Novel Image-Guided Percutaneous Lung Tissue Excision Device With Integrated Sealing of Blood Vessels and Airways: An In Vivo Preclinical Study.

OBJECTIVE: This study evaluated the efficacy of the Minimally Invasive Targeted Resection (MiTR) device, a novel electrosurgical instrument that allows for targeted excision of a lung abnormality while using bipolar radiofrequency (RF) energy to seal blood vessels and airways. METHODS: The MiTR system was evaluated in 7 acute and 2 chronic porcine (7-day) models to evaluate the efficacy of tissue excision with bipolar RF sealing of blood vessels and airways and application of an autologous blood patch into the excised tissue cavity. Air leak was recorded for all evaluations. The study was approved by the institutional ethical board. RESULTS: Nineteen lung tissue samples, measuring 2.5 cm long × 1.2 cm diameter, were excised. In 8 of 9 animals (89%), hemostasis and pneumostasis were observed visually at the completion of the procedure. In 2 of 2 chronic animals (100%), hemostasis and pneumostasis persisted for the 7-day observation period. Histologic examination of the excised samples showed preservation of the core parenchymal architecture without evident tissue damage of the samples that would impair pathologic analysis. CONCLUSIONS: Percutaneous resection of targeted lung tissue with the MiTR system demonstrated hemostasis and pneumostasis while obtaining a histologically intact sample. After regulatory approval, the use of this device could offer more tissue for analysis than a transthoracic needle biopsy or bronchoscopy and a far less invasive alternative to video-assisted thoracic surgery or thoracotomy. This may also expand patient and physician options for the early diagnosis and treatment of lung cancer.

Vitamin B6 is governed by the local compartmentalization of metabolic enzymes during growth.

Vitamin B6 is a vital micronutrient across cell types and tissues, and dysregulated B6 levels contribute to human disease. Despite its importance, how B6 vitamer levels are regulated is not well understood. Here, we provide evidence that B6 dynamics are rapidly tuned by precise compartmentation of pyridoxal kinase (PDXK), the rate-limiting B6 enzyme. We show that canonical Wnt rapidly led to the accumulation of inactive B6 by shunting cytosolic PDXK into lysosomes. PDXK was modified with methyl-arginine Degron (MrDegron), a protein tag for lysosomes, which enabled delivery via microautophagy. Hyperactive lysosomes resulted in the continuous degradation of PDXK and B6 deficiency that promoted proliferation in Wnt-driven colorectal cancer (CRC) cells. Pharmacological or genetic disruption of the coordinated MrDegron proteolytic pathway was sufficient to reduce CRC survival in cells and organoid models. In sum, this work contributes to the repertoire of micronutrient-regulated processes that enable cancer cell growth and provides insight into the functional impact of B6 deficiencies for survival.

Doped Graphene Quantum Dots as Biocompatible Radical Scavenging Agents.

Oxidative stress is proven to be a leading factor in a multitude of adverse conditions, from Alzheimer's disease to cancer. Thus, developing effective radical scavenging agents to eliminate reactive oxygen species (ROS) driving many oxidative processes has become critical. In addition to conventional antioxidants, nanoscale structures and metal-organic complexes have recently shown promising potential for radical scavenging. To design an optimal nanoscale ROS scavenging agent, we have synthesized ten types of biocompatible graphene quantum dots (GQDs) augmented with various metal dopants. The radical scavenging abilities of these novel metal-doped GQD structures were, for the first time, assessed via the DPPH, KMnO4, and RHB (Rhodamine B protectant) assays. While all metal-doped GQDs consistently demonstrate antioxidant properties higher than the undoped cores, aluminum-doped GQDs exhibit 60-95% radical scavenging ability of ascorbic acid positive control. Tm-doped GQDs match the radical scavenging properties of ascorbic acid in the KMnO4 assay. All doped GQD structures possess fluorescence imaging capabilities that enable their tracking in vitro, ensuring their successful cellular internalization. Given such multifunctionality, biocompatible doped GQD antioxidants can become prospective candidates for multimodal therapeutics, including the reduction of ROS with concomitant imaging and therapeutic delivery to cancer tumors.

TRAF4-mediated nonproteolytic ubiquitination of androgen receptor promotes castration-resistant prostate cancer.

