Therapeutic efficacy of an alpha-particle emitter labeled anti-GD2 humanized antibody against osteosarcoma-a proof of concept study

PURPOSE

Current treatments for osteosarcoma (OS) have a poor prognosis, particularly for patients with metastasis and recurrence, underscoring an urgent need for new targeted therapies to improve survival. Targeted alpha-particle therapy selectively delivers cytotoxic payloads to tumors with radiolabeled molecules that recognize tumor-associated antigens. We have recently demonstrated the potential of an FDA approved, humanized anti-GD2 antibody, hu3F8, as a targeted delivery vector for radiopharmaceutical imaging of OS. The current study aims to advance this system for alpha-particle therapy of OS.

METHODS

The hu3F8 antibody was radiolabeled with actinium-225, and the safety and therapeutic efficacy of the [225Ac]Ac-DOTA-hu3F8 were evaluated in both orthotopic murine xenografts of OS and spontaneously occurring OS in canines.

RESULTS

Significant antitumor activity was proven in both cases, leading to improved overall survival. In the murine xenograft's case, tumor growth was delayed by 16-18 days compared to the untreated cohort as demonstrated by bioluminescence imaging. The results were further validated with magnetic resonance imaging at 33 days after treatment, and microcomputed tomography and planar microradiography post-mortem. Histological evaluations revealed radiation-induced renal toxicity, manifested as epithelial cell karyomegaly and suggestive polyploidy in the kidneys, suggesting rapid recovery of renal function after radiation damage. Treatment of the two canine patients delayed the progression of metastatic spread, with an overall survival time of 211 and 437 days and survival beyond documented metastasis of 111 and 84 days, respectively.

CONCLUSION

This study highlights the potential of hu3F8-based alpha-particle therapy as a promising treatment strategy for OS.

Differentiation between atypical anorexia nervosa and anorexia nervosa using machine learning

OBJECTIVE

Body mass index (BMI) is the primary criterion differentiating anorexia nervosa (AN) and atypical anorexia nervosa despite prior literature indicating few differences between disorders. Machine learning (ML) classification provides us an efficient means of accurately distinguishing between two meaningful classes given any number of features. The aim of the present study was to determine if ML algorithms can accurately distinguish AN and atypical AN given an ensemble of features excluding BMI, and if not, if the inclusion of BMI enables ML to accurately classify between the two.

METHODS

Using an aggregate sample from seven studies consisting of individuals with AN and atypical AN who completed baseline questionnaires (N = 448), we used logistic regression, decision tree, and random forest ML classification models each trained on two datasets, one containing demographic, eating disorder, and comorbid features without BMI, and one retaining all features and BMI.

RESULTS

Model performance for all algorithms trained with BMI as a feature was deemed acceptable (mean accuracy = 74.98%, mean area under the receiving operating characteristics curve [AUC] = 74.75%), whereas model performance diminished without BMI (mean accuracy = 59.37%, mean AUC = 59.98%).

DISCUSSION

Model performance was acceptable, but not strong, if BMI was included as a feature; no other features meaningfully improved classification. When BMI was excluded, ML algorithms performed poorly at classifying cases of AN and atypical AN when considering other demographic and clinical characteristics. Results suggest a reconceptualization of atypical AN should be considered.

PUBLIC SIGNIFICANCE

There is a growing debate about the differences between anorexia nervosa and atypical anorexia nervosa as their diagnostic differentiation relies on BMI despite being similar otherwise. We aimed to see if machine learning could distinguish between the two disorders and found accurate classification only if BMI was used as a feature. This finding calls into question the need to differentiate between the two disorders.

Red cabbage juice-mediated gut microbiota modulation improves intestinal epithelial homeostasis and ameliorates colitis

Gut microbiota plays a crucial role in inflammatory bowel disease (IBD) and has therapeutic benefits. Thus, targeting the gut microbiota is a promising therapeutic approach for IBD treatment. We recently found that red cabbage juice (RCJ) ameliorates dextran sulfate sodium (DSS)-induced colitis in mice. However, the underlying mechanisms remain unknown. The current study investigated the modulation of gut microbiota in response to treatment with RCJ to ameliorate the DSS colitis. The initial results demonstrated that mice treated with DSS + RCJ showed increased body weight and decreased diarrhea and blood in feces compared to the DSS alone group. RCJ ameliorated colitis by regulating the intestinal barrier function by reducing the number of apoptotic cells, improving colonic protective mucin, and increasing tight junction protein in RCJ + DSS groups compared to the DSS group. Short-gun metagenomic analysis revealed significant enrichment of short-chain fatty acid (SCFAs)-producing bacteria (Butyrivibrio, Ruminococcaceae, Acetatifactor muris, Rosburia Sp. CAG:303 , Dorea Sp. 5-2) increased PPAR-© activation, leading to repression of the nuclear factor κB (NFκB) signaling pathway, thus decreasing the production of crucial inflammatory cytokines and chemokines in the RCJ + DSS groups compared to the DSS group. Pathway abundance analysis showed an increased abundance of the SCFA pathway, reduced histidine degradation ( Bacteroides sartorii, and Bacteroides caecimuris ), and LCFA production in the RCJ+DSS treated group, suggesting the promotion of good colonic health. Furthermore, increased T-reg (FOXP3+) cells in the colon were due to SCFAs produced by the gut microbiota, which was corroborated by an increase in IL-10, a vital anti-inflammatory cytokine. Thus, our study provides the first evidence that RCJ ameliorates colonic inflammation by modulating the gut microbiota.

