**Conflict of interest**

The Author declares no conflicts of interest.

*Overcoming P-Glycoprotein-Mediated Doxorubicin Resistance DOI: http://dx.doi.org/10.5772/intechopen.95553*

*Advances in Precision Medicine Oncology*

pression in mice model [131].

**5. Conclusion**

**Acknowledgements**

in publishing this work.

**Conflict of interest**

in couple with utilization of P-gp modulators can overcome MDR and enhance therapeutic efficacy of doxorubicin. Furthermore, with cancer-targeting ability, this target specific delivery would limit the adverse effect to normal tissues. With the encapsulation technology, nanoparticles (NPs) loaded with doxorubicin and P-gp modulators or other molecules (e.g., siRNAs) has been reported their effectiveness in target delivery into the cells. For examples, aerosol OT (AOT)-alginate NPs enhanced cellular delivery of doxorubicin in MCF-7 cells [129]. Lipid-modified

dextran-based NPs loaded with doxorubicin and MDR1 siRNA significantly increased intracellular doxorubicin and reduced P-gp expression levels in osteosarcoma cell line, as compared to doxorubicin alone [130]. Doxorubicin-curcumin composite NPs (e.g., NanoDoxCurc, pegylated-DOX-CUR NPs) could enhance effects of doxorubicin both in vitro and in vivo models of DOX-resistant cancers (e.g., multiple myeloma, acute leukemia, prostate and ovarian cancers). In addition, doxorubicin-curcumin NPs did not cause cardiac toxicity and bone marrow sup-

Doxorubicin is an effective anti-cancer drug that has high MDR incidence. High expression of an efflux transporter P-gp is one established mechanism responsible for the loss of drug effectiveness and MDR development. This can be due to the P-gp function in preventing intracellular accumulation of doxorubicin up to its effective level. Several approaches have been introduced in order to increase the efficacy of doxorubicin-based chemotherapy and overcome MDR. The combination of doxorubicin and non-cytotoxic P-gp modulators, particularly when given to the specific target cancer can be a promising approach to increase cancer sensitivity to doxorubicin through suppression of P-gp function. With the novel encapsulation technologies, it is very possible to develop the drug delivery platforms with specific targeted cancer cells as well as improvement of doxorubicin delivery into the cells. By these means, enhancement of doxorubicin-mediated cytotoxicity can be achieved with minimal dosing of the anti-cancer drugs. After clinically approval, it will provide a

The author gratefully thanks IntechOpen Limited for the sponsorship program

great benefit to patients receiving doxorubicin-based chemotherapy.

The Author declares no conflicts of interest.

**200**