Castration-resistant prostate cancer (CRPC) poses a major clinical challenge with the androgen receptor (AR) remaining to be a critical oncogenic player. Several lines of evidence indicate that AR induces a distinct transcriptional program after androgen deprivation in CRPCs. However, the mechanism triggering AR binding to a distinct set of genomic loci in CRPC and how it promotes CRPC development remain unclear. We demonstrate here that atypical ubiquitination of AR mediated by an E3 ubiquitin ligase TRAF4 plays an important role in this process. TRAF4 is highly expressed in CRPCs and promotes CRPC development. It mediates K27-linked ubiquitination at the C-terminal tail of AR and increases its association with the pioneer factor FOXA1. Consequently, AR binds to a distinct set of genomic loci enriched with FOXA1- and HOXB13-binding motifs to drive different transcriptional programs including an olfactory transduction pathway. Through the surprising upregulation of olfactory receptor gene transcription, TRAF4 increases intracellular cAMP levels and boosts E2F transcription factor activity to promote cell proliferation under androgen deprivation conditions. Altogether, these findings reveal a posttranslational mechanism driving AR-regulated transcriptional reprogramming to provide survival advantages for prostate cancer cells under castration conditions.

Automated Approach to In Vitro Image-Guided Photothermal Therapy with Top-Down and Bottom-Up-Synthesized Graphene Quantum Dots.

Graphene-based materials have been the subject of interest for photothermal therapy due to their high light-to-heat conversion efficiency. Based on recent studies, graphene quantum dots (GQDs) are expected to possess advantageous photothermal properties and facilitate fluorescence image-tracking in the visible and near-infrared (NIR), while surpassing other graphene-based materials in their biocompatibility. Several GQD structures including reduced graphene quantum dots (RGQDs) derived from reduced graphene oxide via top-down oxidation and hyaluronic acid graphene quantum dots (HGQDs) hydrothermally bottom-up synthesized from molecular hyaluronic acid were employed to test these capabilities in the present work. These GQDs possess substantial NIR absorption and fluorescence throughout the visible and NIR beneficial for in vivo imaging while being biocompatible at up to 1.7 mg/mL concentrations. In aqueous suspensions, RGQDs and HGQDs irradiated with a low power (0.9 W/cm2) 808 nm NIR laser facilitate a temperature increase up to 47.0 °C, which is sufficient for cancer tumor ablation. In vitro photothermal experiments sampling multiple conditions directly in the 96-well plate were performed using an automated simultaneous irradiation/measurement system developed on the basis of a 3D printer. In this study, HGQDs and RGQDs facilitated the heating of HeLa cancer cells up to 54.5 °C, leading to the drastic inhibition of cell viability from over 80% down to 22.9%. GQD's fluorescence in the visible and NIR traces their successful internalization into HeLa cells maximized at 20 h suggesting both extracellular and intracellular photothermal treatment capabilities. The combination of the photothermal and imaging modalities tested in vitro makes the GQDs developed in this work prospective agents for cancer theragnostics.

Simplifying the B Complex: How Vitamins B6 and B9 Modulate One Carbon Metabolism in Cancer and Beyond.

Vitamin B micronutrients are essential regulators of one carbon metabolism that ensures human health. Vitamin B9, or folate, lies at the heart of the folate cycle and converges with the methionine cycle to complete the one carbon pathway. Additionally, vitamin B6 contributes by orchestrating the flux of one carbon cycling. Dysregulation of vitamin B contributes to altered biochemical signaling that manifests in a spectrum of human diseases. This review presents an analysis of the past, present, and future work, highlighting the interplay between folate and vitamin B6 in one carbon metabolism. Emerging insights include advances in metabolomic-based mass spectrometry and the use of live-cell metabolic labeling. Cancer is used as a focal point to dissect vitamin crosstalk and highlight new insights into the roles of folate and vitamin B6 in metabolic control. This collection of vitamin-based research detailing the trends of one carbon metabolism in human disease exemplifies how the future of personalized medicine could unfold using this new base of knowledge and ultimately provide next-generation therapeutics.

Detection of Pancreatic Cancer miRNA with Biocompatible Nitrogen-Doped Graphene Quantum Dots.