Abstract 1395: Humanized GD2 antibody for targeted radiopharmaceutical therapy of human and canine osteosarcoma

Osteosarcoma (OS) is the most frequently diagnosed bone tumor in children in the United States. The prognosis for metastatic or recurrent OS has remained poor (5-year survival<30%) with no new effective therapies developed during the past 30 years. The high expression of tumor antigen, ganglioside GD2, on a variety of tumors, including OS, with its restricted expression on normal tissue makes GD2 an ideal target for anti-OS radiopharmaceutical therapy. Since human and canine OS shares many biological and molecular features and the prevalence of OS in dogs is 27 times higher than that in humans, spontaneously occurring OS in dogs has been shown to be an ideal model for testing new treatments for human translation. In this study, we evaluated a humanized GD2 antibody, hu3F8, that was developed for neuroblastoma therapy, as a potential delivery vector for targeted radiopharmaceutical therapy of human and canine OS.The cross immunoreactivity of hu3F8 with canine OS cells (OSCA78) and tissue, and human OS cells was confirmed by immunohistochemistry staining and flow cytometry. The binding affinity of hu3F8 to GD2 was assessed in vitro in OSCA78 and IMR32 (a human neuroblastoma cell line known expressing GD2) cell lines using 111In-DTPA-hu3F8. The dissociation constant Kd was 7.4 ± 1.0 nM for OSCA78, and 6.2 ± 1.9 nM for IMR32. Biodistribution study was performed in Nu/Nu mice bearing either OSCA78 tumor or IMR32 tumor. At 24 h after 111In-DTPA-hu3F8 injection, the highest uptake was observed in the tumor, followed by the blood, spleen, lung, and kidneys. The mean tumor uptake was 12.0% ID/g for OSCA78 tumors and 15.0% ID/g for IMR32 tumors, with a tumor-to-muscle ratio of 10.6 and 21.1, and a tumor-to-blood ratio of 1.1 and 2.4, for OSCA78 and IMR32 tumors, respectively. The 72 h biodistribution study revealed the highest uptake of 111In-DTPA-hu3F8 in both OSCA78 (28.0% ID/g) and IMR32 (51.6% ID/g ) tumors, with a tumor-to-muscle ratio of 93.3 and 206.6, and a tumor-to-blood ratio of 6.7 and 8.4, for OSCA78 tumors and IMR32 tumors, respectively. The improved uptake of 111In-DTPA-hu3F8 in tumors at 72 h was indicative of selective binding of 111In-DTPA-hu3F8 to GD2 expressing tumors. SPECT imaging showed that both OSCA78 and IMR32 tumors with 111In-DTPA-hu3F8 had superior contrast to the background, while 111In-DTPA-Rituximab (an irrelevant antibody) injected OSCA78-bearing mouse only showed moderate contrast to the background in the kidney.The cross immunoreactivity and high binding affinity of hu3F8 to canine OS cells/tissue and its ability to deliver an imaging payload (111In) suggest that conjugating hu3F8 with a radionuclide, such as alpha-emitter, 225Ac, may provide a potent radiopharmaceutical therapy for human and canine OS.

Citation Format: Yingli Fu, Jing Yu, Ioanna Liatsou, Anders Josefsson, Yong Du, Jeffrey Bryan, Dara L. Kraitchman, George Sgouros. Humanized GD2 antibody for targeted radiopharmaceutical therapy of human and canine osteosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1395.

Policies, recommendations and training to respond to patient microaggressions and hate speech aimed at healthcare professionals: A systematic review

Introduction

Patient microaggressions and hate speech affect practitioners in all fields of healthcare. In some facilities, 100% of healthcare workers report experiencing harassment and hate speech, with the aggressors most frequently being patients. To date, there has been no systematic review of policies, recommendations and trainings on patient microaggressions and hate speech against healthcare professionals.

Objectives

A systematic review was conducted to identify recommendations and solutions for healthcare professionals on responding to patient microaggressions and hate speech. Additionally, websites of major healthcare professional organizations and the 6 largest healthcare systems were checked for policy statements related to discrimination by patients towards healthcare providers.

Methods

A literature search of PubMed, PsycINFO, Medline, ERIC and MedEdPORTAL. Articles that contained recommendations and trainings for responding to microaggressions and hate speech were retained. 13 Leading professional organizations and 6 healthcare systems were checked for policies on discrimination by patients.

Results

Our review identified 27 studies providing recommendations and trainings for healthcare professionals to address patient hate speech and microaggressions. Three professional organizations but no healthcare systems had policies on discrimination by patients.

Conclusions

Seven trainings that equip providers with tools to address patient microaggressions and hate speech were identified. Trainings included the ERASE framework; Stop, talk, and roll; interrupting microaggressions; and the OWTFD tool. Nineteen studies outlined recommendations for healthcare professionals and systems on how to respond to patient offenses. Professional organizations and healthcare systems need to create policies to support healthcare professionals who face microaggressions and hate speech.

Unusual presentation of appendicitis as soft tissue infection of the thigh

Appendicitis remains one of the most common causes of abdominal pain across the world typically presenting with right iliac fossa pain, fever and nausea or vomiting. We describe an unusual case of appendicitis presenting as a soft tissue infection of the thigh, thereby causing a delayed diagnosis from presentation. We discuss the pathophysiological process behind soft tissue infections caused by appendicitis and highlight investigation and management strategies to ensure prompt treatment to reduce patient mortality.

Synergizing sunitinib and radiofrequency ablation to treat hepatocellular cancer by triggering the antitumor immune response

Background

Minimally invasive radiofrequency ablation (RFA) is used as a first-line treatment option for hepatocellular cancer (HCC) with the weaknesses of incomplete ablation, tumor recurrence, and inferior outcomes. To overcome this limitation, we proposed to develop sunitinib-RFA integrated therapy with a potential of activating anti-HCC immune response.

Methods

Using our unique murine model, we developed a novel RFA platform with a modified human cardiac RF generator. Therapeutic efficacy of sunitinib–RFA combined treatment in HCC was tested in this platform. Tumor progression was monitored by MRI; tumor necrosis and apoptosis were detected by H&E and terminal deoxynucleotidyl transferase dUTP nick end labeling; immune reaction was defined by flow cytometry; and signaling molecules were examined with real-time PCR (qPCR), western blot, and immunohistochemical staining.

Results

A significantly reduced tumor growth and extended lift span were observed in the mice receiving combined treatment with RFA and sunitinib. This combined treatment significantly increased the frequency of CD8⁺ T cell, memory CD8⁺ T cell, and dendritic cells (DCs); decreased the frequency of regulatory T cells; and activated tumor-specific antigen (TSA) immune response in tumor microenvironment. We found that RFA caused PD-1 upregulation in tumor-infiltrated T cells by boosting hepatocyte growth factor (HGF) expression, which was suppressed by sunitinib treatment. We have also demonstrated that sunitinib suppressed VEGF’s effect in enhancing PD-L1 expression in DCs and attenuated heat-sink effect. The results indicate that RFA induced tumor destruction and release of in situ TSAs which can activate a tumoricidal immune response in sunitinib-treated mice, significantly improving anti-HCC therapeutic efficacy.

