Modified Linear Peptides Effectively Silence STAT-3 in Breast Cancer and Ovarian Cancer Cell Lines

Authors

Dindyal Mandal, Chapman UniversityFollow
Sandeep Lohan, Chapman UniversityFollow
Muhammad Imran Sajid, Chapman UniversityFollow
Abdulelah Alhazza, Chapman UniversityFollow
Rakesh Kumar Tiwari, Chapman UniversityFollow
Keykavous Parang, Chapman UniversityFollow
Hamidreza Montazeri Aliabadi, Chapman UniversityFollow

Document Type

Article

Publication Date

2-16-2023

Abstract

RNA interference (RNAi) has drawn enormous attention as a powerful tool because of its capability to interfere with mRNA and protein production. However, designing a safe and efficient delivery system in RNAi therapeutics remains challenging. Herein, we have designed and synthesized several linear peptides containing tryptophan (W) and arginine (R) residues separated by the β-alanine (βA) spacer and attached to a lipophilic fatty acyl chain, cholesterol, or PEG. The peptide backbone sequences were: Ac-C-βA-βA-W4-βA-βA-R4-CO-NH2 and Ac-K-βA-βA-W4-βA-βA-R4-CO-NH2, with only a difference in N-terminal amino acid. The cysteine side chain in the first sequence was used for the conjugation with PEG2000 and PEG550. Alternatively, the side chain of lysine in the second sequence was used for conjugation with cholesterol or oleic acid. We hypothesized that amphiphilic peptides and optimum fatty acyl chain or PEG could function as an effective siRNA carrier by complementing each structural component’s self-assembly and membrane internalization properties. None of the designed peptides showed cytotoxicity up to 10 µM. Serum stability studies suggested that the newly designed peptides efficiently protected siRNA against early degradation by nucleases. Flow cytometry analysis indicated 50–90% cellular uptake of siRNA using the newly developed modified linear peptides (MLPs). Western blot results revealed more than 90% protein downregulation after targeting STAT3 in MDA-MB-231 and SKOV-3 cell lines. In summary, a new peptide class was developed to safely and efficiently deliver siRNA.

Comments

This article was originally published in Pharmaceutics, volume 15, in 2023. https://doi.org/10.3390/pharmaceutics15020666

Recommended Citation

Mandal, D.; Lohan, S.; Sajid, Parang, K.; Montazeri Aliabadi, H. Modified Linear Peptides Effectively Silence STAT-3 in Breast Cancer and Ovarian Cancer Cell Lines. Pharmaceutics 2023, 15, 666. https://doi.org/10.3390/pharmaceutics15020666

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This work is licensed under a Creative Commons Attribution 4.0 License.