System for delivering microwave ablation to subcutaneous tumors in small-animals under high-field MRI thermometry guidance.

PURPOSE: Bio-effects following thermal treatments are a function of the achieved temperature profile in tissue, which can be estimated across tumor volumes with real-time MRI thermometry (MRIT). Here, we report on expansion of a previously developed small-animal microwave hyperthermia system integrated with MRIT for delivering thermal ablation to subcutaneously implanted tumors in mice. METHODS: Computational models were employed to assess suitability of the 2.45 GHz microwave applicators for delivering ablation to subcutaneous tumor targets in mice. Phantoms and ex-vivo tissues were heated to temperatures in the range 47-67 °C with custom-made microwave applicators for validating MRIT with the proton resonance frequency shift method against fiberoptic thermometry. HAC15 tumors implanted in nude mice (n = 6) were ablated in vivo and monitored with MRIT in multiple planes. One day post ablation, animals were euthanized, and excised tumors were processed for viability assessment. RESULTS: Average absolute error between temperatures from fiberoptic sensors and MRIT was 0.6 °C across all ex-vivo ablations. During in-vivo experiments, tumors with volumes ranging between 5.4-35.9 mm3 (mean 14.2 mm3) were ablated (duration: 103-150 s) to achieve 55 °C at the tumor boundary. Thermal doses ≥240 CEM43 were achieved across 90.7-98.0% of tumor volumes for four cases. Ablations were incomplete for remaining cases, attributed to motion-affected thermometry. Thermal dose-based ablative tumor coverage agreed with viability assessment of excised tumors. CONCLUSIONS: We have developed a system for delivering microwave ablation to subcutaneous tumors in small animals under MRIT guidance and demonstrated its performance in-vivo.

An integrated platform for small-animal hyperthermia investigations under ultra-high-field MRI guidance.

PURPOSE: Integrating small-animal experimental hyperthermia instrumentation with magnetic resonance imaging (MRI) affords real-time monitoring of spatial temperature profiles. This study reports on the development and preliminary in vivo characterisation of a 2.45 GHz microwave hyperthermia system for pre-clinical small animal investigations, integrated within a 14 T ultra-high-field MRI scanner. MATERIALS AND METHODS: The presented system incorporates a 3.5 mm (OD) directional microwave hyperthermia antenna, positioned adjacent to the small-animal target, radiating microwave energy for localised heating of subcutaneous tumours. The applicator is integrated within the 30 mm bore of the MRI system. 3D electromagnetic and biothermal simulations were implemented to characterise hyperthermia profiles from the directional microwave antenna. Experiments in tissue mimicking phantoms were performed to assess hyperthermia profiles and validate MR thermometry against fibre-optic temperature measurements. The feasibility of delivering in vivo hyperthermia exposures to subcutaneous 4T1 tumours in experimental mice under simultaneous MR thermometry guidance was assessed. RESULTS: Simulations and experiments in tissue mimicking phantoms demonstrated the feasibility of heating 21-982 mm3 targets with 8-12 W input power. Minimal susceptibility and electrical artefacts introduced by the hyperthermia applicator were observed on MR imaging. MR thermometry was in excellent agreement with fibre-optic temperatures measurements (max. discrepancy ≤0.6 °C). Heating experiments with the reported system demonstrated the feasibility of heating subcutaneous tumours in vivo with simultaneous MR thermometry. CONCLUSIONS: A platform for small-animal hyperthermia investigations under ultra-high-field MR thermometry was developed and applied to heating subcutaneous tumours in vivo.

Rationally designed peptide nanosponges for cell-based cancer therapy.

