Limits...
Redox-responsive targeted gelatin nanoparticles for delivery of combination wt-p53 expressing plasmid DNA and gemcitabine in the treatment of pancreatic cancer.

Xu J, Singh A, Amiji MM - BMC Cancer (2014)

Bottom Line: Efficacy studies demonstrate an improved in vivo targeting efficiency resulting in increased transfection efficiency and tumor growth suppression.Gene/drug combination treatment significantly improves the therapeutic performance of the delivery system compared to the gene or drug alone treated groups.Anti-tumor activity of the thiolated gelatin loaded wt-p53 plasmid or gemcitabine-based therapy was attributed to their ability to induce cell apoptosis, which was confirmed by a marked increase in mRNA level of proapoptotic transcription factors, as well as, protein apoptotic biomarker expression and significant decrease in the anti-apoptotic transcription factors.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA. m.amiji@neu.edu.

ABSTRACT

Background: Pancreatic adenocarcinoma is one of the most dreaded cancers with very low survival rate and poor prognosis to the existing frontline chemotherapeutic drugs. Gene therapy in combination with a cytotoxic agent could be a promising approach to circumvent the limitations of previously attempted therapeutic interventions.

Method: We have developed a redox-responsive thiolated gelatin based nanoparticle system that efficiently delivers its payload in the presence of glutathione-mediated reducing intra-cellular environment and could be successfully used for site-specific wt-p53 expressing plasmid DNA as well as gemcitabine delivery by targeting epidermal growth factor receptor (EGFR). Efficacy studies were performed in subcutaneous human adenocarcinoma bearing SCID beige mice along with molecular level p53 plasmid and apoptotic marker expression by PCR and western blot for all study groups.

Results: Efficacy studies demonstrate an improved in vivo targeting efficiency resulting in increased transfection efficiency and tumor growth suppression. In all the treatment groups, the targeted nanoparticles showed better anti-tumor activity than their non-targeted as well as non-encapsulated, naked therapeutic agent counterparts (50.1, 61.7 and 77.3% tumor regression by p53 plasmid alone, gemcitabine alone and in combination respectively). Molecular analysis revealed a higher mRNA expression of transfected p53 gene, its corresponding protein and that the tumor cell death in all treatment groups was due to the induction of apoptotic pathways.

Conclusions: Gene/drug combination treatment significantly improves the therapeutic performance of the delivery system compared to the gene or drug alone treated groups. Anti-tumor activity of the thiolated gelatin loaded wt-p53 plasmid or gemcitabine-based therapy was attributed to their ability to induce cell apoptosis, which was confirmed by a marked increase in mRNA level of proapoptotic transcription factors, as well as, protein apoptotic biomarker expression and significant decrease in the anti-apoptotic transcription factors.

Show MeSH

Related in: MedlinePlus

In vivo efficacy assessment of wt-p53/gemcitabine combination treatment. (a) Volume change as a function of time showing 57.6***, 63.3.7*** and 77.3%*** reduction in tumor growth on day 33 for SH-Gel, SH-Gel-PEG and SH-Gel-PEG-peptide nanoparticle treated tumor respectively. (b) Tumor weights measured at day 33. Results are presented as mean ± SD (n = 6; ***p < 0.001).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC3927583&req=5

Figure 5: In vivo efficacy assessment of wt-p53/gemcitabine combination treatment. (a) Volume change as a function of time showing 57.6***, 63.3.7*** and 77.3%*** reduction in tumor growth on day 33 for SH-Gel, SH-Gel-PEG and SH-Gel-PEG-peptide nanoparticle treated tumor respectively. (b) Tumor weights measured at day 33. Results are presented as mean ± SD (n = 6; ***p < 0.001).

Mentions: We studied the efficacy of wt-p53 and gemcitabine combination treatment in subcutaneous human pancreatic adenocarcinoma bearing female SCID beige mice. The tumor bearing animals (n = 6) first received 3 doses of wt-p53 plasmid (20 μg plasmid/dose) encapsulated in thiolated, non-targeted and EGFR-targeted thiolated gelatin nanoparticles at day 0, 2 and 4. Gemcitabine conjugated to gelatin was administered in 4 weekly doses (5 mg/kg) at day 5, 12, 19 and 24. Tumor volume measurement during the course of the study showed maximum tumor growth inhibition by targeted nanoparticle based combination treatment (77.3%, p < 0.001) while non-targeted and non-PEG modified systems showed 63.3 and 57.6% (p < 0.001) growth inhibition (Figure 5a) compared to control. Importantly, combination treatment by targeted system proved to be most effective in tumor growth inhibition compared to individual wt-p53 gene (Figure 1a) or gemcitabine (Figure 4a) treatment using same delivery system (50.1 and 61.7% respectively).


