Transdifferentiation (TD), a somatic cell reprogramming process that eliminates pluripotent intermediates, creates cells that are ideal for personalized anti-cancer therapy. Here, we provide the first evidence that extracellular vesicles (EVs) from TD-derived induced neural stem cells (Exo-iNSCs) are an efficacious treatment strategy for brain cancer. We found that genetically engineered iNSCs generated EVs loaded with the tumoricidal gene product TRAIL at nearly twice the rate of their parental fibroblasts, and TRAIL produced by iNSCs was naturally loaded into the lumen of EVs and arrayed across their outer membrane (Exo-iNSC-TRAIL).
View Article and Find Full Text PDFTransdifferentiation (TD), a somatic cell reprogramming process that eliminates pluripotent intermediates, creates cells that are ideal for personalized anti-cancer therapy. Here, we provide the first evidence that extracellular vesicles (EVs) from TD-derived induced neural stem cells (Exo-iNSCs) are an efficacious treatment strategy for brain cancer. We found that genetically engineered iNSCs generated EVs loaded with the tumoricidal gene product TRAIL at nearly twice the rate as their parental fibroblasts, and the TRAIL produced by iNSCs were naturally loaded into the lumen of EVs and arrayed across their outer membrane (Exo-iNSC-TRAIL).
View Article and Find Full Text PDFAlmost all Glioblastoma (GBM) are either intrinsically resistant to the chemotherapeutical drug temozolomide (TMZ) or acquire therapy-induced mutations that cause chemoresistance and recurrence. The genome maintenance mechanisms responsible for GBM chemoresistance and hypermutation are unknown. We show that the E3 ubiquitin ligase RAD18 (a proximal regulator of TLS) is activated in a Mismatch repair (MMR)-dependent manner in TMZ-treated GBM cells, promoting post-replicative gap-filling and survival.
View Article and Find Full Text PDFAlmost all Glioblastoma (GBM) are either intrinsically resistant to the chemotherapeutical drug temozolomide (TMZ) or acquire therapy-induced mutations that cause chemoresistance and recurrence. The genome maintenance mechanisms responsible for GBM chemoresistance and hypermutation are unknown. We show that the E3 ubiquitin ligase RAD18 (a proximal regulator of TLS) is activated in a Mismatch repair (MMR)-dependent manner in TMZ-treated GBM cells, promoting post-replicative gap-filling and survival.
View Article and Find Full Text PDFAlmost all Glioblastoma (GBM) are either intrinsically resistant to the chemotherapeutical drug temozolomide (TMZ) or acquire therapy-induced mutations that cause chemoresistance and recurrence. The genome maintenance mechanisms responsible for GBM chemoresistance and hypermutation are unknown. We show that the E3 ubiquitin ligase RAD18 (a proximal regulator of TLS) is activated in a Mismatch repair (MMR)-dependent manner in TMZ-treated GBM cells, promoting post-replicative gap-filling and survival.
View Article and Find Full Text PDFFunctional precision medicine platforms are emerging as promising strategies to improve pre-clinical drug testing and guide clinical decisions. We have developed an organotypic brain slice culture (OBSC)-based platform and multi-parametric algorithm that enable rapid engraftment, treatment, and analysis of uncultured patient brain tumor tissue and patient-derived cell lines. The platform has supported engraftment of every patient tumor tested to this point: high- and low-grade adult and pediatric tumor tissue rapidly establishes on OBSCs among endogenous astrocytes and microglia while maintaining the tumor's original DNA profile.
View Article and Find Full Text PDFGenetically engineered neural stem cells (NSCs) are a promising therapy for the highly aggressive brain cancer glioblastoma (GBM); however, treatment durability remains a major challenge. We sought to define the events that contribute to dynamic adaptation of GBM during treatment with human skin-derived induced NSCs releasing the pro-apoptotic agent TRAIL (iNSC-TRAIL) and develop strategies that convert initial tumor kill into sustained GBM suppression. and analysis before, during, and after treatment revealed significant shifts in tumor transcriptome and spatial distribution as the tumors adapted to treatment.
View Article and Find Full Text PDFBackground: Tumor-homing tumoricidal neural stem cell (tNSC) therapy is a promising new strategy that recently entered human patient testing for glioblastoma (GBM). Developing strategies for tNSC therapy to overcome intratumoral heterogeneity, variable cancer cell invasiveness, and differential drug response of GBM will be essential for efficacious treatment response in the clinical setting. The aim of this study was to create novel hybrid tumor models and investigate the impact of GBM heterogeneity on tNSC therapies.
