Impact of radiation therapy on healthy and cancerous cell dynamics: a Mathematical analysis

This study proposes a novel therapeutic model for cancer treatment with radiation therapy by analyzing the interactions among cancer, immune and healthy cells through a system of three ordinary differential equations. In this model, the natural influx rate of mature immune cells is assumed constant and is denoted by, a. The overall effect of radiation therapy on cancer cells is represented by a parameter, s; which is the surviving fraction of cells as determined by the Linear Quadratic (LQ) model. Conditions for the stability of equilibria in the interaction model modified to include the surviving fraction, are systematically established in terms of the dose and model parameters. Numerical simulations are performed in Wolfram MATHEMATICA software, investigating a spectrum of initial cell population values irradiated with 60Co γ -ray Low-LET radiation and High-LET 165 keV / μ m Ni-ion radiation to facilitate improved visualization and in-depth analysis. By analyzing the model, this study identifies threshold values for the absorbed dose D for particular values of the model and radiation parameters for both High Linear Energy Transfer (high-LET) and Low Linear Energy Transfer (low-LET) radiations that ensure either eradication or minimization of cancer cells from a patient's body, providing valuable insights for designing effective cancer treatments.

A two-galectin network establishes mesenchymal condensation phenotype in limb development

Previous work showed that Gal-1A and Gal-8, two proteins belonging to the galactoside-binding galectin family, are the earliest determinants of the patterning of the skeletal elements of embryonic chicken limbs, and further, that their experimentally determined interactions in the embryonic limb bud can be interpreted via a reaction-diffusion-adhesion (2GL: two galectin plus ligands) model. Here, we use an ordinary differential equation-based approach to analyze the intrinsic switching modality of the 2GL network and characterize the network behavior independent of the diffusive and adhesive arms of the patterning mechanism. We identify two states: where the concentrations of both the galectins are respectively, negligible, and very high. This bistable switch-like system arises via a saddle-node bifurcation from a monostable state. For the case of mass-action production terms, we provide an explicit Lyapunov function for the system, which shows that it has no periodic solutions. Our model therefore predicts that the galectin network may exist in low expression and high expression states separated in space or time, without any intermediate states. We test these predictions in experiments performed with high density cultures of chick limb mesenchymal cells and observe that cells inside precartilage protocondensations express Gal-1A at a much higher rate than those outside, for which it was negligible. The Gal-1A and -8-based patterning network is therefore sufficient to partition the mesenchymal cell population into two discrete cell states with different developmental (chondrogenic vs. non-chondrogenic) fates. When incorporated into an adhesion and diffusion-enabled framework this system can generate a spatially patterned limb skeleton.

Improving maternal update rates within the first hour of NICU admission

BACKGROUND

Timely communication is essential in attaining maternal satisfaction, developing an excellent physician-patient rapport, and increasing trust. This study reports a significant improvement in maternal communication rates through the quality improvement method.

METHODS

An educational module was developed, and NICU staff was presented with the slides, followed by a performance questionnaire to demonstrate understanding. The first phase was completed by obtaining feedback from mothers through a questionnaire. The first plan-do-study-act (PDSA) cycle, carried out for eight weeks looking at the rates of the maternal update provided within an hour of admission of their neonates to the NICU, was followed by the second PDSA cycle, carried out for ten weeks. The improvement was calculated using conventional statistics and a statistical process control chart.

RESULTS

During the first phase of the study, thirty-six percent of the mothers were updated within an hour of admission of their neonates to the NICU. During the first PDSA cycle, we did not notice a special cause variation or process change. A significant shift, eight consecutive points above the mean, was noted on the control chart during PDSA cycle 2. The mean±SD of the weekly update rate increased significantly during PDSA cycle 2 (76.8±11) compared to PDSA cycle 1 (47.5±14), p-value = 0.0002.

CONCLUSION

We improved the maternal update rates through the educational module following the QI improvement model using the PDSA cycles.

TB disease patterns by HIV and diabetes status

BACKGROUND: TB is commonly categorised as pulmonary (PTB) or extrapulmonary TB (EPTB). Knowledge of TB disease patterns (PTB and/or EPTB) and determining risk factors remains limited.METHODS: This was a prospective cohort study using point-of-care ultrasound (POCUS) in Indian patients with presumed TB. Clinical and imaging data were used to develop refined case definitions for PTB, concurrent PTB and EPTB (PTB + EPTB) and EPTB without PTB (EPTB). These groups were analysed by HIV (HIV+/-) and diabetes mellitus (DM+/-) status.RESULTS: Of 172 HIV-/DM- patients with TB, 48% had PTB, 23% PTB + EPTB and 29% had EPTB, totalling 52% with any EPTB (PTB + EPTB or EPTB). In HIV+/DM- patients with TB (n = 35), 6% had PTB, 40% had PTB + EPTB and 54% had EPTB, accounting for 94% with EPTB. In HIV-/DM+ patients with TB (n = 61), 61% had PTB, 28% had PTB + EPTB and 11% had EPTB, representing 39% with EPTB.CONCLUSION: Refined case definitions revealed high proportions of EPTB even without HIV or DM. HIV further altered the TB disease pattern towards EPTB and DM towards PTB. Therefore, the dichotomy between PTB or EPTB does not represent the actual spectrum of TB disease. EPTB should receive higher priority in research and clinical practice.

ONCOLYTIC ACTIVITY OF HUMAN ORTHOPNEUMOVIRUS IN CANCER CELL LINES

Oncolytic virotherapy is an emerging biotherapeutic platform for selectively infecting cancer cells and triggering apoptosis in a number of malignant cells due to robust viral replication. Studies related to the oncolytic activity of human orthopneumovirus (hOPV) are conflicting.

AIM

This study was designed to elucidate the possible role of hOPV in the modulation of cell growth and apoptosis in cancer cell lines including human epidermoid carcinoma (HEp-2), lung epithelial cell line (A549), and breast cancer cell line (MCF-7).