Redox-responsive targeted gelatin nanoparticles for delivery of combination wt-p53 expressing plasmid DNA and gemcitabine in the treatment of pancreatic cancer.

Xu J, Singh A, Amiji MM - BMC Cancer (2014)

In vivo efficacy assessment of wt-p53/gemcitabine combination treatment. (a) Volume change as a function of time showing 57.6***, 63.3.7*** and 77.3%*** reduction in tumor growth on day 33 for SH-Gel, SH-Gel-PEG and SH-Gel-PEG-peptide nanoparticle treated tumor respectively. (b) Tumor weights measured at day 33. Results are presented as mean ± SD (n = 6; ***p < 0.001).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3927583&req=5

Figure 5: In vivo efficacy assessment of wt-p53/gemcitabine combination treatment. (a) Volume change as a function of time showing 57.6***, 63.3.7*** and 77.3%*** reduction in tumor growth on day 33 for SH-Gel, SH-Gel-PEG and SH-Gel-PEG-peptide nanoparticle treated tumor respectively. (b) Tumor weights measured at day 33. Results are presented as mean ± SD (n = 6; ***p < 0.001).
Mentions: We studied the efficacy of wt-p53 and gemcitabine combination treatment in subcutaneous human pancreatic adenocarcinoma bearing female SCID beige mice. The tumor bearing animals (n = 6) first received 3 doses of wt-p53 plasmid (20 μg plasmid/dose) encapsulated in thiolated, non-targeted and EGFR-targeted thiolated gelatin nanoparticles at day 0, 2 and 4. Gemcitabine conjugated to gelatin was administered in 4 weekly doses (5 mg/kg) at day 5, 12, 19 and 24. Tumor volume measurement during the course of the study showed maximum tumor growth inhibition by targeted nanoparticle based combination treatment (77.3%, p < 0.001) while non-targeted and non-PEG modified systems showed 63.3 and 57.6% (p < 0.001) growth inhibition (Figure 5a) compared to control. Importantly, combination treatment by targeted system proved to be most effective in tumor growth inhibition compared to individual wt-p53 gene (Figure 1a) or gemcitabine (Figure 4a) treatment using same delivery system (50.1 and 61.7% respectively).

Bottom Line: Efficacy studies demonstrate an improved in vivo targeting efficiency resulting in increased transfection efficiency and tumor growth suppression.Gene/drug combination treatment significantly improves the therapeutic performance of the delivery system compared to the gene or drug alone treated groups.Anti-tumor activity of the thiolated gelatin loaded wt-p53 plasmid or gemcitabine-based therapy was attributed to their ability to induce cell apoptosis, which was confirmed by a marked increase in mRNA level of proapoptotic transcription factors, as well as, protein apoptotic biomarker expression and significant decrease in the anti-apoptotic transcription factors.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA. m.amiji@neu.edu.

ABSTRACT

Background: Pancreatic adenocarcinoma is one of the most dreaded cancers with very low survival rate and poor prognosis to the existing frontline chemotherapeutic drugs. Gene therapy in combination with a cytotoxic agent could be a promising approach to circumvent the limitations of previously attempted therapeutic interventions.

Method: We have developed a redox-responsive thiolated gelatin based nanoparticle system that efficiently delivers its payload in the presence of glutathione-mediated reducing intra-cellular environment and could be successfully used for site-specific wt-p53 expressing plasmid DNA as well as gemcitabine delivery by targeting epidermal growth factor receptor (EGFR). Efficacy studies were performed in subcutaneous human adenocarcinoma bearing SCID beige mice along with molecular level p53 plasmid and apoptotic marker expression by PCR and western blot for all study groups.

Results: Efficacy studies demonstrate an improved in vivo targeting efficiency resulting in increased transfection efficiency and tumor growth suppression. In all the treatment groups, the targeted nanoparticles showed better anti-tumor activity than their non-targeted as well as non-encapsulated, naked therapeutic agent counterparts (50.1, 61.7 and 77.3% tumor regression by p53 plasmid alone, gemcitabine alone and in combination respectively). Molecular analysis revealed a higher mRNA expression of transfected p53 gene, its corresponding protein and that the tumor cell death in all treatment groups was due to the induction of apoptotic pathways.

Conclusions: Gene/drug combination treatment significantly improves the therapeutic performance of the delivery system compared to the gene or drug alone treated groups. Anti-tumor activity of the thiolated gelatin loaded wt-p53 plasmid or gemcitabine-based therapy was attributed to their ability to induce cell apoptosis, which was confirmed by a marked increase in mRNA level of proapoptotic transcription factors, as well as, protein apoptotic biomarker expression and significant decrease in the anti-apoptotic transcription factors.

Show MeSH
Related in: MedlinePlus