Thermosensitive Cationic Magnetic Liposomes for Thermoresponsive Delivery of CPT-11 and SLP2 shRNA in Glioblastoma Treatment.

Thermosensitive cationic magnetic liposomes (TCMLs), prepared from dipalmitoylphosphatidylcholine (DPPC), cholesterol, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)]-2000, and didodecyldimethylammonium bromide (DDAB) were used in this study for the controlled release of drug/gene for cancer treatment. After co-entrapping citric-acid-coated magnetic nanoparticles (MNPs) and the chemotherapeutic drug irinotecan (CPT-11) in the core of TCML (TCML@CPT-11), SLP2 shRNA plasmids were complexed with DDAB in the lipid bilayer to prepare TCML@CPT-11/shRNA with a 135.6 ± 2.1 nm diameter. As DPPC has a melting temperature slightly above the physiological temperature, drug release from the liposomes can be triggered by an increase in solution temperature or by magneto-heating induced with an alternating magnetic field (AMF). The MNPs in the liposomes also endow the TCMLs with magnetically targeted drug delivery with guidance by a magnetic field. The successful preparation of drug-loaded liposomes was confirmed by various physical and chemical methods. Enhanced drug release, from 18% to 59%, at pH 7.4 was observed when raising the temperature from 37 to 43 °C, as well as during induction with an AMF. The in vitro cell culture experiments endorse the biocompatibility of TCMLs, whereas TCML@CPT-11 shows some enhancement of cytotoxicity toward U87 human glioblastoma cells when compared with free CPT-11. The U87 cells can be transfected with the SLP2 shRNA plasmids with very high efficiency (~100%), leading to silencing of the SLP2 gene and reducing the migration ability of U87 from 63% to 24% in a wound-healing assay. Finally, an in vivo study, using subcutaneously implanted U87 xenografts in nude mice, demonstrates that the intravenous injection of TCML@CPT11-shRNA, plus magnetic guidance and AMF treatment, can provide a safe and promising therapeutic modality for glioblastoma treatment.

Hyaluronic acid-modified, IR780-conjugated and doxorubicin-loaded reduced graphene oxide for targeted cancer chemo/photothermal/photodynamic therapy.

We used reduced graphene oxide (rGO), which has two times higher photothermal conversion efficiency than graphene oxide (GO), as a photothermal agent for cancer photothermal therapy (PTT). By conjugating a photosensitizer IR780 to rGO, the IR780-rGO could be endowed with reactive oxygen species (ROSs) generation ability for concurrent photodynamic therapy (PDT). The IR780-rGO was coated with hyaluronic acid (HA) by electrostatic interaction to facilitate its intracellular uptake by U87 glioblastoma cells. The IR780-rGO/HA was loaded with doxorubicin (DOX) for chemotherapy (CT), to develop a pH-responsive drug delivery nano-platform for targeted multimodal cancer CT/PTT/PDT. We fully characterized the properties of all nanocomposites during the synthesis steps. The high loading efficiency of DOX on IR780-rGO-HA provides 3 mg/mg drug loading, while IR780-rGO-HA/DOX shows 3 times higher drug release at endosomal pH value (pH 5) than at pH 7.4. The mechanism for PTT/PDT was confirmed from the ability of IR780-rGO-HA to induce time-dependent temperature rise, synthesis of heat shock protein 70 (HSP70) and generation of intracellular ROSs, after exposure to 808 nm near infrared (NIR) laser light. The nano-vehicle IR780-rGO-HA shows high biocompatibility toward 3T3 fibroblast and U87 cancer cell lines, as well as enhanced intracellular uptake by U87 through active targeting. This translates into increased cytotoxicity of IR780-rGO-HA/DOX, by lowering the drug half-maximal inhibitory concentration (IC50) from 0.7 to 0.46 µg/mL. This IC50 is further decreased to 0.1 µg/mL by irradiation with NIR laser for 3 min at 1.5 W/cm2. The elevated cancer cell killing mechanism was supported from flow cytometry analysis, where the highest cell apoptosis/necrosis rate was observed in combination CT/PTT/PDT. Using xenograft tumor model created by subcutaneous implantation of U87 cells in nude mice, IR780-rGO-HA/DOX delivered through intravenous (IV) injection and followed with 808 nm laser treatment for 5 min at 1.5 W/cm2 results in the lowest tumor growth rate, with negligible change of tumor volume from its original value at the end 20-day observation period. The therapeutic efficacy was supported from inhibited cell proliferation rate, increased cell apoptosis rate, and increased production of HSP70 from immunohistochemical staining of tumor tissue slices. The safety of the NIR-assisted multimodal cancer treatment could be confirmed from non-significant change of body weight and hematological parameters of blood sample. Taken together, we conclude that IV delivery of IR780-rGO-HA/DOX plus NIR laser treatment is an effective nanomedicine approach for combination cancer therapy.