MATERIALS AND METHODS

The oncolytic activity of hOPV on cancer cells was studied in vitro. The virus titers were determined by tissue culture infectious dose (TCID50/mL) in A549 cell. The cytotoxic effect of the virus on HEp-2, A549, and MCF-7 was determined using MTT and trypan blue dye exclusion test assays. hOPV in the infected cells was detected using real-time reverse transcription polymerase chain reaction (rRT-PCR) and indirect immunofluorescence (IIF) assays. The relative expression of apoptosis-related genes (CASP-3, -8, -9, Bax, Bcl-2, Bcl-XL, TP53, P21) during virus infection was estimated using rRT-PCR assay in comparison with the house-keeping gene (GAPDH).

RESULTS

hOPV infection inhibited the growth of HEp-2, A549, and MCF-7 cells in a dose-and time-dependent manner. At a multiplicity of infection (MOI) of 5, hOPV reduced the viability of A549 cells to about 16%, HEp-2 to 22%, and MCF-7 to 28% (p = 0.001), while no significant inhibitory effect was observed when cells were infected at MOI of 1 and 2. hOPV mRNA and antigens were detected in infected HEp-2, A549, and MCF-7 cells by RT-PCR and IIF. Upon hOPV infection, expression of CASP-3, -8, -9, as well as Bax, TP53, and p21 mRNA increased while expression of Bcl-2, Bcl-xL anti-apoptotic genes decreased. In hOPV-infected A549 cells, the fold increase of CASP-8 and CASP-9, Bax, TP53, and P21 expression exceeded significantly compared to that in HEp-2 or MCF-7 cells.

CONCLUSIONS

Our results provide evidence that hOPV could be a potential candidate for oncolytic virotherapy.

Durability of SARS-CoV-2 Specific IgG Antibody Responses Following Two Doses of Match and Mixed COVID-19 Vaccines Regimens in Saudi Population

Background

SARS-CoV-2 pandemic continues to threaten the human population with millions of infections and deaths worldwide. Vaccination campaigns undertaken by several countries have resulted in a notable decrease in hospitalization and deaths. However, with the emergence of new virus variants, it is critical to determine the longevity and the protection efficiency provided by the current authorized vaccines.

Aim

The aims of this study are to provide data about the magnitude of immune responses in individuals fully vaccinated against COVID-19 in Riyadh province of Saudi Arabia. Also, to evaluate the continuity of specific IgG levels and compare the titers in individuals who have been received two doses of the matched and mixed vaccines, including Pfizer and AstraZeneca against SARS-CoV-2 during the period of three to six months. Moreover, we analyze the current state of immune response in terms of antibody responses in thepopulation postvaccination using homogenous or hetrogenous vaccine regimen.

Methods

A total of 141 healthy volunteers were recruited to our study; blood (n=63) and the saliva samples (n=78) and were collected from fully vaccinated individuals in Riyadh city. We employed a specific ELISA assay in plasma and saliva of fully vaccinated individuals.

Results

IgG levels varied with age groups with the highest concentration in the age group 19–29 years, but the age group (≥50) had the lowest IgG concentration. The IgG levels in both serum and saliva were higher after three months and start to wane after six months. Individuals who received mixed types of vaccines had significantly better response than Pfizer vaccine alone.

Conclusion

The current study investigates the status of humoral responses in different age groups, in terms of antibody measurements. These data will help to evaluate the need for further COVID-19 vaccine doses and to what extent a two-dose regimen will protect vaccinated individuals.

Online KidClot education for patients and families initiating warfarin therapy: The eKITE study

Anticoagulation with Vitamin K antagonists (VKA) has always posed challenges in terms of monitoring requirements. These challenges were further exacerbated in the setting of the COVID-19 pandemic, with limited access to and/or avoidance of laboratory testing. The importance of utilizing point of care (POC) health technology for individualized patient management is salient. The foundation of effective home INR monitoring is establishing patient knowledge about their therapy and INR testing proficiency. The eKITE series was developed to support patients in establishing foundational knowledge required for VKA (warfarin) management and INR monitoring. The primary objectives were to evaluate eKITE, a patient-oriented innovative online education program for warfarin therapy, participant learning stress, and patient preference for online learning. This multi-center prospective study provided patients access to warfarin online education. Participants were required to complete written quizzes assessing warfarin knowledge of key concepts proficiency and identifying knowledge deficits. Patient preference, evaluating calm (lack of anxiety) while learning, and an INR on a home meter was completed. Participants performed INR tests at home and reported INRs by telephone. The analysis included 144 children and caregivers enrolled at five US and CDN sites. Most indications for anticoagulation were cardiac (congenital or acquired heart disease) with varied INR target ranges. Mean knowledge scores for warfarin and INR self-testing modules were 97%, with low anxiety with TTR of 84%. Patient preferred online learning. eKITE is an effective teaching modality for warfarin/home INR monitoring with safe INR testing and warfarin management that is appropriate for pediatrics and adults alike. PROLOGUE: The whir in the hallways is deafening. Lights bright, alarms are ringing in a chorus of unsynchronized beeps and screeches. It has been more than a week since I have slept. Snuggled beside me is my precious child, whining and equally irritated with the asynchronous symphony, further compounded by anxiety, procedures, and pain. The sun has broken. The staff smiles are welcoming and incessant, as one after one, they approach hurried, urgent, assiduous, their need to coach me for our upcoming departure to the warmth of home. Each provides essential information that I will require to keep my child, my treasure, safe and healthy. Yet, my eyes are heavy, blurred, and my brain foggy, trapped in a dark heavy cloud. How am I to follow? Comprehend? and retain anything? As they instruct, my precious child yearns for loving arms, compassion and love, whining, crying in disquiet. Overwhelmed does not adequately describe my ineffable exhaustion. Amidst this, how am I to learn about warfarin? Such a challenging medication, with so much to know. Concentrate, I tell myself, focus; now is my only opportunity to learn. I must be alert. It seems to be nonsensical.