A novel type of supramolecular aggregate, named a "nanosponge" was synthesized through the interaction of novel supramolecular building blocks with trigonal geometry. The cholesterol-(K/D)nDEVDGC)3-trimaleimide unit consists of a trigonal maleimide linker to which homopeptides (either K or D) of variable lengths (n=5, 10, 15, 20) and a consensus sequence for executioner caspases (DEVDGC) are added via Michael addition. Upon mixing in aqueous buffer cholesterol-(K)nDEVDGC)3-trimaleimides and a 1:1 mixture of cholesterol-(K/D)nDEVDGC)3-trimaleimides form stable nanosponges, whereas cholesterol-(D)nDEVDGC)3-trimaleimide is unable to form supramolecular aggregates with itself. The structure of the novel nanosponges was investigated through explicit solvent and then coarse-grained molecular dynamics (MD) simulations. The nanosponges are between 80 nm and several micrometers in diameters and virtually non-toxic to monocyte/macrophage-like cells.

T1-mapping characterization of two tumor types.

T1 mapping is a quantitative method to characterize tissues with magnetic resonance imaging in a quick and efficient manner. It utilizes the relaxation rate of protons to depict the underlying structures within the imaging frame. While T1-mapping techniques are used with some frequency in areas such as cardiac imaging, their application for understanding malignancies and identifying tumor structures has yet to be thoroughly investigated. Utilizing a saturation recovery method to acquire T1 maps for two different tumor models has revealed that longitudinal relaxation mapping is sensitive enough to distinguish between normal and malignant tissue. This is seen even with decreased signal/noise ratios using small voxel sizes to obtain high-resolution images. In both tumor models, it was revealed that relaxation mapping recorded significantly different relaxation values between regions encapsulating the tumor, muscle, kidney, or spleen, as well as between the cell lines themselves. This indicates a potential future application of relaxation mapping as a method to fingerprint various stages of tumor development and may prove a useful measure to identify micro-metastases.

Characterization of a Biochemical Mouse Model of Primary Aldosteronism for Thermal Therapies.

Introduction: Aldosterone-producing adenoma (APA) is the most common cause of endocrine-related hypertension but surgery is not always feasible. Current medical interventions are associated with significant side effects and poor patient compliance. New APA animal models that replicate basic characteristics of APA and give physical and biochemical feedback are needed to test new non-surgical treatment methods, such as image-guided thermal ablation. Methods: A model of APA was developed in nude mice using HAC15 cells, a human adrenal carcinoma cell line. Tumor growth, aldosterone production, and sensitivity to angiotensin II were characterized in the model. The utility of the model was validated via treatment with microwave ablation and characterization of the resulting physical and biochemical changes in the tumor. Results: The APA model showed rapid and relatively homogeneous growth. The tumors produced aldosterone and steroid precursors in response to angiotensin II challenge, and plasma aldosterone levels were significantly higher in tumor bearing mice two hours after challenge verses non-tumor bearing mice. The model was useful for testing microwave ablation therapy, reducing aldosterone production by 80% in treated mice. Conclusion: The HAC15 model is a useful tumor model to study and develop localized treatment methods for APA.

Naïve rat umbilical cord matrix stem cells significantly attenuate mammary tumor growth through modulation of endogenous immune responses.

BACKGROUND AIMS: Un-engineered human and rat umbilical cord matrix stem cells (UCMSCs) attenuate growth of several types of tumors in mice and rats. However, the mechanism by which UCMSCs attenuate tumor growth has not been studied rigorously. METHODS: The possible mechanisms of tumor growth attenuation by rat UCMSCs were studied using orthotopic Mat B III rat mammary tumor grafts in female F344 rats. Tumor-infiltrating leukocytes were identified and quantified by immunohistochemistry analysis. Potential cytokines involved in lymphocyte infiltration in the tumors were determined by microarray and Western blot analysis. The Boyden chamber migration assay was performed for the functional analysis of identified cytokines. RESULTS: Rat UCMSCs markedly attenuated tumor growth; this attenuation was accompanied by considerable lymphocyte infiltration. Immunohistochemistry analysis revealed that most infiltrating lymphocytes in the rat UCMSC-treated tumors were CD3(+) T cells. In addition, treatment with rat UCMSCs significantly increased infiltration of CD8(+) and CD4(+) T cells and natural killer (NK) cells throughout tumor tissue. CD68(+) monocytes/macrophages and Foxp3(+) regulatory T cells were scarcely observed, only in the tumors of the phosphate-buffered saline control group. Microarray analysis of rat UCMSCs demonstrated that monocyte chemotactic protein-1 is involved in rat UCMSC-induced lymphocyte infiltration in the tumor tissues. CONCLUSIONS: These results suggest that naïve rat UCMSCs attenuated mammary tumor growth at least in part by enhancing host anti-tumor immune responses. Naïve UCMSCs can be used as powerful therapeutic cells for breast cancer treatment, and monocyte chemotactic protein-1 may be a key molecule to enhance the effect of UCMSCs at the tumor site.

