Limits...
Enhancement of radiotherapy by ceria nanoparticles modified with neogambogic acid in breast cancer cells.

Chen F, Zhang XH, Hu XD, Zhang W, Lou ZC, Xie LH, Liu PD, Zhang HQ - Int J Nanomedicine (2015)

Bottom Line: NGA-CNPs potentiated the toxic effects of radiation, leading to a higher rate of cell death than either treatment used alone and inducing the activation of autophagy and cell cycle arrest at the G2/M phase, while pretreatment with NGA or CNPs did not improve the rate of radiation-induced cancer cells death.However, NGA-CNPs decreased both endogenous and radiation-induced reactive oxygen species formation, unlike other nanomaterials.These results suggest that the adjunctive use of NGA-CNPs can increase the effectiveness of radiotherapy in breast cancer treatment by lowering the radiation doses required to kill cancer cells and thereby minimizing collateral damage to healthy adjacent tissue.

View Article: PubMed Central - PubMed

Affiliation: College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China.

ABSTRACT
Radiotherapy is one of the main strategies for cancer treatment but has significant challenges, such as cancer cell resistance and radiation damage to normal tissue. Radiosensitizers that selectively increase the susceptibility of cancer cells to radiation can enhance the effectiveness of radiotherapy. We report here the development of a novel radiosensitizer consisting of monodispersed ceria nanoparticles (CNPs) covered with the anticancer drug neogambogic acid (NGA-CNPs). These were used in conjunction with radiation in MCF-7 breast cancer cells, and the efficacy and mechanisms of action of this combined treatment approach were evaluated. NGA-CNPs potentiated the toxic effects of radiation, leading to a higher rate of cell death than either treatment used alone and inducing the activation of autophagy and cell cycle arrest at the G2/M phase, while pretreatment with NGA or CNPs did not improve the rate of radiation-induced cancer cells death. However, NGA-CNPs decreased both endogenous and radiation-induced reactive oxygen species formation, unlike other nanomaterials. These results suggest that the adjunctive use of NGA-CNPs can increase the effectiveness of radiotherapy in breast cancer treatment by lowering the radiation doses required to kill cancer cells and thereby minimizing collateral damage to healthy adjacent tissue.

No MeSH data available.


Related in: MedlinePlus

FTIR and XPS analysis of NGA-CNPs.Notes: (A) FTIR spectrum of CNPs before and after modification with epichlorohydrin. Absorption at 1,100 cm−1 and 1,650 cm−1 corresponding to hydroxide and amine groups, respectively, was observed for amine-functionalized CNPs (NH2-CNP; red line) relative to unmodified CNPs (black line). (B) XPS spectrum of functionalized CNPs. Numbers represent positions of peaks.Abbreviations: FTIR, Fourier transform infrared spectroscopy; XPS, X-ray photoelectron spectroscopy; NGA-CNP, ceria nanoparticle modified with neogambogic acid; CNP, ceria nanoparticle; au, arbitrary unit.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4542556&req=5

f3-ijn-10-4957: FTIR and XPS analysis of NGA-CNPs.Notes: (A) FTIR spectrum of CNPs before and after modification with epichlorohydrin. Absorption at 1,100 cm−1 and 1,650 cm−1 corresponding to hydroxide and amine groups, respectively, was observed for amine-functionalized CNPs (NH2-CNP; red line) relative to unmodified CNPs (black line). (B) XPS spectrum of functionalized CNPs. Numbers represent positions of peaks.Abbreviations: FTIR, Fourier transform infrared spectroscopy; XPS, X-ray photoelectron spectroscopy; NGA-CNP, ceria nanoparticle modified with neogambogic acid; CNP, ceria nanoparticle; au, arbitrary unit.

Mentions: The structure of NGA and steps in the synthesis of the CNPs are shown in Figure 2. NGA was conjugated by first attaching epichlorohydrin to the NP surface via a standard SN2 reaction, in which the oxygen atom of the NP replaced the chlorine atom of epichlorohydrin, creating an oxygen bond between the NP and the carbon of epichlorohydrin. Next, ammonia was used to open up the epoxide ring of epichlorohydrin to yield hydroxyl (−OH) and amine (−NH2) groups available for additional reactions. The FTIR spectrum confirmed amine functionalization (Figure 3A).


