Abstract 2899: Antitumor activity of CIGB-300, a peptide CK2 inhibitor, in breast cancer models

Abstract

Abstract CK2 is a serine-threonine kinase that has been involved in growth, proliferation and cell apoptosis. CK2 has a constitutive expression and it has more than 300 substrates. In recent years, CK2 became an interesting target for anticancer therapies. Inhibition of CK2 showed antitumor activity in different types of cancer. Because breast cancer is one of the main tumor types in which CK2 is overexpressed, we focus on the effect of CK2 inhibition as a modulator of key features of breast cancer cell biology. The aim of the present study was to evaluate the role of inhibition of CK2 by CIGB-300 in murine and human mammary carcinoma cell lines. For this purpose, we evaluated the action of CIGB-300 on viability, apoptosis, cell cycle, clonogenic capacity and migration using three different breast tumor cell lines, MCF7 (positive for estrogen, progesterone and HER2-neu receptors), MDA MB 231 (representative of triple negative tumors) and F3II, a murine mammary carcinoma. As compared the potential of CK2 inhibition in these models we included another chemical inhibitor of the enzyme, CX-4945. Our results showed that CIGB-300 reduced the viability of MDA MB 231 (IC50=120 μM) and MCF-7 (IC50=140 μM) (p<0.05, ANOVA). We observed that in both human and murine cell lines CIGB-300 exerts a pro-apoptotic action (TUNEL assay, p<0.05, χ2) and arrest cell cycle. We also found that the inhibition of CK2 by CIGB-300 decreased the clonogenic capacity and migration of F3II, MCF-7 and MDA-MB-231 (p<0.05, ANOVA). In vivo studies using the syngeneic F3II breast cancer model in BalB/c mice showed a decrease in the number of lung metastases in mice treated systemically with CIGB-300 after primary tumor surgery (Mann Whitney test, p<0.05). However, CK2 inhibition did not affect the growth of local recurrences. Also, intravenous administration of CIGB-300 decreased lung metastasis development of F3II cells. These results demonstrate an antimetastatic effect of CIGB-300 in a systemic inoculation model after surgical removal of primary tumors. In this work we demostrated the antitumor effect of CIGB-300 in breast cancer models such as those reported in myeloid leukemia, lung and cervix and head cancer. Citation Format: Maria F. Gottardo, Carla S. Capibianco, Johanna E. Sidabra, Yasser Perera, Silvio Perea, Daniel F. Alonso, Hernan G. Farina. Antitumor activity of CIGB-300, a peptide CK2 inhibitor, in breast cancer models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2899.