Conclusions

Sunitinib enables RFA-released in situ TSA to ignite an effective anti-tumor immune response by suppressing HGF and VEGF signaling pathways. Sunitinib–RFA as a synergistic therapeutic approach significantly suppresses HCC growth.

Symbiotic versus nonsymbiotic optimization for spatial and temporal degrees of freedom in pair creation

The field-induced decay of the quantum vacuum state associated with the creation of electron-positron pairs can be caused independently by either multiphoton transitions or by tunneling processes. The first mechanism is usually induced by appropriate temporal variations of the external field while the second (Schwinger-like) process occurs if a static but spatially dependent electric field is of supercritical strength. The ultimate goal is to construct an optimal space-time profile of an electromagnetic field that can maximize the creation of particle pairs. The simultaneous optimization of parameters that characterize the spatial and temporal features of both fields suggests that the optimal two-field configuration can be remarkably similar to that predicted from two independent optimizations for the spatial and temporal fields separately.

The mechanism of action of Russian propolis ethanol extracts against two antibiotic-resistant biofilm-forming bacteria

The interaction between antibiotic-resistant Staphylococcus aureus and antibiotic-sensitive Escherichia coli biofilm-forming bacteria and Russian propolis ethanol extracts was evaluated. In this study, bacterial cell death occurred when the cell membranes of bacteria interacted specifically with the antibacterial compounds found in propolis. In order to understand the Russian propolis ethanol extract mechanism of action, microscopy and bacterial lysis studies were conducted. Results uncovered from these experiments imply that the mechanism of action of Russian propolis ethanol extracts is structural rather than functional. The results obtained throughout this study demonstrate cell membrane damage, resulting in cell lysis and eventually bacterial death.

SIGNIFICANCE AND IMPACT OF THE STUDY

Most strains of bacteria and subsequently biofilms, have evolved and have altered their chemical composition in an attempt to protect themselves from antibiotics. The resistant nature of bacteria stems from the chemical rather than the physical means of inactivation of antibiotics. The results uncovered in this work demonstrate the potential application of Russian propolis ethanol extracts as a very efficient and effective method for bacterial and biofilm inactivation.

Abstract 4464: Effect of bacterial quorum sensing lactones on human pancreatic carcinoma cells

INTRODUCTION

Pancreatic cancer (PC) is the fourth leading cause of cancer related mortality in the United States. In spite of the discovery of gemcitabine, administered either alone or in combination with other drugs, the survival rate of 5% has remained unchanged for several decades now. In this study, we hypothesize that bacterial quorum sensing molecules such as N-3-oxo-dodecanoyl-L-homoserine lactone (O-DDHSL) could affect pancreatic carcinoma cell phenotype and characteristics. Elucidation of the mechanism of action of O-DDHSL could lead to the development of more effective analogs and novel therapeutic targets in PC.

MATERIALS AND METHODS

Human pancreatic carcinoma cells (Panc-1 and Aspc-1) was grown in DMEM-F12 media with 10% FBS at 37oC. Normal pancreatic ductal epithelial cells (HPDE) were maintained in keratinocyte serum free media. Total RNA was extracted from the cells and converted to cDNA which served as a template for qRT-PCR amplification in the presence of various gene primers. The effect of O-DDHSL on pancreatic carcinoma cell phenotype, apoptosis, viability, migration, proliferation and colony forming ability was investigated.

RESULTS

Both Panc-1 and Aspc-1 cell viability decreased in a concentration dependent manner in the presence of O-DDHSL (IC50 = 120 ± 5 μM; P ≤ 0.02) and (IC50 = 48 ± 8 μM; P ≤ 0.02), respectively. O-DDHSL had only minimal effect on HPDE cell viability. Apoptosis and inhibition of cell migration in Panc-1 and Aspc-1 cells was observed in the presence of O-DDHSL. Variable effect on migration associated genes such as IQGAP-1, cofilin and rhoC was noted in these cells upon O-DDHSL treatment as determined by qRT-PCR as well as protein expression by Western analysis.

CONCLUSIONS

In conclusion, the combined findings from our study demonstrate that O-DDHSL decreases pancreatic carcinoma cell viability, promotes apoptosis by activating caspases, and inhibits cell migration. O-DDHSL also modulates genes responsible for migration such as RhoC, cofilin and IQGAP-1 in these cells.

Citation Format: Senthil R. Kumar, Jeffrey Bryan. Effect of bacterial quorum sensing lactones on human pancreatic carcinoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4464. doi:10.1158/1538-7445.AM2015-4464

Abstract 4482: Development of localized cisplatin chemotherapy: from benchside to investigational new drug application

Many cancers preferentially spread to the lymphatics before systemic dissemination. The purpose of this study is to develop intralymphatically-targeted cisplatin nanoparticles for treating locally advanced head and neck cancer. This treatment methodology may significantly reduce the side effects and increase the efficacy of cisplatin-based chemotherapy in both humans and companion animals, compared to conventional intravenous chemotherapies. Cisplatin was chemically conjugated to hyaluronan (HA) to form hyaluronan-cisplatin (HA-Pt) nanoparticles. The nanoparticles were purified and concentrated using a tangential flow filtration system. The cisplatin substitution degree, particle size, molecular weight, viscosity, osmolality, sterility, bioburden, particulate content, impurity profiles, and stability of the formulation in the presence of various excipients were determined. All analytical methods utilized were fully validated according to FDA and/or USP guidelines. The pharmacokinetics, biodistribution and safety of subcutaneously injected HA-Pt were evaluated in animals. Anti-cancer efficacy of HA-Pt was determined in mice bearing cisplatin sensitive xenografts (1/wk for 3wks; 3.5mg/kg). Canines with spontaneously-occurring limb lymphomas were given a single 0.85-mg/kg subcutaneous dose peritumorally. Canines with spontaneously-occurring oral squamous cell carcinoma, oral melanoma, or nasal tumors received 3 doses at 10 to 15 mg/m2, peritumorally. The cisplatin conjugation degree on HA was 15-20 w/w%. HA-Pt demonstrated antiproliferative efficacy similar to standard cisplatin in vitro with sustained release of cisplatin (t1/2=10h). The characteristics of HA-Pt meet FDA requirements for injectable formulations. HA-Pt resulted in higher plasma area-under-the-curve (AUC) and lower Cmax in rats. Murine xenografts demonstrated improved complete and partial responses to HA-Pt treatment compared to standard cisplatin therapy. The HA-Pt reduced Cmax 5.5 fold and increased the canine plasma AUC of cisplatin 5.4 fold and the lymph node concentration 18 fold compared to i.v. cisplatin. The tumor:plasma ratio in canines was 429, indicating the nanoparticles concentrated drug within the tumor. A single injection of HA-Pt resulted in size reduction of the metastatic lymph nodes of canine oral melanoma. After the completion of 3 treatments, the canine oral tumor was completely eradicated (no recurrence within a year) and swelling was greatly reduced. Stable disease was observed for most of the dogs. This study demonstrates that subcutaneous delivery of HA-Pt formulations may be a promising treatment regimen to improve tumor drug accumulation and therapeutic efficacy. The successful completion of a series of GLP rodent and canine study will warrant a submission of an Investigational New Drug Application to the FDA.

