School of Bioscience and Biotechnology, Chubu University, Aichi, Japan.
Biotechnol J. 2011 Nov;6(11):1342-7. doi: 10.1002/biot.201100045. Epub 2011 Aug 26.
Magnetic-nanoparticle-mediated intracellular hyperthermia has the potential to achieve localized tumor heating without any side effects. The technique consists of targeting magnetic nanoparticles to tumor tissue followed by application of an external alternating magnetic field that induces heat through Néel relaxation loss of the magnetic nanoparticles. The temperature in tumor tissue is increased to above 43°C, which causes necrosis of cancer cells, but does not damage surrounding normal tissue. Among magnetic nanoparticles available, magnetite has been extensively studied. Recent years have seen remarkable advances in magnetite-nanoparticle-mediated hyperthermia; both functional magnetite nanoparticles and alternating-magnetic-field generators have been developed. In addition to the expected tumor cell death, hyperthermia treatment has also induced unexpected biological responses, such as tumor-specific immune responses as a result of heat-shock protein expression. These results suggest that hyperthermia is able to kill not only local tumors exposed to heat treatment, but also tumors at distant sites, including metastatic cancer cells. Currently, several research centers have begun clinical trials with promising results, suggesting that the time may have come for clinical applications. This review describes recent advances in magnetite nanoparticle-mediated hyperthermia.
磁纳米粒子介导的细胞内热疗有可能实现肿瘤局部加热而无任何副作用。该技术包括将磁性纳米粒子靶向肿瘤组织，然后施加外部交变磁场，通过磁性纳米粒子的奈尔弛豫损耗来产生热量。肿瘤组织中的温度升高到 43°C 以上，导致癌细胞坏死，但不会损伤周围正常组织。在可用的磁性纳米粒子中，磁铁矿已经得到了广泛的研究。近年来，磁铁矿纳米粒子介导的热疗取得了显著进展；功能性磁铁矿纳米粒子和交变磁场发生器都得到了发展。除了预期的肿瘤细胞死亡外，热疗还诱导了意想不到的生物学反应，如由于热休克蛋白表达而引起的肿瘤特异性免疫反应。这些结果表明，热疗不仅能够杀死暴露于热疗的局部肿瘤，还能够杀死远处的肿瘤，包括转移性癌细胞。目前，几个研究中心已经开始了临床试验，并取得了有希望的结果，这表明临床应用的时机可能已经到来。本文综述了磁纳米粒子介导的热疗的最新进展。
