Citations

Zinc (Zn2+) is the second most abundant trace element, but is considered a micronutrient, as it is a cofactor for many enzymes and transcription factors. Whereas Zn2+ deficiency can cause cognitive immune or metabolic dysfunction and infertility, excess Zn2+ is nephrotoxic. As for other ions and solutes, Zn2+ is moved into and out of cells by specific membrane transporters: ZnT, Zip, and NRAMP/DMT proteins. ZIP10 is reported to be localized at the apical membrane of renal proximal tubules in rats, where it is believed to play a role in Zn2+ import. Renal regulation of Zn2+ is of particular interest in light of growing evidence that Zn2+ may play a role in kidney stone formation. The objective of this study was to show that ZIP10 homologs transport Zn2+, as well as ZIP10, kidney localization across species. We cloned ZIP10 from dog, human, and Drosophila ( CG10006), tested clones for Zn2+ uptake in Xenopus oocytes and localized the protein in renal structures. CG10006, rather than foi (fear-of-intimacy, CG6817) is the primary ZIP10 homolog found in Drosophila Malpighian tubules. The ZIP10 antibody recognizes recombinant dog, human, and Drosophila ZIP10 proteins. Immunohistochemistry reveals that ZIP10 in higher mammals is found not only in the proximal tubule, but also in the collecting duct system. These ZIP10 proteins show Zn2+ transport. Together, these studies reveal ZIP10 kidney localization, a role in renal Zn2+ transport, and indicates that CG10006 is a Drosophila homolog of ZIP10.

Orthotopic liver transplantation remains the only curative therapy for inborn errors of metabolism. Given the tremendous success for primary immunodeficiencies using ex-vivo gene therapy with lentiviral vectors, there is great interest in developing similar curative therapies for metabolic liver diseases. We have previously generated a pig model of hereditary tyrosinemia type 1 (HT1), an autosomal recessive disorder caused by deficiency of fumarylacetoacetate hydrolase (FAH). Using this model, we have demonstrated curative ex-vivo gene and cell therapy using a lentiviral vector to express FAH in autologous hepatocytes. To further evaluate the long-term clinical outcomes of this therapeutic approach, we continued to monitor one of these pigs over the course of three years. The animal continued to thrive off the protective drug NTBC, gaining weight appropriately, and maintaining sexual fecundity for the course of his life. The animal was euthanized 31 months after transplantation to perform a thorough biochemical and histological analysis. Biochemically, liver enzymes and alpha-fetoprotein levels remained normal and abhorrent metabolites specific to HT1 remained corrected. Liver histology showed no evidence of tumorigenicity and Masson’s trichrome staining revealed minimal fibrosis and no evidence of cirrhosis. FAH-immunohistochemistry revealed complete repopulation of the liver by transplanted FAH-positive cells. A complete histopathological report on other organs, including kidney, revealed no abnormalities. This study is the first to demonstrate long-term safety and efficacy of hepatocyte-directed gene therapy in a large animal model. We conclude that hepatocyte-directed ex-vivo gene therapy is a rational choice for further exploration as an alternative therapeutic approach to whole organ transplantation for metabolic liver disease, including HT1.

Recent progress in the treatment of advanced melanoma has led to unprecedented improvements in overall survival and, as these new melanoma treatments have been developed and deployed in the clinic, much has been learned about the natural history of the disease. Now is the time to apply that knowledge toward the design and clinical evaluation of new chemoprevention agents. Melanoma chemoprevention has the potential to reduce dramatically both the morbidity and the high costs associated with treating patients who have metastatic disease. In this work, scientific and clinical melanoma experts from the national Melanoma Prevention Working Group, composed of National Cancer Trials Network investigators, discuss research aimed at discovering and developing (or repurposing) drugs and natural products for the prevention of melanoma and propose an updated pipeline for translating the most promising agents into the clinic. The mechanism of action, preclinical data, epidemiological evidence, and results from available clinical trials are discussed for each class of compounds. Selected keratinocyte carcinoma chemoprevention studies also are considered, and a rationale for their inclusion is presented. These data are summarized in a table that lists the type and level of evidence available for each class of agents. Also included in the discussion is an assessment of additional research necessary and the likelihood that a given compound may be a suitable candidate for a phase 3 clinical trial within the next 5 years.