Citation Format: Shuang Cai, Jeffrey Bryan, Daniel Aries, Laird Forrest. Development of localized cisplatin chemotherapy: from benchside to investigational new drug application. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4482. doi:10.1158/1538-7445.AM2014-4482

Abstract 398: Epigenetic changes in testis specific Y-like 5 gene in human prostate carcinoma: Gene expression analysis and its potential as a biomarker

INTRODUCTION

Testis specific Y-like protein (TSPYL-5) is a member of TSPY-L family of gene, whose functions are currently unknown. TSPYL-5 was reported to possess tumor suppressor function and a target for epigenetic silencing in human glioblastoma and colon carcinoma. The exact nature of TSPYL-5 gene expression and its epigenetic modification is not known in prostate carcinoma. We hypothesize that this gene could be expressed in prostate carcinoma cells and tissues and its methylation status could function as an epigenetic biomarker for aggressive prostate cancer phenotype.

MATERIALS AND METHODS

Human prostate carcinoma cells (PC3, DU145, LnCAP) was grown in DMEM-F12 media with 10% FBS at 37oC. Normal prostate epithelial cells (RWPE1-) were maintained in keratinocyte serum free media. Total RNA was extracted from the cells and converted to cDNA which served as a template for PCR amplification in the presence of TSPYL-5 gene primers. The amplified PCR products were analyzed by 2% agarose gel electrophoresis. Methylation-specific PCR (MSP) was performed with primers designed for the CpG island in the gene promoter to detect the methylation changes in the carcinoma cells.

RESULTS

Quantitative RT-PCR analysis of TSPYL-5 gene expression in different human prostate carcinoma cells lines identified 2-3 fold higher expression (P ≤ 0.005) in lines with metastatic propensity (PC3) compared to less aggressive ones. MSP analysis indicated differential promoter methylation of TSPYL-5 gene in carcinoma and normal prostate epithelial cells (RWPE1). Consistent methylation in LnCAP and DU145 cells was observed in our experiments and was associated with reduced expression of the gene.

CONCLUSIONS

Expression of TSPYL-5 is higher in human prostate carcinoma cells derived from more metastatic phenotype. This expression could be influenced by DNA methylation. It is not clear whether TSPYL-5 expression in prostate carcinoma cells could play a part in tumor suppressor function. Alternately, the presence of this gene may play alternate roles including treatment resistance and cell growth. Further, DNA methylation of the CpG island of TSPYL-5 could serve as a robust biomarker of aggressive phenotype in human prostate carcinoma.

Citation Format: Senthil R. Kumar, Jeffrey Bryan, Magda Esebua. Epigenetic changes in testis specific Y-like 5 gene in human prostate carcinoma: Gene expression analysis and its potential as a biomarker. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 398. doi:10.1158/1538-7445.AM2014-398

Recent Developments in Drug Therapy for Aplastic Anemia

Objective: This article reviews recent developments in immunosuppressive therapy (IST) for aplastic anemia (AA) patients who are not candidates for stem cell transplant (SCT); including, front-line, salvage, and novel treatment options with a focus on response rates (RRs) and overall survival (OS). Data Sources: A PubMed literature search was performed from 1977 to June 2014 using the search terms aplastic anemia, horse antithymocyte globulin (hATG), rabbit ATG (rATG), thymoglobulin, and cyclosporine (CSA). Additional references were identified from a review of literature citations. Study Selection and Data Extraction: All English-language studies investigating IST for treatment of AA in non–SCT candidates were evaluated. Data Synthesis: Studies indicate addition of CSA and corticosteroids to hATG for treatment of AA improves RRs, decreases relapse rates, and improves 5-year OS. hATG improved RRs, relapse rates, and OS compared to rATG in the front-line setting. Studies support the use of rATG when front-line IST with hATG fails or when hATG is unavailable. Front-line daclizumab can be considered for nonsevere AA (NAA); however, data is limited. Alemtuzumab or eltrombopag are options for relapsed AA in select patients. Conclusions: hATG with methylprednisolone and CSA is recommended for front-line treatment of AA, whereas rATG is reserved for salvage therapy. Front-line use of daclizumab has been studied in NAA patients, but additional prospective trials are needed before this is adopted into clinical practice. Alemtuzumab and eltrombopag have been studied for treatment of AA; recruiting is ongoing in clinical trials to assess the appropriate dosing strategy and place in therapy.

Clofarabine in the treatment of myelodysplastic syndromes

INTRODUCTION

Clofarabine is a second-generation purine nucleoside analog approved in 2004 for the treatment of pediatric patients with relapsed or refractory acute lymphocytic leukemia (ALL) following failure of at least two prior regimens. Clofarabine is a hybrid of fludarabine and cladribine, designed to overcome the pharmacologic limitations associated with its predecessors, while retaining their beneficial properties. In addition to providing a valuable treatment option for pediatric patients with ALL, clofarabine alone and in combination with cytarabine (Ara-C) has demonstrated substantial activity against myelodysplastic syndrome (MDS), thus rendering this agent a potential therapeutic option for MDS.

