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Magnetic resonance-guided regional gene delivery strategy using a tumor stroma-permeable nanocarrier for pancreatic cancer.

Wang Q, Li J, An S, Chen Y, Jiang C, Wang X - Int J Nanomedicine (2015)

Bottom Line: Third-generation dendrigraft poly-L-lysines was selected as the nanocarrier scaffold, which was modified by cell-penetrating peptides and gadolinium (Gd) chelates.Permeability of the nanoparticles modified by cell-penetrating peptides was superior to that of the unmodified counterpart, demonstrating the improved capability of nanoparticles for diffusion in tumor stroma on magnetic resonance imaging.This study demonstrated that an image-guided gene delivery system with a stroma-permeable gene vector could be a potential clinically translatable gene therapy strategy for PDAC.

View Article: PubMed Central - PubMed

Affiliation: Department of Interventional Radiology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China ; Shanghai Institute of Medical Imaging, Fudan University, Shanghai, People's Republic of China.

ABSTRACT

Background: Gene therapy is a very promising technology for treatment of pancreatic ductal adenocarcinoma (PDAC). However, its application has been limited by the abundant stromal response in the tumor microenvironment. The aim of this study was to prepare a dendrimer-based gene-free loading vector with high permeability in the tumor stroma and explore an imaging-guided local gene delivery strategy for PDAC to promote the efficiency of targeted gene delivery.

Methods: The experimental protocol was approved by the animal ethics committee of Zhongshan Hospital, Fudan University. Third-generation dendrigraft poly-L-lysines was selected as the nanocarrier scaffold, which was modified by cell-penetrating peptides and gadolinium (Gd) chelates. DNA plasmids were loaded with these nanocarriers via electrostatic interaction. The cellular uptake and loaded gene expression were examined in MIA PaCa-2 cell lines in vitro. Permeability of the nanoparticles in the tumor stroma and transfected gene distribution in vivo were studied using a magnetic resonance imaging-guided delivery strategy in an orthotopic nude mouse model of PDAC.

Results: The nanocarriers were synthesized with a dendrigraft poly-L-lysine to polyethylene glycol to DTPA ratio of 1:3.4:8.3 and a mean diameter of 110.9±7.7 nm. The luciferases were strictly expressed in the tumor, and the luminescence intensity in mice treated by Gd-DPT/plasmid luciferase (1.04×10(4)±9.75×10(2) p/s/cm(2)/sr) was significantly (P<0.05) higher than in those treated with Gd-DTPA (9.56×10(2)±6.15×10 p/s/cm(2)/sr) and Gd-DP (5.75×10(3)± 7.45×10(2) p/s/cm(2)/sr). Permeability of the nanoparticles modified by cell-penetrating peptides was superior to that of the unmodified counterpart, demonstrating the improved capability of nanoparticles for diffusion in tumor stroma on magnetic resonance imaging.

Conclusion: This study demonstrated that an image-guided gene delivery system with a stroma-permeable gene vector could be a potential clinically translatable gene therapy strategy for PDAC.

No MeSH data available.


Related in: MedlinePlus

Confocal luminescence microscopy showing the in vivo distribution and amount of RFP expressed after transfection by naked plasmid or nanoparticles. Upper panel shows Gd-DTPA/pRFP (Gd-DTPA), middle panel shows Gd-DP/pRFP (Gd-DP), and lower panel shows Gd-DPT/pRFP (Gd-DPT). Red indicates RFP, blue indicates DAPI-stained cell nuclei, and yellow lines indicate crevices in tumor tissue. Original magnification 200×.Abbreviations: Gd, gadolinium; DAPI, 4,6-diamidino-2-phenylindole; pRFP, plasmid red fluorescence protein; DGL, dendrigraft poly-L-lysine; PEG, polyethylene glycol; DTPA, gadopentetate dimeglumine; DP, DTPA-DGL-PEG; DPT, DTPA-DGL-PEG-TAT.
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f6-ijn-10-4479: Confocal luminescence microscopy showing the in vivo distribution and amount of RFP expressed after transfection by naked plasmid or nanoparticles. Upper panel shows Gd-DTPA/pRFP (Gd-DTPA), middle panel shows Gd-DP/pRFP (Gd-DP), and lower panel shows Gd-DPT/pRFP (Gd-DPT). Red indicates RFP, blue indicates DAPI-stained cell nuclei, and yellow lines indicate crevices in tumor tissue. Original magnification 200×.Abbreviations: Gd, gadolinium; DAPI, 4,6-diamidino-2-phenylindole; pRFP, plasmid red fluorescence protein; DGL, dendrigraft poly-L-lysine; PEG, polyethylene glycol; DTPA, gadopentetate dimeglumine; DP, DTPA-DGL-PEG; DPT, DTPA-DGL-PEG-TAT.

Mentions: A few cells with a weak luminescence signal in the tumors treated with the Gd-DTPA and pRFP complexes were detected using confocal luminescence microscopy, indicating that there was limited gene transfer when injecting naked plasmid (upper panel, Figure 6). The pRFP loaded by Gd-DP was better translated in a single cancer cell compared with Gd-DTPA/pRFP, demonstrating that dendrimers could protect the plasmid from being degraded in the lysosome24 (middle panel, Figure 6). Additionally, for both of the above groups, the transfected cells settled along crevices in the tumor tissue. However, expression of RFP in cells treated with Gd-DPT/pRFP was homogeneous in its distribution and had a strong signal intensity (lower panel, Figure 6).