Early-stage pancreatic cancer remains challenging to detect, leading to a poor five-year patient survival rate. This obstacle necessitates the development of early detection approaches based on novel technologies and materials. In this work, the presence of a specific pancreatic cancer-derived miRNA (pre-miR-132) is detected using the fluorescence properties of biocompatible nitrogen-doped graphene quantum dots (NGQDs) synthesized using a bottom-up approach from a single glucosamine precursor. The sensor platform is comprised of slightly positively charged (1.14 ± 0.36 mV) NGQDs bound via π-π stacking and/or electrostatic interactions to the negatively charged (-22.4 ± 6.00 mV) bait ssDNA; together, they form a complex with a 20 nm average size. The NGQDs' fluorescence distinguishes specific single-stranded DNA sequences due to bait-target complementarity, discriminating them from random control sequences with sensitivity in the micromolar range. Furthermore, this targetability can also detect the stem and loop portions of pre-miR-132, adding to the practicality of the biosensor. This non-invasive approach allows cancer-specific miRNA detection to facilitate early diagnosis of various forms of cancer.

Selective inhibition of peripheral cathepsin S reverses tactile allodynia following peripheral nerve injury in mouse.

Cathepsin S (CatS) is a cysteine protease found in lysosomes of hematopoietic and microglial cells and in secreted form in the extracellular space. While CatS has been shown to contribute significantly to neuropathic pain, the precise mechanisms remain unclear. In this report, we describe JNJ-39641160, a novel non-covalent, potent, selective and orally-available CatS inhibitor that is peripherally restricted (non-CNS penetrant) and may represent an innovative class of immunosuppressive and analgesic compounds and tools useful toward investigating peripheral mechanisms of CatS in neuropathic pain. In C57BL/6 mice, JNJ-39641160 dose-dependently blocked the proteolysis of the invariant chain, and inhibited both T-cell activation and antibody production to a vaccine antigen. In the spared nerve injury (SNI) model of chronic neuropathic pain, in which T-cell activation has previously been demonstrated to be a prerequisite for the development of pain hypersensitivity, JNJ-39641160 fully reversed tactile allodynia in wild-type mice but was completely ineffective in the same model in CatS knockout mice (which exhibited a delayed onset in allodynia). By contrast, in the acute mild thermal injury (MTI) model, JNJ-39641160 only weakly attenuated allodynia at the highest dose tested. These findings support the hypothesis that blockade of peripheral CatS alone is sufficient to fully reverse allodynia following peripheral nerve injury and suggest that the mechanism of action likely involves interruption of T-cell activation and peripheral cytokine release. In addition, they provide important insights toward the development of selective CatS inhibitors for the treatment of neuropathic pain in humans.

Cutaneous Branch of the Obturator Nerve Extending to the Medial Ankle and Foot: A Report of Two Cadaveric Cases.

The area of skin supplied by the cutaneous branch of the obturator nerve (CBO) is highly variable. Although most introductory anatomy texts describe the CBO as innervating only a portion of the medial thigh, there are numerous reports in the literature of CBOs passing the knee to innervate the proximal, middle, or even distal leg. There are no previous reports of CBOs extending to the ankle and foot. Herein we describe 2 cases of CBOs extending at least to the medial foot. Both cases were discovered incidentally, during routine cadaver dissections by osteopathic and podiatric medical students in the anatomy laboratory of Western University of Health Sciences in California. In both instances, the anomalously long CBOs shared several characteristics: (1) they arose as direct branches of the anterior division of the obturator nerve, not from the subsartorial plexus; (2) they coursed immediately posterior to the great saphenous vein from the distal thigh to the distal leg, only deviating away from the saphenous vein just above the medial malleolus; and (3) they terminated in radiating fibers to the posterior half of the medial ankle and foot. In both cases, the saphenous branch of the femoral nerve was present but restricted to the area anterior to the great saphenous vein. It is likely that the variant CBOs carried fibers of the L4 spinal nerve and thus provided cutaneous innervation to the medial foot and ankle, a function most commonly reserved for the saphenous branch of the femoral nerve distal to the knee. Saphenous neuropathy is a common postoperative complication of saphenous cutdowns for coronary artery bypass grafts, so the potential involvement of a long CBO can add additional complexity to regional anesthetic blocks for foot and ankle surgery and procedures such as vein harvesting for coronary artery bypass grafts.

