title: Investigating the Sensitivity of Non-Small Cell Lung Cancer to Cisplatin using MicroRNA-184 loaded Chitosan Nanocarriers
Creators: name: Scagnetti, G
Publisher: name: Liverpool John Moores University
Year: 2025

description: Lung cancer cancer is the number one cause of death worldwide. The difficulty of detecting the malignancy at early stages of its progression is the primary reason for the high mortality related to lung cancer. When surgery is not a feasible option, cisplatin and platinum-based compounds are the first-line therapeutic agents employed to treat patients. However, cisplatin treatment often results in unsuccessful therapies owing to the development of drug resistance. Progress has been made in last decade to improve the chemotherapeutic approach to lung cancer, such as drugs targeting genetic modifications and immunotherapy. However, for majority of the patients cisplatin-based therapy is still the primary choice. Oligonucleotide therapeutics have increased in the past 20 years as novel compounds to treat several pathologies including cancer. They are based on the mimicry or inhibition of noncoding RNAs, which are known to be involved in the regulation of gene expression. To date, more than 15 drugs have been approved by the FDA for human use, which showcase the great promise held by this compound class. MicroRNAs are short non-coding oligonucleotide which modulate protein expression. Since their discovery, they have been involved in several steps of carcinogenesis, including the development of drug resistance. One possible approach to tackle lung cancer was to sensitise cells to cisplatin via modulating the expression of miRNA involved in cisplatin resistance. Among the miRNA involved in the development of drug resistance, this work was focused on a miRNA named miR-184, which was demonstrated to be downregulated in non-small cell lung cancer (NSCLC) cells. Our results showed that the transfection of Calu-3 cells with miR-184 mimic sensitised the cells to cisplatin, diminishing its IC50 from 14.35 ± 1.28 μM to 9.42 ± 1.47 μM. Furthermore, our results suggested that cisplatin treatment together with miR-184 mimic transfection increased Calu-3 (epithelial adenocarcinoma) apoptotic and necrotic cell populations, in comparison to cisplatin only treatment. Thus, showing promise in miR-184 as a therapeutic target for lung cancer. One of the major difficulties related to oligonucleotide therapeutics is their challenging delivery. These include events that prevent oligonucleotide to exert their action, such as nuclease degradation, poor internalisation at the cellular level and lysosomal degradation once uptaken from the cells. One promising approach to enhance oligonucleotide therapeutics is represented by their complexation within nanoparticles (NPs). This study developed a NPs formulation using chitosan derivatives employing the Taguchi Design of Experiment to find the optimum formulation (L18 orthogonal array). The formulations were prepared within a microfluidic device, which allows quick preparation and easier scalability of the formulation compared to conventional methods. The manufactured CHT NPs were of a nano-meter size range and the optimum formulation had size of 105.9 ± 11.00 nm for CS HCl, 142.73 ± 6.60 nm for CS GLU, 199.20 ± 8.50 nm for CS GLY and 142.15 ± 5.75 nm for CS ASP. In addition, NPs were able to complex with the miR-184 mimic (EE% &gt; 91.83 ± 0.89). Confocal microscopy revealed that the NPs were successfully internalised by Calu-3 cells, thus confirming that the formulation enhanced the oligonucleotide uptake. Finally, the current study investigated the expression of four known miR-184 targets (BCL-2, c.myc, TNFAIP-2, AKT-2) to explore the mechanism to enhance cisplatin cytotoxicity. Our findings revealed that miR-184 might enhance cisplatin cytotoxicity via targeting BCL-2 (and therefore inducing apoptosis), and/or c-myc and TNFAIP-2 (and therefore decreasing cell proliferation).