biostudies-literatureKunz MProjekt DEALWilhelm Sander-StiftungWilhelm Sander-Stiftung (DE)173https://www.ebi.ac.uk/biostudies/studies/S-EPMC7685669biostudies-literatureUnknown18(1)<h4>Background</h4>MiRNAs act as negative regulators of gene expression through target mRNA degradation or inhibition of its translation. In cancer, several miRNAs are upregulated and play crucial roles in tumorigenesis, making the inhibition of these oncomiRs an interesting therapeutic approach. This can be achieved by directly complementary single-stranded anti-miRNA oligonucleotides (antimiRs). A major bottleneck in antimiR therapy, however, is their efficient delivery. The nanoparticle formation with polyethylenimine (PEI) may be particularly promising, based on the PEI's ability to electrostatically interact with oligonucleotides. This leads to their protection and supports delivery. In the present study, we explore for the first time PEI for antimiR formulation and delivery. We use tJournal of nanobiotechnologyNanoparticle-complexed antimiRs for inhibiting tumor growth and metastasis in prostate carcinoma and melanoma.PMC76856692015.171.12015.191.1Kunz MBrandl MAigner AWeigelt KKalwa HTaubert HGuzman JBhattacharya AEwe ANobereit-Siegel LWeirauch UWach SReinert AHering DfalseNanoparticle-complexed antimiRs for inhibiting tumor growth and metastasis in prostate carcinoma and melanoma.<h4>Background</h4>MiRNAs act as negative regulators of gene expression through target mRNA degradation or inhibition of its translation. In cancer, several miRNAs are upregulated and play crucial roles in tumorigenesis, making the inhibition of these oncomiRs an interesting therapeutic approach. This can be achieved by directly complementary single-stranded anti-miRNA oligonucleotides (antimiRs). A major bottleneck in antimiR therapy, however, is their efficient delivery. The nanoparticle formation with polyethylenimine (PEI) may be particularly promising, based on the PEI's ability to electrostatically interact with oligonucleotides. This leads to their protection and supports delivery. In the present study, we explore for the first time PEI for antimiR formulation and delivery. We use t2020-01-01T00:00:00Z2020 Nov2026-04-30T08:13:33.745Z2026-04-07T15:56:44.889ZS-EPMC76856693322871110.1186/s12951-020-00728-w