Abstract 129: Tumor-associated macrophages secrete CCL2 and induce the invasive phenotype of human breast epithelial cells through upregulation of ERO1-alpha and MMP-9

Tumor-associated macrophages (TAMs) are major components of tumor microenvironment that promote invasion and metastasis of cancer cells. In this study, we investigated the effect of TAMs on phenotypic conversion of non-neoplastic MCF10A human breast epithelial cells using an indirect co-culture system. Co-culture with TAMs induced epithelial-to-mesenchymal transition, invasive phenotype, and MMP-9 upregulation in MCF10A cells. Comparative proteomic analysis revealed that endoplasmic reticulum oxidoreductase (ERO)1-alpha was increased in MCF10A cells co-cultured with TAMs compared to that in mono-cultured cells. ERO1-alpha was crucial for TAMs-induced invasive phenotype and MMP-9 upregulation involving transcription factors c-fos and c-Jun. Cytokine array analysis showed that levels of interleukin (IL)-6, C-X-C motif ligand (CXCL)1, C-C motif ligand (CCL)2, growth-regulated protein (GRO), IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF) were increased in conditioned media of co-cultured cells. Among these cytokines increased in conditioned media of co-cultured cells, CCL2 was secreted from TAMs, leading to induction of ERO1-alpha, MMP-9 upregulation, and invasiveness in MCF10A cells. Our findings elucidated a molecular mechanism underlying the aggressive phenotypic change of non-neoplastic breast cells by co-culture with TAMs, providing useful information for prevention or treatment of recurrent breast cancer

Note: This abstract was not presented at the meeting.

Citation Format: Seungeun Lee, Eunhye Lee, EunYi Ko, Mina Ham, Hye Min Lee, Eun-Sook Kim, Minsoo Koh, Hyun Kyung Lim, Joohee Jung, So Yeon Park, Aree Moon. Tumor-associated macrophages secrete CCL2 and induce the invasive phenotype of human breast epithelial cells through upregulation of ERO1-alpha and MMP-9 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 129.

Atypicalities of Gesture Form and Function in Autistic Adults

While well-represented on clinical measures, co-speech gesture production has never been formally studied in autistic adults. Twenty-one verbally fluent autistic adults and 21 typically developing controls engaged in a controlled conversational task. Group differences were observed in both semantic/pragmatic and motoric features of spontaneously produced co-speech gestures. Autistic adults prioritized different functions of co-speech gesture. Specifically, they used gesture more than controls to facilitate conversational turn-taking, demonstrating a novel nonverbal strategy for regulating conversational dynamics. Autistic adults were more likely to gesture unilaterally than bilaterally, a motoric feature of gesture that was individually associated with autism symptoms. Co-speech gestures may provide a link between nonverbal communication symptoms and known differences in motor performance in autism.

Abstract OT2-04-02: A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress

Background

In patients with early stage breast cancer, regional nodal irradiation (RNI) is added to whole breast irradiation (WBI) in order to control microscopic regional disease and to prevent systemic spread of cancer. According to recent randomized trials (MA.20 and EORTC 22922-10925), prophylactic RNI was associated with improvement in disease-free survival (DFS) in the patients with high-risk node negative or pN1 breast cancer. However, systemic agents now known to improve loco-regional control, such as taxane or endocrine therapy, were prescribed to a small percentage of patients in the studies. The benefit of RNI found in the previous studies might be attributed to incorporation of less effective systemic treatments. The impact of prophylactic RNI in pN1 breast cancer should be evaluated in the patients receiving modern systemic treatment. The current study was conducted to compare the effect of post-lumpectomy WBI vs WBI plus RNI on DFS in pN1 breast cancer patients who received adjuvant taxane-based chemotherapy.

Methods

This study is a multicenter, phase 3, randomized controlled non-inferiority trial (NCT03269981). Eligibility criteria are ≥ 20 years female; pathologically proven invasive carcinoma of the breast; one to three positive axillary lymph nodes (pN1) in pathologic specimen; receiving breast-conserving surgery followed by taxane-based chemotherapy; having adjuvant endocrine therapy or anti-HER2 treatment according to molecular subtype of tumor. Patients are randomly assigned in a 1:1 ratio to receive WBI or WBI plus RNI. Patient randomization was stratified by molecular subtype of tumor (i.e. luminal A/luminal B/luminal HER2/HER2-enriched/triple-negative) and methods of axillary management (i.e. sentinel lymph node biopsy/axillary lymph node dissection). The primary outcome is DFS. The secondary outcomes include DFS according to molecular subtype, treatment-related toxicity, and patient's quality of life per EORTC QLQ-C30 and QLQ-BR23. Patients will be followed for survival and disease recurrence for seven years. A total of 1,926 patients are planned to be enrolled, with recruitment initiated in April 2017. As of June 2018, a total of 236 patients were enrolled.