COVID-19 Pandemic: Outbreak, Potential Vaccines And Medications

The outbreak of the current global pandemic caused by the spread of a novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has posed an unprecedented threat to global health and economy across the whole world. As of today, the number of cases diagnosed with SARS-CoV-2 is exceeding 271 million with over 5.32 million deaths globally. Despite the high throughput technology and considerable advances in sciences, the outbreaks of the COVID-19 pandemic present a colossal challenge to scientific community. Scientists and clinicians all over the world are putting tremendous efforts to develop effective treatments to combat this deadly pathogen, at least to contain it momentarily until an adequate treatment regimen is available. Conventionally, vaccines have been developed as one of the therapeutic strategies to restrict infectious diseases. Although several vaccines are in the pipeline, evaluation of efficacy in animals’ studies and human are time-consuming. On the other hand, several drugs already in clinical use are being employed to test their efficacy against SARS-CoV-2. Some of these drugs have been already used as anti-viral drugs and others have been used for different therapeutic purposes. In this review, we summarize the ongoing efforts to control the dissemination of SARS-CoV-2 and highlight the potential prophylactic and therapeutic measures including the recently developed vaccines in the foreseeable future. Moreover, we emphasize an importance of having a customized strategy that can be easily and quickly employed to overcome possible future outbreaks.

Steroids use in non-oxygen requiring COVID-19 patients: a systematic review and meta-analysis

BACKGROUND

Corticosteroids have become the mainstay treatment in severe COVID-19. However, its role is mild disease is controversial due to lack of robust scientific evidence. This systematic review and meta-analysis were conducted to assess effect of steroids in mild COVID-19 patients.

METHODS

PubMed, EMBASE, Web of Science and medRxiv were searched from 31 December 2019 to 14 May 2021 for studies that reported effectiveness of steroids in non-oxygen requiring COVID-19 patients in terms of progressing to severe disease, mortality, duration of fever, duration of viral clearance and length of hospital stay (LOHS). Studies on inhalational steroids, case reports and reviews were excluded. Risk of bias (ROB) was assessed by the Cochrane's ROB tool and ROBANS tool. Quantitative data synthesis was done using the generic inverse variance method.

RESULTS

A total of 6411 studies were identified, 2990 articles were screened after exclusion. Seven studies which fit the criteria (involving 2214 non-oxygen requiring COVID-19 patients) were included and analysed. Overall odds of progression to severe disease among the non-oxygen requiring COVID-19 patients receiving steroids was 5.97 [95% confidence interval (CI): 1.27-27.99, I2 = 0%] and odds of death (OR: 1.35, 95% CI: 1.01-1.79; I2 = 0%) as compared to the patients not receiving steroids. Mean duration of fever (7.4 days), duration to viral clearance (18.9 days) and LOHS (20.8 days) were significantly higher in the steroid arm, as compared to that in no-steroid arm (6.7, 16.5 and 15.2 days, respectively).

CONCLUSION

Steroids in non-oxygen requiring COVID-19 patients can be more detrimental than beneficial.

PROTOCOL REGISTRATION

The study was prospectively registered in PROSPERO (CRD 42021254951).

COVID-19-associated mucormycosis presenting to the Emergency Department-an observational study of 70 patients

BACKGROUND

Mucormycosis (MM) is a deadly opportunistic fungal infection and a large surge in COVID-19-associated mucormycosis (CAM) is occurring in India.

AIM

Our aim was to delineate the clinico-epidemiological profile and identify risk factors of CAM patients presenting to the Emergency Department (ED).

DESIGN

This was a retrospective, single-centre, observational study.

METHODS

We included patients who presented with clinical features or diagnosed MM and who were previously treated for COVID-19 in last 3 months of presentation (recent COVID-19) or currently being treated for COVID-19 (active COVID-19). Information regarding clinical features of CAM, possible risk factors, examination findings, diagnostic workup including imaging and treatment details were collected.

RESULTS

Seventy CAM patients (median age: 44.5 years, 60% males) with active (75.7%) or recent COVID-19 (24.3%) who presented to the ED in between 6 May 2021 and 1 June 2021, were included. A median duration of 20 days (interquartile range: 13.5-25) was present between the onset of COVID-19 symptoms and the onset of CAM symptoms. Ninety-three percent patients had at least one risk factor. Most common risk factors were diabetes mellitus (70%) and steroid use for COVID-19 disease (70%). After clinical, microbiological and radiological workup, final diagnosis of rhino-orbital CAM was made in most patients (68.6%). Systemic antifungals were started in the ED and urgent surgical debridement was planned.

CONCLUSION

COVID-19 infection along with its medical management have increased patient susceptibility to MM.

SARS-CoV-2: An Overview of Virus Genetics, Transmission, and Immunopathogenesis

The human population is currently facing the third and possibly the worst pandemic caused by human coronaviruses (CoVs). The virus was first reported in Wuhan, China, on 31 December 2019 and spread within a short time to almost all countries of the world. Genome analysis of the early virus isolates has revealed high similarity with SARS-CoV and hence the new virus was officially named SARS-CoV-2. Since CoVs have the largest genome among all RNA viruses, they can adapt to many point mutation and recombination events; particularly in the spike gene, which enable these viruses to rapidly change and evolve in nature. CoVs are known to cross the species boundaries by using different cellular receptors. Both animal reservoir and intermediate host for SARS-CoV-2 are still unresolved and necessitate further investigation. In the current review, different aspects of SARS-CoV-2 biology and pathogenicity are discussed, including virus genetics and evolution, spike protein and its role in evolution and adaptation to novel hosts, and virus transmission and persistence in nature. In addition, the immune response developed during SARS-CoV-2 infection is demonstrated with special reference to the interplay between immune cells and their role in disease progression. We believe that the SARS-CoV-2 outbreak will not be the last and spillover of CoVs from bats will continue. Therefore, establishing intervention approaches to reduce the likelihood of future CoVs spillover from natural reservoirs is a priority.