Magnetic resonance-guided regional gene delivery strategy using a tumor stroma-permeable nanocarrier for pancreatic cancer.

Wang Q, Li J, An S, Chen Y, Jiang C, Wang X - Int J Nanomedicine (2015)

Confocal luminescence microscopy showing the in vivo distribution and amount of RFP expressed after transfection by naked plasmid or nanoparticles. Upper panel shows Gd-DTPA/pRFP (Gd-DTPA), middle panel shows Gd-DP/pRFP (Gd-DP), and lower panel shows Gd-DPT/pRFP (Gd-DPT). Red indicates RFP, blue indicates DAPI-stained cell nuclei, and yellow lines indicate crevices in tumor tissue. Original magnification 200×.Abbreviations: Gd, gadolinium; DAPI, 4,6-diamidino-2-phenylindole; pRFP, plasmid red fluorescence protein; DGL, dendrigraft poly-L-lysine; PEG, polyethylene glycol; DTPA, gadopentetate dimeglumine; DP, DTPA-DGL-PEG; DPT, DTPA-DGL-PEG-TAT.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4508066&req=5

f6-ijn-10-4479: Confocal luminescence microscopy showing the in vivo distribution and amount of RFP expressed after transfection by naked plasmid or nanoparticles. Upper panel shows Gd-DTPA/pRFP (Gd-DTPA), middle panel shows Gd-DP/pRFP (Gd-DP), and lower panel shows Gd-DPT/pRFP (Gd-DPT). Red indicates RFP, blue indicates DAPI-stained cell nuclei, and yellow lines indicate crevices in tumor tissue. Original magnification 200×.Abbreviations: Gd, gadolinium; DAPI, 4,6-diamidino-2-phenylindole; pRFP, plasmid red fluorescence protein; DGL, dendrigraft poly-L-lysine; PEG, polyethylene glycol; DTPA, gadopentetate dimeglumine; DP, DTPA-DGL-PEG; DPT, DTPA-DGL-PEG-TAT.
Mentions: A few cells with a weak luminescence signal in the tumors treated with the Gd-DTPA and pRFP complexes were detected using confocal luminescence microscopy, indicating that there was limited gene transfer when injecting naked plasmid (upper panel, Figure 6). The pRFP loaded by Gd-DP was better translated in a single cancer cell compared with Gd-DTPA/pRFP, demonstrating that dendrimers could protect the plasmid from being degraded in the lysosome24 (middle panel, Figure 6). Additionally, for both of the above groups, the transfected cells settled along crevices in the tumor tissue. However, expression of RFP in cells treated with Gd-DPT/pRFP was homogeneous in its distribution and had a strong signal intensity (lower panel, Figure 6).

Bottom Line: Third-generation dendrigraft poly-L-lysines was selected as the nanocarrier scaffold, which was modified by cell-penetrating peptides and gadolinium (Gd) chelates.Permeability of the nanoparticles modified by cell-penetrating peptides was superior to that of the unmodified counterpart, demonstrating the improved capability of nanoparticles for diffusion in tumor stroma on magnetic resonance imaging.This study demonstrated that an image-guided gene delivery system with a stroma-permeable gene vector could be a potential clinically translatable gene therapy strategy for PDAC.

View Article: PubMed Central - PubMed

Affiliation: Department of Interventional Radiology, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China ; Shanghai Institute of Medical Imaging, Fudan University, Shanghai, People's Republic of China.

ABSTRACT

Background: Gene therapy is a very promising technology for treatment of pancreatic ductal adenocarcinoma (PDAC). However, its application has been limited by the abundant stromal response in the tumor microenvironment. The aim of this study was to prepare a dendrimer-based gene-free loading vector with high permeability in the tumor stroma and explore an imaging-guided local gene delivery strategy for PDAC to promote the efficiency of targeted gene delivery.

Methods: The experimental protocol was approved by the animal ethics committee of Zhongshan Hospital, Fudan University. Third-generation dendrigraft poly-L-lysines was selected as the nanocarrier scaffold, which was modified by cell-penetrating peptides and gadolinium (Gd) chelates. DNA plasmids were loaded with these nanocarriers via electrostatic interaction. The cellular uptake and loaded gene expression were examined in MIA PaCa-2 cell lines in vitro. Permeability of the nanoparticles in the tumor stroma and transfected gene distribution in vivo were studied using a magnetic resonance imaging-guided delivery strategy in an orthotopic nude mouse model of PDAC.

Results: The nanocarriers were synthesized with a dendrigraft poly-L-lysine to polyethylene glycol to DTPA ratio of 1:3.4:8.3 and a mean diameter of 110.9±7.7 nm. The luciferases were strictly expressed in the tumor, and the luminescence intensity in mice treated by Gd-DPT/plasmid luciferase (1.04×10(4)±9.75×10(2) p/s/cm(2)/sr) was significantly (P<0.05) higher than in those treated with Gd-DTPA (9.56×10(2)±6.15×10 p/s/cm(2)/sr) and Gd-DP (5.75×10(3)± 7.45×10(2) p/s/cm(2)/sr). Permeability of the nanoparticles modified by cell-penetrating peptides was superior to that of the unmodified counterpart, demonstrating the improved capability of nanoparticles for diffusion in tumor stroma on magnetic resonance imaging.

Conclusion: This study demonstrated that an image-guided gene delivery system with a stroma-permeable gene vector could be a potential clinically translatable gene therapy strategy for PDAC.

No MeSH data available.


Related in: MedlinePlus