AREAS COVERED

This review focuses on the pharmacology and clinical activity of clofarabine in MDS, as well as its emerging role in the treatment of MDS. Publications in English were selected from the MEDLINE (PubMed) database, as well articles of interest from bibliographies and abstracts based on the publication of meeting materials.

EXPERT OPINION

DNA-methyltransferase inhibitors are the mainstay of therapy for many patients with MDS who require treatment. Although these agents are very well tolerated and represent a significant advancement in the treatment of MDS by improving transfusion requirements and prolonging survival in various subgroups of patients, response rates are modest and the duration of response is short. In addition to providing a valuable treatment option for pediatric ALL patients, clofarabine has substantial activity against MDS and is well tolerated by elderly patients, thus rendering it a potential therapeutic option.

End-of-study safety, immunogenicity, and efficacy of quadrivalent HPV (types 6, 11, 16, 18) recombinant vaccine in adult women 24-45 years of age

BACKGROUND

Previous analyses from a randomised trial in women aged 24-45 years have shown the quadrivalent human papillomavirus (qHPV) vaccine to be efficacious in the prevention of infection, cervical intraepithelial neoplasia (CIN), and external genital lesions (EGLs) related to HPV 6/11/16/18. In this report, we present end-of-study efficacy, safety, and immunogenicity data with a median follow-up time of 4.0 years.

METHODS

We enrolled 3819 24-45-year-old women with no history of cervical disease or genital warts in the past 5 years. Women received quadrivalent vaccine or placebo at day 1, and at months 2 and 6. Ascertainment of CIN/EGL was accomplished through Pap testing, genital inspection, and cervicovaginal sampling (every 6 months). The main analysis was conducted in a per-protocol efficacy population (that received three doses, was naive to the relevant HPV types at day 1, and remained free of infection through month 7). Efficacy was also estimated in other naive and non-naive populations.

RESULTS

Vaccine efficacy against the combined incidence of persistent infection, CIN/EGL related to HPV6/11/16/18 in the per-protocol population was 88.7% (95% CI: 78.1, 94.8). Efficacy for women who were seropositive and DNA negative for the relevant vaccine HPV type at the time of enrolment who received at least 1 dose was 66.9% (95% CI: 4.3, 90.6). At month 48, 91.5, 92.0, 97.4, and 47.9% of vaccinated women were seropositive to HPV 6/11/16/18, respectively. No serious vaccine-related adverse experiences were reported.

CONCLUSIONS

The qHPV vaccine demonstrated high efficacy, immunogenicity, and acceptable safety in women aged 24-45 years, regardless of previous exposure to HPV vaccine type.

Preliminary evidence for biologic activity of toceranib phosphate (Palladia(®)) in solid tumours

The purpose of this study was to provide an initial assessment of the potential biologic activity of toceranib phosphate (Palladia®, Pfizer Animal Health, Madison, NJ, USA) in select solid tumours in dogs. Cases in which toceranib was used to treat dogs with apocrine gland anal sac adenocarcinoma (AGASACA), metastatic osteosarcoma (OSA), thyroid carcinoma, head and neck carcinoma and nasal carcinoma were included. Clinical benefit (CB) was observed in 63/85 (74%) dogs including 28/32 AGASACA [8 partial response (PR), 20 stable disease (SD)], 11/23 OSAs (1 PR and 10 SD), 12/15 thyroid carcinomas (4 PR and 8 SD), 7/8 head and neck carcinomas [1 complete response (CR), 5 PR and 1 SD] and 5/7 (1 CR and 4 SD) nasal carcinomas. For dogs experiencing CB, the median dose of toceranib was 2.8 mg kg(-1) , 36/63 (58.7%) were dosed on a Monday/Wednesday/Friday basis and 47/63 (74.6%) were treated 4 months or longer. Although these data provide preliminary evidence that toceranib exhibits CB in dogs with certain solid tumours, future prospective studies are necessary to define its true activity.

Dairy consumption and metabolic syndrome: a systematic review of findings and methodological issues

A growing body of observational research suggests that dairy consumption may have a beneficial effect on the metabolic syndrome (MetS). MetS is a clustering of cardiometabolic risk factors within an individual that carries with it an increased risk of developing cardiovascular disease. A systematic search of electronic databases identified cross-sectional studies (n = 10) and prospective cohort studies (n = 3) that assessed dairy intake in relation to MetS. The quality of the included studies was assessed based on study methodology, measurement and reporting of dietary intake, use of standardized MetS diagnostic criteria and statistical analysis. Dairy intake was inversely associated with incidence or prevalence of MetS in seven out of 13 studies. Three studies found no association between dairy and MetS. Three studies reported mixed relationships between specific dairy foods and MetS. The majority of studies suggested a potential benefit of dairy consumption on the risk of having MetS, but methodological differences, potential biases and other limitations in the studies conducted prevent conclusions to be drawn. Future randomized controlled trials are needed to confirm the effect of dairy consumption on MetS.

Pharmacokinetic evaluation of decitabine for the treatment of leukemia

INTRODUCTION

Acute myeloid leukemia (AML) is a life-threatening malignancy that primarily afflicts an elderly population. Treatment of elderly patients with intensive chemotherapy is associated with high treatment-related morbidity and mortality. Therefore, less toxic approaches involving low-dose decitabine-based regimens are being explored in this patient population.

AREAS COVERED

This drug evaluation article discusses the rationale for targeting aberrant DNA methylation in hematologic malignancies, in particular the myelodysplastic syndromes (MDS) and AML. The authors review the pharmacokinetic data gained from low-dose decitabine, as well as the clinical progress of decitabine in the treatment of hematologic malignancies. Published manuscripts in English were selected from PubMed using a combination of the following search terms: acute myeloid leukemia, pharmacokinetics, decitabine, 5-aza-2'-deoxycytidine, DNA methylation, DNA methyltransferase, myelodysplastic syndrome and leukemia.

EXPERT OPINION

Decitabine has established efficacy in MDS and shown promising activity in AML at low doses. Given decitabine’s favorable toxicity profile and emerging clinical efficacy, decitabine may be a low intensity therapeutic option for elderly patients with AML who are considered unfit for aggressive chemotherapy.

