Modeling of spatiotemporal dynamics of ligand-coated particle flow in targeted drug delivery processes.

Nanoparticles tethered with vasculature-binding epitopes have been used to deliver the drug into injured or diseased tissues via the bloodstream. However, the extent that blood flow dynamics affects nanoparticle retention at the target site after adhesion needs to be better understood. This knowledge gap potentially underlies significantly different therapeutic efficacies between animal models and humans. An experimentally validated mathematical model that accurately simulates the effects of blood flow on nanoparticle adhesion and retention, thus circumventing the limitations of conventional trial-and-error-based drug design in animal models, is lacking. This paper addresses this technical bottleneck and presents an integrated mathematical method that derives heavily from a unique combination of a mechanics-based dispersion model for nanoparticle transport and diffusion in the boundary layers, an asperity model to account for surface roughness of endothelium, and an experimentally calibrated stochastic nanoparticle-cell adhesion model to describe nanoparticle adhesion and subsequent retention at the target site under external flow. PLGA-b-HA nanoparticles tethered with VHSPNKK peptides that specifically bind to vascular cell adhesion molecules on the inflamed vascular wall were investigated. The computational model revealed that larger particles perform better in adhesion and retention at the endothelium for the particle sizes suitable for drug delivery applications and within physiologically relevant shear rates. The computational model corresponded closely to the in vitro experiments which demonstrates the impact that model-based simulations can have on optimizing nanocarriers in vascular microenvironments, thereby substantially reducing in vivo experimentation as well as the development costs.

In-drop thermal cycling of microcrystal assembly for senescence control (MASC) with minimal variation in efficacy.

The secretome from mesenchymal stem cells (MSCs) has recently gained attention for new therapeutics. However, clinical application requires in vitro cell manufacturing to attain enough cells. Unfortunately, this process often drives MSCs into a senescent state that drastically changes cellular secretion activities. Antioxidants are used to reverse and prevent the propagation of senescence; however, their activity is short-lived. Polymer-stabilized crystallization of antioxidants has been shown to improve bioactivity, but the broad crystal size distribution (CSD) significantly increases the efficacy variation. Efforts were made to crystalize drugs in microdroplets to narrow the CSD, but the fraction of drops containing at least one crystal can be as low as 20%. To this end, this study demonstrates that in-drop thermal cycling of hyaluronic acid-modified antioxidant crystals, named microcrystal assembly for senescence control (MASC), can drive the fraction of microdrops containing crystals to >86% while achieving significantly narrower CSDs (13±3µm) than in bulk (35±11µm). Therefore, this approach considerably improves the practicality of CSD-control in drops. In addition to exhibiting uniform release, MASC made with antioxidizing N-acetylcysteine extended the release time by 40%. MASC further improves the restoration of reactive oxygen species homeostasis in MSCs, thus minimizing cellular senescence and preserving desired secretion activities. We propose that MASC is broadly useful to controlling senescence of a wide array of therapeutic cells during biomanufacturing.

Concurrent chemoradiation and Tumor Treating Fields (TTFields, 200 kHz) for patients with newly diagnosed glioblastoma: patterns of progression in a single institution pilot study.

Current standard of care for glioblastoma (GBM) includes concurrent chemoradiation and maintenance temozolomide (TMZ) with Tumor Treating Fields (TTFields). Preclinical studies suggest TTFields and radiation treatment have synergistic effects. We conducted a pilot clinical trial of concurrent chemoradiation with TTFields and report pattern of progression. MATERIALS AND METHODS: This is a single arm pilot study (clinicaltrials.gov Identifier: NCT03477110). Adult patients (age ≥ 18 years) with KPS ≥ 60 with newly diagnosed GBM were eligible. All patients received concurrent scalp-sparing radiation (60 Gy in 30 fractions), standard concurrent TMZ and TTFields. Maintenance therapy included standard TMZ and continuation of TTFields. Radiation treatment was delivered through TTFields arrays. Incidence and location of progression was documented. Distant recurrence was defined as recurrence more than 2 cm from the primary enhancing lesion. RESULTS: Thirty patients were enrolled on the trial. Twenty were male with median age 58 years (19-77 years). Median KPS was 90 (70-100). Median follow-up was 15.2 months (1.7-23.6 months). Ten (33.3%) patients had a methylated promoter status. Twenty-seven patients (90%) had progression, with median PFS of 9.3 months (range 8.5 to 11.6 months). Six patients presented with distant recurrence, with median distance from primary lesion of 5.05 cm (2.26-6.95 cm). One infratentorial progression was noted. CONCLUSIONS: We observed improved local control using concurrent chemoradiation with TTFields for patients with newly diagnosed when compared to historical controls. Further data are needed to validate this finding. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT03477110.

Neuritin 1 Drives Therapeutic Preservation of Retinal Ganglion Cells in an Ex Vivo Human Glaucoma Model.

