Iron Oxide Nanoparticle-Based Hyperthermia as a Treatment Option in Various Gastrointestinal Malignancies

Iron oxide nanoparticle-based hyperthermia is an emerging field in cancer treatment. The hyperthermia is primarily achieved by two differing methods: magnetic fluid hyperthermia and photothermal therapy. In magnetic fluid hyperthermia, the iron oxide nanoparticles are heated by an alternating magnetic field through Brownian and Néel relaxation. In photothermal therapy, the hyperthermia is mainly generated by absorption of light, thereby converting electromagnetic waves into thermal energy. By use of iron oxide nanoparticles, this effect can be enhanced. Both methods are promising tools in cancer treatment and are, therefore, also explored for gastrointestinal malignancies. Here, we provide an extensive literature research on both therapy options for the most common gastrointestinal malignancies (esophageal, gastric and colorectal cancer, colorectal liver metastases, hepatocellular carcinoma, cholangiocellular carcinoma and pancreatic cancer). As many of these rank in the top ten of cancer-related deaths, novel treatment strategies are urgently needed. This review describes the efforts undertaken in vitro and in vivo.

Magnetically guided theranostics: montmorillonite-based iron/platinum nanoparticles for enhancing in situ MRI contrast and hepatocellular carcinoma treatment

In Asia, including Taiwan, malignant tumors such as Hepatocellular carcinoma (HCC) one of the liver cancer is the most diagnosed subtype. Magnetic resonance imaging (MRI) has been a typical diagnostic method for accurately diagnosing HCC. When it is difficult to demonstrate non-enhanced MRI of tumors, radiologists can use contrast agents (such as Gd3+, Fe3O4, or FePt) for T1-weighted and T2-weighted imaging remain in the liver for a long time to facilitate diagnosis via MRI. However, it is sometimes difficult for T2-weighted imaging to detect small tumor lesions because the liver tissue may absorb iron ions. This makes early cancer detection a challenging goal. This challenge has prompted current research to create novel nanocomposites for enhancing the noise-to-signal ratio of MRI. To develop a method that can more efficiently diagnose and simultaneously treat HCC during MRI examination, we designed a functionalized montmorillonite (MMT) material with a porous structure to benefit related drugs, such as mitoxantrone (MIT) delivery or as a carrier for the FePt nanoparticles (FePt NPs) to introduce cancer therapy. Multifunctional FePt@MMT can simultaneously visualize HCC by enhancing MRI signals, treating various diseases, and being used as an inducer of magnetic fluid hyperthermia (MFH). After loading the drug MIT, FePt@MMT-MIT provides both MFH treatment and chemotherapy in one nanosystem. These results ultimately prove that functionalized FePt@MMT-MIT could be integrated as a versatile drugs delivery system by combining with MRI, chemotheraeutic drugs, and magnetic guide targeting.

Advances in Magnetic Nanoparticles Engineering for Biomedical Applications—A Review

Magnetic iron oxide nanoparticles (MNPs) have been developed and applied for a broad range of biomedical applications, such as diagnostic imaging, magnetic fluid hyperthermia, targeted drug delivery, gene therapy and tissue repair. As one key element, reproducible synthesis routes of MNPs are capable of controlling and adjusting structure, size, shape and magnetic properties are mandatory. In this review, we discuss advanced methods for engineering and utilizing MNPs, such as continuous synthesis approaches using microtechnologies and the biosynthesis of magnetosomes, biotechnological synthesized iron oxide nanoparticles from bacteria. We compare the technologies and resulting MNPs with conventional synthetic routes. Prominent biomedical applications of the MNPs such as diagnostic imaging, magnetic fluid hyperthermia, targeted drug delivery and magnetic actuation in micro/nanorobots will be presented.

