Abstract 2881: Antiproliferative effect of copper complex of clotam in neuroblastoma cell lines

Abstract

Neuroblastoma (NB) is the most common extracranial solid tumor in infants and young children. NB often metastasizes to lymph nodes and bone marrow. When compared to low or intermediate risk tumors, high risk neuroblastoma (HRNB) is more aggressive with low (40-50%) 5 year survival rates. Furthermore, current intensive treatment methods induce higher toxicity and side effects. In search of identifying less-toxic agents to induce anti-cancer activity in NB cells, our group reported the anti-cancer activity of a non-steroidal anti-inflammatory drug, Clotam (TA) using HRNB cell lines potentially inhibiting the transcription factor, Specificity protein 1 (Sp1) and an inhibitor of apoptosis protein, survivin. Recently, our laboratories tested a copper complex of TA (Cu-TA) using 12 cell lines and found that Cu-TA’s IC50 values were 30-80% lower when compared to TA. In this study, we investigated the cytotoxicity of SH-SY 5Y, LA1-55n and SMS-KCNR cells in the presence of vehicle (Dimethyl sulfoxide) or TA or Cu-TA using CellTiter-Glo kit and determined the IC50 values using SigmaPlot software. The effect of TA or Cu-TA on apoptosis and cell cycle phase distribution was evaluated by flow cytometry using Annexin-V and Propidium Iodide kits respectively. The characterization and stability of the Cu-TA was also determined. SH SY5Y and SMS-KCNR cells were treated with IC50 values of TA or Cu-TA and the expression of Sp1 and survivin was measured by qPCR and Western blot analysis. The results showed that while both TA and Cu-TA inhibited NB cell growth, Cu-TA’s IC50 values were 60-70% less than TA. The inhibition of NB cells with Cu-TA was accompanied by induced apoptotic cell population and cell cycle arrest at G2M phase. Western blot and qPCR results confirmed that Cu-TA inhibited the expression of both Sp1 and survivin with predominant effect on SMS-KCNR cells. These results demonstrate that Cu-TA is more effective than TA for inhibiting Sp1 and survivin in NB cells, which was consistent with the anti-proliferative activity against NB cells. Since TA and Cu-TA are less toxic than standard chemotherapeutic agents, employing these agents for the treatment of pediatric malignancies could be useful. Eventually, combination of Cu-TA and chemotherapeutic agents will be tested. If Cu-TA sensitizes NB cells to chemotherapy, it will help to address the issues associated with the side effects of chemotherapy.

Citation Format: Yazmin Hernandez, Sarah Sarah Grebennikov, Emily Zakhary, Ashni Dudhia, Rajasekhar Maram, Diego Casanova, Umesh T. Sankpal, W. Paul Bowman, Deondra T. Brown, Jaya Chhabra, Alvin A. Holder, Riyaz M. Basha. Antiproliferative effect of copper complex of clotam in neuroblastoma cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2881.