Acknowledgement

This study was supported by a grant from the National R&D Program for Cancer Control, Ministry of Health & Welfare, Republic of Korea (grant number: HA17C0043010018).

Citation Format: Kim H, Park W, Choi DH, Ahn SJ, Kim SS, Kim ES, Lee JH, Lee KC, Kim JH, Lee H-S, Kim JH, Kim MY, Park HJ, Kim K, Song SH, Kwon J, Lee IJ, Kim TH, Kim TG, Chang AR, Cho O, Jeong BK, Ha B, Lee J, Ki Y. A phase 3 study of post-lumpectomy radiotherapy to whole breast + regional lymph nodes vs whole breast alone for patients with pN1 breast cancer treated with taxane-based chemotherapy (KROG 1701): Trial in progress [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-04-02.

Impact of antimicrobial treatment duration on outcome of Staphylococcus aureus bacteraemia: a cohort study

OBJECTIVES

To assess the outcome of Staphylococcus aureus bacteraemia (SAB) according to factors associated with necessity for longer treatment in conjunction with the duration of treatment.

METHODS

We prospectively collected the data of patients with SAB consecutively during 12 to 39 months from 11 hospitals. If multiple episodes of SAB occurred in one patient, only the first episode was enrolled. Factors associated with necessity for longer treatment were defined as follows: persistent bacteraemia, metastatic infection, prosthesis and endocarditis. If any of the factors were present, then the case was defined as longer antibiotic treatment warranted (LW) group; those without any factors were defined as shorter antibiotic treatment sufficient (SS) group. Poor outcome was defined as a composite of 90-day mortality or 30-day recurrence. Duration of antibiotic administration was classified as <14 or ≥14 days in the SS group and <28 or ≥28 days in the LW group.

RESULTS

Among 2098 cases, the outcome was analysed in 1866 cases, of which 591 showed poor outcome. The SS group accounted for 964 cases and the LW group for 852. On multivariate analysis, age over 65 years, pneumonia, higher Sequential Organ Failure Assessment (SOFA) score and chronic liver diseases were risk factors for poor outcome. Administration of antibiotics less than the recommendation was associated with poor outcome, but this significance was observed only in the LW group (adjusted odds ratio = 1.68; 95% confidence interval, 1.00-2.83; p 0.05).

CONCLUSIONS

Inappropriately short antibiotic treatment was associated with poor outcome in the LW group. Vigilant evaluation for risk factors to determine the duration of treatment may improve the outcome among patients with SAB.

Tumor-associated macrophages secrete CCL2 and induce the invasive phenotype of human breast epithelial cells through upregulation of ERO1-α and MMP-9

Tumor-associated macrophages (TAMs) are major components of tumor microenvironment that promote invasion and metastasis of cancer cells. In this study, we investigated the effect of TAMs on phenotypic conversion of non-neoplastic MCF10A human breast epithelial cells using an indirect co-culture system. Co-culture with TAMs induced epithelial-to-mesenchymal transition, invasive phenotype, and MMP-9 upregulation in MCF10A cells. Comparative proteomic analysis revealed that endoplasmic reticulum oxidoreductase (ERO)1-α was increased in MCF10A cells co-cultured with TAMs compared to that in mono-cultured cells. ERO1-α was crucial for TAMs-induced invasive phenotype and MMP-9 upregulation involving transcription factors c-fos and c-Jun. Cytokine array analysis showed that levels of interleukin (IL)-6, C-X-C motif ligand (CXCL)1, C-C motif ligand (CCL)2, growth-regulated protein (GRO), IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF) were increased in conditioned media of co-cultured cells. Among these cytokines increased in conditioned media of co-cultured cells, CCL2 was secreted from TAMs, leading to induction of ERO1-α, MMP-9 upregulation, and invasiveness in MCF10A cells. Our findings elucidated a molecular mechanism underlying the aggressive phenotypic change of non-neoplastic breast cells by co-culture with TAMs, providing useful information for prevention or treatment of recurrent breast cancer.

