Rawan Hassan Al-Saeedi - Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Mohammad Khalaj-Kondori - Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Mohammad Ali Hosseinpour Feizi - Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran.
Jafar Hajavi - Department of Microbiology, Faculty of Medicine, Infectious Diseases Research Center, Gonabad University of Medical Science, Gonabad, Iran & Innovative Medical Research Center, Mashhad Branch, Islamic Azad University, Mashhad, Iran.

Background: Inflammation contributes to cancer pathobiology through different mechanisms. Higher levels of pro-inflammatory cytokines can lead to hyperinflammation and promote cancer development and metastasis. For cancer treatment, Doxorubicin (DOX) can be encapsulated into the poly-lactic-glycolic acid (PLGA) nanoparticles. This study aimed to investigate the impact of doxorubicin-loaded PLGA nanoparticles (DOX-PLGA NP) on the expression of pro-inflammatory genes TNF-α, IL-۶, iNOS, and IL-۱β in the MCF-۷ cells. Methods: The DOX-PLGA NP was prepared by loading doxorubicin into PLGA and characterized using dynamic light scattering (DLS) and atomic force microscopy (AFM). The cytotoxic effect of the nanoparticles was determined by the MTT assay, and their impacts on the expression of pro-inflammatory genes were assessed by qRT-PCR. Results: The encapsulation efficiency and loading capacity were ۶۰±۱.۵ and ۱.۱۳±۰.۲۱ percent, respectively. The zeta potential and mean DOX-PLGA nanoparticle size were -۱۸±۰.۵۵۰ mV and ۱۷۲±۵۵.۶ nm, respectively. The ۵۰% inhibitory concentration (IC۵۰) of the DOX-PLGA NP on MCF-۷ cell viability was ۲۴.۵۵ µg/mL after ۷۲ hours of treatment. The qRT-PCR results revealed that the ۲۰ µg/mL concentration of the DOX-PLGA NP significantly suppressed the expression of the pro-inflammatory genes TNF-α, IL-۶, iNOS, and IL-۱β compared to DOX alone (۲۰ µg/mL). Additionally, the suppression effect of DOX-PLGA NP on the expression of these pro-inflammatory genes was dose-dependent. Conclusion: These results show that DOX-PLGA NP efficiently suppressed the expression of pro-inflammatory genes. Furthermore, encapsulation of DOX into PLGA nanoparticles significantly improved the effectiveness of DOX in suppressing pro-inflammatory genes in MCF-۷ breast cancer cells.

Breast cancer, Cytokines, Doxorubicin, Polylactic Acid-Polyglycolic Acid Copolymer, Pro-inflammatory cytokine.