Smart composite scaffold to synchronize magnetic hyperthermia and chemotherapy for efficient breast cancer therapy.

Combination of different therapies is an attractive approach for cancer therapy. However, it is a challenge to synchronize different therapies for maximization of therapeutic effects. In this work, a smart composite scaffold that could synchronize magnetic hyperthermia and chemotherapy was prepared by hybridization of magnetic Fe3O4 nanoparticles and doxorubicin (Dox)-loaded thermosensitive liposomes with biodegradable polymers. Irradiation of alternating magnetic field (AMF) could not only increase the scaffold temperature for magnetic hyperthermia but also trigger the release of Dox for chemotherapy. The two functions of magnetic hyperthermia and chemotherapy were synchronized by switching AMF on and off. The synergistic anticancer effects of the composite scaffold were confirmed by in vitro cell culture and in vivo animal experiments. The composite scaffold could efficiently eliminate breast cancer cells under AMF irradiation. Moreover, the scaffold could support proliferation and adipogenic differentiation of mesenchymal stem cells for adipose tissue reconstruction after anticancer treatment. In vivo regeneration experiments showed that the composite scaffolds could effectively maintain their structural integrity and facilitate the infiltration and proliferation of normal cells within the scaffolds. The composite scaffold possesses multi-functions and is attractive as a novel platform for efficient breast cancer therapy.

Sprayable tissue adhesive microparticle-magnetic nanoparticle composites for local cancer hyperthermia.

Incomplete removal of early-stage gastrointestinal cancers by endoscopic treatments often leads to recurrence induced by residual cancer cells. To completely remove or kill cancer tissues and cells and prevent recurrence, chemotherapy, radiotherapy, and hyperthermia using biomaterials with drugs or nanomaterials are usually administered following endoscopic treatments. However, there are few biomaterials that can be applied using endoscopic devices to locally kill cancer tissues and cells. We previously reported that decyl group-modified Alaska pollock gelatin-based microparticles (denoted C10MPs) can adhere to gastrointestinal tissues under wet conditions through the formation of a colloidal gel driven by hydrophobic interactions. In this study, we combined C10MPs with superparamagnetic iron oxide nanoparticles (SPIONs) to develop a sprayable heat-generating nanomaterial (denoted SP/C10MP) for local hyperthermia of gastrointestinal cancers. The rheological property, tissue adhesion strength, burst strength, and underwater stability of SP/C10MP were improved through decyl group modification and SPION addition. Moreover, SP/C10MP that adhered to gastrointestinal tissues formed a colloidal gel, which locally generated heat in response to an alternating magnetic field. SP/C10MP successfully killed cancer tissues and cells in colon cancer-bearing mouse models in vitro and in vivo. Therefore, SP/C10MP has the potential to locally kill residual cancer tissues and cells after endoscopic treatments.

Elemental distribution analysis of type I collagen fibrils in tilapia fish scale with energy-filtered transmission electron microscope.

Elemental distribution of calcium, phosphorus, oxygen, and carbon in a single collagen fibril obtained from tilapia fish scales was identified with an electron energy-loss spectroscopy and an energy-filtered transmission electron microscopy, for the first time. The carbon intensity profile of the single collagen fibril showed the specific D-periodic pattern at 67 nm of type I collagen fibrils. The calcium L(2,3)-edge and oxygen K-edge peak positions were detected at 347/350 eV and 137 eV, respectively, and these positions were identical to those of hydroxyapatite. Calcium, phosphorus, and oxygen were present in the hole zones as the amorphous phase, while carbon was present in the overlap zone. Our results indicated that the hole zones preferentially attract calcium and phosphate ions and thus serve as possible nucleation sites for mineralization.