In Vitro Measurement and Mathematical Modeling of Thermally-Induced Injury in Pancreatic Cancer Cells.

Thermal therapies are under investigation as part of multi-modality strategies for the treatment of pancreatic cancer. In the present study, we determined the kinetics of thermal injury to pancreatic cancer cells in vitro and evaluated predictive models for thermal injury. Cell viability was measured in two murine pancreatic cancer cell lines (KPC, Pan02) and a normal fibroblast (STO) cell line following in vitro heating in the range 42.5-50 °C for 3-60 min. Based on measured viability data, the kinetic parameters of thermal injury were used to predict the extent of heat-induced damage. Of the three thermal injury models considered in this study, the Arrhenius model with time delay provided the most accurate prediction (root mean square error = 8.48%) for all cell lines. Pan02 and STO cells were the most resistant and susceptible to hyperthermia treatments, respectively. The presented data may contribute to studies investigating the use of thermal therapies as part of pancreatic cancer treatment strategies and inform the design of treatment planning strategies.

A cell-delivered and cell-activated SN38-dextran prodrug increases survival in a murine disseminated pancreatic cancer model.

Enzyme-activated prodrugs have been investigated and sought after as highly specific, low-side-effect treatments, especially for cancer therapy. Unfortunately, excellent targets for enzyme-activated therapy are rare. Here a system based on cell delivery that can carry both a prodrug and an activating enzyme to the cancer site is demonstrated. Raw264.7 cells (mouse monocyte/macrophage-like cells, Mo/Ma) are engineered to express intracellular rabbit carboxylesterase (InCE), which is a potent activator of the prodrug irinotecan to SN38. InCE expression is regulated by the TetOn® system, which silences the gene unless a tetracycline, such as doxycycline, is present. Concurrently, an irinotecan-like prodrug, which is conjugated to dextran and can be loaded into the cytoplasm of Mo/Ma, is synthesized. To test the system, a murine pancreatic cancer model is generated by intraperitoneal (i.p.) injection of Pan02 cells. Engineered Mo/Ma are loaded with the prodrug and are injected i.p. Two days later, doxycycline was given i.p. to activate InCE, which activated the prodrug. A survival study demonstrates that this system significantly increased survival in a murine pancreatic cancer model. Thus, for the first time, a prodrug/activating enzyme system, which is self-contained within tumor-homing cells and can prolong the life of i.p. pancreatic tumor bearing mice, is demonstrated.

Stem cell-based photodynamic therapy.

We have transfected murine neural stem cells (NSCs) and rat umbilical cord matrix-derived stem cells (RUCMSCs) with a plasmid expressing gaussia luciferase (gLuc). These cells are engineered to secrete the luciferase. We have used gLuc containing supernatant from culturing the NSCs to perform in vitro photodynamic therapy of murine melanoma cells (B16F10), and RUCMSCs to perform in vivo PDT of lung melanomas in C57BL/6 mice. The treatment system was comprised of aminolevulic acid as a prodrug for the synthesis of the photosensitizer protoporphyrin IX, gaussia luciferase, and its' substrate coelenterazine. A significant reduction of the number of live melanoma cells in vitro and a borderline significant retardation of tumour growth in vivo was observed after coelenterazine-mediated PDT.

A self-contained enzyme activating prodrug cytotherapy for preclinical melanoma.

