In VitroDose Studies on Chitosan Nanoplexes for microRNA Delivery in Breast Cancer Cells

Abstract

Changes in microRNA (miRNA) expression levels that play important roles in regulation lead to many pathological events such as cancer. The miR-200 family is an important target in cancer therapy. The aim of this study is to equilibrate endogenous levels between cancer and noncancerous cells to prevent serious side effects of miR-200c- and miR-141-like metastatic colonization. For the first time, the characterization of miR-200c and miR-141 cluster containing chitosan nanoplexes was shown, and the optimization of miRNA expression levels by conducting dose studies in breast cancer cell lines was made. The mean diameter of chitosan/miR-141 and chitosan/miR-200c nanoplexes ranged from 296 to 355 nm and from 294 to 380 nm depending on the N/P ratio, respectively. The surface charge of nanoplexes was positive with zeta potential of +12 to +26 mV. While naked miRNA was degraded after 0 min in a 10% serum-containing medium, chitosan/miRNA nanoplexes were protected for 72 h. During the in vitro cellular uptake study, nanoplexes were observed to be accumulating in the cytoplasm or nucleus. After using different doses for miR-200c, the determined doses are 750, 100, and 750 ng in the MCF-7, MDA-MB-231, and MDA-MB-435 cell lines, respectively. Doses were determined as 100 ng for MDA-MB-231 and 150 ng for MDA-MB-435 to reach endogenous miR-141 levels of MCF-10A. Our results suggest that chitosan nanoplexes for miR-200c and miR-141 are an efficient delivery system in terms of formulation and transfection. As a conclusion, dose studies are important to provide effective treatment with miRNAs.

Modulating Macrophage Phenotype by Sustained MicroRNA Delivery Improves Host‐Implant Integration

“…We showed that by encapsulating miRs within PCLEEP fibers, a sustained release of miRs could be achieved for at least 30 days (Figure E). Besides that, as miR dosage is an important determinant in achieving favorable biological responses, the maximum amount of miR that could be loaded into each scaffold was utilized. Apart from the chemical cues from miRs, topographical signals, in the form of fiber diameter and alignment, also impact cellular behavior.…”

Treating cancer with microRNA replacement therapy: A literature review

“…Moreover, the use of chitosan as a cationic polymer with a profound nucleic acid binding tendency has been widely examined for delivery of miRNAs (Mao, Sun, & Kissel, ). Kaban, Salva, and Akbuga (, ) and optimized co‐delivery of miR‐200c with chitosan nanoparticles into breast cancer cells in vitro. Efficient delivery of miR‐34a into bone metastasis model of prostate cancer using chitosan nanocarriers in vivo resulted in decreased tumor size (Gaur et al, ).…”

MiRNA-Based Therapeutics in Oncology, Realities, and Challenges

“…Ibrahim et al [42] have demonstrated that by using low molecular weight, PEIs as system delivery for miR-145 and miR-33a would decrease the toxicity and increase the antitumor effect, in a model of colon carcinoma. Recent studies [43,44] have proved that codelivery of miR-200c with chitosan, a cationic polymer with a high specificity for nucleic acid binding, decreased the angiogenesis, invasion, EMT, and metastasis and increased the apoptosis, highlighting the role of miRNA concentration in treatment effectiveness. Hao et al [45] used miRNA (MiR-15a, miR16-1)/ATE-APT complex formed by atelocollagen (ATE), a type I collagen positively charged polymer, in combination with a RNA aptamer (APT) used as a ligand to target PCa cells that express prostate-specific membrane antigen (PSMA).…”