Mid-term follow-up of percutaneous access for standard and complex EVAR using the ProGlide device

OBJECTIVES

Endovascular Aneurysm Repair is an established treatment for abdominal aortic aneurysm which requires arterial access via the groin. Most centres perform percutaneous ultrasound-guided access into the common femoral artery for delivery of the stent graft. The profile of endovascular devices necessitates large sheath sizes, therefore formal closure of the arterial puncture site is required. Various percutaneous devices are available, with data lacking on efficacy and mid-term safety profile. We present outcomes from a single centre with the Perclose ProGlide™ (Abbott Vascular Devices, CA, USA) suture-mediated system, using the well described "pre-close" technique.

MATERIALS & METHODS

Data were collected from operative records and electronic medical records. Patients undergoing standard (EVAR) or complex (F/B-EVAR) aneurysm repair between March 2015 and September 2019 were included. Complications were recorded per-patient and per-groin procedure.

RESULTS

266 patients were included; 182 (68.4%) standard infrarenal EVAR, 84 (31.6%) F/B-EVAR. There were a total of 484 groin procedures performed. Intraoperative Perclose ProGlide™ success was 98.1% (per patient) or 99.0% (per groin procedure). 30-day groin complication rate was 6.1% (per patient) or 3.1% (per groin procedure). There were no pre- or peri-operative factors which predicted the occurrence of groin complications. The rate of groin complications was not related to sheath size.

CONCLUSIONS

Our data support the use of percutaneous access with a pre-close technique for a variety of endovascular aneurysm repair procedures with both large- and small-bore access. The Perclose ProGlide™ system provides excellent mid-term complication-free and reintervention-free outcomes for groin procedures.

Matrix adhesion and remodeling diversifies modes of cancer invasion across spatial scales

The metastasis of malignant epithelial tumors begins with the egress of transformed cells from the confines of their basement membrane (BM) to their surrounding collagen-rich stroma. Invasion can be morphologically diverse: when breast cancer cells are separately cultured within BM-like matrix, collagen I (Coll I), or a combination of both, they exhibit collective-, dispersed mesenchymal-, and a mixed collective-dispersed (multimodal)- invasion, respectively. In this paper, we asked how distinct these invasive modes are with respect to the cellular and microenvironmental cues that drive them. A rigorous computational exploration of invasion was performed within an experimentally motivated Cellular Potts-based modeling environment. The model comprised of adhesive interactions between cancer cells, BM- and Coll I-like extracellular matrix (ECM), and reaction-diffusion-based remodeling of ECM. The model outputs were parameters cognate to dispersed- and collective- invasion. A clustering analysis of the output distribution curated through a careful examination of subsumed phenotypes suggested at least four distinct invasive states: dispersed, papillary-collective, bulk-collective, and multimodal, in addition to an indolent/non-invasive state. Mapping input values to specific output clusters suggested that each of these invasive states are specified by distinct input signatures of proliferation, adhesion and ECM remodeling. In addition, specific input perturbations allowed transitions between the clusters and revealed the variation in the robustness between the invasive states. Our systems-level approach proffers quantitative insights into how the diversity in ECM microenvironments may steer invasion into diverse phenotypic modes during early dissemination of breast cancer and contributes to tumor heterogeneity.

Sequence and phylogentic analysis of MERS-CoV in Saudi Arabia, 2012-2019

BACKGROUND

The Middle East Respiratory Syndrome-related Coronavirus (MERS-CoV) continues to exist in the Middle East sporadically. Thorough investigations of the evolution of human coronaviruses (HCoVs) are urgently required. In the current study, we studied amplified fragments of ORF1a/b, Spike (S) gene, ORF3/4a, and ORF4b of four human MERS-CoV strains for tracking the evolution of MERS-CoV over time.

METHODS

RNA isolated from nasopharyngeal aspirate, sputum, and tracheal swabs/aspirates from hospitalized patients with suspected MERS-CoV infection were analyzed for amplification of nine variable genomic fragments. Sequence comparisons were done using different bioinformatics tools available.

RESULTS

Several mutations were identified in ORF1a/b, ORF3/4a and ORF4b, with the highest mutation rates in the S gene. Five codons; 4 in ORF1a and 1 in the S gene, were found to be under selective pressure. Characteristic amino acid changes, potentially hosted and year specific were defined across the S protein and in the receptor-binding domain Phylogenetic analysis using S gene sequence revealed clustering of MERS-CoV strains into three main clades, A, B and C with subdivision of with clade B into B1 to B4.

CONCLUSIONS

In conclusion, MERS-CoV appears to continuously evolve. It is recommended that the molecular and pathobiological characteristics of future MERS-CoV strains should be analyzed on regular basis to prevent potential future outbreaks at early phases.

Induction of Immune Responses and Immune Evasion by Human Bocavirus

Respiratory tract infections are the primary cause of morbidity and mortality globally. Human bocavirus 1 (HBoV1), a member of the Parvoviridae family causes a wide spectrum of respiratory diseases in children, and gastroenteritis in adults. The mechanisms of latency, persistence, and reinfection of Bocavirus are poorly understood at present due to the lack of permissive cell lines and efficient animal models. Moreover, the dual infections of HBoV and other respiratory viruses further complicate the study of the pathogenicity of Bocaviruses. The data on immunological consequences of Bocavirus infection are sparse. However, the existing data have highlighted the role of CD4 T cells in Bocavirus infection. High titres of HBoV-specific antibodies have been detected in different populations suggesting its ubiquitous prevalence. Interestingly, the mechanism employed by Bocavirus to evade the immune system mostly targets type I IFN pathways and cause pyroptotic cell death of host cells. This review summarizes the immune responses evoked in response to Bocavirus infection, escape mechanism employed by the virus, and the vaccination strategies, including antisense technology to combat Bocavirus infections.