Gene-directed enzyme prodrug therapy (GDEPT) has been investigated as a means of cancer treatment without affecting normal tissues. This system is based on the delivery of a suicide gene, a gene encoding an enzyme which is able to convert its substrate from non-toxic prodrug to cytotoxin. In this experiment, we have developed a targeted suicide gene therapeutic system that is completely contained within tumor-tropic cells and have tested this system for melanoma therapy in a preclinical model. First, we established double stable RAW264.7 monocyte/macrophage-like cells (Mo/Ma) containing a Tet-On® Advanced system for intracellular carboxylesterase (InCE) expression. Second, we loaded a prodrug into the delivery cells, double stable Mo/Ma. Third, we activated the enzyme system to convert the prodrug, irinotecan, to the cytotoxin, SN-38. Our double stable Mo/Ma homed to the lung melanomas after 1 day and successfully delivered the prodrug-activating enzyme/prodrug package to the tumors. We observed that our system significantly reduced tumor weights and numbers as targeted tumor therapy after activation of the InCE. Therefore, we propose that this system may be a useful targeted melanoma therapy system for pulmonary metastatic tumors with minimal side effects, particularly if it is combined with other treatments.

A Review of In Vitro Instrumentation Platforms for Evaluating Thermal Therapies in Experimental Cell Culture Models.

Thermal therapies, the modulation of tissue temperature for therapeutic benefit, are in clinical use as adjuvant or stand-alone therapeutic modalities for a range of indications, and are under investigation for others. During delivery of thermal therapy in the clinic and in experimental settings, monitoring and control of spatio-temporal thermal profiles contributes to an increased likelihood of inducing desired bioeffects. In vitro thermal dosimetry studies have provided a strong basis for characterizing biological responses of cells to heat. To perform an accurate in vitro thermal analysis, a sample needs to be subjected to uniform heating, ideally raised from, and returned to, baseline immediately, for a known heating duration under ideal isothermal condition. This review presents an applications-based overview of in vitro heating instrumentation platforms. A variety of different approaches are surveyed, including external heating sources (i.e., CO2 incubators, circulating water baths, microheaters and microfluidic devices), microwave dielectric heating, lasers or the use of sound waves. We discuss critical heating parameters including temperature ramp rate (heat-up phase period), heating accuracy, complexity, peak temperature, and technical limitations of each heating modality.

Identification and characterization of unique tumoricidal genes in rat umbilical cord matrix stem cells.

Rat umbilical cord matrix stem cells (UCMSC) have been shown to exhibit a remarkable ability to control rat mammary adenocarcinoma (Mat B III) cell proliferation both in vivo and in vitro. To study the underlying mechanisms and genes involved in Mat B III growth attenuation, total RNA was extracted from the naive rat UCMSC alone and those cocultured with Mat B III in Transwell culture dishes. Gene expression profiles of naive rat UCMSC alone and those cocultured with Mat B III cells were investigated by microarray analysis using an Illumina RatRef-12 Expression BeadChip. The comparison of gene expression profiles between untreated and cocultured rat UCMSC identified five upregulated candidate genes (follistatin (FST), sulfatase1 (SULF-1), glucose phosphate isomerase (GPI), HtrA serine peptidase (HTRA1), and adipocyte differentiation-related protein (ADRP)) and two downregulated candidate genes (transforming growth factor, beta-induced, 68 kDa (TGFßI) and podoplanin (PDPN)) based upon the following screening criteria: (1) expression of the candidate genes should show at least a 1.5-fold change in rat UCMSC cocultured with Mat B III cells; (2) candidate genes encode secretory proteins; and (3) they encode cell growth-related proteins. Following confirmation of gene expression by real-time PCR, ADRP, SULF-1 and GPI were selected for further analysis. Addition of specific neutralizing antibodies against these three gene products or addition of gene-specific siRNA's individually in cocultures of 1:20 rat UCMSC:Mat B III cells significantly increased cell proliferation, implying that these gene products are produced under the cocultured condition and functionally attenuate cell growth. Immunoprecipitation followed by Western blot analysis demonstrated that these proteins are indeed secreted into the culture medium. Individual overexpression of these three genes in rat UCMSC significantly enhanced UCMSC-dependent inhibition of cell proliferation in coculture. These results suggest that ADRP, SULF-1 and GPI act as tumor suppressor genes, and these genes might be involved in rat UCMSC-dependent growth attenuation of rat mammary tumors.