Role of rituximab in first-line treatment of chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a biologically heterogeneous illness that primarily afflicts the elderly. For many decades, the initial therapy for most patients requiring treatment was limited to single-agent alkylator therapy. Within the last two decades, we have seen remarkable progress in understanding the biology of CLL and the development of more effective treatment strategies that have employed monoclonal antibodies, such as rituximab (anti-CD20). Furthermore, recognition of the synergy between fludarabine, cyclophosphamide, and rituximab (FCR) prompted investigators to explore the clinical activity of FCR in Phase II and III trials in patients with relapsed/refractory or previously untreated CLL. On the basis of these findings, the US Food and Drug Administration (FDA) recently approved rituximab in combination with fludarabine and cyclophosphamide for the treatment of patients with relapsed/refractory or previously untreated CD20-postive CLL. Recent data from a randomized Phase III trial has confirmed improved overall survival with FCR in patients with previously untreated CLL. However, FCR is not for everyone. More tolerable regimens using rituximab for the elderly and less fit patients are being pursued in clinical trials. Recent Phase II trials have explored potentially less myelosuppressive approaches by using lower doses of fludarabine and cyclophosphamide, replacing fludarabine with pentostatin, and combining rituximab with chlorambucil. Furthermore new biomarkers predictive of early disease progression have prompted investigators to explore the benefits of early treatment with rituximab combined with other agents. In addition to the proven utility of rituximab as a frontline agent for CLL, rituximab has a favorable toxicity profile both as a single agent and in combination with chemotherapy. The majority of adverse events are Grade 1 and 2 infusion-related reactions (fevers, chills, and rigors) and occur with the first dose of rituximab. The improved tolerability observed with second and subsequent infusions allows for shorter infusion times. Rituximab's proven activity and favorable toxicity profile has made it an ideal agent for expanding treatment options for patients with CLL, the majority of whom are elderly.

Current and future management options for myelodysplastic syndromes

The management of the myelodysplastic syndromes (MDS) requires insight into the complex biology of the disease. Despite this challenge, two recent developments have contributed significantly to advancements in the treatment of MDS: (i) improvements in classification systems and prognostic models; and (ii) the emergence of US FDA-approved agents such as lenalidomide, azacitidine and decitabine. Prior to these developments, supportive care measures consisting of blood and platelet transfusions, haematopoietic growth factors and antimicrobials remained standard of care for the treatment of MDS. As a result of these developments, clinicians are able to provide patient-tailored therapy for specific MDS subgroups. Clinical trials addressing combination therapies with multiple investigational agents as well as novel combination regimens are ongoing. This review focuses on supportive care modalities, the approved agents indicated for the treatment of MDS and future directions for the treatment of MDS, including agents under clinical investigation.

Thrombocytopenia in patients with myelodysplastic syndromes

Thrombocytopenia, common in leukemias and myelodysplastic syndromes (MDS), is responsible for increased risk of bleeding and delay of therapy. Platelet transfusions, although effective in increasing platelet counts, are limited by supply, are associated with risks, and result in limited and transient benefits. Successful development of an alternative treatment approach with thrombopoietin agonists was nearly thwarted when early formulations of recombinant thrombopoietin agonists elicited antibodies that cross-reacted with and neutralized endogenous thrombopoietin. The effectiveness of these recombinant agents led to the development of second-generation thrombopoietin receptor agonists that do not induce cross-reacting neutralizing antibodies against thrombopoietin. Two of the novel thrombopoietin receptor agonists, romiplostim and eltrombopag, have established clinical activity in chronic immune (idiopathic) thrombocytopenic purpura (ITP), and are being explored for the treatment of thrombocytopenia in MDS.

EUELC project: a multi-centre, multipurpose study to investigate early stage NSCLC, and to establish a biobank for ongoing collaboration

The European Early Lung Cancer (EUELC) project aims to determine if specific genetic alterations occurring in lung carcinogenesis are detectable in the respiratory epithelium. In order to pursue this objective, nonsmall cell lung cancer (NSCLC) patients with a very high risk of developing progressive lung cancer were recruited from 12 centres in eight European countries: France, Germany, southern Ireland, Italy, the Netherlands, Poland, Spain and the UK. In addition, NSCLC patients were followed up every 6 months for 36 months. A European Bronchial Tissue Bank was set up at the University of Liverpool (Liverpool, UK) to optimise the use of biological specimens. The molecular-pathological investigations were subdivided into specific work packages that were delivered by EUELC Partners. The work packages encompassed mutational analysis, genetic instability, methylation profiling, expression profiling utilising immunohistochemistry and chip-based technologies, as well as in-depth analysis of FHIT and RARbeta genes, the telomerase catalytic subunit hTERT and genotyping of susceptibility genes in specific pathways. The EUELC project engendered a tremendous collaborative effort, and it enabled the EUELC Partners to establish protocols for assessing molecular biomarkers in early lung cancer with the view to using such biomarkers for early diagnosis and as intermediate end-points in future chemopreventive programmes.

The impact of a quadrivalent human papillomavirus (types 6, 11, 16, 18) virus-like particle vaccine in European women aged 16 to 24

BACKGROUND

Quadrivalent human papillomavirus (HPV types 6/11/16/18) L1 VLP vaccine is highly effective in preventing HPV 6/11/16/18-related cervical and external genital disease. Herein, we evaluated the impact of the quadrivalent HPV 6/11/16/18 L1 VLP vaccine on prevention of HPV-associated cervico-genital lesions in a broad population of sexually active European women.

METHODS

Female subjects (N = 9265) aged 16-24 with four or fewer lifetime sexual partners were enrolled and randomized to quadrivalent HPV vaccine or placebo. Subjects underwent cervicovaginal sampling for HPV DNA detection. Papanicolaou testing and anti-HPV 6/11/16/18 serology testing was also performed.

