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Inhibition of ABCB1 (MDR1) expression by an siRNA nanoparticulate delivery system to overcome drug resistance in osteosarcoma.

Susa M, Iyer AK, Ryu K, Choy E, Hornicek FJ, Mankin H, Milane L, Amiji MM, Duan Z - PLoS ONE (2010)

Bottom Line: However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy.In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery.The results also demonstrated that this approach may be capable of reversing drug resistance by increasing the amount of drug accumulation in MDR cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA.

ABSTRACT

Background: The use of neo-adjuvant chemotherapy in treating osteosarcoma has improved patients' average 5 year survival rate from 20% to 70% in the past 30 years. However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy.

Methodology/principal findings: In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery. Novel biocompatible, lipid-modified dextran-based polymeric nanoparticles were used as the platform for MDR1 siRNA delivery; and the efficacy of combination therapy with this system was evaluated. In this study, multi-drug resistant osteosarcoma cell lines (KHOS(R2) and U-2OS(R2)) were treated with the MDR1 siRNA nanocarriers and MDR1 protein (P-gp) expression, drug retention, and immunofluoresence were analyzed. Combination therapy of the MDR1 siRNA loaded nanocarriers with increasing concentrations of doxorubicin was also analyzed. We observed that MDR1 siRNA loaded dextran nanoparticles efficiently suppresses P-gp expression in the drug resistant osteosarcoma cell lines. The results also demonstrated that this approach may be capable of reversing drug resistance by increasing the amount of drug accumulation in MDR cell lines.

Conclusions/significance: Lipid-modified dextran-based polymeric nanoparticles are a promising platform for siRNA delivery. Nanocarriers loaded with MDR1 siRNA are a potential treatment strategy for reversing MDR in osteosarcoma.

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Related in: MedlinePlus

The effect of doxorubicin alone or nanoparticle loaded with MDR1 siRNA on KHOSR2 and U-2OSR2 was analyzed.Varying concentrations of doxorubicin was added and cells were cultured for 5 days. Treatment with nanoparticles loaded with MDR1 siRNA showed increased anti-proliferative activity in both drug resistant osteosarcoma cell lines, KHOSR2 (A) and U-2OSR2 (B), in a dose dependent manner. Growth inhibition was assessed by MTT as described under Materials and Methods. The experiment was repeated four times in triplicate.
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pone-0010764-g007: The effect of doxorubicin alone or nanoparticle loaded with MDR1 siRNA on KHOSR2 and U-2OSR2 was analyzed.Varying concentrations of doxorubicin was added and cells were cultured for 5 days. Treatment with nanoparticles loaded with MDR1 siRNA showed increased anti-proliferative activity in both drug resistant osteosarcoma cell lines, KHOSR2 (A) and U-2OSR2 (B), in a dose dependent manner. Growth inhibition was assessed by MTT as described under Materials and Methods. The experiment was repeated four times in triplicate.

Mentions: The dextran nanoparticles are not cytotoxic by themselves at the dose used in this study (data not shown). After treatment with MDR1 siRNA loaded nanoparticles, we found that doxorubicin showed an increased amount of anti-proliferative activity in drug resistant osteosarcoma cell lines in a dose dependent manner (Fig. 7A, B). With the delivery of nanoparticles loaded with 100 nM MDR1 siRNA, growth inhibition with doxorubicin was substantially more marked than with the administration of 100 fold higher amounts of free drugs. For example, in the KHOSR2 cell line the IC50 of doxorubicin alone was 10 µM which was reduced to 0.1 µM when the cells were co-treated with MDR1 siRNA loaded nanoparticles. Likewise, the drug resistant cell line U-2OSR2 displayed a similar trend; the IC50 for doxorubicin alone was 6 µM which was reduced to 0.06 µM when co-treated with the MDR1 siRNA loaded nanoparticles.


Inhibition of ABCB1 (MDR1) expression by an siRNA nanoparticulate delivery system to overcome drug resistance in osteosarcoma.