Cytotherapy with naive rat umbilical cord matrix stem cells significantly attenuates growth of murine pancreatic cancer cells and increases survival in syngeneic mice.

BACKGROUND AIMS: Pancreatic cancer, sometimes called a 'silent killer', is one of the most aggressive human malignancies, with a very poor prognosis. It is the fourth leading cause of cancer-related morbidity and mortality in the USA. METHODS: A mouse peritoneal model was used to test the ability of unengineered rat umbilical cord matrix-derived stem cells (UCMSC) to control growth of pancreatic cancer. In vivo results were supported by various in vitro assays, such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), direct cell count, [3H]thymidine uptake and soft agar colony assays. RESULTS: Co-culture of rat UCMSC with PAN02 murine pancreatic carcinoma cells (UCMSC:PAN02, 1:6 and 1:3) caused G0/G1 arrest and significantly attenuated the proliferation of PAN02 tumor cells, as monitored by MTT assay, direct cell counts and [3H]thymidine uptake assay. Rat UCMSC also significantly reduced PAN02 colony size and number, as measured by soft agar colony assay. The in vivo mouse studies showed that rat UCMSC treatment significantly decreased the peritoneal PAN02 tumor burden 3 weeks after tumor transplantation and increased mouse survival time. Histologic study revealed that intraperitoneally administered rat UCMSC survived for at least 3 weeks, and the majority were found near or inside the tumor. CONCLUSIONS: These results indicate that naive rat UCMSC alone remarkably attenuate the growth of pancreatic carcinoma cells in vitro and in a mouse peritoneal model. This implies that UCMSC could be a potential tool for targeted cytotherapy for pancreatic cancer.

Therapy with un-engineered naïve rat umbilical cord matrix stem cells markedly inhibits growth of murine lung adenocarcinoma.

BACKGROUND: Lung cancer remains the leading cause of cancer-related mortality despite continuous efforts to find effective treatments. Data from the American Cancer Society indicate that while the overall incidence of lung cancer is declining, it continues to rise in women. Stem cell-based therapy has been an emerging strategy to treat various diseases. The purpose of this paper is to determine the efficacy of an intrinsic anti-cancer effect of rat umbilical cord matrix stem cells (UCMSCs) on lung cancer. METHODS: A mouse syngeneic lung carcinoma model was used to test the basic ability of UCMSCs to control the growth of lung cancer. Lung tumors were experimentally induced by tail vein administration of Lewis lung carcinoma (LLC) cells derived from the lung of C57BL/6 mouse. Rat UCMSCs were then administered intratracheally five days later or intravenously on days 5 and 7. The tumor burdens were determined by measuring lung weight three weeks after the treatment. RESULTS: Co-culture of rat UCMSCs with LLC significantly attenuated the proliferation of LLC cells as monitored by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), a tetrazole cell proliferation assay, thymidine uptake, and direct cell counts. In vitro colony assays with rat UCMSCs as feeder layers markedly reduced LLC colony size and number. Co-culture of rat UCMSCs with LLCs causes G0/G1 arrest of cancer cells. This is evident in the decrease of cyclin A and CDK2 expression. The in vivo studies showed that rat UCMSC treatment significantly decreased tumor weight and the total tumor mass. Histological study revealed that intratracheally or systemically administered rat UCMSCs homed to tumor areas and survived for at least 3 weeks without any evidence of differentiation or adverse effects. CONCLUSIONS: These results indicate that rat UCMSCs alone remarkably attenuate the growth of lung carcinoma cells in vitro and in a mouse syngeneic lung carcinoma graft model and could be used for targeted cytotherapy for lung cancer.

A/C magnetic hyperthermia of melanoma mediated by iron(0)/iron oxide core/shell magnetic nanoparticles: a mouse study.