Collision Risk Mitigation of Varian TrueBeam Linear Accelerator With Supplemental Live-View Cameras.

BACKGROUND: Noncoplanar radiation therapy techniques such as 4π have potential dosimetric advantages but introduce complexities in treatment delivery that increase the risk for collision. Direct or remote visual confirmation of clearance is a safeguard against collisions of the gantry, couch, and patient. With our institution's Varian TrueBeam system, we identified configurations that cannot be visualized with the included closed-circuit television cameras. At our practice, electronic, portal imaging device (EPID) collision risk also exists because of the routine deployment to capture exit-dose images for treatment quality assurance. We propose a simple, cost-effective solution using network cameras to help eliminate blind spots that permits safe, noncoplanar arrangements with an EPID-acquired exit dose. METHODS AND MATERIALS: Two Panasonic cameras were installed overhead while a third Panasonic camera was mounted onto the pedestal to monitor the couch undersurface. Live views from each camera were accessed with a web-based client. The EPID and gantry were visually assessed at 52 couch and gantry rotational angle configurations at 6 couch translational positions. Visibility was compared for the standard and supplemental camera setups at each configuration (χ2 test). RESULTS: Of the 294 assessable couch-gantry configurations, the standard camera setup had limited visibility of either gantry or EPID for 146 configurations compared with 72 configurations with additional cameras (51% blind-spot reduction; P < .01). An 87% blind-spot reduction was observed for our laterally centered, cranial-based, couch translational position (P < .01). CONCLUSIONS: The supplemental cameras were simple, effective additions for collision detection, especially for noncoplanar radiation therapy with EPID-acquired, exit-dose imaging. Over half of the assessable noncoplanar configurations had blind spots using standard cameras, which was reduced to <25% with additional cameras. In practice, there were almost no blind spots for patients with brain tumors who were treated with our templated beam arrangements. Using live-view camera feeds, vault re-entry to visually confirm clearance was reduced approximately 10-fold, which increased the treatment efficiency. In the most recent 12 months, no collision or near-collision events have been reported.

Lens Dose-Response Prediction Modeling and Cataract Incidence in Patients With Retinoblastoma After Lens-Sparing or Whole-Eye Radiation Therapy.

PURPOSE: We retrospectively assessed the incidence of cataracts in patients with retinoblastoma (Rb) treated with either lens-sparing radiation therapy (LSRT) or whole-eye radiation therapy (WERT). A secondary aim of this study was to model the dose-response risk of cataract. METHODS AND MATERIALS: We reviewed 65 patients with Rb treated with radiation therapy (RT) at Children's Hospital, Los Angeles from 1997 to 2015. Eyes that were enucleated before RT or lacked follow-up eye examinations were excluded. All patients underwent computed tomography simulation, and mean lens dose data were collected. Follow-up ophthalmologic examinations and intraocular lens implant history were reviewed for cataracts. The primary event-free survival (EFS) outcome was cataract development. Eyes without cataracts were censored on the last date of eye examination or post-RT enucleation, if applicable. Kaplan-Meier estimates were used to compare EFS outcomes, and dose response was projected with Cox regression and logistic regression models. RESULTS: Sixty-one patients (94 eyes) were analyzed with a median follow-up of 51.8 months. For eyes treated with WERT, cataracts developed in 71.7% versus 35.3% for LSRT. Median EFS for WERT and LSRT were 20.8 and 67.9 months, respectively. Compared with WERT, a significant EFS benefit was demonstrated for LSRT (P < .001). Mean lens dose had a significant effect on cataracts in both Cox regression and logistic regression models (P < .01). The mean lens dose of 7 Gy was projected to have a 5-year cataract incidence of 20% and 25% with the logistic and Cox regression models, respectively. CONCLUSIONS: We report the first clinical data demonstrating significantly improved EFS in patients with Rb treated with LSRT. Through lens dose-response modeling, we validate a mean lens dose threshold of 7 Gy to keep cataract risk below 25%. Although RT is used less often for Rb owing to advances in chemotherapy delivery options, these findings are relevant for refining lens dose constraints, particularly in children who have received radiation dose near the orbit.

Tripeptide analogues of MG132 as protease inhibitors.