Magnetically Guided Theranostics: Enhancing the Contrast of Magnetic Resonance Imaging With Multiple-Layer Montmorillonite-Based Iron/Platinum Nanoparticles for the Treatment of Orthotopic Hepatocellular Carcinoma

In Asia, including Taiwan, malignant tumors such as Hepatocellular carcinoma (HCC) one of the liver cancer is the most diagnosed subtype. Magnetic resonance imaging (MRI) has been a typical diagnostic method for accurately diagnosing HCC. When it is difficult to demonstrate non-enhanced MRI of tumors, radiologists can use contrast agents (such as Gd3+, Fe3O4, or FePt) for T1-weighted and T2-weighted imaging, which can remain in the liver for a long time to facilitate diagnosis via MRI. However, sometimes it is difficult for T2-weighted imaging to detect small tumor lesions because the liver tissue may actively absorb iron ions. This makes early cancer detection a challenging goal. To develop a method that can more efficiently diagnose and simultaneously treat HCC during MRI examination, we designed a functionalized montmorillonite (MMT) material with a porous structure to benefit related drugs, such as mitoxantrone (MIT) delivery or as a carrier for the FePt nanoparticles (FePt NPs) to introduce cancer therapy. Multifunctional FePt@MMT can simultaneously visualize and treat various diseases and can be used as an inducer of magnetic fluid hyperthermia (MFH). After loading the drug MIT, FePt@MMT-MIT provides both MFH treatment and chemotherapy in one nanosystem. These results ultimately prove that functionalized FePt@MMT-MIT could be integrated as a versatile drugs delivery system by combining with MRI, chemotherapeutic drugs, and magnetic guide targeting.

Analysis of field free region formed by parametric positioning of a magnet pair for targeted magnetic hyperthermia

One of the challenges that arise in the practical applications of magnetic fluid hyperthermia (MFH) is the limited control of magnetic nanoparticle oscillations. In this study, we investigated to manipulate field free region (FFR) form and location by symmetric and asymmetric displacements of a magnet pair (MP). Finite element method (FEM) simulation was used to predict gradient patterns (GPs) in the workspace. An experiment platform was produced and point probe measurements are taken. It is observed that FFR form and position can be manipulated with parametric distance and angle changes. FFR can shrink and its form can be transformed to the linelike or point-like areas. Focus of FFR can be moved off-center, and it can be directed to different parts of the target object. The mapping of GP produced by a MP for the use of targeted MFH is discussed for the first time in this study. And the findings provide insight into which GP is appropriate in which situations in targeted MFH.

Investigating the effect of outer layer of magnetic particles on cervical cancer cells HeLa by magnetic fluid hyperthermia

Background Magnetic fluid hyperthermia (MFH) is a successful nanotechnology application in recent decade where a biocompatible magnetic fluid is used to kill cancer cells in a controlled heating using AC magnetic field. In the present study, two ferrite-based magnetic fluids, with and without surfactant coating, were synthesized to study the effect of the outer layer of magnetic nanoparticles on cervical cancer cells. The magnetic fluid without surfactant coating (MFWI) was made stable by providing negative charge on the surface of each particle. On the other hand, lauric acid was used as a surfactant to have a stable dispersion of particles in aqueous media (MFWL). Methods The structural, magnetic properties and induction heating response of both the fluids were investigated using XRD, VSM, DLS, TGA, FTIR, and a high-frequency induction heater. The in vitro cytotoxicity of the synthesized fluids was observed on HeLa cells by performing MTT assay, and the effect of magnetic fluid hyperthermia was examined using Trypan blue assay. Results The crystallite size of surfactant stabilized particles was higher (11.0 ± 0.5 nm) compared to the charge stabilized particles (8.3 ± 0.5 nm). Induction heating experiments showed that the specific absorption rate of the surfactant-coated particles was almost double compared to ionic particle fluid. Magnetic fluid hyperthermia up to 1 hour at a concentration of 0.25 mg/mL of surfactant-coated magnetic fluid and 0.2 mg/mL concentration of charged fluid resulted in approximately 66 and 80% cell death, respectively, compared to untreated control cells. Conclusion The preliminary analysis of this study shows significant cell death due to hyperthermia, wherein MFWI revealed higher cytotoxicity compared to MFWL. Additional analysis into the role of the outer stabilizing layer on nanoparticle’s surface, concentration of nanoparticles, and hyperthermic duration is desirable to utilize MFH as a futuristic anti-cancer therapeutic tool.