Double-edged role of natural killer cells during RSV infection

Natural killer cells play a vital role in the rejection of tumors and pathogen-infected cells. NK cells are indispensable in the early immune response against viral infections by directly targeting infected cells. Furthermore, NK cells influence adaptive immunity by driving virus-specific T-cell responses. Respiratory syncytial virus, a highly contagious virus that causes bronchiolitis, is the main reason for mortality in infants and elderly patients. RSV infection triggers both innate and adaptive immune responses. However, immunity against RSV is ephemeral due to the impaired development of immunological memory. The role of NK cells during RSV infection remains ambiguous. NK cells play a dual role in RSV infection; initially, their role is a protective one as they utilize their intrinsic cytotoxicity, followed by a detrimental one that induces lung injury due to the inhibition of antibody responses and the secretion of pro-inflammatory factors. Noteworthy, IFN-γ released from NK cells play a critical role in promoting a shift to adaptive responses and inhibiting antibody responses in neonates. Indeed, NK cells have a pro-inflammatory and inhibitory role rather than a cytotoxic one that contributes to the severity of the disease. Therapeutic options, including DNA-protein-based vaccines, synthetic peptides, and attenuated strains, are presently under tests. However, there is a need for effective strategies to augment NK cell activity and circumvent the pro-inflammatory activity to benefit the host. In this review, we focused on the role played by NK cells in the immune response and its outcome on the immunopathogenesis of RSV disease.

Peri-operative management of percutaneous fetoscopic spina-bifida repair: a descriptive review of five cases from the United Kingdom, with focus on anaesthetic implications

We present a case-based review of the first five percutaneous fetoscopic in-utero spina bifida repair procedures undertaken in the UK. Our focus is on implications of anaesthesia and analgesia for the mother and fetus, provision of uterine relaxation and fetal immobilisation while providing conditions conducive to surgical access. Minimising risks for fetal acidosis, placental and fetal hypoperfusion, maternal and fetal sepsis and maternal fluid overload were the foremost priorities. We discuss optimisation strategies undertaken to ensure fetal and maternal well-being under anaesthesia, shortcomings in the current approach, and possible directions for improvement.

IMRiS phase II study of IMRT in limb sarcomas: Results of the pre-trial QA facility questionnaire and workshop

INTRODUCTION

Soft tissue sarcomas of the extremities (STSE) are rare malignancies. We report current UK practice for immobilisation of soft tissue sarcoma of STSE, as part of the initial study set-up within the IMRiS trial, a phase II study of intensity modulated radiotherapy (IMRT) in primary bone and soft tissue sarcoma.

METHODS

A facility questionnaire (FQ) was circulated to 29 IMRiS centres investigating the variation in immobilisation devices, planning techniques, and imaging protocols. A workshop was held to address concerns raised by centres. It focused on STSE immobilisation and patient set-up. Robustness of patient set-up at each centre was evaluated based on the following criteria: evidence of local set-up audit, calculation of margins based on set-up audit results, imaging frequency, and number of patients treated per centre per annum.

RESULTS

Twenty-seven (93%) questionnaires were returned. 30% (8/27) of responders routinely treated STSE with IMRT. The remaining 70% (19/27) had little or no experience with IMRT for STSE. Vacuum bags were the most frequent immobilisation device (9/27), followed by thermoplastic shells (7/27). Nine centres had audited their local set-up; however, only 4 had calculated margins in response to the results. Ten centres were classified as having high level of robustness.

CONCLUSIONS

Immobilisation devices and planning techniques for STSE are inconsistent across centres. Robustness of set-up is an important tool to ensure quality of results in a multicentre trial setting with such different levels of experience. The IMRiS trial Quality Assurance programme encourages centres to assess robustness of set-up through local audit and subsequent calculation of treatment margins.

IMPLICATIONS FOR PRACTICE

This is the first study that used robustness criteria to tailor QA support to individual centres.

Abstract P6-20-10: Role of GPR110 in breast cancer

Our long-term goal is to discover adhesion GPCR targets in breast cancer. Our previous studies have found GPR110 to be overexpressed in tumorigenic cell population as well as in anti-HER2 drug-resistant derivatives of HER2+ breast cancer cells. In subsequent studies, we found that GPR110 knockdown inhibited anchorage-independent cell growth, mammosphere formation, and invasion/migration of HER2+ breast cancer cells. Conversely, overexpression of GPR110 by lentiviral delivery of cDNA enhanced anchorage-independent cell growth, mammosphere formation, and invasion/migration in HER2+ breast cancer cells. In addition, GPR110 overexpression led to increase in the % of Aldefluor-positive tumorigenic cell population, further emphasizing the role of GPR110 as a mediator of tumorigenesis in addition to the metastatic processes in HER2+ breast cancer. Among various subtypes of breast cancer, GPR110 expression was higher in HER2+ and basal subtypes, most of which are triple-negative (negative for ER, PR, and HER2), compared to luminal A and B subtypes. GPR110 was either gene amplified or upregulated in 4% of all breast cancers based on the publicly available TCGA dataset. GPR110 overexpression predicted poorer recurrence-free survival in triple-negative breast cancer. Furthermore, GPR110 was overexpressed in brain metastatic lesions compared to mammary tumors in patient-derived xenograft models of triple-negative breast cancer (WHIM2 and WHIM30). Knocking down GPR110 reduced anchorage-dependent and -independent cell growth, mammosphere formation, and invasion/migration of triple-negative breast cancer cells. Overall, our results suggest that GPR110 may be a potential drug target in HER2+ and triple-negative breast cancer. Drug discovery efforts to identify GPR110 antagonists will provide useful pharmacological tools for validating GPR110 as a drug target in breast cancer. Since GPR110 is also overexpressed in various other types of cancer, understanding the mechanism of GPR110 upregulation and signaling in cancer is an important future direction.

This work was supported by the Department of Defense Grants W81XWH-14-1-0340 and W81XWH-14-1-0341 to Drs. Trivedi and Schiff, respectively.