Active surveillance for carbapenem-resistant Enterobacteriaceae, vancomycin-resistant enterococci and toxigenic Clostridium difficile among patients transferred from long-term care facilities in Korea

A 10-month active surveillance study was conducted to assess carriage of carbapenemase-producing Enterobacteriaceae (CPE), vancomycin-resistant enterococci (VRE) and toxigenic Clostridium difficile colonization among patients transferred to hospital from long-term care facilities (LTCFs). Four (1.4%) patients with carbapenem-resistant Enterobacteriaceae (none of which were CPE), 59 (21%) patients with VRE and 20 (7.1%) patients colonized with toxigenic C. difficile were identified from 282 rectal specimens. There was no outbreak of VRE infection during the study period. The low prevalence of CPE carriage suggests that screening all admissions from LTCFs for CPE would not be cost-effective, and that screening and use of contact precautions for VRE should be reconsidered.

Concordance of results of blood and tissue cultures from patients with pyogenic spondylitis: a retrospective cohort study

OBJECTIVES

To investigate the concordance of results of blood and tissue cultures in patients with pyogenic spondylitis.

METHODS

We searched for patients with pyogenic spondylitis in whom microorganisms were isolated from both blood and tissue cultures by retrospective review of medical records in three tertiary university-affiliated hospitals between January 2005 and December 2015. The species and antimicrobial susceptibility patterns of isolates from blood and tissue cultures were compared.

RESULTS

Among 141 patients with pyogenic spondylitis in whom microorganisms were isolated from both blood and tissue cultures, the species of blood and tissue isolates were identical in 135 patients (95.7%, 135/141). Excluding the four anaerobic isolates, we investigated antimicrobial susceptibility patterns of 131 isolates of the same species from blood and tissue cultures. Antibiotic susceptibility patterns were identical in 128 patients (97.7%, 128/131). The most common isolates were Staphylococcus aureus (86 patients; 85 concordant and one discordant), followed by streptococcus (24 patients; 22 concordant and two discordant), and Escherichia coli (eight patients; all concordant).

CONCLUSIONS

We suggest that a positive blood culture from patients with pyogenic spondylitis could preclude the need for additional tissue cultures, especially when S. aureus and streptococcus grew in blood cultures.

agr functionality affects clinical outcomes in patients with persistent methicillin-resistant Staphylococcus aureus bacteraemia

Methicillin-resistant Staphylococcus aureus bacteremia (MRSAB) often persists despite appropriate antibiotic therapy. It is unclear what microbiological factors contribute to poor clinical outcomes in persistent MRSAB (pMRSAB). We aimed to identify clinical and microbiological risk factors for in-hospital mortality in pMRSAB. We analysed MRSAB cases prospectively collected between 2009 and 2016 at 11 hospitals in Korea, defining cases of pMRSAB as MRSAB lasting ≥5 days despite administration of effective antibiotics. The first blood isolates from the pMRSAB cases were tested for staphylococcal cassette chromosome mec type, staphylococcal protein A type, accessary gene regulator (agr) type, genes for Panton-Valentine leukocidin and phenol-soluble modulin-mec, vancomycin minimum inhibitory concentration, vancomycin heteroresistance, and agr functionality. We also collected clinical information for each case. Of 960 MRSAB cases, 152 pMRSAB were finally eligible. Univariable analysis revealed that in-hospital mortality was significantly associated with Charlson's comorbidity-weighted index (CCWI) score, Pitt bacteremia score, sequential organ failure assessment score, presentation with septic shock, pneumonia, agr dysfunction, and vancomycin heteroresistance. Bone and joint infections were negatively associated with in-hospital mortality. Multivariable analysis revealed the following independent risk factors for in-hospital mortality: CCWI score [adjusted odds ratio (aOR), per one point, 1.25; 95% confidence interval (CI), 1.08-1.44; P = 0.003), Pitt bacteremia score (aOR, per one point, 1.33; 95% CI, 1.09-1.62; P = 0.005), non-eradicated foci of infection (aOR, 3.12; 95% CI, 1.18-8.27; P = 0.022), and agr dysfunction (aOR, 2.48; 95% CI, 1.12-5.47; P = 0.025). agr dysfunction is an independent risk factor for in-hospital mortality in pMRSAB.

