The blood-brain barrier (BBB) remains a formidable obstacle in medicine, preventing efficient penetration of chemotherapeutic and diagnostic agents to malignant gliomas. Here, we demonstrate that a transactivator of transcription (TAT) peptide-modified gold nanoparticle platform (TAT-Au NP) with a 5 nm core size is capable of crossing the BBB efficiently and delivering cargoes such as the anticancer drug doxorubicin (Dox) and Gd3+ contrast agents to brain tumor tissues. Treatment of mice bearing intracranial glioma xenografts with pH-sensitive Dox-conjugated TAT-Au NPs via a single intravenous administration leads to significant survival benefit when compared to the free Dox. Furthermore, we demonstrate that TAT-Au NPs are capable of delivering Gd3+ chelates for enhanced brain tumor imaging with a prolonged retention time of Gd3+ when compared to the free Gd3+ chelates. Collectively, these results show promising applications of the TAT-Au NPs for enhanced malignant brain tumor therapy and non-invasive imaging.

Treatment options of glioblastoma multiforme are limited due to the blood-brain barrier (BBB). In this study, we investigated the utility of intranasal (IN) delivery as a means of transporting stem cell-based antiglioma therapeutics. We hypothesized that mesenchymal stem cells (MSCs) delivered via nasal application could impart therapeutic efficacy when expressing TNF-related apoptosis-inducing ligand (TRAIL) in a model of human glioma. ¹¹¹In-oxine, histology and magnetic resonance imaging (MRI) were utilized to track MSCs within the brain and associated tumor. We demonstrate that MSCs can penetrate the brain from nasal cavity and infiltrate intracranial glioma xenografts in a mouse model. Furthermore, irradiation of tumor-bearing mice tripled the penetration of (¹¹¹In)-oxine-labeled MSCs in the brain with a fivefold increase in cerebellum. Significant increase in CXCL12 expression was observed in irradiated xenograft tissue, implicating a CXCL12-dependent mechanism of MSCs migration towards irradiated glioma xenografts. Finally, MSCs expressing TRAIL improved the median survival of irradiated mice bearing intracranial U87 glioma xenografts in comparison with nonirradiated and irradiated control mice. Cumulatively, our data suggest that IN delivery of stem cell-based therapeutics is a feasible and highly efficacious treatment modality, allowing for repeated application of modified stem cells to target malignant glioma.

The protein known as mammalian target of rapamycin (mTOR) regulates cell growth by integrating different stimuli, such as available nutrients and mitogenic factors. The lipid messenger phosphatidic acid (PA) binds and positively regulates the mitogenic response of mTOR. PA generator enzymes are consequently potential regulators of mTOR. Here we explored the contribution to this pathway of the enzyme diacylglycerol kinase (DGK), which produces PA through phosphorylation of diacylglycerol. We found that overexpression of the DGK, but not of the ␣ isoform, in serum-deprived HEK293 cells induced mTOR-dependent phosphorylation of p70S6 kinase (p70S6K). After serum addition, p70S6K phosphorylation was higher and more resistant to rapamycin treatment in cells overexpressing DGK. The effect of this DGK isoform on p70S6K hyperphosphorylation required the mTOR PA binding region. Down-regulation of endogenous DGK by small interfering RNA in HEK293 cells diminished serum-induced p70S6K phosphorylation, highlighting the role of this isoform in the mTOR pathway. Our results confirm a role for PA in mTOR regulation and describe a novel pathway in which DGK-derived PA acts as a mediator of mTOR signaling.

BackgroundMobile phone health apps are increasingly gaining attention in oncological care as potential tools for supporting cancer patients. Although the number of publications and health apps focusing on cancer is increasing, there are still few specifically designed for the most prevalent cancers diagnosed: breast and prostate cancers. There is a need to review the effect of these apps on breast and prostate cancer patients’ quality of life (QoL) and well-being.ObjectiveThe purposes of this study were to review the scientific literature on mobile phone apps targeting breast or prostate cancer patients and involving QoL and well-being (anxiety and depression symptoms) and analyze the clinical and technological characteristics, strengths, and weaknesses of these apps, as well as patients’ user experience with them.MethodsWe conducted a systematic review of peer-reviewed literature from The Cochrane Library, Excerpta Medica Database, PsycINFO, PubMed, Scopus, and MEDLINE to identify studies involving apps focused on breast and/or prostate cancer patients and QoL and/or well-being published between January 1, 2000, and July 12, 2017. Only trial studies which met the inclusion criteria were selected. The systematic review was completed with a critical analysis of the apps previously identified in the health literature research that were available from the official app stores.ResultsThe systematic review of the literature yielded 3862 articles. After removal of duplicates, 3229 remained and were evaluated on the basis of title and abstract. Of these, 3211 were discarded as not meeting the inclusion criteria, and 18 records were selected for full text screening. Finally, 5 citations were included in this review, with a total of 644 patients, mean age 52.16 years. Four studies targeted breast cancer patients and 1 focused on prostate cancer patients. Four studies referred to apps that assessed QoL. Only 1 among the 5 analyzed apps was available from the official app store. In 3 studies, an app-related intervention was carried out, and 2 of them reported an improvement on QoL. The lengths of the app-related interventions varied from 4 to 12 weeks. Because 2 of the studies only tracked use of the app, no effect on QoL or well-being was found.ConclusionsDespite the existence of hundreds of studies involving cancer-focused mobile phone apps, there is a lack of rigorous trials regarding the QoL and/or well-being assessment in breast and/or prostate cancer patients. A strong and collective effort should be made by all health care providers to determine those cancer-focused apps that effectively represent useful, accurate, and reliable tools for cancer patients’ disease management.Trial RegistrationPROSPERO CRD42017073069; https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID= CRD42017073069 (Archived by WebCite at http://www.webcitation.org/6v38Clb9T)