Downregulation of CD73 in 4T1 breast cancer cells through siRNA-loaded chitosan-lactate nanoparticles

Abstract

The immunosuppressive factors in tumor microenvironment enhance tumor growth and suppress anti-tumor immune responses. Adenosine is an important immunosuppressive factor which can be secreted by both tumor and immune cells trough action of two cell surface ecto-nucleotidase molecules CD39 and CD73. Blocking the adenosine generating molecules has emerged as an effective immunotherapeutic approach for treatment of cancer. In this study, CD73-siRNA encapsulated into chitosan-lactate (ChLa) nanoparticles (NPs) was employed to suppress the expression of CD73 molecule on 4T1 breast tumor cells, in vitro. ChLa NPs were generated through ionic gelation of ChLa by tripolyphosphate (TPP). Small interfering RNA (SiRNA)-loaded NPs had about 100 nm size with a polydispersive index below 0.3 and a zeta potential about 13. Our results showed that ChLa NPs with Ch 50 kDa exhibit the best physicochemical features with the high siRNA encapsulation capacity. Synthesized NPs were able to fully bind with siRNA, protect them against serum and heparin degradation, and promote the transfection process. While the NPs exhibited low toxicity during 72 h cell culture, the transfection of Ch-plasmid expressing green fluorescent protein (pEGFP) NPs was efficient in 4T1 cells with a transfection rate of 53.6 % as detected by flow cytometry. In addition, CD73-siRNA-loaded ChLa NPs could efficiently suppress the expression of CD73 as assayed by real-time polymerase chain reaction and flow cytometry. As a conclusion, CD73-siRNA-loaded ChLa NPs may be considered as a promising therapeutic tool for cancer therapy; however, further in vivo investigations are necessary.

Anti‐angiogenic effects of CD73‐specific siRNA‐loaded nanoparticles in breast cancer‐bearing mice

“…Generated ChLa NPs showed the high siRNA encapsulation efficacy and could highly protect siRNA molecules from the degradation. A transfection efficiency was more than 50% which led to potent downregulation of CD73 expression in 4T1 cells, as details published previously (Jadidi‐Niaragh et al, ). Using FITC conjugated NPs, we have recently been shown that NPs were significantly accumulated in the tumor site in the tumor‐bearing mice (Jadidi‐Niaragh et al, ).…”

Engineered nanoparticles induce cell apoptosis: potential for cancer therapy

“…In such a process normal cells may be spared [97]. ENPs are also explored as small interfering RNA (siRNA) carriers in the treatment of breast cancer [98], ovarian cancer [99], hepatocellular carcinoma [100], and B-cell malignancies [101] etc., as methods in gene silencing therapy. The above examples show that ENP-dependent drug delivery systems prove to be a promising therapeutic system for the treatment of cancer.…”

Co-delivery of IL17RB siRNA and doxorubicin by chitosan-based nanoparticles for enhanced anticancer efficacy in breast cancer cells

“…In addition, considering the inherent characteristics of Chitosan, in order to inhibit drug resistance induced by DOX as well as the reduction in dose and cytotoxicity and conversely, to increase the survival time of drug in body, the nanoparticles of Chitosan were used for the transportation of the drug. So this system can be used as a novel and effective DDS for breast cancer treatment [34]. Also the present system can be used in vivo.…”

“…The Preparation of DOX-siRNA-CMD-ChNP, DOX-CMD-ChNP, and siRNA-CMD-ChNP was performed according to the methods reported by Jadidi-Niaragh, et al with some modifications [34]. In order to prepare ChNPs with different concentrations of DOX (Sigma, USA) and IL17RB siRNA (Santa Cruz Biotech, USA), 100 ml CMD, (Sigma, Aldrich, USA) at the concentration of 1 mg/ml in deionized water, was added to 10, 5, 2.5 and 1.25 mg/ml of DOX, respectively.…”