Evaluation of the chronic disease management program for appropriateness of medication adherence and persistence in hypertension and type-2 diabetes patients in Korea

The chronic disease management program (CDMP), a multilevel intervention including copayment reduction and physician incentives, was introduced in 2012 in Korea to improve blood pressure and glycemic control by strengthening the function of clinic as primary care institutions in managing hypertension and diabetes. This study, therefore, aimed to evaluate the effect of CDMP on the appropriateness of medication adherence and persistence in hypertension or type-2 diabetes patients.A pre-post retrospective study was conducted using claims cohort data from 2010 to 2013. Hypertension or type-2 diabetes patients were selected as the CDMP group, while dyslipidemia patients were the control group. Study groups were further categorized as clinic shifters or non-shifters on the basis of whether hospital use changed to clinic use during the study period. Pre-post changes in adherence and persistence were assessed. Adherence was measured by medication possession ratio (MPR) and categorized as under (<0.8), appropriate (0.8-1.1), and over-adherence (>1.1). Persistence was measured by 12-month cumulative persistence rate.The pre-post change was significantly improved for appropriate-adherence (hypertension, +6.0%p; diabetes, +6.1%p), 12-month cumulative persistence (hypertension, +6.5%p; diabetes, +10.8%p), and over-adherence (hypertension, -5.3%p; diabetes, -2.8%p) only among the shifters in the CDMP group. Among these, patients visiting the same, single clinic showed a significant increase in appropriate-adherence, whereas those who changed their clinics showed a nonsignificant increase. No significant improvement was verified among the non-shifters in the CDMP group.CDMP improved medication adherence and persistence by significantly increasing appropriate-adherence and 12-month cumulative persistence rate in hypertension and type-2 diabetes patients. Particularly, CDMP significantly improved over-adherence, which was associated with increasing healthcare costs and hospitalization risk.

Phenotypic changes of methicillin-resistant Staphylococcus aureus during vancomycin therapy for persistent bacteraemia and related clinical outcome

Persistent bacteraemia (PB) due to methicillin-resistant Staphylococcus aureus (MRSA) that fails to respond to glycopeptide therapy is a well-documented clinical problem. There are limited data on changes in agr functionality, vancomycin susceptibility and heteroresistance during MRSA PB. Thus, the frequency of these changes and their clinical significance remain unclear. Only patients with MRSA PB (≥7 days) from a prospective cohort of S. aureus bacteraemia were included. We collected isogenic paired strains and compared vancomycin MIC, vancomycin heteroresistance, and agr functionality between initial and final blood isolates. We also assessed the clinical outcome. A total of 49 patients had MRSA PB over 22 months. Bacteraemia persisted for a median of 13 days and most patients (98%) received glycopeptide as initial therapy. Among 49 isogenic pairs, only one pair showed a vancomycin MIC increase ≥2-fold by broth microdilution method, and only seven (14%) by E-test. Significant portions of initial isolates had vancomycin heteroresistance (49%) and agr dysfunction (76%). Development of vancomycin heteroresistance during PB occurred in four (16%) among 25 initial vancomycin-susceptible isolates, and acquisition of agr dysfunction occurred in two (16%) among 12 initial agr-functional isolates. Changes in the opposite direction occasionally occurred. These phenotypic changes during PB were not associated with mortality, whereas agr dysfunction of the initial isolates was significantly associated with mortality. During MRSA PB, phenotypic changes of MRSA isolates occurred occasionally under prolonged vancomycin exposure but were not significantly associated with clinical outcome. In contrast, initial agr dysfunction could be a predictor for mortality in MRSA PB.

Characterization of micro-resonator based on enhanced metal insulator semiconductor capacitor for glucose recognition

We present a concept for the characterization of micro-fabricated based resonator incorporating air-bridge metal-insulator-semiconductor (MIS) capacitor to continuously monitor an individual's state of glucose levels based on frequency variation. The investigation revealed that, the micro-resonator based on MIS capacitor holds considerable promise for implementation and recognition as a glucose sensor for human serum. The discrepancy in complex permittivity as a result of enhanced capacitor was achieved for the detection and determination of random glucose concentration levels using a unique variation of capacitor that indeed results in an adequate variation of the resonance frequency. Moreover, the design and development of micro-resonator with enhanced MIS capacitor generate a resolution of 112.38 × 10^-3pF/mg/dl, minimum detectable glucose level of 7.45mg/dl, and a limit of quantification of 22.58mg/dl. Additionally, this unique approach offers long-term reliability for mediator-free glucose sensing with a relative standard deviation of less than 0.5%.

National reimbursement listing determinants of new cancer drugs: a retrospective analysis of 58 cancer treatment appraisals in 2007-2016 in South Korea

BACKGROUND

Since the positive-list system was introduced, concerns have been raised over restricting access to new cancer drugs in Korea. Policy changes in the decision-making process, such as risk-sharing agreement and the waiver of pharmacoeconomic data submission, were implemented to improve access to oncology medicines, and other factors are also involved in the reimbursement for cancer drugs. The aim of this study is to investigate the reimbursement listing determinants of new cancer drugs in Korea.

