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Figure S1. Drug dose-dependent enhancement of γ-H2AX and Rad51 expression using NanoOlaparib; Figure S2. Representative confocal microscopy images of Rad51 and Polθ immunostaining 30 minutes following irradiation.

In this study, the authors designed and fabricated novel magnetic trifunctional nanoparticles of Fe

Ovarian cancer has long been known to be the deadliest cancer associated with the female reproductive system. More than 15% of ovarian cancer patients have a defective BRCA-mediated homologous recombination repair pathway that can be therapeutically targeted with PARP inhibitors, such as Talazoparib (TLZ). The expansion of TLZ clinical approval beyond breast cancer has been hindered due to the highly potent systemic side effects resembling chemotherapeutics. Here we report the development of a novel TLZ-loaded PLGA implant (InCeT-TLZ) that sustainedly releases TLZ over 25 days directly into the peritoneal cavity (i.p.) to treat BRCA-mutated metastatic ovarian cancer (mOC). Methods: InCeT-TLZ was fabricated by dissolving TLZ and PLGA in chloroform followed by extrusion and evaporation. Drug loading and release were confirmed by HPLC. The detailed structure of InCeT-TLZ was checked by scanning electron microscopy. The in vivo therapeutic efficacy of InCeT-TLZ was carried out in a murine Brca2-/-p53R172H/-Pten-/- genetically engineered peritoneally metastatic ovarian cancer model. Treatment started 7 days post tumor inoculation. All mice were monitored by IVIS imaging once a week to confirm and track tumor growth. On day 8, mice with tumors (4-5 mm in diameter) were divided into 4 groups: PBS i.p. injection (50 μl, three times a week), empty implant i.p. implantation (2.5 mm, every 25 days), TLZ i.p. injection (0.33 mg/kg of TLZ by i.p. injection three times a week), and InCeT-TLZ i.p. implantation (2.5 mm, equal to a total amount of 10 i.p. injection doses, every 25 days). Body weight was recorded three times a week as an indicator of treatment tolerance and efficacy. Mice were sacrificed when the body weight increased by 50% of the initial weight. Results and Conclusion: The drug-loaded PLGA implant was developed for the sustained and local delivery of TLZ to treat high-grade serous ovarian cancer with a loading efficiency of 26.75 μg/mm. Implants can be easily placed into the peritoneal cavity of patients or animals with an 18-gauge clinical needle. The extended survival in InCeT-TLZ treated mice compared to the TLZ injection group indicated that the slow release of TLZ maximizes PARP inhibitor therapy in the peritoneal cavity for disseminated cancer treatment. Decrease in ascites formation within the intraperitoneal cavity of the InCeT-TLZ group suggests a promising treatment for ovarian cancer-associated ascites and disease progression. Histopathology following peritoneal InCeT-TLZ implantation showed no toxicity in any surrounding organs at risk. This approach would offer new sustained therapy options for substantially enhancing the therapeutic window, increasing cure rates, reducing mortality and suffering, and offering major enhancements in quality of life for the thousands of women diagnosed with OC yearly. Citation Format: Shicheng Yang, Needa Brown, Abigail L. Campbell, Kushi Aggarwal, Daniela M. Dinulescu, Srinivas Sridhar. Sustained delivery of PARP inhibitor Talazoparib for the treatment of BRCA deficient ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1994.

Mutations in BRCA genes are the leading cause of hereditary breast cancer. Current options to prevent cancer in these high-risk patients, such as anti-estrogen drugs and radical mastectomy, are limited by lack of efficacy, undesirable toxicities, or physical and emotional challenges. We have previously shown that PARP inhibitors can significantly delay tumor development in BRCA1-deficient mice. Here, we fabricated the PARP inhibitor talazoparib (TLZ) into spacer implants (InCeT-TLZ) for localized and sustained delivery. We hypothesized that this novel formulation will provide an effective chemopreventive strategy with minimal toxicity. TLZ was released gradually over 30 days as implants degraded. InCeT-TLZ significantly decreased proliferation and increased DNA damage in the mammary glands of BRCA1-deficient mice. Notably, the number of mice that developed hyperplasia in the mammary glands was significantly lower with InCeT-TLZ treatment compared to the control group. Meanwhile, InCeT-TLZ was also better tolerated than oral TLZ, without loss of body weight or anemia. This study provides proof of concept for a novel and safe chemopreventive strategy using localized delivery of a PARP inhibitor for high-risk individuals. Future studies will directly evaluate the effects of InCeT-TLZ for preventing tumor development.

