lactamase variant containing both changes induces significantly less proliferation in human and mouse cell assays, and 5-fold lower levels of IgG1 in mice were observed after repeat administration of beta-lactamase variant with adjuvant. The beta-lactamase variant should be very suitable for the construction of ADEPT fusion proteins, as it combines high activity toward lactam prodrugs, high plasma stability, a monomeric architecture, and a relatively low risk of eliciting an immune response in patients.

Inter-relationships between DNA damage, ascorbic acid and glycaemic control in Type 2 diabetes mellitus.

AIMS: The onset of complications in Type 2 diabetes mellitus (DM) patients cannot be predicted in individuals. Evidence suggests a link between complications and hyperglycaemia, oxidative stress and antioxidants, but causality is unclear. This study investigated baseline (entry) fasting plasma ascorbic acid, lymphocytic DNA damage and glycaemic control in Type 2 DM as part of a long-term study, the aim of which is to explore a biomarker profiling approach to identify and improve outcome in high-risk subjects. METHODS: A cross-sectional study, in which DNA damage, glycated haemoglobin (HbA(1c)), fasting plasma glucose (FPG) and ascorbic acid (AA) were measured on fasting blood samples collected from 427 Type 2 DM subjects. RESULTS: DNA damage was significantly (P < 0.0001) and directly correlated to both FPG (r = 0.540) and HbA(1c) (r = 0.282), and was significantly (P < 0.0001), independently and inversely correlated to plasma AA (r = -0.449). In those subjects with both poor glycaemic control and low AA (< 48 microm, the overall mean value for the study group), DNA damage was significantly (P < 0.005) higher compared with those subjects with a similar degree of hyperglycaemia but with AA above the mean. CONCLUSIONS: The novel finding of a significant inverse relationship between plasma AA and DNA damage in Type 2 DM indicates that poorly controlled diabetic subjects might benefit from increased dietary vitamin C. The data also have important implications for biomarker profiling to identify those subjects who might benefit most from intensive therapy. Longer-term follow-up is underway.