Functional Downregulation of PD-L1 and PD-L2 by CpG and non-CpG Oligonucleotides in Melanoma Cells

The clinical application of immune checkpoint inhibitors represents a breakthrough progress in the treatment of metastasized melanoma and other tumor entities. In the present study, it was hypothesized that oligonucleotides (ODNs), known as modulators of the immune response, have an impact on the endogenous expression of checkpoint molecules, namely PD-L1 and PD-L2 (PD-L1/2). IFNγ-stimulated melanoma cells (A375, SK-Mel-28) were treated with different synthetically manufactured oligonucleotides which differed in sequence, length and backbone composition. It was found that a variety of different ODN sequences significantly suppressed PD-L1/2 expression. This effect was dependent on length and phosphorothioate (PTO) backbone. In particular, a sequence containing solely guanines (nCpG-6-PTO) was highly effective in downregulating PD-L1/2 at the protein, mRNA and promoter levels. Mechanistically, we gave evidence that ODNs with G-quartet-forming motifs suppress the interferon signaling axis (JAK/STAT/IRF1). Our findings identify a subset of ODNs as interesting pharmacological compounds that could expand the arsenal of targeted therapies to combat the immunological escape of tumor cells.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:14

Enthalten in:

Cancers - 14(2022), 19 vom: 27. Sept.

Sprache:

Englisch

Beteiligte Personen:

Kleemann, Johannes [VerfasserIn]
Steinhorst, Katja [VerfasserIn]
König, Veronika [VerfasserIn]
Zöller, Nadja [VerfasserIn]
Cinatl, Jindrich [VerfasserIn]
Özistanbullu, Deniz [VerfasserIn]
Kaufmann, Roland [VerfasserIn]
Meissner, Markus [VerfasserIn]
Kippenberger, Stefan [VerfasserIn]

Links:

Volltext

Themen:

Checkpoint
IFNγ
IRF1
JAK
Journal Article
Melanoma
Oligonucleotide
PD-L1
PD-L2
Quadruplex
STAT

Anmerkungen:

Date Revised 17.10.2022

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.3390/cancers14194698

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM347456855