Background: Despite medicinal advances, cancer is still a big problem requiring better diagnostic and treatment tools. Magnetic nanoparticle (MNP)-based nanosystems for multiple-purpose applications were developed for these unmet needs. Methods: This study fabricated novel trifunctional MNPs of Fe3O4@PLA-PEG for drug release, MRI and magnetic fluid hyperthermia. Result: The MNPs provided a significant loading of curcumin (∼11%) with controllable release ability, a high specific absorption rate of 82.2 W/g and significantly increased transverse relaxivity (r2 = 364.75 mM-1 s-1). The in vivo study confirmed that the MNPs enhanced MRI contrast in tumor observation and low-field magnetic fluid hyperthermia could effectively reduce the tumor size in mice bearing sarcoma 180. Conclusion: The nanocarrier has potential for drug release, cancer treatment monitoring and therapy. The authors are grateful for the financial support by AOARD under award FA2386-17-1-4042. The Spanish government is acknowledged for the “Nanotechnology in translational hyperthermia (HIPERNANO)” research network (RED2018102626-T) and for funding under the project number MAT2017-83631-C3. NTK Thanh thanks EPSRC (EP/M015157/1). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Nanoencapsulated drug delivery to solid tumors is a promising approach to overcome pharmacokinetic limitations of therapeutic drugs. However, encapsulation leads to complex drug biodistribution and delivery making analysis of delivery efficacy challenging. As proxies, nanocarrier accumulation or total tumor drug uptake in the tumor are used to evaluate delivery. Yet, these measurements fail to assess delivery of active, released drug to the target, and thus it commonly remains unknown if drug-target occupancy has been achieved. Here, we develop an approach to evaluate the delivery of encapsulated drug to the target, where residual drug target vacancy is measured using a fluorescent drug analog. In vitro measurements reveal that burst release governs drug delivery independent of nanoparticle uptake, and highlight limitations of evaluating nanoencapsulated drug delivery in these models. In vivo, however, our approach captures successful nanoencapsulated delivery, finding that tumor stromal cells drive nanoparticle accumulation and mediate drug delivery to adjacent cancer cells. These results, and generalizable approach, provide a critical advance to evaluate delivery of encapsulated drug to the drug target - the central objective of nanotherapeutics.

A new product prototype system for diagnosing vision and neurological disorders, called NeuroDotVR, is described herein: this system utilizes a novel wireless NeuroDot brain sensor [Versek C et al. J Neural Eng. 2018 Aug; 15(4):046027] that quantitatively measures visual evoked potentials and fields resulting from custom visual stimuli displayed on a smartphone housed in a virtual reality headset. The NeuroDot brain sensor is unique in that it can be operated both in regular electroencephalography mode, as well as a new electric field encephalography mode, which yields improvements in signal sensitivity and provides new diagnostic information. Steady state and transient visual evoked potentials and fields using reversing checkerboard stimuli are presented with case studies in amblyopia, glaucoma, and dark adaptation. These preliminary data sets highlight potential clinical applications that may be pursued in further product development and scientific studies.

Paige Baldwin,1,* Anders W Ohman,2,* Shifalika Tangutoori,3 Daniela M Dinulescu,2,# Srinivas Sridhar1,3,4,#1Department of Bioengineering, Northeastern University, Boston, MA, USA; 2Department of Pathology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA; 3Department of Physics, Northeastern University, Boston, MA, USA; 4Division of Radiation Oncology, Harvard Medical School, Boston, MA, USA*These authors contributed equally to this work#These senior co-authors contributed equally to this workBackground: PARP inhibitors, such as Olaparib, have advanced the treatment of ovarian cancer by providing patients with an effective and molecularly-targeted maintenance therapy. However, all orally-administered drugs, including Olaparib, must undergo first-pass metabolism. In contrast, a nanoparticle delivery system has the advantage of administering Olaparib directly into the peritoneal cavity for local treatment. Consequently, we sought to optimize the sustained-release formulation NanoOlaparib, previously deemed effective as an intravenous solid tumor treatment, for the local treatment of disseminated disease via intraperitoneal (i.p.) therapy. Methods: The tumor cell line 404, which was derived from a Brca2-/-, Tp53-/-, Pten-/- genetically engineered mouse model, exhibited high sensitivity to Olaparib in vitro. It was chosen for use in developing an i.p. spread xenograft for testing nanotherapy efficacy in vivo. NanoOlaparib as a monotherapy or in combination with cisplatin was compared to oral Olaparib alone or in combination using two different dose schedules. A pilot biodistribution study was performed to determine drug accumulation in various organs following i.p. administration. Results: Daily administration of NanoOlaparib reduced tumor growth and decreased the variability of the treatment response observed with daily oral Olaparib administration. However, systemic toxicity was observed in both the NanoOlaparib and vehicle (empty nanoparticle) treated groups. Scaling back the administration to twice weekly was well tolerated up to 100 mg/kg but reduced the effect on tumor growth. Biodistribution profiles indicated that NanoOlaparib began accumulating in tissues within an hour of administration and persisted for at least 72 hours after a single dose, exiting the peritoneal cavity faster than expected. Conclusion: NanoOlaparib must be modified for use against disseminated disease. Future avenues to develop NanoOlaparib as an i.p. therapy include a modified surface-coating to retain it in the peritoneal cavity and prevent entry into systemic circulation, in addition to targeting moieties for localization in tumor cells.Keywords: PARP inhibitor, Olaparib, intraperitoneal treatment, nanoparticle, DNA repair, ovarian cancer