Enhancement of radiotherapy by ceria nanoparticles modified with neogambogic acid in breast cancer cells.

Chen F, Zhang XH, Hu XD, Zhang W, Lou ZC, Xie LH, Liu PD, Zhang HQ - Int J Nanomedicine (2015)

FTIR and XPS analysis of NGA-CNPs.Notes: (A) FTIR spectrum of CNPs before and after modification with epichlorohydrin. Absorption at 1,100 cm−1 and 1,650 cm−1 corresponding to hydroxide and amine groups, respectively, was observed for amine-functionalized CNPs (NH2-CNP; red line) relative to unmodified CNPs (black line). (B) XPS spectrum of functionalized CNPs. Numbers represent positions of peaks.Abbreviations: FTIR, Fourier transform infrared spectroscopy; XPS, X-ray photoelectron spectroscopy; NGA-CNP, ceria nanoparticle modified with neogambogic acid; CNP, ceria nanoparticle; au, arbitrary unit.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4542556&req=5

f3-ijn-10-4957: FTIR and XPS analysis of NGA-CNPs.Notes: (A) FTIR spectrum of CNPs before and after modification with epichlorohydrin. Absorption at 1,100 cm−1 and 1,650 cm−1 corresponding to hydroxide and amine groups, respectively, was observed for amine-functionalized CNPs (NH2-CNP; red line) relative to unmodified CNPs (black line). (B) XPS spectrum of functionalized CNPs. Numbers represent positions of peaks.Abbreviations: FTIR, Fourier transform infrared spectroscopy; XPS, X-ray photoelectron spectroscopy; NGA-CNP, ceria nanoparticle modified with neogambogic acid; CNP, ceria nanoparticle; au, arbitrary unit.
Mentions: The structure of NGA and steps in the synthesis of the CNPs are shown in Figure 2. NGA was conjugated by first attaching epichlorohydrin to the NP surface via a standard SN2 reaction, in which the oxygen atom of the NP replaced the chlorine atom of epichlorohydrin, creating an oxygen bond between the NP and the carbon of epichlorohydrin. Next, ammonia was used to open up the epoxide ring of epichlorohydrin to yield hydroxyl (−OH) and amine (−NH2) groups available for additional reactions. The FTIR spectrum confirmed amine functionalization (Figure 3A).

Bottom Line: NGA-CNPs potentiated the toxic effects of radiation, leading to a higher rate of cell death than either treatment used alone and inducing the activation of autophagy and cell cycle arrest at the G2/M phase, while pretreatment with NGA or CNPs did not improve the rate of radiation-induced cancer cells death.However, NGA-CNPs decreased both endogenous and radiation-induced reactive oxygen species formation, unlike other nanomaterials.These results suggest that the adjunctive use of NGA-CNPs can increase the effectiveness of radiotherapy in breast cancer treatment by lowering the radiation doses required to kill cancer cells and thereby minimizing collateral damage to healthy adjacent tissue.

View Article: PubMed Central - PubMed

Affiliation: College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, People's Republic of China.

ABSTRACT
Radiotherapy is one of the main strategies for cancer treatment but has significant challenges, such as cancer cell resistance and radiation damage to normal tissue. Radiosensitizers that selectively increase the susceptibility of cancer cells to radiation can enhance the effectiveness of radiotherapy. We report here the development of a novel radiosensitizer consisting of monodispersed ceria nanoparticles (CNPs) covered with the anticancer drug neogambogic acid (NGA-CNPs). These were used in conjunction with radiation in MCF-7 breast cancer cells, and the efficacy and mechanisms of action of this combined treatment approach were evaluated. NGA-CNPs potentiated the toxic effects of radiation, leading to a higher rate of cell death than either treatment used alone and inducing the activation of autophagy and cell cycle arrest at the G2/M phase, while pretreatment with NGA or CNPs did not improve the rate of radiation-induced cancer cells death. However, NGA-CNPs decreased both endogenous and radiation-induced reactive oxygen species formation, unlike other nanomaterials. These results suggest that the adjunctive use of NGA-CNPs can increase the effectiveness of radiotherapy in breast cancer treatment by lowering the radiation doses required to kill cancer cells and thereby minimizing collateral damage to healthy adjacent tissue.

No MeSH data available.


Related in: MedlinePlus