In vitrophotothermal destruction of neuroblastoma cells using carbon nanotubes conjugated with GD2 monoclonal antibody

Abstract

Despite aggressive multimodality therapy, most neuroblastoma-bearing patients relapse and survival rate remains poor. Exploration of alternative therapeutic modalities is needed. Carbon nanotubes (CNTs), revealing optical absorbance in the near-infrared region, warrant their merits in photothermal therapy. In order to specifically target disialoganglioside (GD2) overexpressed on the surface of neuroblastoma stNB-V1 cells, GD2 monoclonal antibody (anti-GD2) was conjugated to acidified CNTs. To examine the fate of anti-GD2 bound CNTs after incubation with stNB-V1 cells, rhodamine B was labeled on carboxylated CNTs functionalized with and without anti-GD2. Our results illustrated that anti-GD2-linked CNTs were extensively internalized by neuroblastoma cells via GD2-mediated endocytosis. In addition, we showed that anti-GD2 bound CNTs were not ingested by PC12 cells without GD2 expression. After anti-GD2 conjugated CNTs were incubated with neuroblastoma cells for 6 h and endocytosed by the cells, CNT-laden neuroblastoma cells were further irradiated with an 808 nm near-infrared (NIR) laser with intensity ramping from 0.6 to 6 W cm(-2) for 10 min which was then maintained at 6 W cm(-2) for an additional 5 min. Post-NIR laser exposure, and after being examined by calcein-AM dye, stNB-V1 cells were all found to undergo necrosis, while non-GD2 expressing PC12 cells all remained viable. Based on the in vitro study, CNTs bound with anti-GD2 have the potential to be utilized as a therapeutic thermal coupling agent that generates heat sufficient to selectively kill neuroblastoma cells under NIR laser light exposure.

Carbon nanotubes as cancer therapeutic carriers and mediators

“…120 This unique property of CNTs has been exploited as a method for killing cancer cells via thermal effects. [121][122][123][124][125][126][127][128][129][130][131][132][133][134] The optical coupling of light with CNTs can be enhanced by the surface defects of CNTs based on the antenna theory, and nanotechnology induces intentional surface defects to increase nanotube heating. 122 This electrophysical characteristic of the engineered CNTs including boron and nitrogen dopants (p-type dopants) to improve the thermal destruction performance of tumor cells.…”

“…Wang et al 126 conjugated disialoganglioside (GD2) monoclonal antibody (anti-GD2) to acidified MWCNTs to target GD2 overexpressed on the surface of neuroblastoma stNB-V1 cells. To track the anti-GD2-bound MWCNTs, rhodamine B was labeled on carboxylated CNTs functionalized with and without anti-GD2.…”

Anti-GD2 MABS and Next-Generation mAb-Based Agents for Cancer Therapy

“…Different nanoparticle formats that have been bioconjugated with anti-GD2 full size mAbs or Fab fragments include: liposomes, which have small diameter and are able to differentially accumulate and penetrate into solid tumors (with highly permeable capillaries) relative to normal tissue (with less permeable tight junctions) [121][122][123][124]; porous silica nanoparticles, which are inert, biodegradable, nontoxic and more stable due to uniform particle size [125]; gold nanorods and carbon nanotubes capable of absorbing near-infrared laser light leading to in vitro photothermal destruction of tumor cells [126,127]. ; and iron-based nanoparticles that enable direct delivery of drugs c arried by the nanoparticle [128].…”

Advances in cancer therapy through the use of carbon nanotube-mediated targeted hyperthermia

“…35 It has been stated that a proficient method needed to minimize toxic effects and also to increase the level of therapeutic response for CNTs, is represented by their conjugation to a carrier molecule. 25,[35][36][37][38][39][40][41][42] For instance, various strategies for the fabrication of nanomoieties to target folate receptors on the cancer cell membrane have been proposed. 12 Folate receptors are overexpressed in cancer and their targeting allows CNTs to facilitate cellular internalization of folatecontaining species by receptor-mediated endocytosis 43 which is more selective than CNTs alone that enter cells through phagocytosis or endocytosis and through passive diffusion.…”

“…41 After the treatment of neuroblastoma cells with anti-GD2 conjugated CNTs for 6 hours, the cells were further irradiated with an 808 nm NIR laser with intensity increasing from 0.6 to 6 W/cm 2 for 10 minutes which was then maintained at 6 W/cm 2 for an additional 5 minutes. Post-NIR laser exposure and after being examined by calcein-AM dye, stNB-V1 cells were all foud to be necrotic, while non-GD2 expressing PC12 cells (control) remained viable.…”