PURPOSE: To evaluate the feasibility of Quantitative Ultrashort-Time-to-Echo Contrast Enhanced (QUTE-CE) MRA using ferumoxytol as a contrast agent for abdominal angiography in the kidney. METHODS: Four subjects underwent ferumoxytol-enhanced MRA with the 3D UTE Spiral VIBE WIP sequence at 3T. Image quality metrics were quantified, specifically the blood Signal-to-Noise Ratio (SNR), blood-tissue Contrast-to-Noise Ratio (CNR) and Intraluminal Signal Heterogeneity (ISH) from both the aorta and inferior vena cava (IVC). Morphometric analysis of the vessels was performed using manual approach and semi-automatic approach using Vascular Modeling ToolKit (VMTK). Image quality and branching order were compared between QUTE-CE MRA and the Gadolinium (Gd) CEMRA reference image. RESULTS: QUTE-CE MRA provides a bright blood snapshot that delineates arteries and veins equally in the same scan. The maximum SNR and CNR values were 3,282 ± 1,218 and 1,295 ± 580, respectively – significantly higher than available literature values using other CEMRA techniques. QUTE-CE MRA had lower ISH and depicted higher vessel branching order (7th vs 3rd) within the kidney compared to a standard dynamic clinical Gd CEMRA scan. Morphometric analysis yielded quantitative results for the total kidney volume, total cyst volume and for diameters of the branching arterial network down to the 7(th) branch. Vessel curvature was significantly increased (p < 0.001) in the presence of a renal cyst compared to equivalent vessels in normal kidney regions. CONCLUSION: QUTE-CE MRA is feasible for kidney angiography, providing greater detail of kidney vasculature, enabling quantitative morphometric analysis of the abdominal and intrarenal vessels and yielding metrics relevant to vascular diseases while using a contrast agent ferumoxytol that is safe for CKD patients.

Craig Versek,1 S Mohammad Ali Banijamali,2 Peter Bex,3 Kameran Lashkari,4 Sagar Kamarthi,2 Srinivas Sridhar1,5,6 1NeuroFieldz Inc, Newton, MA, USA; 2Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA, USA; 3Department of Psychology, Northeastern University, Boston, MA, USA; 4Department of Bioengineering, University of Massachusetts Dartmouth, Dartmouth, MA, USA; 5Departments of Physics, Bioengineering, and Chemical Engineering, Northeastern University, Boston, MA, USA; 6Division of Radiation Oncology, Harvard Medical School, Boston, MA, USACorrespondence: Srinivas SridharDepartment of Physics, Northeastern University, 110 Forsyth St., 111 Dana Research Center, Boston, MA, 02115, USAEmail s.sridhar@northeastern.eduBackground: Delayed Dark-Adapted vision Recovery (DAR) is a biomarker for Age-related Macular Degeneration (AMD), however its measurement is burdensome for patients and examiners.Methods: In this study, we developed a portable, wireless and user-friendly system that employs a headset with a smartphone to deliver controlled photo-bleach and monocular pattern reversal stimuli, while using custom electroencephalography (EEG) electrodes and electronics in order to measure Dark-Adapted Visual Evoked Potentials (DAVEP) objectively and separately at the peripheral and central visual field. This is achieved in one comfortable 20-minute session, without requiring subject reporting. DAVEP responses post photo-bleach for up to 15 minutes were measured concurrently from both eyes in 12 AMD-patients, 1 degenerative myopia patient, and 8 controls who had no diagnosed macular vision loss.Results: Robust positive polarity DAVEP responses were observed at 200– 500 ms from stimulus onset to scotopic stimuli that have been seldom reported and analyzed previously. The amplitude recovery of the DAVEP response was significantly delayed in AMD patients as compared to controls. We developed DAVEP1 scores, a simple metric for DAR, which classified 90% of subject eyes correctly, indicating the presence of AMD in at least one eye of all pre-confirmed subjects with this diagnosis.Conclusion: We developed a user-friendly, portable VEP system and DAVEP1 metric, which show a high potential to identify DAR-deficits in AMD-patients. This novel technology could aid in early diagnosis of AMD.Keywords: age-related macular degeneration, EEG, visual evoked potential, dark adaptation recovery, scotopic vision, portable diagnostics

International audience; This roadmap outlines the potential roles of metallic nanoparticles (MNPs) in the field of radiation therapy. MNPs made up of a wide range of materials (from Titanium, Z = 22, to Bismuth, Z = 83) and a similarly wide spectrum of potential clinical applications, including diagnostic, therapeutic (radiation dose enhancers, hyperthermia inducers, drug delivery vehicles, vaccine adjuvants, photosensitizers, enhancers of immunotherapy) and theranostic (combining both diagnostic and therapeutic), are being fabricated and evaluated. This roadmap covers contributions from experts in these topics summarizing their view of the current status and challenges, as well as expected advancements in technology to address these challenges.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

