Limits...
Targeted therapy of glioblastoma stem-like cells and tumor non-stem cells using cetuximab-conjugated iron-oxide nanoparticles.

Kaluzova M, Bouras A, Machaidze R, Hadjipanayis CG - Oncotarget (2015)

Bottom Line: Transmission electron microscopy revealed cetuximab-IONP GBM cell binding and internalization.Treatment with cetuximab-IONPs resulted in a significant antitumor effect that was greater than with cetuximab alone due to more efficient, CD133-independent cellular targeting and uptake, EGFR signaling alterations, EGFR internalization, and apoptosis induction in EGFR-expressing GSCs and neurospheres.A significant increase in survival was found after cetuximab-IONP convection-enhanced delivery treatment of 3 intracranial rodent GBM models employing human EGFR-expressing GBM xenografts.

View Article: PubMed Central - PubMed

Affiliation: Brain Tumor Nanotechnology Laboratory, Department of Neurosurgery, Emory University School of Medicine, Winship Cancer Institute of Emory University, Atlanta, GA, USA.

ABSTRACT
Malignant gliomas remain aggressive and lethal primary brain tumors in adults. The epidermal growth factor receptor (EGFR) is frequently overexpressed in the most common malignant glioma, glioblastoma (GBM), and represents an important therapeutic target. GBM stem-like cells (GSCs) present in tumors are felt to be highly tumorigenic and responsible for tumor recurrence. Multifunctional magnetic iron-oxide nanoparticles (IONPs) can be directly imaged by magnetic resonance imaging (MRI) and designed to therapeutically target cancer cells. The targeting effects of IONPs conjugated to the EGFR inhibitor, cetuximab (cetuximab-IONPs), were determined with EGFR- and EGFRvIII-expressing human GBM neurospheres and GSCs. Transmission electron microscopy revealed cetuximab-IONP GBM cell binding and internalization. Fluorescence microscopy and Prussian blue staining showed increased uptake of cetuximab-IONPs by EGFR- as well as EGFRvIII-expressing GSCs and neurospheres in comparison to cetuximab or free IONPs. Treatment with cetuximab-IONPs resulted in a significant antitumor effect that was greater than with cetuximab alone due to more efficient, CD133-independent cellular targeting and uptake, EGFR signaling alterations, EGFR internalization, and apoptosis induction in EGFR-expressing GSCs and neurospheres. A significant increase in survival was found after cetuximab-IONP convection-enhanced delivery treatment of 3 intracranial rodent GBM models employing human EGFR-expressing GBM xenografts.

No MeSH data available.


Related in: MedlinePlus

Cytotoxicity of cetuximab-IONPs in human GSCs and GBM CD133-negative cells quantified by MTT assayHuman GSCs harvested from neurospheres N08-74, N08-30 (A), and N08-1002 (B) (3×104 cells per well), GBM CD133-negative cells (3×104), and NHPC (C) were treated with free IONPs (0.2 mg/ml), cetuximab-IONPs (0.2 mg/ml), control vehicle, or cetuximab (50 μg/ml). MTT assay was performed after 24, 48, and 72 hs (GSCs and GBM CD133-negative cells) or 72 hs (NHPC). A significant decrease in cell survival was found in all human GSCs treated with the cetuximab-IONPs for 72 hs (P<0.001); cetuximab-IONPs also decreased, to a lesser degree, the survival of human GBM CD133-negative cells after 72 hs (P<0.001). No cytotoxicity was observed in NHPC cells after 72 hs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4496184&req=5

Figure 5: Cytotoxicity of cetuximab-IONPs in human GSCs and GBM CD133-negative cells quantified by MTT assayHuman GSCs harvested from neurospheres N08-74, N08-30 (A), and N08-1002 (B) (3×104 cells per well), GBM CD133-negative cells (3×104), and NHPC (C) were treated with free IONPs (0.2 mg/ml), cetuximab-IONPs (0.2 mg/ml), control vehicle, or cetuximab (50 μg/ml). MTT assay was performed after 24, 48, and 72 hs (GSCs and GBM CD133-negative cells) or 72 hs (NHPC). A significant decrease in cell survival was found in all human GSCs treated with the cetuximab-IONPs for 72 hs (P<0.001); cetuximab-IONPs also decreased, to a lesser degree, the survival of human GBM CD133-negative cells after 72 hs (P<0.001). No cytotoxicity was observed in NHPC cells after 72 hs.

Mentions: We also investigated the effect of cetuximab-IONPs on the growth of human GSCs. GSCs and GBM CD133-negative cells from N08-74, N08-30 (Figure 5A), and N08-1002 neurospheres with varying levels of EGFR expression (Figure 5B), were treated with free IONPs, cetuximab-IONPs, and cetuximab for 24, 48, and 72 hs. CD133 positivity of GSCs on the day of the experiment was verified by Western blot (data not shown). Cell proliferation and survival assays revealed that cetuximab-IONPs most efficiently decreased survival of GSCs and GBM CD133-negative cells (except N08-1002) after 72 hs (Figure 5A, B) (P<0.001). Treatment with cetuximab alone also resulted in decreased cell survival in N08-74, N08-30, and N08-1002 GSCs and in N08-74, N08-30 GBM CD133-negative cells, albeit not as efficient as with the cetuximab-IONPs (Figure 5A, B). None of the treatments affected NHPC treated for 24, 48 (data not shown), and 72 hs (Figure 5C). Increasing concentration of cetuximab to 0.2 and 0.5 mg/ml did not significantly decrease viability of N08-74 GSCs after 72 hs (data not shown). These data confirm a significant cytotoxic effect of cetuximab-IONPs on human GSCs and, to a lesser degree, on the GBM CD133-negative population of cells.