Susa M, Iyer AK, Ryu K, Choy E, Hornicek FJ, Mankin H, Milane L, Amiji MM, Duan Z - PLoS ONE (2010)

The effect of doxorubicin alone or nanoparticle loaded with MDR1 siRNA on KHOSR2 and U-2OSR2 was analyzed.Varying concentrations of doxorubicin was added and cells were cultured for 5 days. Treatment with nanoparticles loaded with MDR1 siRNA showed increased anti-proliferative activity in both drug resistant osteosarcoma cell lines, KHOSR2 (A) and U-2OSR2 (B), in a dose dependent manner. Growth inhibition was assessed by MTT as described under Materials and Methods. The experiment was repeated four times in triplicate.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2875382&req=5

pone-0010764-g007: The effect of doxorubicin alone or nanoparticle loaded with MDR1 siRNA on KHOSR2 and U-2OSR2 was analyzed.Varying concentrations of doxorubicin was added and cells were cultured for 5 days. Treatment with nanoparticles loaded with MDR1 siRNA showed increased anti-proliferative activity in both drug resistant osteosarcoma cell lines, KHOSR2 (A) and U-2OSR2 (B), in a dose dependent manner. Growth inhibition was assessed by MTT as described under Materials and Methods. The experiment was repeated four times in triplicate.
Mentions: The dextran nanoparticles are not cytotoxic by themselves at the dose used in this study (data not shown). After treatment with MDR1 siRNA loaded nanoparticles, we found that doxorubicin showed an increased amount of anti-proliferative activity in drug resistant osteosarcoma cell lines in a dose dependent manner (Fig. 7A, B). With the delivery of nanoparticles loaded with 100 nM MDR1 siRNA, growth inhibition with doxorubicin was substantially more marked than with the administration of 100 fold higher amounts of free drugs. For example, in the KHOSR2 cell line the IC50 of doxorubicin alone was 10 µM which was reduced to 0.1 µM when the cells were co-treated with MDR1 siRNA loaded nanoparticles. Likewise, the drug resistant cell line U-2OSR2 displayed a similar trend; the IC50 for doxorubicin alone was 6 µM which was reduced to 0.06 µM when co-treated with the MDR1 siRNA loaded nanoparticles.

Bottom Line: However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy.In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery.The results also demonstrated that this approach may be capable of reversing drug resistance by increasing the amount of drug accumulation in MDR cell lines.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedic Surgery, Massachusetts General Hospital, Boston, Massachusetts, USA.

ABSTRACT

Background: The use of neo-adjuvant chemotherapy in treating osteosarcoma has improved patients' average 5 year survival rate from 20% to 70% in the past 30 years. However, for patients who progress after chemotherapy, its effectiveness diminishes due to the emergence of multi-drug resistance (MDR) after prolonged therapy.

Methodology/principal findings: In order to overcome both the dose-limiting side effects of conventional chemotherapeutic agents and the therapeutic failure resulting from MDR, we designed and evaluated a novel drug delivery system for MDR1 siRNA delivery. Novel biocompatible, lipid-modified dextran-based polymeric nanoparticles were used as the platform for MDR1 siRNA delivery; and the efficacy of combination therapy with this system was evaluated. In this study, multi-drug resistant osteosarcoma cell lines (KHOS(R2) and U-2OS(R2)) were treated with the MDR1 siRNA nanocarriers and MDR1 protein (P-gp) expression, drug retention, and immunofluoresence were analyzed. Combination therapy of the MDR1 siRNA loaded nanocarriers with increasing concentrations of doxorubicin was also analyzed. We observed that MDR1 siRNA loaded dextran nanoparticles efficiently suppresses P-gp expression in the drug resistant osteosarcoma cell lines. The results also demonstrated that this approach may be capable of reversing drug resistance by increasing the amount of drug accumulation in MDR cell lines.

Conclusions/significance: Lipid-modified dextran-based polymeric nanoparticles are a promising platform for siRNA delivery. Nanocarriers loaded with MDR1 siRNA are a potential treatment strategy for reversing MDR in osteosarcoma.

Show MeSH
Related in: MedlinePlus