Re-examination of Peptide-Sequence-Dependent Gene Expression of Cysteine-Installed Pegylated Oligolysine/DNA Complexes

Yuichi Yamasaki; Daiki Kumekawa; Satoshi Yamauchi; Hodaka Omuro

doi:10.1021/acsomega.2c00122

Re-examination of Peptide-Sequence-Dependent Gene Expression of Cysteine-Installed Pegylated Oligolysine/DNA Complexes

ACS Omega. 2022 Apr 27;7(18):15478-15487. doi: 10.1021/acsomega.2c00122. eCollection 2022 May 10.

Authors

Yuichi Yamasaki¹, Daiki Kumekawa¹, Satoshi Yamauchi¹, Hodaka Omuro¹

Affiliation

¹ Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan.

Abstract

We previously synthesized cysteine-installed C-terminally PEGylated oligolysines with 20 amino acid residues to form cross-linked polymeric micelles (PMs) with luciferase-coding plasmid DNA as a candidate for artificial gene vectors. Luciferase gene expression in HeLa cells mediated by PEG-CK₁₈C, PEG-CK₉CK₉, and PEG-K₉CK₉C was reported to be 35-, 5.4-, and 1.3-fold higher than that mediated by cysteine-uninstalled PEGylated oligolysine PEG-K₂₀, respectively. However, after the publication, the survival rate of HeLa cells used in the previous study was found to be lower than usual when subcutaneously implanted into mice to create a xenograft model. In this study, to re-examine the peptide sequence-dependent gene expression, gene expression efficacy mediated by PEG-peptide PMs was compared with the PM cellular uptake results using newly obtained HeLa cell lines and the additional cell lines Huh-7, PANC-1, and BxPC3. As a result, PEG-K₉CK₉C PMs mediated the maximum gene expression in all cell lines, and the corresponding cellular uptake was also obtained. Therefore, we concluded that our previous results were erroneously obtained due to normality-depleted HeLa cells. A comparison of physicochemical characterizations, gene expression efficacy, and cellular uptake of PEG-peptide PMs is discussed in detail.