PMMA-Fe₃O₄ for internal mechanical support and magnetic thermal ablation of bone tumors

Abstract

Background : Minimally invasive modalities are of great interest in the field of treating bone tumors. However, providing reliable mechanical support and fast killing of tumor cells to achieve rapid recovery of physical function is still challenging in clinical works. Methods : A material with two functions, mechanical support and magnetic thermal ablation, was developed from Fe 3 O 4 nanoparticles (NPs) distributed in a polymethylmethacrylate (PMMA) bone cement. The mechanical properties and efficiency of magnetic field-induced thermal ablation were systematically and successfully evaluated in vitro and ex vivo . CT images and pathological examination were successfully applied to evaluate therapeutic efficacy with a rabbit bone tumor model. Biosafety evaluation was performed with a rabbit in vivo , and a cytotoxicity test was performed in vitro . Results : An NP content of 6% Fe 3 O 4 (PMMA-6% Fe 3 O 4 , m Fe : 0.01 g) gave the most suitable performance for in vivo study. At the 56-day follow-up after treatment, bone tumors were ablated without obvious side effects. The pathological examination and new bone formation in CT images clearly illustrate that the bone tumors were completely eliminated. Correspondingly, after treatment, the tendency of bone tumors toward metastasis significantly decreased. Moreover, with well-designed mechanical properties, PMMA-6%Fe 3 O 4 implantation endowed tumor-bearing rabbit legs with excellent bio-mimic bone structure and internal support. Biosafety evaluation did not induce an increase or decrease in the immune response, and major functional parameters were all at normal levels. Conclusion : We have presented a novel, highly efficient and minimally invasive approach for complete bone tumor regression and bone defect repair by magnetic thermal ablation based on PMMA containing Fe 3 O 4 NPs; this approach shows excellent heating ability for rabbit VX2 tibial plateau tumor ablation upon exposure to an alternating magnetic field (AMF) and provides mechanical support for bone repair. The new and powerful dual-function implant is a promising minimally invasive agent for the treatment of bone tumors and has good clinical translation potential.

Zwitterionic Polymer-Gated Au@TiO2 Core-Shell Nanoparticles for Imaging-Guided Combined Cancer Therapy

“…It was speculated that P(CitAPDMAEMA)@Au@TiO 2 NPs were captured by the liver, spleen, and lung tissues, which prolonged the blood-circulation lifetime. As a result, this progress increased the efficiency of the P(CitAPDMAEMA)@Au@TiO 2 @DOX NPs to recognize and gather at the tumor site 49. In particular, the gathering of P(CitAPDMAEMA)@Au@TiO 2 @DOX NPs in the heart decreased, indicating that the nanosystem could decrease cardiac muscle toxicity caused by DOX.…”

Recent Advances of Magnetic Nanomaterials in Bone Tissue Repair

“…The magnetic field has been proven to enhance bone tissue repair by affecting cell metabolic behavior (Iwasa and Reddi, 2018 ; He et al, 2019 ; Liu H. Y. et al, 2020 ). In recent research, iron is the most common material used with its para-magnetism (Luo et al, 2018 ; Xia et al, 2018 ; Yu et al, 2019 ). The unpaired electrons of the outermost layer spin to make the atom maintain a certain magnetic moment.…”

“…In the absence of a magnetic field, the atomic magnetic moments are also neatly arranged, showing strong magnetism to the outside (Luo et al, 2018 ; Xia et al, 2018 ; He et al, 2019 ). Containing a small amount of paramagnetic iron, the bone is magnetically conductive (Luo et al, 2018 ; Xia et al, 2018 ; Yu et al, 2019 ).…”

The minimally invasive endoscopic technique for the treatment of symptomatic benign bone lesions: Preliminary results from a retrospective study

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