We have previously demonstrated that endothelial targeting of gold nanoparticles followed by external beam irradiation can cause specific tumor vascular disruption in mouse models of cancer. The induced vascular damage may lead to changes in tumor physiology, including tumor hypoxia, thereby compromising future therapeutic interventions. In this study, we investigate the dynamic changes in tumor hypoxia mediated by targeted gold nanoparticles and clinical radiation therapy (RT). By using noninvasive whole-body fluorescence imaging, tumor hypoxia was measured at baseline, on day 2 and day 13, post-tumor vascular disruption. A 2.5-fold increase (P

Purpose Tumor-associated antigens are a promising target of immunotherapy approaches for cancer treatments but rely on sufficient expression of the target antigen. This study investigates the expression of the carcinoembryonic antigen (CEA) on the surface of irradiated lung cancer cells in vitro using gold nanoparticles as radio-enhancer. Methods Human lung carcinoma cells A549 were irradiated and expression of CEA on the cell surface measured by flow cytometry 3 h, 24 h, and 72 h after irradiation to doses of 2 Gy, 6 Gy, 10 Gy, and 20 Gy in the presence or absence of 0.1 mg/ml or 0.5 mg/ml gold nanoparticles. CEA expression was measured as median fluorescent intensity and percentage of CEA-positive cells. Results An increase in CEA expression was observed with both increasing radiation dose and time. There was doubling in median fluorescent intensity 24 h after 20 Gy irradiation and 72 h after 6 Gy irradiation. Use of gold nanoparticles resulted in additional significant increase in CEA expression. Change in cell morphology included swelling of cells and increased internal complexity in accordance with change in CEA expression. Conclusions This study showed an increase in CEA expression on human lung carcinoma cells following irradiation. Increase in expression was observed with increasing radiation dose and in a time dependent manner up to 72 h post irradiation. The results further showed that gold nanoparticles can significantly increase CEA expression following radiotherapy.

Delayed Dark Adapted vision Recovery (DAR) is a biomarker for Age-related Macular Degeneration (AMD), however its measurement is burdensome for patients and examiners. We developed a portable, wireless, quick-setup system that employs a headset with a smartphone to deliver controlled photobleach and monocular pattern reversal stimuli, while using custom electroencephalography (EEG) electrodes and electronics in order to measure objective Dark Adapted Visual Evoked Potentials (DAVEP) at multiple locations of the visual field - all in one comfortable 20-minute session, without requiring subject reporting. DAVEP responses post photobleach (up to 15 minutes), were measured concurrently in both eyes of 13 patients with AMD and 8 others not diagnosed with AMD. New, unexpected features at high latencies were observed in the DAVEP responses to scotopic stimulus intensities. The amplitude recovery of the DAVEP response was significantly delayed in AMD patients compared with controls. We developed DAVEP1 scores, a simple metric for DAR, using it to successfully identify all 100% of AMD subjects and classify 90% of subject eyes correctly. Deficits in DAR in patients with AMD can be identified using this objective VEP based system and the DAVEP1 metric, a promising new objective biomarker for this disease that can be easily tested in a clinic.

Effective drug delivery is restricted by pathophysiological barriers in solid tumors. In human pancreatic adenocarcinoma, poorly-permeable blood vessels limit the intratumoral permeation and penetration of chemo or nanotherapeutic drugs. New and clinically viable strategies are urgently sought to breach the neoplastic barriers that prevent effective drug delivery. Here, we present an original idea to boost drug delivery by selectively knocking down the tumor vascular barrier in a human pancreatic cancer model. Clinical radiation activates the tumor endothelial-targeted gold nanoparticles to induce a physical vascular damage due to the high photoelectric interactions. Active modulation of these tumor neovessels lead to distinct changes in tumor vascular permeability. Noninvasive MRI and fluorescence studies, using a short-circulating nanocarrier with MR-sensitive gadolinium and a long-circulating nanocarrier with fluorescence-sensitive nearinfrared dye, demonstrate more than two-fold increase in nanodrug delivery, post tumor vascular modulation. Functional changes in altered tumor blood vessels and its downstream parameters, particularly, changes in Ktrans (permeability), Kep (flux rate), and Ve (extracellular interstitial volume), reflect changes that relate to augmented drug delivery. The proposed dual-targeted therapy effectively invades the tumor vascular barrier and improve nanodrug delivery in a human pancreatic tumor model and it may also be applied to other nonresectable, intransigent tumors that barely respond to standard drug therapies.

