Holmium-containing bioactive glasses can be applied in bone cancer treatment because the holmium content can be neutron activated, having suitable properties for brachytherapy applications, while the bioactive glass matrix can regenerate the bone alterations induced by the tumor. To facilitate the application of these glasses in clinical practice, we proposed a composite based on Poloxamer 407 thermoresponsive hydrogel, with suitable properties for applications as injectable systems. Therefore, in this work, we evaluated the influence of holmium-containing glass particles on the properties of Poloxamer 407 hydrogel (20 w/w.%), including self-assembly ability and biological properties. 58S bioactive glasses (58SiO₂-33CaO-9P₂O₅) containing different Ho₂O₃ amounts (1.25, 2.5, 3.75, and 5 wt.%) were incorporated into the hydrogel. The formulations were characterized by scanning electron microscopy, differential scanning calorimetry, rheological tests, and [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] MTT cell viability against pre-osteoblastic and osteosarcoma cells. The results evidenced that neither the glass particles dispersed in the hydrogel nor the holmium content in the glasses significantly influenced the hydrogel self-assembly ability (T_mic ~13.8 °C and T_gel ~20 °C). Although, the glass particles considerably diminished the hydrogel viscosity in one order of magnitude at body temperature (37 °C). The cytotoxicity results evidenced that the formulations selectively favored pre-osteoblastic cell proliferation and osteosarcoma cell death. In conclusion, the formulation containing glass with the highest fraction of holmium content (5 wt.%) had the best biological results outcomes aiming its application as theragenerative materials for bone cancer treatment.

Traditional cancer treatments, such as surgery, radiotherapy, and chemotherapy, are still the most effective clinical practice options. However, these treatments may display moderate to severe side effects caused by their low temporal or spatial resolution. In this sense, photonic nanomedicine therapies have been arising as an alternative to traditional cancer treatments since they display more control of temporal and spatial resolution, thereby yielding fewer side effects. In this work, we reviewed the challenge of current cancer treatments, using the PubMed and Web of Science database, focusing on the advances of three prominent therapies approached by photonic nanomedicine: (i) photothermal therapy; (ii) photodynamic therapy; (iii) photoresponsive drug delivery systems. These photonic nanomedicines act on the cancer cells through different mechanisms, such as hyperthermic effect and delivery of chemotherapeutics and species that cause oxidative stress. Furthermore, we covered the recent advances in materials science applied in photonic nanomedicine, highlighting the main classes of materials used in each therapy, their applications in the context of cancer treatment, as well as their advantages, limitations, and future perspectives. Finally, although some photonic nanomedicines are undergoing clinical trials, their effectiveness in cancer treatment have already been highlighted by pre-clinical studies.

The fight against cancer is an old challenge for mankind. Apart from surgery and chemotherapy, which are the most common treatments, use of radiation represents a promising, less invasive strategy that can be performed both from the outside or inside the body. The latter approach, also known as brachytherapy, relies on the use of implantable beta-emitting seeds or microspheres for killing cancer cells. A set of radioactive glasses have been developed for this purpose but their clinical use is still mainly limited to liver cancer. This review paper provides a picture of the biomedical glasses developed and experimented for brachytherapy so far, focusing the discussion on the production methods and current limitations of the available options to their diffusion in clinical practice. Highly-durable neutron-activatable glasses in the yttria-alumina-silica oxide system are typically preferred in order to avoid the potentially-dangerous release of radioisotopes, while the compositional design of degradable glass systems suitable for use in radiotherapy still remains a challenge and would deserve further investigation in the near future.