The 26S proteasome and calpain are linked to a number of important human diseases. Here, we report a series of analogues of the prototypical tripeptide aldehyde inhibitor MG132 that show a unique combination of high activity and selectivity for calpains over proteasome. Tripeptide aldehydes (1-3) with an aromatic P3 substituent show enhanced activity and selectivity against ovine calpain 2 relative to chymotrypsin-like activity of proteasome. Docking studies reveal the key contacts between inhibitors and calpain to confirm the importance of the S3 pocket with respect to selectivity between calpains 1 and 2 and the proteasome.

Evaluation of weekly paclitaxel plus carboplatin followed by anthracycline chemotherapy on the neoadjuvant treatment of patients with triple-negative breast cancer.

OBJECTIVE: To evaluate the effectiveness and tolerability of neoadjuvant chemotherapy with weekly paclitaxel in combination with weekly carboplatin area under curve 2 followed by anthracycline chemotherapy. PATIENTS AND METHODS: This is a retrospective review of electronic medical records of patients (N = 32) with stage 1c-III triple-negative breast cancer. Patients received neoadjuvant chemotherapy with paclitaxel 80 mg/m2 once per week for 12 weeks in combination with carboplatin area under curve 2 once per week for 12 weeks (wP + wCb), followed by a standard anthracycline regimen including either doxorubicin 60 mg/m2 and cyclophosphamide 600 mg/m2 every 2 or 3 weeks, or epirubicin 90 mg/m2 and cyclophosphamide 600 mg/m2 every 3 weeks for four cycles with myeloid growth factor support. RESULTS: Most patients (91%) received all 12 cycles of wP + wCb, and 88% received all four planned cycles of anthracycline chemotherapy. Of the patients, 84% completed all planned therapies. The complete pathologic response rate was 60%. In terms of hematologic toxicity, 96% of the patients experienced grade ≥3 leucopenia, 40% grade ≥3 anemia, and 15% grade ≥3 thrombocytopenia, and neutropenic fever was seen in 22% of the patients. CONCLUSION: The combination of neoadjuvant chemotherapy with wP + wCb before anthracycline chemotherapy can be tolerated by patients with triple-negative breast cancer. Complete pathologic response rates were comparable with those historically seen. Careful selection of patients is fundamental as this regimen is associated with a high incidence of hematologic toxicity.

Nonalcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) defines a condition of hepatic steatosis with or without hepatic injury. NAFLD is increasing in prevalence worldwide and presents a public health burden. Most patients are asymptomatic, although some present with fatigue and right upper quadrant pain. NAFLD is discovered incidentally when patients have elevated liver enzymes or fatty liver is seen on imaging modalities. Imaging studies can confirm fatty deposits in the liver, but needle biopsy is needed to determine degree of inflammation. The mainstay of treatment is weight loss and controlling diabetes and hyperlipidemia. Liver transplantation is considered when disease progresses to cirrhosis.

Stereotactic Radiosurgery and Ipilimumab Versus Stereotactic Radiosurgery Alone in Melanoma Brain Metastases.

Benefits of stereotactic radiosurgery (SRS) have been well established in melanoma brain metastases (MBM). Immunotherapy agents such as ipilimumab (ipi) have recently demonstrated clinical efficacy in advanced disease as well. The theoretical synergistic effects of combining these therapies in MBM have not been explored in detail, however, we conducted a systematic review with meta-analysis of studies that compared combined SRS and ipi versus SRS alone in MBM. Medical Literature Analysis and Retrieval System Online (MEDLINE) and Central databases were used for our literature search, which was conducted by three reviewers. We included studies that examined SRS and ipilimumab compared to SRS alone in MBM. Pertinent results were tabulated in a standardized spreadsheet. Newcastle-Ottawa Scale (NOS) Risk of Bias Assessment and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method for rating evidence quality were used for qualitative analysis. Review Manager was used for statistical analysis. We identified four cohort studies that compared SRS plus ipi versus SRS alone in MBM. As per the GRADE criteria, we found low-quality evidence for survival benefits associated with combined treatment. Meta-analysis confirmed a significant benefit in survival for SRS and ipilimumab (hazard ratio 0.38, 95% confidence interval 0.28 - 0.52, p < 0.01). There were no significant differences between comparison groups for local control, distant brain control, radiation necrosis, or intracranial bleeding. We conclude that low-quality evidence exists for superior overall survival in MBM treated with SRS and ipilimumab compared to SRS without ipilimumab. There is also no increased risk of radiation necrosis and/or intracranial bleeding with combining radiation and immunotherapy in this setting.