PURPOSE In situ drug release concurrent with radiation therapy has been proposed to enhance the therapeutic ratio of permanent prostate brachytherapy. Both brachytherapy sources and brachytherapy spacers have been proposed as potential eluters to release compounds, such as nanoparticles or chemotherapeutic agents. The relative effectiveness of the approaches has not been compared yet. This work models the physical dose enhancement of implantable eluters in conjunction with brachytherapy to determine which delivery mechanism provides greatest opportunity to enhance the therapeutic ratio. MATERIALS AND METHODS The combined effect of implanted eluters and radioactive sources were modeled in a manner that allowed the comparison of the relative effectiveness of different types of implantable eluters over a range of parameters. Prostate geometry, source, and spacer positions were extracted from treatment plans used for 125 I permanent prostate implants. Compound concentrations were calculated using steady-state solution to the diffusion equation including an elimination term characterized by the diffusion-elimination modulus (ϕb ). Does enhancement was assumed to be dependent on compound concentration up to a saturation concentration (csat ). Equivalent uniform dose (EUD) was used as an objective to determine the optimal configuration of eluters for a range of diffusion-elimination moduli, concentrations, and number of eluters. The compound delivery vehicle that produced the greatest enhanced dose was tallied for points in parameter space mentioned to determine the conditions under whether there are situations where one approach is preferable to the other. RESULTS The enhanced effect of implanted eluters was calculated for prostate volumes from 14 to 45 cm3 , ϕb from 0.01 to 4 mm-1 , csat from 0.05 to 7.5 times the steady-state compound concentration released from the surface of the eluter. The number of used eluters (ne ) was simulated from 10 to 60 eluters. For the region of (csat , Φ)-space that results in a large fraction of the gland being maximally sensitized, compound eluting spacers or sources produce equal increase in EUD. In the majority of the remaining (csat , Φ)-space, eluting spacers result in a greater EUD than sources even where sources often produce greater maximal physical dose enhancement. Placing eluting implants in planned locations throughout the prostate results in even greater enhancement than using only source or spacer locations. CONCLUSIONS Eluting brachytherapy spacers offer an opportunity to increase EUD during the routine brachytherapy process. Incorporating additional needle placements permits compound eluting spacer placement independent of source placement and thereby allowing a further increase in the therapeutic ratio. Additional work is needed to understand the in vivo spatial distribution of compound around eluters, and to incorporate time dependence of both compound release and radiation dose.

Talazoparib, a potent PARP inhibitor, has shown promising clinical and pre-clinical activity by inducing synthetic lethality in cancers with germline Brca1/2 mutations. Conventional oral delivery of Talazoparib is associated with significant off-target effects, therefore we sought to develop new delivery systems in the form of an implant loaded with Talazoparib for localized, slow and sustained release of the drug at the tumor site in Brca1-deficient breast cancer. Poly(lactic-co-glycolic acid) (PLGA) implants (0.8 mm diameter) loaded with subclinical dose (25 or 50 µg) Talazoparib were fabricated and characterized. In vitro studies with Brca1-deficient W780 and W0069 breast cancer cells were conducted to test sensitivity to PARP inhibition. The in vivo therapeutic efficacy of Talazoparib implants was assessed following a one-time intratumoral injection in Brca1Co/Co;MMTV-Cre;p53+/- mice and compared to drug-free implants and oral gavage. Immunohistochemistry studies were performed on tumor sections using PCNA and γ-H2AX staining. Sustained release of Talazoparib was observed over 28 days in vitro. Mice treated with Talazoparib implants showed statistically significant tumor growth inhibition compared to those receiving drug-free implants or free Talazoparib orally. Talazoparib implants were well-tolerated at both drug doses and resulted in less weight loss than oral gavage. PARP inhibition in mice treated with Talazoparib implants significantly increased double-stranded DNA damage and decreased tumor cell proliferation as shown by PCNA and γ-H2AX staining as compared to controls. These results demonstrate that localized and sustained delivery of Talazoparib via implants has potential to provide superior treatment outcomes at sub-clinical doses with minimal toxicity in patients with BRCA1 deficient tumors.

The use of PARP inhibitors in combination with radiotherapy is a promising strategy to locally enhance DNA damage in tumors. Here we show that radiation-resistant cells and tumors derived from a Pten/Trp53-deficient mouse model of advanced prostate cancer are rendered radiation sensitive following treatment with NanoOlaparib, a lipid-based injectable nanoformulation of olaparib. This enhancement in radiosensitivity is accompanied by radiation dose-dependent changes in γ-H2AX expression and is specific to NanoOlaparib alone. In animals, twice-weekly intravenous administration of NanoOlaparib results in significant tumor growth inhibition, whereas previous studies of oral olaparib as monotherapy have shown no therapeutic efficacy. When NanoOlaparib is administered prior to radiation, a single dose of radiation is sufficient to triple the median mouse survival time compared to radiation only controls. Half of mice treated with NanoOlaparib + radiation achieved a complete response over the 13-week study duration. Using ferumoxytol as a surrogate nanoparticle, MRI studies revealed that NanoOlaparib enhances the intratumoral accumulation of systemically administered nanoparticles. NanoOlaparib-treated tumors showed up to 19-fold higher nanoparticle accumulation compared to untreated and radiation-only controls, suggesting that the in vivo efficacy of NanoOlaparib may be potentiated by its ability to enhance its own accumulation. Together, these data suggest that NanoOlaparib may be a promising new strategy for enhancing the radiosensitivity of radiation-resistant tumors lacking BRCA mutations, such as those with PTEN and TP53 deletions. Mol Cancer Ther; 16(7); 1279–89. ©2017 AACR.