METHODS

All cancer treatment appraisals of Health Insurance Review and Assessment during 2007-2016 were analyzed based on 13 independent variables (comparative effectiveness, cost-effectiveness, drug-price comparison, oncology-specific policy, and innovation such as new mode of action). Univariate and multivariate logistic analyses were conducted.

RESULTS

Of 58 analyzed submissions, 40% were listed in the national reimbursement formulary. In univariate analysis, four variables were related to listing: comparative effectiveness, drug-price comparison, new mode of action, and risk-sharing agreement. In multivariate logistic analysis, three variables significantly increased the likelihood of listing: clinical improvement, below alternative's price, and risk-sharing arrangement. Cancer drug's listing increased from 17% to 47% after risk-sharing agreement implementation.

CONCLUSION

Clinical improvement, cost-effectiveness, and RSA application are critical to successful national reimbursement listing.

A portable and reconfigurable multi-organ platform for drug development with onboard microfluidic flow control

The drug development pipeline is severely limited by a lack of reliable tools for prediction of human clinical safety and efficacy profiles for compounds at the pre-clinical stage. Here we present the design and implementation of a platform technology comprising multiple human cell-based tissue models in a portable and reconfigurable format that supports individual organ function and crosstalk for periods of up to several weeks. Organ perfusion and crosstalk are enabled by a precision flow control technology based on electromagnetic actuators embedded in an arrayed format on a microfluidic platform. We demonstrate two parallel circuits of connected airway and liver modules on a platform containing 62 electromagnetic microactuators, with precise and controlled flow rates as well as functional biological metrics over a two week time course. Technical advancements enabled by this platform include the use of non-sorptive construction materials, enhanced scalability, portability, flow control, and usability relative to conventional flow control modes (such as capillary action, pressure heads, or pneumatic air lines), and a reconfigurable and modular organ model format with common fluidic port architecture. We demonstrate stable biological function for multiple pairs of airway-liver models for periods of 2 weeks in the platform, with precise control over fluid levels, temperature, flow rate and oxygenation in order to support relevant use cases involving drug toxicity, efficacy testing, and organ-organ interaction.

Effect of Sodium-Glucose Co-Transporter 2 Inhibitor, Dapagliflozin, on Renal Renin-Angiotensin System in an Animal Model of Type 2 Diabetes

Background

Renal renin-angiotensin system (RAS) activation is one of the important pathogenic mechanisms in the development of diabetic nephropathy in type 2 diabetes. The aim of this study was to investigate the effects of a sodium-glucose co-transporter 2 (SGLT-2) inhibitor, dapagliflozin, on renal RAS in an animal model with type 2 diabetes.

Methods

Dapagliflozin (1.0 mg/kg, OL-DA) or voglibose (0.6 mg/kg, OL-VO, diabetic control) (n = 10 each) was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats for 12 weeks. We used voglibose, an alpha-glucosidase inhibitor, as a comparable counterpart to SGLT2 inhibitor because of its postprandial glucose-lowering effect without proven renoprotective effects. Control Long-Evans Tokushima Otsuka (LT) and OLETF (OL-C) rats received saline (n = 10, each). Changes in blood glucose, urine albumin, creatinine clearance, and oxidative stress were measured. Inflammatory cell infiltration, mesangial widening, and interstitial fibrosis in the kidney were evaluated by histological analysis. The effects of dapagliflozin on renal expression of the RAS components were evaluated by quantitative RT-PCR in renal tissue.

Results

After treatment, hyperglycemia and urine microalbumin levels were attenuated in both OL-DA and OL-VO rather than in the OL-C group (P < 0.05). The urine angiotensin II (Ang II) and angiotensinogen levels were significantly decreased following treatment with dapagliflozin or voglibose, but suppression of urine Ang II level was more prominent in the OL-DA than the OL-VO group (P < 0.05). The expressions of angiotensin type 1 receptor and tissue oxidative stress markers were markedly increased in OL-C rats, which were reversed by dapagliflozin or voglibose (P < 0.05, both). Inflammatory cell infiltration, mesangial widening, interstitial fibrosis, and total collagen content were significantly increased in OL-C rats, which were attenuated in OL-DA group (P < 0.05).

Conclusion

Dapagliflozin treatment showed beneficial effects on diabetic nephropathy, which might be via suppression of renal RAS component expression, oxidative stress and interstitial fibrosis in OLETF rats. We suggest that, in addition to control of hyperglycemia, partial suppression of renal RAS with an SGLT2 inhibitor would be a promising strategy for the prevention of treatment of diabetic nephropathy.

