Polyamines regulate adaptive antitumor immunity by functional specialization of regulatory T cells

In cancer, metabolic changes and uncontrolled tumor growth alter nutrient availability, impacting antitumor immune responses. Regulatory T (Treg) cells are a subset of T cells with immunosuppressive properties that has been found to additionally possess the ability to control tissue homeostasis and repair. However, it is not known how these functions are molecularly controlled and if they are influenced by tumor metabolism. Here, we report that excessive release of polyamines in the tumor microenvironment directs the functional polarization of Treg cells towards immunosuppression in a protein kinase CK2 (CK2)-dependent manner. Polyamine deprivation as well as genetic or pharmacological inhibition of CK2 activity in Treg cells induced tissue reparative properties in Treg cells that orchestrated efficient antitumor type 2 immune responses, and coordinated tissue repair mechanisms to support tumor eradication. These findings suggest the potential for targeted modulation of Treg cell functions, offering new avenues for cancer therapy. This dataset is intended to investigate the effect of DFMO on gene expression depending on the presence of CK2β, the beta subunit of protein kinase CK2. Spleens from wild-type mice (WT; Csnk2bfl/fl) (8–12 weeks old) and Foxp3-Cre × CK2b-fl/fl (KO; Csnk2bTreg-/-) mice were mechanically disrupted and filtered through a 40 µm cell strainer to remove debris. Red blood cells were lysed using Gey’s lysis buffer, followed by a second filtration through a 40 µm cell strainer. CD25+ CD4+ Regulatory T cells (Tregs) were isolated using the CD4+ CD25+ Regulatory T Cell Isolation Kit, mouse (Miltenyi Biotec; 130-091-041), according to the manufacturer’s instructions, using magnetic-activated cell sorting (MACS). A total of 2x10e5 isolated Tregs were stimulated in culture medium (Iscove’s Modified Dulbecco’s Medium (IMDM) supplemented with 10% (v/v) fetal calf serum (FCS), 0.1% (v/v) penicillin-streptomycin, 2 mM L-glutamine, 1 mM sodium pyruvate, and 50 µM β-mercaptoethanol). Cells were cultured in the presence of 250 ng/ml recombinant murine IL-2 (mrIL-2), anti-CD3/CD28 T-Cell Expander Beads (Gibco; 11452D) at a 2:1 bead-to-cell ratio, and 1 mM DFMO (difluoromethylornithine; MedChemExpress HY-B0744B). Cultures were maintained for 72 hours at 37 °C with 5% CO₂ in flat-bottom 96-well plates.