The rising prevalence and severity of antibiotic-resistant biofilm infections poses an alarming threat to public health worldwide. Here, biocompatible multi-compartment nanocarriers were synthesized to contain both hydrophobic superparamagnetic iron oxide nanoparticles (SPIONs) and the hydrophilic antibiotic methicillin for the treatment of medical device-associated infections. SPION co-encapsulation was found to confer unique properties, enhancing both nanocarrier relaxivity and magneticity compared to individual SPIONs. These iron oxide-encapsulating polymersomes (IOPs) penetrated 20 μm thick Staphylococcus epidermidis biofilms with high efficiency following the application of an external magnetic field. Three-dimensional laser scanning confocal microscopy revealed differential bacteria death as a function of drug and SPION loading. Complete eradication of all bacteria throughout the biofilm thickness was achieved using an optimized IOP formulation containing 40 μg/mL SPION and 20 μg/mL of methicillin. Importantly, this formulation was selectively toxic towards methicillin-resistant biofilm cells but not towards mammalian cells. These novel iron oxide-encapsulating polymersomes demonstrate that it is possible to overcome antibiotic-resistant biofilms by controlling the positioning of nanocarriers containing two or more therapeutics.

Parul Gupta,1 Manjri Singh,2 Rajiv Kumar,3 Jodi Belz,3 Rishi Shanker,4 Premendra D Dwivedi,1 Srinivas Sridhar,3 Surinder P Singh2 1CSIR-Indian Institute of Toxicological Research, Lucknow, 2CSIR-National Physical Laboratory, New Delhi, India; 3Nanomedicine Science and Technology Center, Northeastern University, Boston, MA, USA; 4Institute of Life Sciences, Ahmedabad University, Ahmedabad, India Abstract: Advances in nanotechnology have led to the design of multifunctional nanoparticles capable of cellular imaging, targeted drug delivery, and diagnostics for early cancer detection. We synthesized poly(lactic-co-glycolic acid) nanoparticles encapsulating a model radiosensitizing drug docetaxel accomplishing localized in situ delivery of the sensitizer to the tumor site. The synthesized nanoparticles have been characterized for their physicochemical properties. The in vitro cytotoxicity of drug-loaded nanoparticles has been studied on human tongue carcinoma cell line SCC-9 (ATCC-CRL-1629). Keywords: docetaxel, PLGA nanoformulation

Therapies for atherosclerotic cardiovascular disease should target early disease stages and specific vascular sites where disease occurs. Endothelial glycocalyx (GCX) degradation compromises endothelial barrier function and increases vascular permeability. This initiates pro-atherosclerotic lipids and inflammatory cells to penetrate vessel walls, and at the same time this can be leveraged for targeted drug delivery. In prior cell culture studies, GCX degradation significantly increased endothelial cell uptake of nanoparticle vehicles that are designed for drug delivery, compared to the effects of intact GCX. The present study assessed if the cell culture findings translate to selective nanoparticle uptake in animal vessels. In mice, the left carotid artery (LCA) was partially ligated to disturb blood flow, which induces GCX degradation, endothelial dysfunction, and atherosclerosis. After ligation, the LCA vessel wall exhibited a loss of continuity of the GCX layer on the intima. 10-nm gold nanospheres (GNS) coated with polyethylene glycol (PEG) were delivered intravenously. GCX degradation in the ligated LCA correlated to increased GNS infiltration of the ligated LCA wall. This suggests that GCX dysfunction, which coincides with atherosclerosis, can indeed be targeted for enhanced drug delivery, offering a new approach in cardiovascular disease therapy.

The data in this article provide details about MRI lesion segmentation using K-means and Gaussian Mixture Model-Expectation Maximization (GMM-EM) algorithms. Both K-means and GMM-EM algorithms can segment lesion area from the rest of brain MRI automatically. The performance metrics (accuracy, sensitivity, specificity, false positive rate, misclassification rate) were estimated for the algorithms and there was no significant difference between K-means and GMM-EM. In addition, lesion size does not affect the accuracy and sensitivity for either method. Keywords: Ischemic stroke, Lesion, Magnetic resonance image (MRI), Segmentation