RESULTS

Vaccine efficacy against lesions representing immediate cervical cancer precursors (cervical intraepithelial neoplasia grade 2/3 or adenocarcinoma in situ) related to HPV 6/11/16/18 in the per-protocol population was 100.0%[95% confidence interval (95% CI), 89.8-100.0]. Efficacy against external genital lesions (vulvar or vaginal intraepithelial neoplasia, condyloma, vulvar or vaginal cancer) related to vaccine HPV types in the per-protocol European population was 99.0% (95% CI, 94.4-100.0).

CONCLUSION

These data demonstrate that quadrivalent HPV 6/11/16/18 vaccination programs in 16- to 24-year-old European women can be beneficial. NCT0009252, NCT00092534, NCT00092495.

Insights Into Non-Thermal Recovery of Heavy Oil

Abstract

Many heavy oil reservoirs contain oil that has some limited mobility under reservoir conditions. In these reservoirs, a small fraction of the oil-in-place can be recovered using the internal reservoir energy through heavy oil solution gas drive (primary production). An integral part of this process is the so-called 'foamy oil mechanism', whereby oil is produced as a gas-in-oil dispersion. At the end of primary production, the bulk of the oil is still in place, while the natural energy of the reservoir has been depleted. This remaining oil is still mostly continuous and presents a valuable target for further recovery. Many of these reservoirs are relatively small or thin, or may be contacted by overlying gas or underlying water. As such, they are poor candidates for thermal oil recovery methods, so any additional oil recovery after primary production must be non-thermal. In this work, we present experimental results of foamy oil depletion at two different length scales and varying depletion rates. Tests were conducted in the absence of sand production, and the results from the depletion experiments are interpreted in terms of viscous forces. At the conclusion of primary recovery, the potential for further non-thermal exploitation of these reservoirs is explored. Results for waterflooding and chemical flooding are presented, demonstrating the viability of these techniques for heavy oil EOR. Several displacement mechanisms are identified through the secondary and tertiary processes that contribute to significant (although potentially slow) incremental recovery of heavy oil.

Introduction

Many countries have heavy oil reservoirs. Canada and Venezuela in particular contain some of the largest heavy oil and bitumen resources in the world. Rising energy demands, coupled with a decline in conventional oil reserves, has led to increased interest in heavy oil recovery in recent years. The size of these heavy oil deposits is considerable, and with volatile crude oil prices making it difficult to produce from some higher viscosity bitumen reservoirs, production of heavy oil could potentially be very important in years to come. Understanding the mechanisms by which heavy oil can be displaced in reservoirs is crucial to the successful recovery of this resource base.

Heavy oil can be defined as a class of oils with viscosity ranging from 50 mPa.s up to around 50,000 mPa.s. This oil has limited mobility under reservoir temperature and pressure, and Darcy's Law predicts that the oil can flow slowly under high applied pressure gradients. However, it has been observed that in these reservoirs, solution gas drive leads to significantly higher rates and recoveries than what was expected by conventional understanding of gas-oil relative permeability behaviour(1). This behaviour, first reported in Canadian heavy oil, has since been observed in many other reservoirs around the world including South America, China and Albania. Investigations into the causes of this abnormal, but fortuitous, primary production response have been the focus of many publications in the past 25 years.

The recovery from primary production in heavy oil reservoirs may be as high as 20%(2), but is usually lower.

Potential for Alkali-Surfactant Flooding in Heavy Oil Reservoirs Through Oil-in-Water Emulsification

Abstract

Alkali-surfactant flooding is an established enhanced oil recovery technique in conventional oil reservoirs, whereby the injected chemical lowers the oil/water interfacial tension, leading to reduced trapping of oil ganglia. In the past, there have been some studies of alkali and alkali-surfactant flooding of heavy oil systems as well, and it has been observed that chemical injection can lead to improved oil recovery. The heavy oil recovery mechanism proposed in this work is the creation of oil-in-water emulsions, which may form under conditions of low interfacial tension and shear due to flow through rock pores. Oil may either be produced in the water (emulsification and entrainment) or the droplets may coalesce or plug the rock pores, leading to improved sweep efficiency (emulsification and entrapment). Both of these mechanisms are investigated in laboratory systems of varying rock permeability, using a heavy oil with a viscosity of 11,500 mPa.s. When oil-in-water emulsions form, the oil recovery can be improved significantly, even without the addition of polymer for mobility control. The effect of permeability and varying injection rates are considered, to understand how different ranges of shear affect the efficiency of these emulsion systems.

Introduction

Several countries in the world, notably Canada and Venezuela, contain significant deposits of heavy oil and bitumen. As Canadian conventional oil reserves continue to decline, the industry interest is now shifting rapidly towards the recovery of this unconventional crude. The immensity of this resource base is exciting, but heavy oil reservoirs pose unique challenges when designing recovery strategies.

The Canadian oil sands are unconsolidated, high porosity and high permeability reservoirs. Ease of flow is therefore not an issue, as it is in many conventional oil reservoirs. Rather, the single biggest impediment to the successful recovery of heavy oil and bitumen is the high oil viscosity. Heavy oil reservoirs are a special subset of our oil sands, whereby the oil viscosity at reservoir temperature varies from around 50 mPa.s up to around 50,000 mPa.s. At reservoir conditions, the oil requires high pressure draw downs in order for it to flow even through the permeable sands, after which point the reservoir has been depleted of all of its natural energy. In order to recover additional heavy oil, energy has to be injected into the reservoir. Often, this takes the form of a fluid that displaces the oil, meaning that the oil must be made to flow to production wells. Most improved/enhanced oil recovery schemes focus on reduction of the oil viscosity through the application of heat or miscible solvents. However, many of the Canadian heavy oil reservoirs are relatively small and thin, and have been disturbed to an unknown extent during primary production. Therefore, the development of injection strategies that are not energy intensive (i.e. non-thermal) and easy to control will be of considerable benefit to heavy oil producers.

In this work, alkali-surfactant solution is investigated as a potential non-thermal injection fluid. It is demonstrated that through the injection of low concentrations of alkali and preformed surfactant solution, oil recovery can be increased significantly above that of waterflooding.