Targeted delivery of irinotecan and SLP2 shRNA with GRP-conjugated magnetic graphene oxide for glioblastoma treatment.

Magnetic nanoparticles (MNPs) are useful for magnetic targeted drug delivery while ligand-mediated active targeting is another common delivery strategy for cancer therapy. In this work, we intend to prepare magnetic graphene oxide (mGO) by chemical co-precipitation of MNPs on the GO surface, followed by conjugation of the gastrin releasing peptide (GRP) as a targeting ligand, for dual targeted drug/gene delivery in invasive brain glioma treatment. mGO was grafted with chitosan, complexed with shRNA plasmid DNA for stomatin-like protein 2 (SLP2) gene silencing, modified with urocanic acid for plasmid DNA endosomal escape, PEGylated for GRP conjugation, and loaded with the chemotherapeutic drug irinotecan (CPT-11) by π-π interaction for pH-responsive drug release (mGOCUG/CPT-11/shRNA). In addition to the in depth characterization of the physico-chemical and biological properties during each preparation step, we also study the loading/pH-responsive release behavior of CPT-11 and the shRNA plasmid loading/cell transfection efficiency. The targeting and antitumor efficacies of the nanocomposite were studied with U87 human glioblastoma cells in vitro. An in vivo study revealed that intravenous administration followed by magnetic guidance results in the efficient targeted delivery of mGOCUG/CPT-11/shRNA to orthotopic brain tumors in nude mice, and it exhibits excellent antitumor efficacy with a reduced tumor growth rate and prolonged animal survival time. Our work thus highlights a multifunctional mGO-based drug/gene delivery platform for effective combination cancer therapy in glioblastoma treatment.

Potential Role and Significance of Ocular Demodicosis in Patients with Concomitant Refractory Herpetic Keratitis.

PURPOSE: To evaluate the role of Demodex infestation of the eyelids in patients with recurrent herpetic keratitis. PATIENTS AND METHODS: This is a retrospective and noncomparative case series. Twenty-seven patients with ocular demodicosis and recurrent herpetic keratitis under conventional treatments were enrolled. Demographic data and clinical photographs were collected. Ocular demodicosis was confirmed by eyelash examination under a microscope. Eyelid scrub was initiated in these patients after proving Demodex infestation. Response after treatment was reviewed. RESULTS: Herpetic keratitis was characterized by epithelial defect, including dendritic lesions (seven eyes, 25.9%), geographic ulcer (three eyes, 11.1%), and neurotrophic ulcer (two eyes, 7.4%), associated with stromal involvement in 12 cases. Six cases with stromal reactivation, including disciform keratitis (two eyes, 7.4%), immune ring (three eyes, 11.1%), and ghost vessel (one eye, 3.7%), presented no epithelial defect. Active anterior uveitis with keratic precipitates was found in 15 cases. Demodex blepharitis was diagnosed with cylindrical dandruff along their lashes in all patients. Other ocular findings include meibomian gland dysfunction (15 eyes, 55.6%), mal-aligned lashes (eight eyes, 29.6%), telangiectasia (14 eyes, 51.9%), conjunctivitis (18 eyes, 66.7%), and ocular rosacea (three eyes, 11.1%). Initial unstable clinical presentations showed deterioration of corneal melting into descemetocele, corneal perforation, recalcitrant stromal infiltration/uveitis, and uncontrollable IOP, despite antiherpetic medication. After treatment of Demodex blepharitis, infestation was under control, followed by subjective improvement of ocular symptoms and a stable clinical outcome. CONCLUSION: Ocular demodicosis should be considered in patients with unstable recurrent herpetic keratitis. A prompt diagnosis and appropriate treatment may curb the progression of herpetic corneal infection.