Impressive Response to Concomitant Platinum-based Chemotherapy and Yttrium-90 in a Patient with Heavily Pretreated Triple-negative Breast Cancer Widely Metastasized to the Liver.

Metastatic triple-negative breast cancer (TNBC) constitutes a heterogeneous group of diseases with systemic treatment options limited to cytotoxic chemotherapy at the time being. The disease tends to affect visceral organs more frequently when compared to hormone receptor-positive breast cancer. The prognoses of patients with heavily pretreated disease affecting the liver are very dismal. We present the response to radioembolization and systemic chemotherapy in a seriously ill patient who had undergone previous lines of chemotherapy for TNBC with extensive liver metastases.

Vectored immunoprophylaxis protects humanized mice from mucosal HIV transmission.

The vast majority of new HIV infections result from relatively inefficient transmission of the virus across mucosal surfaces during sexual intercourse. A consequence of this inefficiency is that small numbers of transmitted founder viruses initiate most heterosexual infections. This natural bottleneck to transmission has stimulated efforts to develop interventions that are aimed at blocking this step of the infection process. Despite the promise of this strategy, clinical trials of preexposure prophylaxis have had limited degrees of success in humans, in part because of lack of adherence to the recommended preexposure treatment regimens. In contrast, a number of existing vaccines elicit systemic immunity that protects against mucosal infections, such as the vaccines for influenza and human papilloma virus. We recently demonstrated the ability of vectored immunoprophylaxis (VIP) to prevent intravenous transmission of HIV in humanized mice using broadly neutralizing antibodies. Here we demonstrate that VIP is capable of protecting humanized mice from intravenous as well as vaginal challenge with diverse HIV strains despite repeated exposures. Moreover, animals receiving VIP that expresses a modified VRC07 antibody were completely resistant to repetitive intravaginal challenge by a heterosexually transmitted founder HIV strain, suggesting that VIP may be effective in preventing vaginal transmission of HIV between humans.

Calcium phosphate-bearing matrices induce osteogenic differentiation of stem cells through adenosine signaling.

Synthetic matrices emulating the physicochemical properties of tissue-specific ECMs are being developed at a rapid pace to regulate stem cell fate. Biomaterials containing calcium phosphate (CaP) moieties have been shown to support osteogenic differentiation of stem and progenitor cells and bone tissue formation. By using a mineralized synthetic matrix mimicking a CaP-rich bone microenvironment, we examine a molecular mechanism through which CaP minerals induce osteogenesis of human mesenchymal stem cells with an emphasis on phosphate metabolism. Our studies show that extracellular phosphate uptake through solute carrier family 20 (phosphate transporter), member 1 (SLC20a1) supports osteogenic differentiation of human mesenchymal stem cells via adenosine, an ATP metabolite, which acts as an autocrine/paracrine signaling molecule through A2b adenosine receptor. Perturbation of SLC20a1 abrogates osteogenic differentiation by decreasing intramitochondrial phosphate and ATP synthesis. Collectively, this study offers the demonstration of a previously unknown mechanism for the beneficial role of CaP biomaterials in bone repair and the role of phosphate ions in bone physiology and regeneration. These findings also begin to shed light on the role of ATP metabolism in bone homeostasis, which may be exploited to treat bone metabolic diseases.

Synthesis and extended activity of triazole-containing macrocyclic protease inhibitors.

Peptide-derived protease inhibitors are an important class of compounds with the potential to treat a wide range of diseases. Herein, we describe the synthesis of a series of triazole-containing macrocyclic protease inhibitors pre-organized into a ß-strand conformation and an evaluation of their activity against a panel of proteases. Acyclic azido-alkyne-based aldehydes are also evaluated for comparison. The macrocyclic peptidomimetics showed considerable activity towards calpain II, cathepsin L and S, and the 20S proteasome chymotrypsin-like activity. Some of the first examples of highly potent macrocyclic inhibitors of cathepsin S were identified. These adopt a well-defined ß-strand geometry as shown by NMR spectroscopy, X-ray analysis, and molecular docking studies.