View Article and Find Full Text PDFBackground: Cytotoxic neural stem cells (NSCs) have emerged as a promising treatment for Medulloblastoma (MB), the most common malignant primary pediatric brain tumor. The lack of accurate pre-clinical models incorporating surgical resection and tumor recurrence limits advancement in post-surgical MB treatments. Using cell lines from two of the 5 distinct MB molecular sub-groups, in this study, we developed an image-guided mouse model of MB surgical resection and investigate intra-cavity NSC therapy for post-operative MB.
View Article and Find Full Text PDFThe primary cause of mortality for glioblastoma (GBM) is local tumor recurrence following standard-of-care therapies, including surgical resection. With most tumors recurring near the site of surgical resection, local delivery of chemotherapy at the time of surgery is a promising strategy. Herein drug-loaded polymer scaffolds with two distinct degradation profiles were fabricated to investigate the effect of local drug delivery rate on GBM recurrence following surgical resection.
View Article and Find Full Text PDFUnlabelled: ᅟ: Accurate and quantitative dosimetry for internal radiation therapy can be especially challenging, given the heterogeneity of patient anatomy, tumor anatomy, and source deposition. Internal radiotherapy sources such as nanoparticles and monoclonal antibodies require high resolution imaging to accurately model the heterogeneous distribution of these sources in the tumor. The resolution of nuclear imaging modalities is not high enough to measure the heterogeneity of intratumoral nanoparticle deposition or intratumoral regions, and mathematical models do not represent the actual heterogeneous dose or dose response.
View Article and Find Full Text PDFThe success of small interfering RNA (siRNA)-mediated gene silencing for cancer therapy is still limited because of its instability and poor intracellular internalization. Traditional cationic carriers cannot adequately meet the need for clinical application of siRNA. We herein report a dual-functional liposome containing a cholesterol derivative of metformin, i.
View Article and Find Full Text PDFAggressive, desmoplastic tumors are notoriously difficult to treat because of their extensive stroma, high interstitial pressure, and resistant tumor microenvironment. We have developed a combination therapy that can significantly slow the growth of large, stroma-rich tumors by causing massive apoptosis in the tumor center while simultaneously increasing nanoparticle uptake through a treatment-induced increase in the accumulation and retention of nanoparticles in the tumor. The vascular disrupting agent Combretastatin A-4 Phosphate (CA4P) is able to increase the accumulation of radiation-containing nanoparticles for internal radiation therapy, and the retention of these delivered radioisotopes is maintained over several days.
View Article and Find Full Text PDFDevelopment of an effective treatment against advanced tumors remains a major challenge for cancer immunotherapy. We have previously developed a potent mannose-modified lipid calcium phosphate (LCP) nanoparticle (NP)-based Trp2 vaccine for melanoma therapy, but because this vaccine can induce a potent anti-tumor immune response only during the early stages of melanoma, poor tumor growth inhibition has been observed in more advanced melanoma models, likely due to the development of an immune-suppressive tumor microenvironment (TME). To effectively treat this aggressive tumor, a multi-target receptor tyrosine kinase inhibitor, sunitinib base, was efficiently encapsulated into a targeted polymeric micelle nano-delivery system (SUN), working in a synergistic manner with vaccine therapy in an advanced mouse melanoma model.
View Article and Find Full Text PDFThis study describes variations in tumour growth patterns which occur when changes in the routes of inoculation and mouse strain are used to introduce tumours into established murine model systems that are known to vary in location and aggression. Intraperitoneal, subcutaneous, intravenous and hydrodynamic inoculations of B16F10 cells were compared among CD-1, C57BL/6 and Balb/c mice. Most surprisingly, allogeneic tumour growth in Balb/c mice after intravenous and hydrodynamic inoculation of B16F10 cells was faster than tumour growth in the syngeneic C57BL/6 mice.
View Article and Find Full Text PDFOver the last four years, the Lipid-Calcium-Phosphate (LCP) nanoparticle platform has shown success in a wide range of treatment strategies, recently including theranostics. The high specific drug loading of radiometals into LCP, coupled with its ability to efficiently encapsulate many types of cytotoxic agents, allows a broad range of theranostic applications, many of which are yet unexplored. In addition to providing an overview of current medical imaging modalities, this review highlights the current theranostic applications for LCP using SPECT and PET, and discusses potential future uses of the platform by comparing it with both systemically and locally delivered clinical radiotherapy options as well as introducing its applications as an MRI contrast agent.