Remote Ischemic Preconditioning for the Prevention of Contrast-Induced Acute Kidney Injury in Diabetics Receiving Elective Percutaneous Coronary Intervention

Objective

Remote ischemic preconditioning (RIPC) induces transient episodes of ischemia by the occlusion of blood flow in non-target tissue, before a subsequent ischemia-reperfusion injury. When RIPC is applied before percutaneous coronary intervention (PCI), the kidneys may be protected against ischemia-reperfusion injury and subsequently contrast-induced acute kidney injury (CI-AKI). The aim of this study was to evaluate the efficacy of RIPC for the prevention of CI-AKI in patients with diabetes with pre-existing chronic kidney disease (CKD) undergoing elective PCI.

Methods

This randomized, double-blind, sham-controlled study enrolled patients with diabetes scheduled for elective PCI with eGFR ≤60 ml/min/1.73 m² or urinary albumin creatinine ratio of >300 mg/g to receive either RIPC or the sham ischemic preconditioning.

Results

One hundred and two patients (68.9 ± 8.2 years old, 47.1% men) were included. Baseline eGFR, creatinine and serum NGAL was similar between RIPC and control groups (48.5 ± 12 ml/min vs. 46.6 ± 10 ml/min, p = 0.391; 1.42 ± 0.58 mg/dl vs. 1.41 ± 0.34 mg/dl, p = 0.924; and 136.0 ± 45.0 ng/ml vs. 137.6 ± 43.3 ng/ml, p = 0.961, respectively). CI-AKI occurred in 13.7% (14/102) of the total subjects, with both RIPC and control groups having an equal incidence of 13.7% (7/51). No significant differences were seen in creatinine, NGAL, cardiac enzymes (troponin T, CKMB) and hs-CRP between the groups post-procedure.

Conclusions

In this study, RIPC applied prior to elective PCI was not effective in preventing CI-AKI in patients with diabetes with pre-existing CKD.

Trial Registration

ClinicalTrials.gov NCT02329444

Surveillance of the Middle East respiratory syndrome (MERS) coronavirus (CoV) infection in healthcare workers after contact with confirmed MERS patients: incidence and risk factors of MERS-CoV seropositivity

Given the mode of transmission of Middle East respiratory syndrome (MERS), healthcare workers (HCWs) in contact with MERS patients are expected to be at risk of MERS infections. We evaluated the prevalence of MERS coronavirus (CoV) immunoglobulin (Ig) G in HCWs exposed to MERS patients and calculated the incidence of MERS-affected cases in HCWs. We enrolled HCWs from hospitals where confirmed MERS patients had visited. Serum was collected 4 to 6 weeks after the last contact with a confirmed MERS patient. We performed an enzyme-linked immunosorbent assay (ELISA) to screen for the presence of MERS-CoV IgG and an indirect immunofluorescence test (IIFT) to confirm MERS-CoV IgG. We used a questionnaire to collect information regarding the exposure. We calculated the incidence of MERS-affected cases by dividing the sum of PCR-confirmed and serology-confirmed cases by the number of exposed HCWs in participating hospitals. In total, 1169 HCWs in 31 hospitals had contact with 114 MERS patients, and among the HCWs, 15 were PCR-confirmed MERS cases in study hospitals. Serologic analysis was performed for 737 participants. ELISA was positive in five participants and borderline for seven. IIFT was positive for two (0.3%) of these 12 participants. Among the participants who did not use appropriate personal protective equipment (PPE), seropositivity was 0.7% (2/294) compared to 0% (0/443) in cases with appropriate PPE use. The incidence of MERS infection in HCWs was 1.5% (17/1169). The seroprevalence of MERS-CoV IgG among HCWs was higher among participants who did not use appropriate PPE.

Evaluation of Circulating Markers of Neutrophil Extracellular Trap (NET) Formation as Risk Factors for Diabetic Retinopathy in a Case-Control Association Study

Background: Inflammatory stimuli can induce neutrophils to release nuclear DNA combined with histones into the extracellular space, forming neutrophil extracellular traps. Because inflammation contributes to diabetic retinopathy, it is plausible that neutrophil extracellular trap formation actively occurs in diabetic retinopathy. This case-control study investigated the clinical relevance of circulating levels of neutrophil extracellular trap components as risk factors of diabetic retinopathy, and further evaluated whether glucose induced neutrophil extracellular trap formation in vitro using whole blood from healthy volunteers. Methods: Circulating levels of DNA-histone complexes, cell free double-stranded DNA, and polymorphonuclear neutrophil elastase, considered to be markers of neutrophil extracellular trap formation, were measured in patients with diabetic retinopathy (n=28) and without (n=62) and in 28 healthy controls. Results: Circulating DNA-histone complex and polymorphonuclear neutrophil elastase levels were significantly increased in patients with diabetic retinopathy compared with those without retinopathy. Multivariable logistic regression analysis, adjusted for glycated hemoglobin levels and fasting blood glucose, revealed that DNA-histone complex and polymorphonuclear neutrophil elastase levels were significant independent risk factors of retinopathy. In vitro experiments also showed that glucose significantly increased markers of neutrophil extracellular trap formation in a dose-dependent manner. Conclusions: Markers of neutrophil extracellular trap formation were independent risk factors of diabetic retinopathy. This finding provides a new insight into the potential therapeutic and preventive approaches to dampen neutrophil extracellular trap formation.