BACKGROUND: There is renewed interest in magnetic hyperthermia as a treatment modality for cancer, especially when it is combined with other more traditional therapeutic approaches, such as the co-delivery of anticancer drugs or photodynamic therapy. METHODS: The influence of bimagnetic nanoparticles (MNPs) combined with short external alternating magnetic field (AMF) exposure on the growth of subcutaneous mouse melanomas (B16-F10) was evaluated. Bimagnetic Fe/Fe3O4 core/shell nanoparticles were designed for cancer targeting after intratumoral or intravenous administration. Their inorganic center was protected against rapid biocorrosion by organic dopamine-oligoethylene glycol ligands. TCPP (4-tetracarboxyphenyl porphyrin) units were attached to the dopamine-oligoethylene glycol ligands. RESULTS: The magnetic hyperthermia results obtained after intratumoral injection indicated that micromolar concentrations of iron given within the modified core-shell Fe/Fe3O4 nanoparticles caused a significant anti-tumor effect on murine B16-F10 melanoma with three short 10-minute AMF exposures. We also observed a decrease in tumor size after intravenous administration of the MNPs followed by three consecutive days of AMF exposure 24 hrs after the MNPs injection. CONCLUSIONS: These results indicate that intratumoral administration of surface modified MNPs can attenuate mouse melanoma after AMF exposure. Moreover, we have found that after intravenous administration of micromolar concentrations, these MNPs are capable of causing an anti-tumor effect in a mouse melanoma model after only a short AMF exposure time. This is a clear improvement to state of the art.

Temperature estimation for MR-guided microwave hyperthermia using block-based compressed sensing.

Mild hyperthermia has been clinically employed as an adjuvant for radiation/chemotherapy and is under investigation for precise thermally-mediated delivery of cancer therapeutic agents. Magnetic Resonance Imaging (MRI) facilitates non-invasive, real-time spatial thermometry for monitoring and guiding hyperthermia procedures. Long image acquisition time during MR-guided hyperthermia may fail to capture rapid changes in temperature. This may lead to unwanted heating of healthy tissue and/or temperature rise above hyperthermic range. We have developed a block-based compressed sensing approach to reconstruct volumetric MR-derived microwave hyperthermia temperature profiles using a subset of measured data. This algorithm exploits the sparsity of MR images due to the presence of inter- and intra-slice correlation of hyperthermic MR-derived temperature profiles. We have evaluated the performance of our developed algorithm on a phantom and in vivo in mice using previously implemented microwave applicators. This algorithm reconstructs 3D temperature profiles with PSNR of 33 dB - 49 dB in comparison to the original profiles. In summary, this study suggests that microwave hyperthermia induced temperature profiles can be reconstructed using subsamples to reduce MR image acquisition time.

Development of a Gene Delivery System Composed of a Cell-Penetrating Peptide and a Nontoxic Polymer.

Major concerns have arisen with respect to using viral vectors for gene therapies. Collateral effects include cancer resistance, development of new cancers, and even systemic deaths. For this reason, researchers have focused on the alternative of using nonviral nanocarriers for gene therapy. In this study, a gene delivery nanocarrier was developed, comprising a cell-penetrating peptide called WTAS as a primary nanocarrier and a poly(ß-amino ester) (PBAE) polymer as a secondary nanocarrier. Here, the PBAE polymer is used to protect the WTAS peptide from early degradation while further facilitating the transportation into cells. WTAS is a peptide that penetrates cell nuclei within a few minutes after exposure, which makes it an ideal candidate to transport genetic materials. The PBAE-WTAS nanocarrier was assembled and tested against three cell lines (NSC, B16F10, and GL26). Cytotoxic studies demonstrated the relatively low toxicity of the PBAE-WTAS nanocarrier and PBAE-WTAS loaded with green fluorescent protein (GFP) plasmid DNA (pDNA@PBAE-WTAS) against all three cell lines. Cell transfection experiments were carried out using GL26 cells. These studies demonstrated a very high transfection rate of PBAE-WTAS loaded with GFP plasmid DNA, leading to virtually complete transfection (> 90%). In conclusion, we report a very promising gene delivery nanocarrier, which can be further modified to transport a variety of genetic materials for targeted therapy of multiple diseases.

