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A Hybrid Nanomaterial for the Controlled Generation of Free Radicals and Oxidative Destruction of Hypoxic Cancer Cells.

ABSTRACT: Anticancer modalities based on oxygen free radicals, including photodynamic therapy and radiotherapy, have emerged as promising treatments in the clinic. However, the hypoxic environment in tumor tissue prevents the formation of oxygen free radicals. Here we introduce a novel strategy that employs oxygen-independent free radicals generated from a polymerization initiator for eradicating cancer cells. The initiator is mixed with a phase-change material and loaded into the cavities of gold nanocages. Upon irradiation by a near-infrared laser, the phase-change material is melted due to the photothermal effect of gold nanocages, leading to the release and decomposition of the loaded initiator to generate free radicals. The free radicals produced in this way are highly effective in inducing apoptosis in hypoxic cancer cells.

SUBMITTER: Shen S

PROVIDER: S-EPMC5543408 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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A Hybrid Nanomaterial for the Controlled Generation of Free Radicals and Oxidative Destruction of Hypoxic Cancer Cells.

Shen Song S Zhu Chunlei C Huo Da D Yang Miaoxin M Xue Jiajia J Xia Younan Y

Angewandte Chemie (International ed. in English) 20170502 30

Anticancer modalities based on oxygen free radicals, including photodynamic therapy and radiotherapy, have emerged as promising treatments in the clinic. However, the hypoxic environment in tumor tissue prevents the formation of oxygen free radicals. Here we introduce a novel strategy that employs oxygen-independent free radicals generated from a polymerization initiator for eradicating cancer cells. The initiator is mixed with a phase-change material and loaded into the cavities of gold nanocag ...[more]

PMID: 28464414

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