Citation Format: Bhat R, Qin L, De Angelis C, Sahay D, Bhargava D, Creighton C, Yadav P, Yazdanfard S, Alrawi A, Yadav V, Vasaikar S, Nanda S, Sethunath V, Fu X, Zhang B, Narkar V, Schiff R, Trivedi M. Role of GPR110 in breast cancer [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 P6-20-10.

Stent Graft Exclusion of Pseudo-Aneurysm Arising from PTFE Hemodialysis Graft after Recurrence following Ultrasound Guided Thrombin Injection

There are various non-invasive or minimally invasive techniques for management of pseudoaneurysms including ultrasound guided compression, ultrasound guided thrombin injection and covered stent placement. We report a case where a covered stent graft was successfully used for the treatment of a pseudoaneurysm directly arising from a PTFE graft which recurred 3 months following treatment with ultrasound guided thrombin injection.

Lectin-gated and glycan functionalized mesoporous silica nanocontainers for targeting cancer cells overexpressing Lewis X antigen

Gated mesoporous silica nanoparticles can deliver payload upon the application of a predefined stimulus, and therefore are promising drug delivery systems. Despite their important role, relatively low emphasis has been placed on the design of gating systems that actively target carbohydrate tumor cell membrane receptors. We describe herein a new Lewis X (Le^x) antigen-targeted delivery system comprising mesoporous silica nanoparticles (MSNs) loaded with ATTO 430LS dye, functionalized with a Le^x derivative (1) and capped with a fucose-specific carbohydrate-binding protein (Aleuria aurantia lectin (AAL)). This design takes advantage of the affinity of AAL for Le^x overexpressed receptors in certain cancer cells. In the proximity of the cells, AAL is detached from MSNs to bind Le^x, and selectins in the cells bind Le^x in the gated MSNs, thereby inducing cargo delivery. Gated MSNs are nontoxic to colon cancer DLD-1 cells, and ATTO 430LS dye delivered correlated with the amount of Le^x antigen overexpressed at the DLD-1 cell surface. This is one of the few examples of MSNs using biologically relevant glycans for both capping (via interaction with AAL) and targeting (via interaction with overexpressed Le^x at the cell membrane).

Oncolytic H-1 Parvovirus Shows Safety and Signs of Immunogenic Activity in a First Phase I/IIa Glioblastoma Trial

Oncolytic virotherapy may be a means of improving the dismal prognosis of malignant brain tumors. The rat H-1 parvovirus (H-1PV) suppresses tumors in preclinical glioma models, through both direct oncolysis and stimulation of anticancer immune responses. This was the basis of ParvOryx01, the first phase I/IIa clinical trial of an oncolytic parvovirus in recurrent glioblastoma patients. H-1PV (escalating dose) was administered via intratumoral or intravenous injection. Tumors were resected 9 days after treatment, and virus was re-administered around the resection cavity. Primary endpoints were safety and tolerability, virus distribution, and maximum tolerated dose (MTD). Progression-free and overall survival and levels of viral and immunological markers in the tumor and peripheral blood were also investigated. H-1PV treatment was safe and well tolerated, and no MTD was reached. The virus could cross the blood-brain/tumor barrier and spread widely through the tumor. It showed favorable pharmacokinetics, induced antibody formation in a dose-dependent manner, and triggered specific T cell responses. Markers of virus replication, microglia/macrophage activation, and cytotoxic T cell infiltration were detected in infected tumors, suggesting that H-1PV may trigger an immunogenic stimulus. Median survival was extended in comparison with recent meta-analyses. Altogether, ParvOryx01 results provide an impetus for further H-1PV clinical development.

Data-Driven Discovery of Extravasation Pathway in Circulating Tumor Cells

Circulating tumor cells (CTCs) play a crucial role in cancer dissemination and provide a promising source of blood-based markers. Understanding the spectrum of transcriptional profiles of CTCs and their corresponding regulatory mechanisms will allow for a more robust analysis of CTC phenotypes. The current challenge in CTC research is the acquisition of useful clinical information from the multitude of high-throughput studies. To gain a deeper understanding of CTC heterogeneity and identify genes, pathways and processes that are consistently affected across tumors, we mined the literature for gene expression profiles in CTCs. Through in silico analysis and the integration of CTC-specific genes, we found highly significant biological mechanisms and regulatory processes acting in CTCs across various cancers, with a particular enrichment of the leukocyte extravasation pathway. This pathway appears to play a pivotal role in the migration of CTCs to distant metastatic sites. We find that CTCs from multiple cancers express both epithelial and mesenchymal markers in varying amounts, which is suggestive of dynamic and hybrid states along the epithelial-mesenchymal transition (EMT) spectrum. Targeting the specific molecular nodes to monitor disease and therapeutic control of CTCs in real time will likely improve the clinical management of cancer progression and metastases.

Detection of Free Radicals in Electron Beam-Irradiated Mucuna pruriens (L. DC.) Seeds by Electron Spin Resonance

Electron spin resonance (ESR) spectroscopy was employed to detect free radicals in raw Mucuna pruriens (velvet bean) seeds after electron beam irradiation (Microtron source: 0, 2.5, 5, 7.5, 10, 15 and 30 kGy) and conventional processing (roasting, powdering and cooking). The ESR signal of irradiated seeds (g=2.0055±0.0001) was more prominent in the seed coat than cotyledon. Seed coat of irradiated samples showed dose-dependent linear increase of this signal (g = 2.0055) accompanied by a weak triplet (satellite peak; aH = 3 mT) produced exclusively by radiolysis and could be used as an indication of successful irradiation. Irradiated cotyledon portion devoid of satellite peak (triplet) showed a linear increase in signal intensity up to 10 kGy with a sharp decline at higher doses (15 and 30kGy). Stability of radiation-induced ESR signals after 6 months of storage (25 ± 1°C) revealed the presence of a weak triplet with a substantial loss of signal intensity. Thermal effects such as roasting and powdering of seeds increased the signal intensity (g = 2.0055) similar to or in greater proportion than irradiation. Phenolics in seeds, which contribute significantly to detect free radicals in vegetative parts of a plant showed a waning trend in seed coat, while it was vice versa in cotyledon. Textural studies revealed significant loss in firmness after irradiation (p<0.05), which might favour in minimising the cooking time. Results of the present study might help to divulge the beneficial effects of application of electron beam irradiation technology as a better alternative to fumigants in seed preservation for safety and quarantine purposes.