Purpose: Glaucoma is a leading cause of irreversible blindness. Glaucomatous intraocular pressure (IOP) triggers deleterious effects, including gliosis, optic nerve (ON) axonal retraction, neurotrophic factor deprivation, inflammation, and other pathological events, leading to retinal ganglion cell (RGC) loss. Trophic factor impairment enhances RGC apoptosis susceptibility. Neuritin 1 (NRN1), a neurotrophic protein downstream of various neurotrophins, exhibited RGC protection and regeneration in axotomy models. We evaluated human recombinant NRN1's impact on human RGCs cultured in pressurized conditions within the ex vivo translaminar autonomous system to simulate glaucoma pathogenesis. Methods: Human glaucomatous and non-glaucomatous donor eyes were obtained from eye banks according to the Declaration of Helsinki. Initially, we evaluated NRN1and RGC marker expression in glaucoma and non-glaucomatous retina to determine the NRN1 level and its association with RGC loss. Further, we evaluated NRN1's therapeutic potential by treating pressurized human eyes at normal and high IOP for seven days. Retina, ON, and conditioned medium were analyzed for RGC survival (THY1, RBPMS), gliosis (GFAP), apoptosis (CASP3, CASP7), and extracellular matrix deposition (COLIV, FN) by qRT-PCR and western blotting. Paraphenylenediamine staining assessed ON axonal degeneration, whereas ex vivo electroretinogram assessed retinal activity. Results: Glaucomatous retinas exhibited significant reductions in both NRN1 (*p = 0.007, n = 5) and RGC marker expression (*p = 0.04, n = 5). NRN1 treatment reduced gliosis, extracellular matrix deposition, ON degeneration, and increased retinal activity in pressure-perfused eyes. Conclusions: Our study confirms that NRN1 enhances human RGC survival and improves retinal function in degenerative conditions, substantiating it as a promising candidate for rescuing human RGCs from degeneration.

Evaluating two steps in transcription using a fluorescence-based electrophoretic mobility shift assay.

Transcription is the critical first step in expressing a gene, during which an RNA polymerase (RNAP) synthesizes an RNA copy of one strand of the DNA that encodes a gene. Here we describe a laboratory experiment that uses a single assay to probe two important steps in transcription: (1) RNAP binding to DNA, and (2) the transcriptional activity of the polymerase. Students probe both these steps in a single experiment using a fluorescence-based electrophoretic mobility shift assay (EMSA) and commercially available Escherichia coli RNAP. As an inquiry-driven component, students add the transcriptional inhibitor rifampicin to reactions and draw conclusions about its mechanism of inhibition by determining whether it blocks polymerase binding to DNA or transcriptional activity. Depending on the curriculum and learning goals of individual courses, this experimental module could be easily expanded to include additional experimentation that mimics a research environment more closely. After completing the experiment students understand basic principles of transcription, mechanisms of inhibition, and the use of EMSAs to probe protein/DNA interactions.

A Pilot Trial Using Telemedicine in Radiation Oncology: The Future of Health Care Is Virtual.

Background: Social determinants of health directly affect cancer survival. Driven by advances in technology and recent demands due to COVID-19, telemedicine has the ability to improve patient access to care, lower health care costs, and increase workflow efficiency. The role of telemedicine in radiation oncology is not established. Materials and Methods: We conducted an IRB-approved pilot trial using a telehealth platform for the first post-radiation visit in patients with any cancer diagnosis. The primary endpoint was feasibility of using telehealth defined by completion of five telehealth visits per month in a single department. Secondary endpoints included the ability to assess patients appropriately, patient and physician satisfaction. Physicians were surveyed again during the pandemic to determine whether viewpoints changed. Results: Between May 27, 2016 and August 1, 2018, 37 patients were enrolled in the Telehealth in Post-operative Radiation Therapy (TelePORT) trial, with 24 evaluable patients who completed their scheduled telehealth visit. On average, 1.4 patients were accrued per month. All patients were satisfied with their care, had enough time with their physician and 85.7% believed the telehealth communication was excellent. All physicians were able to accurately assess the patient's symptoms via telehealth, whereas 82.3% felt they could accurately assess treatment-related toxicity. Physicians assessing skin toxicity from breast radiation were those who did not feel they were able to assess toxicity. Discussion and Conclusions: Both health care providers and patients have identified telemedicine as a suitable platform for radiation oncology visits. Although there are limitations, telemedicine has significant potential for increasing access of cancer care delivery in radiation oncology.

The Impact of Prostate Cancer Treatment on Quality of Life: A Narrative Review with a Focus on Randomized Data.

Despite excellent oncologic outcomes, the management of localized prostate cancer remains complex and is dependent on multiple factors, including patient life expectancy, medical comorbidities, tumor characteristics, and genetic risk factors. Decades of iterative clinical trials have improved the optimization and utilization of surgical and radiation-based modalities, as well as their combinatorial use with anti-androgen and systemic therapies. While cure rates are high and converging on equivalent disease control should an upfront surgical or radiotherapeutic approach be optimized, the long-term side effects of surgical and radiation-based treatments can differ significantly in nature. Decisions regarding the selection of therapy are therefore best made in an informed and shared medical decision-making process between clinician and patient with respect to cancer control as well as adverse effects. We outline in this narrative review an understanding regarding implications of surgical and radiation treatment on quality of life after treatment, and how these data may be considered in the context of advising patients regarding the selection of therapy. This narrative review largely focuses on the quality of life data obtained from prospective randomized trials of men treated for prostate cancer. We believe this provides the best assessment of the quality of life and can be used to inform patients when making treatment decisions.