Peptide Nanosponges Designed for the Delivery of Perillyl Alcohol to Glioma Cells.

Peptide nanosponges of low polydispersity are spontaneously formed from trigonal supramolecular building blocks in aqueous buffers, which feature cationic and/or anionic oligopeptides (n = 5-20) and a hydrophobic unit. In contrast to classical liposomes/vesicles, nanosponges feature interwoven hydrophilic and hydrophobic nanodomains and are readily taken up by mammalian cells. Perillyl alcohol is known to be a simple, but effective small molecule drug against glioma multiforme. However, its efficacy is limited by a poor bioavailability. In order to make perillyl alcohol bioavailable, two nanosponges consisting of 10 aspartates, to which perillyl alcohol is attached by means of an ester bond, and 20 lysines or arginines (type (D-POH)10K20 and (D-POH)10R20) were synthesized, purified, and characterized by dynamic light scattering (DLS) and atomic force microscopy (AFM). These nanosponges were then tested in cell cultures of murine glioma cells (GL26) and murine neural progenitor cells (NPC) because the latter was previously utilized in cell-based cancer therapy. The two nanosponges exhibited significantly different biophysical properties (size distribution and ζ potentials). Consequently, different efficacies in killing GL26 and NPC were observed in serum-containing culture media. The results from these experiments confirmed that the type (D-POH)10K20 nanosponge is a promising candidate for the (cell-mediated) cytotherapy of glioblastoma.

Combination treatment of human umbilical cord matrix stem cell-based interferon-beta gene therapy and 5-fluorouracil significantly reduces growth of metastatic human breast cancer in SCID mouse lungs.

Umbilical cord matrix stem (UCMS) cells that were engineered to express interferon-beta (IFN-beta) were transplanted weekly for three weeks into MDA 231 breast cancer xenografts bearing SCID mice in combination with 5-fluorouracil (5-FU). The UCMS cells were found within lung tumors but not in other tissues. Although both treatments significantly reduced MDA 231 tumor area in the SCID mouse lungs, the combined treatment resulted in a greater reduction in tumor area than by either treatment used alone. These results indicate that a combination treatment of UCMS-IFN-beta cells and 5-FU is a potentially effective therapeutic procedure for breast cancer.

Combination of nanogel polyethylene glycol-polyethylenimine and 6(hydroxymethyl)-1,4-anthracenedione as an anticancer nanomedicine.

Polyethylene glycol-polyethylenimine (PEG-PEI) nanogels have been used to deliver nucleic acids and oligonucleotides into cells. First, we synthesized PEG-PEI nanogels with methylene proton ratios (CH2O:CH2N) in PEG-PEI ranging from approximately 6.8:1 to 4:1 and less, as shown by 1H NMR spectra. We first synthesized various nanogels with varying ratios of CH2O:CH2N (methylene proton) in PEG-PEI as shown by 1H NMR spectra and tested their cytotoxicity using a rodent pancreatic adenocarcinoma cell line (Pan 02). We showed that the nanogel PEG-PEI with methylene proton ratio of 4:1 was strongly cytotoxic to Pan 02 cells in vitro, while the nanogel with the methylene proton ratio of 6.8:1 was not toxic. We incorporated a novel anti-cancer drug, 6-(hydroxymethyl)-1,4-anthracenedione (AQ) analogue (AQ10) into nontoxic nanogel PEG-PEI and tested the effect of AQ10 loaded nanogel PEG-PEI (AQ10-nanogel PEG-PEI) and AQ10 dissolved in DMSO on Pan 02 cell growth. The size of this AQ10-nanogel PEG-PEI was characterized using atomic force microscopy (AFM). Our studies showed that the AQ10-nanogel PEG-PEI is readily taken up by Pan 02 cells. Growth attenuation of Pan 02 cells treated with AQ10-nanogel PEG-PEI was three to four times that of cells treated with AQ10 dissolved in DMSO. These results suggest that PEG-PEI, usually used to deliver nucleic acids into cells, can also be used to deliver an insoluble small molecule anticancer drug, AQ10.