Disorders of the lymphatic system of the abdomen

The lymphatic system of the abdomen comprises of the cisterna chyli, its major and minor lymphatic tributaries, and lymph nodes. Disorders of the lymphatic system of the abdomen are rarely encountered and consist of primary and secondary types. Abdominal lymphangiomas constitute the majority and have characteristic imaging features. Complicated lymphangiomas may pose a diagnostic dilemma. Generalised systemic lymphangiomatosis is a rare condition and affects major organs with a poor prognosis. Retroperitoneal lymphangiectasia in the appropriate setting might predict underlying infection, such as filariasis. Other acquired conditions include iatrogenic or treatment-induced chylocoele. Chylous ascites can be secondary to multiple causes and can be confirmed by biochemical testing and lymphangiogram in appropriate settings.

Co-Activation of Cultured Human Natural Killer Cells: Enhanced Function and Decreased Inhibition

Natural killer (NK) cells are important immune effector cells that protect the organism against viral infections and cancer. The cytotoxic activity of NK cells is induced by the engagement of a number of different activating surface receptors and controlled by inhibitory receptors to ensure self-tolerance. Resting NK cells need to be co-activated by involvement of at least two distinct activating receptors in order to induce their functional activity. However, in cultured NK cells, which have been expanded in cytokines such as interleukin (IL)-2, the engagement of a single activating receptor may be sufficient to induce their function. Data demonstrated that also cultured NK cells may be co-activated by involvement of certain combinations of activating receptors. This co-activation results in enhanced activation of Vav-1 and ERK signaling pathways and produces greater degranulation. In addition to enhanced functionality, co-activation makes NK cells more resistant to the effect of inhibitory receptors, thereby inducing more potent and efficient NK cell responses.

Emerging role of Natural killer cells in oncolytic virotherapy

Natural killer (NK) cells constitute a subtype of lymphocytes that initiate innate immune responses against tumors and virus-infected cells. The ability of NK cells to kill target cells or to produce cytokines depends on the balance between signals from activating and inhibitory cell-surface receptors. Therapies with NK cells involve activation of endogenous NK cells and/or exogenous transfer by hematopoietic stem cell transplantation/adoptive cell therapy. To exploit the diverse functional abilities of NK cells for cancer immunotherapy, it is important to understand NK cell biology and the underlying regulatory mechanisms. The state of immune suppression prevalent in malignancies creates the need for innovative therapies. Oncolytic viruses are novel anticancer agents showing selective tropism for tumor cells and lacking pathogenicity in humans, but the use of oncolytic virotherapy (OVT) presents multiple challenges. An increasing body of evidence suggests that the host immune response may critically influence the outcome of OVT. Classically, the immune system is thought to limit the efficacy of therapy through virus clearance mediated by innate immune effectors or through adaptive antiviral immune responses eliminating infected cells. Effective strategies do need to be designed in OVT to circumvent the early antiviral activity of NK cells and to augment late NK-cell-mediated antitumor responses. The intrinsic immunostimulating capacity of oncolytic viruses and the possibility of engineering them to express heterologous immunostimulatory molecules (eg, cytokines) support the use of these agents to enhance antitumor immune responses besides inducing direct oncolytic effects. OVT has indeed shown promising therapeutic outcomes in various clinical trials. Here, we review the biology of NK cells, strategies involving NK cells for achieving cancer therapy, and, more particularly, the emerging role of NK cells in OVT.

Thermoresponsive block copolymer micelles with tunable pyrrolidone-based polymer cores: structure/property correlations and application as drug carriers

Residue structure affects the physicochemical properties, drug loading efficiency, and thermoresponsive drug release profiles of block copolymer micelles with pyrrolidone-based polymer cores.

Effect of residue structure on the thermal and thermoresponsive properties of γ-substituted poly(N-acryloyl-2-pyrrolidones)

We discuss the results of an investigation into the structure/property correlations of γ-substituted poly(N-acryloyl-2-pyrrolidone)s, a recently reported class of pyrrolidone-based polymers prepared from pyroglutamic acid, a bio-derived resource.

The use of cinacalcet in pregnancy to treat a complex case of parathyroid carcinoma

We present the case of a patient with metastatic parathyroid carcinoma whose hypercalcaemia was medically managed through two pregnancies. The diagnosis was made when the patient presented with chronic knee pain and radiological findings consistent with a brown tumour, at the age of 30. Her corrected calcium and parathyroid hormone (PTH) levels were significantly elevated. Following localisation studies, a right parathyroidectomy was performed with histology revealing parathyroid carcinoma, adherent to thyroid tissue. Aged 33, following biochemical recurrence of disease, the patient underwent a second operation. A subsequent CT and FDG–PET revealed bibasal pulmonary metastases. Aged 35, the patient was referred to our unit for treatment of persistent hypercalcaemia. The focus of treatment at this time was debulking metastatic disease using radiofrequency ablation. Despite advice to the contrary, the patient conceived twice while taking cinacalcet. Even though there are limited available data regarding the use of cinacalcet in pregnancy, both pregnancies continued to term with the delivery of healthy infants, using intensive medical management for persistent hypercalcaemia.