Incomplete dissociation of glibenclamide from wild-type and mutant pancreatic K ATP channels limits their recovery from inhibition

BACKGROUND AND PURPOSE

The antidiabetic sulphonylurea, glibenclamide, acts by inhibiting the pancreatic ATP-sensitive K(+) (K(ATP)) channel, a tetradimeric complex of K(IR)6.2 and sulphonylurea receptor 1 (K(IR)6.2/SUR1)(4). At room temperature, recovery of channel activity following washout of glibenclamide is very slow and cannot be measured. This study investigates the relation between the recovery of channel activity from glibenclamide inhibition and the dissociation rate of [(3)H]-glibenclamide from the channel at 37 degrees C.

EXPERIMENTAL APPROACH

K(IR)6.2, K(IR)6.2DeltaN5 or K(IR)6.2DeltaN10 (the latter lacking amino-terminal residues 2-5 or 2-10 respectively) were coexpressed with SUR1 in HEK cells. Dissociation of [(3)H]-glibenclamide from the channel and recovery of channel activity from glibenclamide inhibition were determined at 37 degrees C.

KEY RESULTS

The dissociation kinetics of [(3)H]-glibenclamide from the wild-type channel followed an exponential decay with a dissociation half-time, t(1/2)(D) = 14 min; however, only limited and slow recovery of channel activity was observed. t(1/2)(D) for K(IR)6.2DeltaN5/SUR1 channels was 5.3 min and recovery of channel activity exhibited a sluggish sigmoidal time course with a half-time, t(1/2)(R) = 12 min. t(1/2)(D) for the DeltaN10 channel was 2.3 min; recovery kinetics were again sigmoidal with t(1/2)(R) approximately 4 min.

CONCLUSIONS AND IMPLICATIONS

The dissociation of glibenclamide from the truncated channels is the rate-limiting step of channel recovery. The sigmoidal recovery kinetics are in quantitative agreement with a model where glibenclamide must dissociate from all four (or at least three) sites before the channel reopens. It is argued that these conclusions hold also for the wild-type (pancreatic) K(ATP) channel.

Human papillomavirus 6 seropositivity is associated with risk of head and neck squamous cell carcinoma, independent of tobacco and alcohol use

BACKGROUND

The risk of head and neck squamous cell carcinoma (HNSCC) associated with common human papillomavirus types has not been well defined.

METHODS

We conducted a case-control study of 1034 individuals (486 incident cases diagnosed with HNSCC and 548 population-based controls matched to cases by age, gender, and town of residence) in Greater Boston, MA. Sera were tested for antibodies to human papillomavirus (HPV)6, HPV11, HPV16, and HPV18 L1.

RESULTS

HPV6 antibodies were associated with an increased risk of pharyngeal cancer [odds ratio (OR)=1.6, 1.0-2.5], controlling for smoking, drinking, and HPV16 seropositivity. In HPV16-seronegative subjects, high HPV6 titer was associated with an increased risk of pharyngeal cancer (OR=2.3, 1.1-4.8) and oral cancer (OR=1.9, 1.0-3.6), suggesting that the cancer risk associated with HPV6 is independent of HPV16. There was no association between smoking and alcohol use and HPV6 serostatus. Further, the risk of pharyngeal cancer associated with heavy smoking was different among HPV6-seronegative (OR 3.1, 2.0-4.8) and HPV6-seropositive subjects (OR=1.6, 0.7-3.5), while heavy drinking also appears to confer differing risk among HPV6-negative (OR 2.3, 1.5-3.7) and -positive subjects (OR=1.3, 0.6-2.9).

CONCLUSIONS

There may be interactions between positive serology and drinking and smoking, suggesting that the pathogenesis of human papillomavirus in HNSCC involves complex interactions with tobacco and alcohol exposure.

An investigation of the effects of saccharides on the memory performance of middle-aged adults

OBJECTIVES

To investigate the effects of glucose, or a combination of saccharides, or a placebo on the memory performance of middle-aged adults.

DESIGN

A double-blind, placebo controlled design was used. A population-based sample of 45 men and women (aged 40-63 years) completed a series of memory tasks following administration of a single dose of either glucose, a combination of saccharides or placebo. Memory tasks included immediate and delayed recall, recognition, short-term memory, working memory, and a test of general cognitive ability.

RESULTS

There were no statistically significant effects of treatments on any of the outcome measures.

CONCLUSION

The pattern of means in the combination of saccharides group suggests potential enhancement effects of memory performance in middle-aged adults that deserves further investigation.

Medical civil-military operations: the deployed medical brigade's role in counterinsurgency operations

Medical civil-military operations are a critical combat multiplier directly supporting the counterinsurgency fight. Army Medical Department Soldiers support medical civil affairs activities at all levels from platoon to the United States Mission-Iraq (Department of State) initiatives enhancing the legitimacy of medical services in the Iraq Ministry of Health, Ministry of Defense, Ministry of the Interior, and Ministry of Justice. The civil-military operations mission of the deployed Task Force 62 Medical Brigade has also evolved into a broad mission encompassing over 120 contractors including Iraqi-American, Bilingual Bicultural Advisors-Subject Matter Experts serving as case management liaison officers and medical trainers, as well as Iraqi Advisor Task Force members providing medical atmospherics, assessments, training, and the overall management of Iraqi linguists supporting all level III medical facilities.

Cognitive effects of polyunsaturated fatty acids in children with attention deficit hyperactivity disorder symptoms: a randomised controlled trial

This study investigated effects of PUFA and micronutrient supplementation on cognition in children with ADHD symptoms. In a randomised controlled trial, 7-12-year-old children with symptoms 2 S.D. on Conners' ADHD Index were given PUFA, PUFA+multivitamins/minerals (MVM), or placebo for 15 weeks, and then all children were given PUFA+MVM for an additional 15 weeks. After 15 weeks there were improvements in a test of the ability to switch and control attention (Creature Counting) in the PUFA groups compared to placebo (N=129, p=0.002). This improvement was also observed in the placebo group after taking PUFA from weeks 16 to 30 (N=104). There were no significant improvements in other cognitive measures, or with additional micronutrient supplementation. However, improvements in cognitive performance mediated previous parent-reported improvements in inattention, hyperactivity and impulsivity [N. Sinn, J. Bryan, Effect of supplementation with polyunsaturated fatty acids and micronutrients on ADHD-related problems with attention and behaviour, J. Dev. Behav. Pediatr. 28 (2) (2007) 82-91], suggestive of a common neurological mechanism for these symptoms.