Ming J Cheng,1,* Nandita N Bal,1,* Priya Prabakaran,1 Rajiv Kumar,2,3 Thomas J Webster,1,4 Srinivas Sridhar,1,2 Eno E Ebong1,2,5 1Department of Chemical Engineering, Northeastern University, Boston, MA, USA; 2Department of Physics, Northeastern University, Boston, MA, USA; 3Millipore Sigma, Milwaukee, WI, USA; 4Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah, Saudi Arabia; 5Department of Neuroscience, Albert Einstein College of Medicine, New York, NY, USA *These authors contributed equally to this work Background: Clinical data show shed endothelial glycocalyx (GCX) components in blood samples of atherosclerotic patients, linking atherosclerotic development to endothelial GCX integrity. Healthy GCX has pores no >7 nm, and shed GCX has even larger pores. Therefore, we suggest targeting and treating atherosclerosis-prone blood vessels by using nanoscale vehicles to deliver drugs via the nanoscale GCX as it becomes dysfunctional. Materials and methods: To test our idea, we investigated permeability of nanoparticles in endothelium, as related to a GCX expression. The present work involves nanorods, which are expected to interact with larger portions of endothelial cell (EC) membranes, due to surface area of the nanorod long axis. Conventional nanorod diameters are orders of magnitude larger than the GCX pore size, so we adapted conventional synthesis methods to fabricate ultrasmall gold nanorods (GNRs). Our ultrasmall GNRs have an aspect ratio of 3.4, with a length of 27.9±3.1 nm and a diameter of 8.2±1.4 nm. In addition, we produced GNRs that are biocompatible and fluorescently visible, by coating the surface with functionalized polyethylene glycol and Alexa Fluor 647. To study GNR–GCX interactions, we used human ECs, for species relevance. Results: Under life-like flow conditions, the human ECs are densely covered with a 1.3 µm thick layer of GCX, which coincides with minimal GNR permeability. When the GCX is weakened from lack of flow (static culture) or the presence of GCX degradation enzyme in the flow stream, the GCX shows 40% and 60% decreased thickness, respectively. GCX weakness due to lack of flow only slightly increases cellular permeability to GNRs, while GCX weakness due to the presence of enzyme in the flow leads to substantial increase in GNR permeability. Conclusion: These results clarify that the GCX structure is an avenue through which drug-carrying nanoparticles can be delivered for targeting affected blood vessels to treat atherosclerosis. Keywords: human endothelial cells, gold nanoparticles, nanorods, glycocalyx, heparan sulfate

Background and aims Endothelial surface glycocalyx shedding plays a role in endothelial dysfunction and increases vessel wall permeability, which can lead to inflammation and atherogenesis. We sought to elucidate whether a high fat diet (HFD) or disturbed blood flow conditions, both of which are atherogenic risk factors, would contribute more detrimentally to pre-atherosclerotic loss of endothelial glycocalyx integrity and vascular inflammation. Methods Six to seven week-old C57BL/6-background apolipoprotein-E-knockout (ApoE-KO) male mice were either fed a chow diet, fed a modified Western HFD, and/or subjected to a partial left carotid artery (LCA) ligation procedure to induce disturbed blood flow patterns in the LCA. Mice were sacrificed after 1 week of experimental conditions. Both LCA and right carotid artery (RCA) vessels were dissected and preserved to compare glycocalyx coverage and thickness as well as macrophage accumulation in carotid arterial walls amongst and between cohorts. Results Glycocalyx coverage of the endothelium was significantly reduced in the LCAs of HFD fed mice when compared to the control. More significant reduction in glycocalyx coverage occurred in the LCAs of mice exposed to disturbed flow by partial LCA ligation when compared to the control. No differences were found in glycocalyx coverage of RCAs from all cohorts. Regarding inflammation, no difference in macrophage accumulation in carotid arterial walls was observed when comparing the LCAs and RCAs of control and HFD fed mice. However, macrophage infiltration in vessel walls showed a 20-fold increase in the LCAs exposed to disturbed flow following ligation, when compared to control LCAs, while no such statistical difference was observed between the RCAs of the group. Conclusions In our mouse model, endothelial glycocalyx integrity was compromised more by disturbed blood flow patterns than by exposure of the carotid vessel to HFD conditions. The pathophysiological implications include endothelial dysfunction, which correlates to macrophage infiltration in vessel walls and promotes atherogenesis.

Nanoencapsulated drug delivery to solid tumors is a promising approach to overcome pharmacokinetic limitations of therapeutic drugs. However, encapsulation leads to complex drug biodistribution and delivery making analysis of delivery efficacy challenging. As proxies, nanocarrier accumulation or total tumor drug uptake in the tumor are used to evaluate delivery. Yet, these measurements fail to assess delivery of active, released drug to the target, and thus it commonly remains unknown if drug-target occupancy has been achieved. Here, we develop an approach to evaluate the delivery of encapsulated drug to the target, where residual drug target vacancy is measured using a fluorescent drug analog. In vitro measurements reveal that burst release governs drug delivery independent of nanoparticle uptake, and highlight limitations of evaluating nanoencapsulated drug delivery in these models. In vivo, however, our approach captures successful nanoencapsulated delivery, finding that tumor stromal cells drive nanoparticle accumulation and mediate drug delivery to adjacent cancer cells. These results, and generalizable approach, provide a critical advance to evaluate delivery of encapsulated drug to the drug target - the central objective of nanotherapeutics.

Encapsulating bacteria within constrained microenvironments can promote the manifestation of specialized behaviors. Using double-emulsion droplet-generating microfluidic synthesis, live Bacillus subtilis bacteria were encapsulated in a semi-permeable membrane composed of poly(ethylene glycol)-b-poly(D,L-lactic acid) (mPEG-PDLLA). This polymer membrane was sufficiently permeable to permit exponential bacterial growth, metabolite-induced gene expression, and rapid biofilm growth. The biodegradable microparticles retained structural integrity for several days and could be successfully degraded with time or sustained bacterial activity. Microencapsulated B. subtilis successfully captured and contained sodium selenite added outside the polymersomes, converting the selenite into elemental selenium nanoparticles that were selectively retained inside the polymer membrane. This remediation of selenium using polymersomes has high potential for reducing the toxicity of environmental selenium contamination, as well as allowing selenium to be harvested from areas not amenable to conventional waste or water treatment.