Background and Purpose― We aimed to determine whether low-frequency electric field navigated repetitive transcranial magnetic stimulation to noninjured motor cortex versus sham repetitive transcranial magnetic stimulation avoiding motor cortex could improve arm motor function in hemiplegic stroke patients when combined with motor training. Methods― Twelve outpatient US rehabilitation centers enrolled participants between May 2014 and December 2015. We delivered 1 Hz active or sham repetitive transcranial magnetic stimulation to noninjured motor cortex before each of eighteen 60-minute therapy sessions over a 6-week period, with outcomes measured at 1 week and 1, 3, and 6 months after end of treatment. The primary end point was the percentage of participants improving ≥5 points on upper extremity Fugl-Meyer score 6 months after end of treatment. Secondary analyses assessed changes on the upper extremity Fugl-Meyer and Action Research Arm Test and Wolf Motor Function Test and safety. Results― Of 199 participants, 167 completed treatment and follow-up because of early discontinuation of data collection. Upper extremity Fugl-Meyer gains were significant for experimental ( P <0.001) and sham groups ( P <0.001). Sixty-seven percent of the experimental group (95% CI, 58%–75%) and 65% of sham group (95% CI, 52%–76%) improved ≥5 points on 6-month upper extremity Fugl-Meyer ( P =0.76). There was also no difference between experimental and sham groups in the Action Research Arm Test ( P =0.80) or the Wolf Motor Function Test ( P =0.55). A total of 26 serious adverse events occurred in 18 participants, with none related to the study or device, and with no difference between groups. Conclusions― Among patients 3 to 12 months poststroke, goal-oriented motor rehabilitation improved motor function 6 months after end of treatment. There was no difference between the active and sham repetitive transcranial magnetic stimulation trial arms. Clinical Trial Registration― URL: https://www.clinicaltrials.gov . Unique identifier: NCT02089464.

Abstract Recently, the use of oncolytic viruses encoding the sodium-iodide symporter (NIS) has become an attractive approach to achieve radionuclide imaging of cancer. However, the potential of virus-induced NIS expression to facilitate therapy with radioactive 131I has not been fully explored. We designed a tumor-selective, infectivity-improved oncolytic adenovirus (Ad5/3-Cox2-NIS-ADP) modified to express high quantities of NIS. This virus induced radioisotope uptake in prostate and lung cancer cells and facilitated SPECT/CT imaging, but more importantly, supported the effective therapy with 131I. In our original vector, enhanced oncolysis was mediated by overexpression of adenoviral death protein (ADP). Although this structure was operative in detection and therapeutic regimens, we were concerned that the cytolytic effect of ADP may affect NIS membrane localization, and diminish its effectiveness as a theranostic tool. We therefore designed an identical Ad5/3-Cox2-NIS-ADP-deleted virus {ADP(-)} and assessed the impact of ADP on NIS expression and radioisotope uptake. Western blot and immunocytochemical analyses of pancreatic cancer cells infected with ADP(-) demonstrated higher NIS levels when compared to the ADP(+) counterpart. This correlated with an improved 125I uptake in vitro. SPECT/CT imaging studies assessing 99mTcO4- accumulation in mice to visualize pancreatic adenocarcinoma (PDAC) using patient-derived xenografts (PDX) showed that a single dose of ADP(-) accumulated far greater levels of 99mTcO4- when compared to ADP(+). Remarkably, ADP(-) produced stronger signal that was maintained up until day 32, and this outlasted ADP(+) and the control vector, replication-deficient AdCMV-NIS, currently employed in a clinical trial. Notably, within the PDAC, ADP(-) showed a distinct NIS cell membrane distribution pattern as it co-localized with cell membrane bound-cytokeratin-4. Unlike ADP(-), ADP(+) produced a punctate NIS staining pattern, with little to no cell membrane localization. These results support our hypothesis that ADP-cytolytic effect reduces NIS membrane localization, subsequently affecting radionuclide uptake. To evaluate the therapeutic potential of NIS-based radiotherapy, we treated mice bearing PDAC tumors with virotherapy alone or in combination with 131I. NIS-expressing OAds in combination with 131I significantly reduced tumor growth when compared to viro- or radiotherapy alone. The therapeutic effect in mice treated with ADP(-) combined with 131I outperformed that with ADP(+) or AdCMV-NIS vectors. Quantitative analyses of 131I uptake in tumor tissues with a gamma counter showed a clear trend where ADP(-) retained higher 131I uptake than ADP(+). These findings support the clinical applicability of the ADP-deleted OAd as the more sensitive tool for NIS-based cancer diagnosis and therapy. We are currently investigating the biodistributon and toxicity of our vectors in a pig model. Citation Format: Lisa Koodie, Eriko Iguchi Kawakami, Kari Jacobsen, Zuzan Cayci, Andrew Taylor, Edward W. Greeno, Robert J. Schumacher, John C. Morris, Martin E. Fernandez-Zapico, Julia Davydova. A novel oncolytic adenovirus for radioiodine therapy and imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5925.