Patiromer: A Review in Hyperkalaemia

Patiromer (Veltassa(™)) for oral suspension is a sodium-free potassium binder that is approved in the USA for the treatment of hyperkalaemia. In clinical trials, patiromer significantly reduced serum potassium levels from baseline to week 4 in patients with chronic kidney disease (CKD) and mild to severe hyperkalaemia (OPAL-HK), or CKD, mild to moderate hyperkalaemia and type 2 diabetes mellitus (AMETHYST-DN), who were receiving renin-angiotensin-aldosterone system inhibitors (RAASis; drugs that inhibit the renal excretion of potassium). Among patients in OPAL-HK who had moderate to severe hyperkalaemia at baseline and normokalaemia on patiromer and RAASis at week 4, continuing patiromer for a further 8 weeks maintained reductions in potassium levels more effectively than switching to placebo (i.e. withdrawing patiromer); consequently, fewer patiromer than placebo recipients experienced recurrent hyperkalaemia during this period. Furthermore, almost all patiromer (vs. less than half of placebo) recipients were still receiving RAASi therapy at the end of this trial. In AMETHYST-DN, the significant reduction from baseline in serum potassium levels seen at week 4 was sustained for up to 52 weeks. Patiromer was generally well tolerated in these trials, with no treatment-related serious adverse events or deaths. Commonly occurring treatment-related adverse events include mild to moderate constipation and hypomagnesaemia, and there is a low risk of hypokalaemia. In conclusion, oral patiromer is a useful new option for patients with hyperkalaemia.

A novel role for flotillin-1 in H-Ras-regulated breast cancer aggressiveness

Elevated expression and aberrant activation of Ras have been implicated in breast cancer aggressiveness. H-Ras, but not N-Ras, induces breast cell invasion. A crucial link between lipid rafts and H-Ras function has been suggested. This study sought to identify the lipid raft protein(s) responsible for H-Ras-induced tumorigenicity and invasiveness of breast cancer. We conducted a comparative proteomic analysis of lipid raft proteins from invasive MCF10A human breast epithelial cells engineered to express active H-Ras and non-invasive cells expressing active N-Ras. Here, we identified a lipid raft protein flotillin-1 as an important regulator of H-Ras activation and breast cell invasion. Flotillin-1 was required for epidermal growth factor-induced activation of H-Ras, but not that of N-Ras, in MDA-MB-231 triple-negative breast cancer (TNBC) cells. Flotillin-1 knockdown inhibited the invasiveness of MDA-MB-231 and Hs578T TNBC cells in vitro and in vivo. In xenograft mouse tumor models of these TNBC cell lines, we showed that flotillin-1 played a critical role in tumor growth. Using human breast cancer samples, we provided clinical evidence for the metastatic potential of flotillin-1. Membrane staining of flotillin-1 was positively correlated with metastatic spread (p = 0.013) and inversely correlated with patient disease-free survival rates (p = 0.005). Expression of flotillin-1 was associated with H-Ras in breast cancer, especially in TNBC (p < 0.001). Our findings provide insight into the molecular basis of Ras isoform-specific interplay with flotillin-1, leading to tumorigenicity and aggressiveness of breast cancer.

Expression of autotaxin and lysophosphatidic acid receptors 1 and 3 in the developing rat lung and in response to hyperoxia