View Article and Find Full Text PDFThe potential of low molecular weight heparin (LMWH) in anti-angiogenic therapy has been tempered by poor in vivo delivery to the tumor cell and potentially harmful side effects, such as the risk of bleeding due to heparin's anticoagulant activity. In order to overcome these limitations and further improve the therapeutic effect of LMWH, we designed a novel combination nanosystem of LMWH and ursolic acid (UA), which is also an angiogenesis inhibitor for tumor therapy. In this system, an amphiphilic LMWH-UA (LHU) conjugate was synthesized and self-assembled into core/shell nanodrugs with combined anti-angiogenic activity and significantly reduced anticoagulant activity.
View Article and Find Full Text PDFZoledronate (Zol) is a third-generation bisphosphonate that is widely used as an anti-resorptive agent for the treatment of cancer bone metastasis. While there is preclinical data indicating that bisphosphonates such as Zol have direct cytotoxic effects on cancer cells, such effect has not been firmly established in the clinical setting. This is likely due to the rapid absorption of bisphosphonates by the skeleton after intravenous (i.
View Article and Find Full Text PDFEtoposide phosphate (EP), a water-soluble anticancer prodrug, is widely used for treatment of many cancers. After administration it is rapidly converted to etoposide, its parent compound, which exhibits anticancer activity. Difficulty in parenteral administration necessitates the development of a suitable nanoparticle delivery system for EP.
View Article and Find Full Text PDFJ Control Release
November 2015
We have developed a theranostic nanoparticle delivering the model radionuclide (177)Lu based on the versatile lipid-calcium-phosphate (LCP) nanoparticle delivery platform. Characterization of (177)Lu-LCP has shown that radionuclide loading can be increased by several orders of magnitude without affecting the encapsulation efficiency or the morphology of (177)Lu-LCP, allowing consistency during fabrication and overcoming scale-up barriers typical of nanotherapeutics. The choice of (177)Lu as a model radionuclide has allowed in vivo anticancer therapy in addition to radiographic imaging via the dual decay modes of (177)Lu.
View Article and Find Full Text PDFThe objective of this study was to establish a quantitative method to evaluate the biotransportation of a drug across the cell membrane. Through the application of the law of mass conservation, the drug transportation rate was calculated based on Fick's law of passive diffusion and the Michaelis-Menten equation. The overall membrane-transportation rate was the sum of the passive diffusion rate and the carrier-mediated diffusion rate, which were calculated as the transportation mass divided by the respective rate.
View Article and Find Full Text PDFSince their inception in the 1980s, oligonucleotide-based (ON-based) therapeutics have been recognized as powerful tools that can treat a broad spectrum of diseases. The discoveries of novel regulatory methods of gene expression with diverse mechanisms of action are still driving the development of novel ON-based therapeutics. Difficulties in the delivery of this class of therapeutics hinder their in vivo applications, which forces drug delivery systems to be a prerequisite for clinical translation.
View Article and Find Full Text PDFInvasive mammals can be important reservoirs for human pathogens. A recent study showed that 12% of mongooses carried Salmonella spp. in their large intestines.
View Article and Find Full Text PDFTumors grown in a stroma-rich mouse model resembling clinically advanced bladder carcinoma with UMUC3 and NIH 3T3 cells have high levels of fibroblasts and an accelerated tumor growth rate. We used this model to investigate the synergistic effect of combined gemcitabine monophosphate (GMP) nanoparticles and Cisplatin nanoparticles (Combo NP) on tumor-associated fibroblasts (TAFs). A single injection of Combo NP had synergistic anti-tumor effects while the same molar ratio of combined GMP and Cisplatin delivered as free drug (Combo Free) fell outside of the synergistic range.
View Article and Find Full Text PDFThe promise of cancer gene therapeutics is hampered by difficulties in the in vivo delivery to the targeted tumor cells, and systemic delivery remains to be the biggest challenge to be overcome. Here, we concentrate on systemic in vivo gene delivery for cancer therapy using nonviral vectors. In this review, we summarize the existing delivery barriers together with the requirements and strategies to overcome these problems.
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