Dysferlin regulates cell membrane repair by facilitating injury-triggered acid sphingomyelinase secretion

Dysferlin deficiency compromises the repair of injured muscle, but the underlying cellular mechanism remains elusive. To study this phenomenon, we have developed mouse and human myoblast models for dysferlinopathy. These dysferlinopathic myoblasts undergo normal differentiation but have a deficit in their ability to repair focal injury to their cell membrane. Imaging cells undergoing repair showed that dysferlin-deficit decreased the number of lysosomes present at the cell membrane, resulting in a delay and reduction in injury-triggered lysosomal exocytosis. We find repair of injured cells does not involve formation of intracellular membrane patch through lysosome-lysosome fusion; instead, individual lysosomes fuse with the injured cell membrane, releasing acid sphingomyelinase (ASM). ASM secretion was reduced in injured dysferlinopathic cells, and acute treatment with sphingomyelinase restored the repair ability of dysferlinopathic myoblasts and myofibers. Our results provide the mechanism for dysferlin-mediated repair of skeletal muscle sarcolemma and identify ASM as a potential therapy for dysferlinopathy.

Modeling the morphodynamic galectin patterning network of the developing avian limb skeleton

We present a mathematical model for the morphogenesis and patterning of the mesenchymal condensations that serve as primordia of the avian limb skeleton. The model is based on the experimentally established dynamics of a multiscale regulatory network consisting of two glycan-binding proteins expressed early in limb development: CG (chicken galectin)-1A, CG-8 and their counterreceptors that determine the formation, size, number and spacing of the "protocondensations" that give rise to the condensations and subsequently the cartilaginous elements that serve as the templates of the bones. The model, a system of partial differential and integro-differential equations containing a flux term to represent local adhesion gradients, is simulated in a "full" and a "reduced" form to confirm that the system has pattern-forming capabilities and to explore the nature of the patterning instability. The full model recapitulates qualitatively and quantitatively the experimental results of network perturbation and leads to new predictions, which are verified by further experimentation. The reduced model is used to demonstrate that the patterning process is inherently morphodynamic, with cell motility being intrinsic to it. Furthermore, subtle relationships between cell movement and the positive and negative interactions between the morphogens produce regular patterns without the requirement for activators and inhibitors with widely separated diffusion coefficients. The described mechanism thus represents an extension of the category of activator-inhibitor processes capable of generating biological patterns with repetitive elements beyond the morphostatic mechanisms of the Turing/Gierer-Meinhardt type.

Abstract P6-04-05: GPR110 overexpression increases tumorigenic potential of HER2+ breast cancer cells

Human epidermal growth factor receptor-2-overexpressing (HER2+) breast cancer is an aggressive tumor. Despite the clinical success of anti-HER2 drugs such as lapatinib (L) and trastuzumab (T), intrinsic and acquired drug resistance occurs in many patients. Identification of novel drug targets in HER2+ breast cancer is an unmet clinical need. In this context, G-protein coupled receptors (GPCRs) may be excellent drug targets because they cross-talk with the HER family members. However, the expression and function of the majority of GPCRs are unknown in HER2+ breast cancer. In a preliminary study, we examined the differential gene expression of GPCRs in anti-HER2 treatment-resistant derivatives as well as in the tumorigenic cell population, suggested to be involved in resistance, of a BT474 cell line model of HER2+ breast cancer. Anti-HER2 resistant derivatives of BT474 cells were established by long-term exposure of parental cells to increasing concentrations of L, T, or their combination (L+T). Tumorigenic cells were identified as aldehyde dehydrogenase-positive (ALDH+) cells using the Aldefluor assay. RNA was profiled using TaqMan real time RT-PCR GPCR 384-well microarray to quantify the expression of mRNA encoding 343 GPCRs. The publically available TCGA dataset was interrogated to determine differential mRNA expression of selected GPCRs in HER2+ and other subtypes of breast cancer. To determine the functional role of GPR110, BT474 cells were infected with lentiviral GPR110 construct (GPR110-OE) or empty vector (EV), and stable pools were obtained. Anchorage-dependent cell growth was evaluated using MTT cell proliferation assay over 8 days. Tumorigenic potential was determined by calculating the% of ALDH+ cells using Aldefluor assay and by evaluating the anchorage-independent cell growth using soft agar assay over 14 days. The influence of GPR110 overexpression on HER signaling pathway was investigated by measuring the levels of phosphorylated (active) and total protein levels of HER1 and HER2 using immunoblotting. GPR110 was the only GPCR overexpressed in resistant derivatives versus parental cells as well as in ALDH+ versus ALDH- cells of BT474 cells. In TCGA dataset, GPR110 expression was significantly higher in HER2+ and basal subtypes of breast cancer compared to ER+ luminal A and B subtypes. Overexpression of GPR110 in BT474 cells (9-fold in GPR110-OE vs. EV cells) resulted in a marked 5-fold increase in the number of colonies when grown in soft agar compared to EV cells even though anchorage-dependent cell growth was not significantly different between EV and GPR110-OE cells. In addition, GPR110-OE cells had a significantly higher% of ALDH+ population compared to EV cells. Phosphorylated (but not total) HER1 and HER2 protein levels were significantly higher in GPR110-OE cells compared to EV cells, suggesting hyperactive HER signaling with GPR110 overexpression. Experiments with L and T treatment will reveal the role of GPR110 in drug efficacy and acquired resistance. In summary, we show for the first time a pro-tumorigenic role of GPR110 in HER2+ breast cancer. Therefore, GPR110 may be a novel pharmacological target in HER2+ breast cancer.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-04-05.

Diagnosis and management of bone metastases

Bone metastases are a common feature of many cancers and patients with a previous history of cancer may present with bony symptoms to many different specialties. It is, however, easy to mistakenly diagnose secondary bone cancer in patients who have abnormal imaging, when the cause of the symptoms and the abnormal imaging results is benign disease. In this review, common diagnostic mistakes are described with examples of imaging of both benign and malignant bony disease. The relative risk of developing bone metastases in different cancers is discussed, as well as the rationale of different therapies for proven bony metastases, such as radiotherapy, bisphosphonate therapy, orthopaedic intervention and vertebroplasty.