We sought to evaluate lysophosphatidic acid (LPA) signaling improvement in lung development by assessing the expression of autotaxin and LPA receptor 1 and 3 (LPAR1 and LPAR3) in the neonatal rat lung during normal perinatal development and in response to hyperoxia. In the developmental study, rats were sacrificed on days 17, 19, and 21 of gestation; on postnatal days 1, 4, and 7; and at adulthood (postnatal 9 weeks). In the hyperoxia study, 42 postnatal 4-day-old rat pups were divided into seven groups and exposed to either 85% O2 for 24, 72, or 120 h or room air for 0, 24, 72, or 120 h. The rats were then euthanized after 0, 24, 72, and 120 h of exposure. Immunofluorescence demonstrated that autotaxin, LPAR1, and LPAR3 proteins were broadly colocalized in airway epithelial cells, but mainly distributed in vascular endothelial and mesenchymal cells during the first postnatal week. The expression of autotaxin, LPAR1, and LPAR3 were increased during late gestation and then decreased after birth. Autotaxin expression and enzymatic activity were significantly increased at 72 and 120 h after exposure to hyperoxia. LPAR1 and LPAR3 expression was also increased after 120 h of hyperoxic exposure. These findings suggest that LPA-associated molecules were upregulated at birth and induced by hyperoxia in the developing rat lung. Therefore, the LPA pathway may be involved in normal lung development, including vascular development, as well as wound-healing processes of injured neonatal lung tissue, which is at risk of neonatal hyperoxic acute lung injury.

The MDM2 small-molecule inhibitor RG7388 leads to potent tumor inhibition in p53 wild-type neuroblastoma

Neuroblastoma is an aggressive pediatric malignancy which is >98% p53 wild-type at diagnosis. As a primary repressor of p53 activity and part of a p53-activated negative feedback loop, targeting of mouse double minute 2 homolog (MDM2) is an attractive therapeutic approach to reactivation of p53. Since development of the first selective MDM2 inhibitor, Nutlin-3a, newer compounds have been developed for increased potency and improved bioavailability. Herein, we sought to determine the efficacy and specificity of a second-generation MDM2 inhibitor, RG7388, in neuroblastoma cell lines and xenografts and examine its effect on the p53-independent pathway of hypoxia-inducible factor-1 alpha (HIF-1α)/vascular endothelial growth factor (VEGF). Cell viability and apoptosis studies were performed on the neuroblastoma cell lines, NGP, SH-SY5Y, LAN-5, LAN-5 si-p53 (p53 silenced), and SK-N-AS (p53 null). RG7388 potently decreased cell proliferation and activated p53-dependent apoptosis. Tumor-bearing mice treated with RG7388 demonstrated significant tumor inhibition by 59% in NGP (P=0.003), 67% in SH-SY5Y (P=0.006), and 75% in LAN-5 (P=0.0019) p53 wild-type xenograft tumors, but no inhibitory effect on LAN-5 si-p53 or SK-N-AS p53-silenced/null xenograft tumors. Moreover, RG7388 was found to inhibit the p53-independent pathway of HIF-1α/VEGF with decreased gene expression and alteration of angiogenesis. Our study supports the further evaluation of RG7388 as a novel treatment option in p53 wild-type neuroblastoma at diagnosis and relapse.

High normal albuminuria is associated with arterial stiffness and carotid atherosclerosis in Korean patients with type 2 diabetes

BACKGROUND AND AIMS

Current evidence suggests that high normal albuminuria is significantly associated with increased cardiovascular risk. This study investigated the association between urine albumin-to-creatinine ratio (ACR) within the normal range and subclinical atherosclerosis in Korean patients with type 2 diabetes.

METHODS AND RESULTS

This cross-sectional study involved 521 type 2 diabetic patients with normoalbuminuria. Brachial-ankle pulse wave velocity (baPWV) measurement and ultrasound assessment of carotid atherosclerosis was done. Subclinical atherosclerosis was assessed by the presence of high baPWV (>1682 cm/s), carotid atherosclerosis (intima-media thickness >0.8 mm or the presence of plaques), and carotid stenosis (≥50% of luminal narrowing). Across the tertiles of ACR, there was a trend for an increasing prevalence of high baPWV (16.8%, 20.0%, and 38.2%, P < 0.001), carotid atherosclerosis (46.9%, 55.4%, and 64.7%, P < 0.001), and carotid stenosis (12.7%, 16.0%, and 30.1%, P < 0.001). In multivariate analysis, patients in the highest ACR tertile had an odds ratio of 2.05 (95% confidence interval [CI], 1.13-3.72, P = 0.019) for high baPWV, 1.78 (95% CI, 1.08-2.93, P = 0.024) for carotid atherosclerosis, and 2.72 (95% CI, 1.44-5.11, P = 0.002) for carotid stenosis compared to those in the lowest tertile. The relation of ACR with carotid atherosclerosis and stenosis remained significant even in patients without diabetic retinopathy.

CONCLUSION

High normal albuminuria was significantly associated with atherosclerotic vascular changes, independent of retinopathy and other cardiovascular risk factors. High normal albuminuria may be an early marker for subclinical atherosclerosis in type 2 diabetes.