Strategies to Improve Cancer Photothermal Therapy Mediated by Nanomaterials

Abstract

The deployment of hyperthermia-based treatments for cancer therapy has captured the attention of different researchers worldwide. In particular, the application of light-responsive nanomaterials to mediate hyperthermia has revealed promising results in several pre-clinical assays. Unlike conventional therapies, these nanostructures can display a preferential tumor accumulation and thus mediate, upon irradiation with near-infrared light, a selective hyperthermic effect with temporal resolution. Different types of nanomaterials such as those based on gold, carbon, copper, molybdenum, tungsten, iron, palladium and conjugated polymers have been used for this photothermal modality. This progress report summarizes the different strategies that have been applied so far for increasing the efficacy of the photothermal therapeutic effect mediated by nanomaterials, namely those that improve the accumulation of nanomaterials in tumors (e.g. by changing the corona composition or through the functionalization with targeting ligands), increase nanomaterials' intrinsic capacity to generate photoinduced heat (e.g. by synthesizing new nanomaterials or assembling nanostructures) or by optimizing the parameters related to the laser light used in the irradiation process (e.g. by modulating the radiation wavelength). Overall, the development of new strategies or the optimization and combination of the existing ones will surely give a major contribution for the application of nanomaterials in cancer PTT.

Self‐Assembled/Drug‐Composed Nanomedicine for Synergistic Photonic Hyperthermia and Targeted Therapy of Breast Cancer by Inhibiting ERK, AKT, and STAT3 Signaling Cascades

“…At present, because of the unique superiorities of high specificity as well as minimal invasiveness, photothermal therapy (PTT) has become a promising strategy in treating cancer superior to chemotherapy to some extent . Recently, near‐infrared (NIR) fluorescent dye, like IR820 has also attracted tremendous interest in phototherapy due to their strong photonic absorbance in NIR wavelength range (700–900 nm) and high ability to convert the absorbed NIR optical energy into thermo energy, which can be justified by that the temperature of tissue reaches 55–95 °C within a few minutes when exposed to NIR in the presence of NIR agent . Moreover, most NIR dyes are nontoxic .…”

The True Complexity of Photothermal Therapy: A Brief Perspective

“…Many of the aforementioned techniques have being tested in vivo, revealing promising results and a low toxicity profile. However, despite all these efforts, only a few designs have reached pre-clinical trials, and their true therapeutic capability is yet to be revealed [1]. In summary, this promising therapy, despite its potential and very many applications in health, still requires a great deal of fundamental research to address certain issues that are still not fully understood.…”

“…Among all those materials used, by far the most popular is gold, thanks to its straightforward synthesis, ease of functionalization, optical properties and low toxicity [3,5]. Carbon-based nanomaterials also represent a strong branch of research thanks to its structural versatility, allowing to create configurations with unique optical properties such as carbon nanotubes and nanographene oxide [1], among others [5]. In addition, there have been many attempts of alternative approaches by combining PTT with other techniques like drug delivery [3,6,7], photodynamic therapy [3,8], optoacoustic imaging [9,10] and immunotherapy [11] among others.…”

“…Combined with nanoparticles, it represents a relatively novel and attractive tool that has grabbed the attention of both researchers and clinicians [1,2]. It consists of the use of nanoparticles with the ultimate goal to specifically localize in the diseased area, which upon illumination with a laser are able to convert the incoming light into heat which ultimately induce cell death of the affected area [3], similar to a nanometric scalpel.…”

“…Various types of starting materials have being used in order to synthesize the nanoparticles: gold, carbon, copper, molybdenum, tungsten, iron, palladium and conjugated polymers [1], both individually or combined. Among all those materials used, by far the most popular is gold, thanks to its straightforward synthesis, ease of functionalization, optical properties and low toxicity [3,5].…”