IMIQUIMOD TREATMENT OF TRANSFORMED CELLS: NF-KB AND TLR-7/8 SIGNALLING INDEPENDENT DEATH

RABELLINI SOFÍA; WAINSTOK ROSA; CAMBINDO BOTTO ADRIÁN; ADRIANA COCHÓN; RODRIGO ROCCO; MUÑOZ MANUEL; SILVINA GAZZANIGA

Mar del Plata, Argentina

Congreso; Reunión anual de Sociedades Biocientíficas; 2019

The immunotherapeutic agent imiquimod (IQ), an agonist of the Toll-like receptors (TLR)7/8, has been reported to be effective in the treatment of several skin pathologies including melanoma and infantile haemangioma. In immune cells, the classic pathway for IQ signalling comprises TLR7 and NF-KB activation. Previously, we have demonstrated that IQ causes cell death, oxidative stress and loss of migratory ability in haemangioma and melanoma cells in vitro. In order to gain insight on IQ signalling mechanism in transformed cells, we studied TLR expression and the involvement of NF-kB in IQ-induced cell death.Murine melanoma B16F-1 and haemangioma H5V cells were treated with IQ (0, 5, 10 and 50 g/mL) in the presence or absence of an NF-KB inhibitor (BAY 11-7082) during 24 hours. Cell viability was analysed by crystal violet staining and nuclear morphological changes were evaluated by a nuclear morphometric analysis (NMA) with ImageJ on Höescht 33258-stained nuclei. TLR-7/8 expression was assayed by RT-qPCR. Both H5V and B16F-1 cells suffered loss of viability (circa 50%) at IQ 10 µg/mL but inhibition of NF-KB did not modify cell death levels. Likewise, NMA showed an increased number of small and regular nuclei (50-60%, p