Despite major advances in the field of radiotherapy, healthy tissue damage continues to constrain the dose that can be prescribed in cancer therapy. Gold nanoparticles (GNPs) have been proposed as a solution to minimize radiation‐associated toxicities by enhancing the radiation dose delivered locally to tumor cells. In the current study, we investigated the application of third‐generation GNPs in two‐dimensional (2D) and three‐dimensional (3D) cell cultures and whether there is synergy between the nanoparticles and kilo‐ or mega‐voltage radiation to cause augmented cytotoxicity. The 10‐nm GNPs were found to be nontoxic in both 2D and 3D in vitro cultures of colon cancer cells at concentrations of up to 10–25 µg/ml. There was a significant increase in cell survival fraction reduction following exposure to 1 Gy of kilo‐voltage (18.3%) and 2 Gy of mega‐voltage (35.3%) radiation when the cells were incubated with 50 µg/ml of GNPs. The biocompatibility of the GNPs combined with their substantial synergy with radiation encourages further investigations into their application in targeted cancer treatment.

Mutations in BRCA genes are the leading cause of hereditary breast cancer and dramatically increase the lifetime risk of developing breast cancer. Anti-estrogen drugs are approved to reduce the risk of developing invasive breast cancer, but they are not effective for women with germline BRCA mutations and are limited by undesirable toxicities. Radical mastectomy provides a surgical option for high-risk patients for cancer prevention, but the physical and emotional challenges of such a radical surgery confirm that alternative approaches are needed. Our goal is to develop novel chemopreventive agents that are effective and safe for BRCA carriers. PARP inhibitors are effective for treating BRCA-mutated breast cancer patients, and we have shown that these drugs significantly delayed tumor development in BRCA-deficient mice. Here, we developed a novel implantable formulation of the PARP inhibitor Talazoparib for local delivery and thus provide a new therapeutic strategy for prevention of breast cancer. Talazoparib (TLZ) was encapsulated into spacer implants (InCeT-TLZ, 25 μg/mm) and is released in a linear manner from the implant over 30 days. When BRCA-deficient breast cancer cells were treated with the InCeT-TLZ implant in vitro, 83.1%±1.4% of the cells were dead after 7 days of treatment. To determine in vivo efficacy, age-matched BRCACo/Co;MMTV-Cre;p53+/-mice were randomized into three groups: empty spacers (2 mm), oral TLZ (50 μg given over 4 weeks), and InCeT-TLZ (50 μg, 2 mm). Using brachytherapy needles, spacers were implanted into mammary glands of the BRCA-deficient mice at 12, 16 and 20 weeks of age, before tumors had developed, and tissues were harvested 4 weeks after implantation. InCeT-TLZ significantly (p Citation Format: Di Zhang, Bijay Singh, Jessica Moerland, Owen Mitchell, Lizbeth Lockwood, Sarah Carapellucci, Srinivas Sridhar, Karen Liby. Localized delivery of the PARP inhibitor Talazoparib for chemoprevention of breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 12.

Poly(ADP-ribose) polymerase (PARP) inhibitors have been majorly utilized in cancers with BRCA1/2 mutations that have deficiencies in the homologous recombination (HR) DNA repair pathway. Traditionally, PARP inhibitors have been administered through oral route in the clinic but they have resulted in poor bioavailability, low tumor accumulation and high systemic toxicity. Moreover, tumors develop resistance to PARP inhibitors necessitating the development of strategies to re-sensitize these resistant tumors. To overcome these limitations, nanoparticle drug formulation has demonstrated a great potential to increase the drug concentration and accumulation at tumor sites with low systemic toxicities. Here we report the development of several nanoformulations of PARP inhibitors and observe their efficacies by systemic administration to treat various cancer diseases. We used two FDA approved PARP inhibitors (Olaparib or Talazoparib) for nanoformulations of NanoOlaparib and NanoTalazoparib, decorated with EpCAM or EGFR antibody, and tested on breast, ovarian, prostate and lung cancer with or without irradiation. In HR deficient models, the nanoformulations showed significant inhibition of tumor cell growth in vitro and in vivo. Above all, combination of PARP inhibitor with irradiation resulted in greater efficacy in lung and prostate cancer models. To overcome PARP inhibitor resistance, we formulated nanoparticles, NanoDinaciclib of cyclin-dependent kinase 12 (CDK12) inhibitor (dinaciclib) and used in combination with nanoformulation of PARP inhibitor to arrest the tumor growth in animal model. Our current research reveals that the use of CDK12 inhibitor in PARP resistant tumors further arrests tumor growth compared with monotherapy alone. Further studies will help clarify to achieve clear understanding of the mechanism of action CDK12 inhibitor to determine the best way to use PARP inhibitors beyond HR deficiency. Citation Format: Bijay Singh, Shicheng Yang, Paige Baldwin, Anne van de Ven, Srinivas Sridhar. Nanoformulations of PARP and CDK inhibitors for cancer therapy [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A104. doi:10.1158/1535-7163.TARG-19-A104