Targeted therapy of glioblastoma stem-like cells and tumor non-stem cells using cetuximab-conjugated iron-oxide nanoparticles.

Kaluzova M, Bouras A, Machaidze R, Hadjipanayis CG - Oncotarget (2015)

Cytotoxicity of cetuximab-IONPs in human GSCs and GBM CD133-negative cells quantified by MTT assayHuman GSCs harvested from neurospheres N08-74, N08-30 (A), and N08-1002 (B) (3×104 cells per well), GBM CD133-negative cells (3×104), and NHPC (C) were treated with free IONPs (0.2 mg/ml), cetuximab-IONPs (0.2 mg/ml), control vehicle, or cetuximab (50 μg/ml). MTT assay was performed after 24, 48, and 72 hs (GSCs and GBM CD133-negative cells) or 72 hs (NHPC). A significant decrease in cell survival was found in all human GSCs treated with the cetuximab-IONPs for 72 hs (P<0.001); cetuximab-IONPs also decreased, to a lesser degree, the survival of human GBM CD133-negative cells after 72 hs (P<0.001). No cytotoxicity was observed in NHPC cells after 72 hs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4496184&req=5

Figure 5: Cytotoxicity of cetuximab-IONPs in human GSCs and GBM CD133-negative cells quantified by MTT assayHuman GSCs harvested from neurospheres N08-74, N08-30 (A), and N08-1002 (B) (3×104 cells per well), GBM CD133-negative cells (3×104), and NHPC (C) were treated with free IONPs (0.2 mg/ml), cetuximab-IONPs (0.2 mg/ml), control vehicle, or cetuximab (50 μg/ml). MTT assay was performed after 24, 48, and 72 hs (GSCs and GBM CD133-negative cells) or 72 hs (NHPC). A significant decrease in cell survival was found in all human GSCs treated with the cetuximab-IONPs for 72 hs (P<0.001); cetuximab-IONPs also decreased, to a lesser degree, the survival of human GBM CD133-negative cells after 72 hs (P<0.001). No cytotoxicity was observed in NHPC cells after 72 hs.
Mentions: We also investigated the effect of cetuximab-IONPs on the growth of human GSCs. GSCs and GBM CD133-negative cells from N08-74, N08-30 (Figure 5A), and N08-1002 neurospheres with varying levels of EGFR expression (Figure 5B), were treated with free IONPs, cetuximab-IONPs, and cetuximab for 24, 48, and 72 hs. CD133 positivity of GSCs on the day of the experiment was verified by Western blot (data not shown). Cell proliferation and survival assays revealed that cetuximab-IONPs most efficiently decreased survival of GSCs and GBM CD133-negative cells (except N08-1002) after 72 hs (Figure 5A, B) (P<0.001). Treatment with cetuximab alone also resulted in decreased cell survival in N08-74, N08-30, and N08-1002 GSCs and in N08-74, N08-30 GBM CD133-negative cells, albeit not as efficient as with the cetuximab-IONPs (Figure 5A, B). None of the treatments affected NHPC treated for 24, 48 (data not shown), and 72 hs (Figure 5C). Increasing concentration of cetuximab to 0.2 and 0.5 mg/ml did not significantly decrease viability of N08-74 GSCs after 72 hs (data not shown). These data confirm a significant cytotoxic effect of cetuximab-IONPs on human GSCs and, to a lesser degree, on the GBM CD133-negative population of cells.

Bottom Line: Transmission electron microscopy revealed cetuximab-IONP GBM cell binding and internalization.Treatment with cetuximab-IONPs resulted in a significant antitumor effect that was greater than with cetuximab alone due to more efficient, CD133-independent cellular targeting and uptake, EGFR signaling alterations, EGFR internalization, and apoptosis induction in EGFR-expressing GSCs and neurospheres.A significant increase in survival was found after cetuximab-IONP convection-enhanced delivery treatment of 3 intracranial rodent GBM models employing human EGFR-expressing GBM xenografts.

View Article: PubMed Central - PubMed

Affiliation: Brain Tumor Nanotechnology Laboratory, Department of Neurosurgery, Emory University School of Medicine, Winship Cancer Institute of Emory University, Atlanta, GA, USA.

ABSTRACT
Malignant gliomas remain aggressive and lethal primary brain tumors in adults. The epidermal growth factor receptor (EGFR) is frequently overexpressed in the most common malignant glioma, glioblastoma (GBM), and represents an important therapeutic target. GBM stem-like cells (GSCs) present in tumors are felt to be highly tumorigenic and responsible for tumor recurrence. Multifunctional magnetic iron-oxide nanoparticles (IONPs) can be directly imaged by magnetic resonance imaging (MRI) and designed to therapeutically target cancer cells. The targeting effects of IONPs conjugated to the EGFR inhibitor, cetuximab (cetuximab-IONPs), were determined with EGFR- and EGFRvIII-expressing human GBM neurospheres and GSCs. Transmission electron microscopy revealed cetuximab-IONP GBM cell binding and internalization. Fluorescence microscopy and Prussian blue staining showed increased uptake of cetuximab-IONPs by EGFR- as well as EGFRvIII-expressing GSCs and neurospheres in comparison to cetuximab or free IONPs. Treatment with cetuximab-IONPs resulted in a significant antitumor effect that was greater than with cetuximab alone due to more efficient, CD133-independent cellular targeting and uptake, EGFR signaling alterations, EGFR internalization, and apoptosis induction in EGFR-expressing GSCs and neurospheres. A significant increase in survival was found after cetuximab-IONP convection-enhanced delivery treatment of 3 intracranial rodent GBM models employing human EGFR-expressing GBM xenografts.

No MeSH data available.


Related in: MedlinePlus