pH/Redox-Triggered Photothermal Treatment for Cancer Therapy Based on a Dual-Responsive Cationic Polymer Dot.

In the present study, a pH/redox-responsive cationic polymer dot (CD) was successfully prepared for a near-infrared (NIR)-mediated, simultaneously controllable photothermal temperature guided imaging off/on system to monitor therapeutic delivery. Carbonized disulfide cross-linked branched polyethyleneimine (bPEI) was conjugated with folic acid (FA) as a targeting moiety and partially formed an ionic complex with anionic indocyanine green (ICG) to afford a bPEI-based CD (ICG-CD). This was responsive to mild reductive (glutathione, GSH) and acidic tumor conditions, which enabled the simultaneous biodegradation of those hydrophobic and complex sites. The ICG-CD internalized readily into the cytoplasm of cancer cells by a FA receptor and cationic-mediated endocytosis in the off state, whereas if ICG-CD met intracellular GSH at high concentrations, GSH contributed partially to the recovery of fluorescence and was then internalized into acidic endosomes to induce complete restoration of fluorescence. This tumor-sensitive degradability of the CD not only facilitated ICG release in the tumor location but also allowed controllable photothermal therapy effects of nanoparticles under NIR irradiation, which resulted in improved cancer therapy. Taken together, the results indicate great potential in tumor targeting, intracellular imaging, and controllable therapeutic delivery through a fluorescence off/on assay under the pH/redox conditions of cancer cells.

Photo-based PDT/PTT dual model killing and imaging of cancer cells using phycocyanin-polypyrrole nanoparticles.

Photodynamic therapy (PDT) and photothermal therapy (PTT) using nanoparticles have gained significant attention for its therapeutic effect for cancer treatment. In the present study, we fabricated polypyrrole nanoparticles by employing bovine serum albumin-phycocyanin complex and the formulated particles were stable in various physiological solutions like water, phosphate buffered saline and culture media. The formulated nanoparticles did not cause any noticeable toxicity to MDA-MB-231 and HEK-293 cells. The obtained nanoparticles effectively killed MDA-MB-231 cells in a dual way upon laser illumination, one is through phycocyanin propagated reactive oxygen species (PDT) upon laser illumination and in another way it eradicated the treated cells by converting optical energy into heat energy (PTT). Additionally, the nanoparticles generated good amplitude of ultrasound signals under photoacoustic imaging (PAT) system that facilitates imaging of treated cells. In conclusion, the fabricated particles could be used as a multimodal therapeutic agent for treatment of cancer in the biomedical field.

Magnetic hydroxyapatite: a promising multifunctional platform for nanomedicine application.

In this review, specific attention is paid to the development of nanostructured magnetic hydroxyapatite (MHAp) and its potential application in controlled drug/gene delivery, tissue engineering, magnetic hyperthermia treatment, and the development of contrast agents for magnetic resonance imaging. Both magnetite and hydroxyapatite materials have excellent prospects in nanomedicine with multifunctional therapeutic approaches. To date, many research articles have focused on biomedical applications of nanomaterials because of which it is very difficult to focus on any particular type of nanomaterial. This study is possibly the first effort to emphasize on the comprehensive assessment of MHAp nanostructures for biomedical applications supported with very recent experimental studies. From basic concepts to the real-life applications, the relevant characteristics of magnetic biomaterials are patented which are briefly discussed. The potential therapeutic and diagnostic ability of MHAp-nanostructured materials make them an ideal platform for future nanomedicine. We hope that this advanced review will provide a better understanding of MHAp and its important features to utilize it as a promising material for multifunctional biomedical applications.

Functionalized biocompatible WO3 nanoparticles for triggered and targeted in vitro and in vivo photothermal therapy.

We report on dopamine-conjugated hyaluronic acid (HA-D), a mussel-inspired facile capping material that can modify tungsten oxide (WO3) nanoparticles to be both biocompatible and targetable, allowing precise delivery (WO3-HA) to a tumor site. Near-infrared (NIR) irradiated WO3-HA showed a rapid and substantial rise in photothermal heat to complete in vitro thermolysis of malignant MDAMB and A549 cancer cellsbut was found to be relatively less sensitive to normal MDCK cells. A long-term in vivo investigation of ~10 nm HA thickness on WO3 (WO3-HA) nanoparticles demonstrated efficient photo-thermal conversion with time-dependent tumor target accumulation. This long-termin vivo survival study ofWO3-HA showed promising biocompatibility, with a complete recovery from malignant tumor. Due to the importance of keeping simplicity in the design of therapeutic nanoparticles, we therefore expect that this facile scheme (HA-D) would contribute to the biocompatible development of versatile metallic nanoparticles for photothermal applications.

Papillary thyroid carcinoma with exclusive involvement of a functioning recurrent laryngeal nerve may be treated with shaving technique.

OBJECTIVES: We sought to validate the feasibility of preserving a functioning recurrent laryngeal nerve (RLN) invaded by papillary thyroid carcinoma (PTC) using a shaving technique followed by high-dose radioactive iodine (RAI) therapy. METHODS: A retrospective review of 34 patients with locally invasive PTC who had exclusive tumor involvement of a functioning RLN was performed. All patients underwent total thyroidectomy and high-dose RAI therapy. A shaving technique was conducted with the goal of leaving the smallest amount of residual tumor as possible while attempting to preserve nerve function. Clinicopathologic factors and oncologic outcomes of the patients with resected RLN (group A, n = 14) and preserved RLN (group B, n = 20) were compared. RESULTS: The two groups showed no differences in clinicopathologic factors or follow-up period. Mean dose of radioiodine therapy was 245.0 ± 140.3 mCi (range 100-540 mCi). Permanent postoperative vocal cord paralysis after RLN shaving occurred in two patients of group B (10%). Only one patient (5%) in group B had local recurrence at the thyroid bed where the residual tumor was located. The overall recurrence rate was 35.7% (5/14) and 20.0% (4/20) in groups A and B, respectively showing no significant difference (p = 0.525). There were no cases of death due to PTC during the median follow-up of 75 months (range 36-159 months). CONCLUSIONS: Patients with locally invasive PTC with exclusive involvement of a functioning RLN may be treated by nerve shaving followed by treatment of the macroscopic residual tumor with high-dose RAI therapy.