Injectable Thermo-Sensitive Chitosan Hydrogel Containing CPT-11-Loaded EGFR-Targeted Graphene Oxide and SLP2 shRNA for Localized Drug/Gene Delivery in Glioblastoma Therapy.

In this study, we aimed to develop a multifunctional drug/gene delivery system for the treatment of glioblastoma multiforme by combining the ligand-mediated active targeting and the pH-triggered drug release features of graphene oxide (GO). Toward this end, we load irinotecan (CPT-11) to cetuximab (CET)-conjugated GO (GO-CET/CPT11) for pH-responsive drug release after endocytosis by epidermal growth factor receptor (EGFR) over-expressed U87 human glioblastoma cells. The ultimate injectable drug/gene delivery system was designed by co-entrapping stomatin-like protein 2 (SLP2) short hairpin RNA (shRNA) and GO-CET/CPT11 in thermosensitive chitosan-g-poly(N-isopropylacrylamide) (CPN) polymer solution, which offers a hydrogel depot for localized, sustained delivery of the therapeutics after the in situ formation of CPN@GO-CET/CPT11@shRNA hydrogel. An optimal drug formulation was achieved by considering both the loading efficiency and loading content of CPT-11 on GO-CET. A sustained and controlled release behavior was found for CPT-11 and shRNA from CPN hydrogel. Confocal microscopy analysis confirmed the intracellular trafficking for the targeted delivery of CPT-11 through interactions of CET with EGFR on the U87 cell surface. The efficient transfection of U87 using SLP2 shRNA was achieved using CPN as a delivery milieu, possibly by the formation of shRNA/CPN polyplex after hydrogel degradation. In vitro cell culture experiments confirmed cell apoptosis induced by CPT-11 released from acid organelles in the cytoplasm by flow cytometry, as well as reduced SLP2 protein expression and inhibited cell migration due to gene silencing. Finally, in vivo therapeutic efficacy was demonstrated using the xenograft of U87 tumor-bearing nude mice through non-invasive intratumoral delivery of CPN@GO-CET/CPT11@shRNA by injection. Overall, we have demonstrated the novelty of this thermosensitive hydrogel to be an excellent depot for the co-delivery of anticancer drugs and siRNA. The in situ forming hydrogel will not only provide extended drug release but also combine the advantages offered by the chitosan-based copolymer structure for siRNA delivery to broaden treatment modalities in cancer therapy.

Trochlear Schwannoma Arising from Transition Zone of Nerve Sheath in the Pineal Region: Case Report and Review of the Literature.

BACKGROUND: This report presents the third case of trochlear schwannoma arising from the pineal region and the first case to be resected using a paramedian infratentorial supracerebellar approach. Schwannomas of cranial nerves have traditionally been thought to arise from the transitional point where the axonal envelopment switches from glial cells to Schwann cells; however, recent temporal bone histopathologic evidence from vestibular schwannomas challenges this view. Of the 38 cases of pathology-confirmed trochlear schwannoma in the literature, there are only 2 cases arising from the pineal region, where the nerve sheath transition zone is located. Here, we discuss an unusual case of trochlear schwannoma arising from this transition zone. CASE DESCRIPTION: A 65-year-old man was admitted to our institute after a traffic accident. He complained of headache and dizziness, and a computed tomography scan revealed an isodense mass in the pineal region with obstructive hydrocephalus. Magnetic resonance imaging with contrast showed an enhancing mass in the pineal region. The tumor was subtotally resected using a paramedian infratentorial supracerebellar approach, and pathology confirmed the diagnosis of trochlear schwannoma. CONCLUSIONS: Trochlear schwannoma should be considered when a mass is identified in the pineal region. This diagnosis should still be entertained for mass lesions along the free tentorial edge because the tumor may arise distant from the glial-Schwann transition zone located by the dorsal midbrain. We propose a treatment algorithm for this rare tumor that seeks to maximize functional outcome.