Impact of calcium ion on cytotoxic effect of the boroxine derivative, K₂[B₃O₃F₄OH]

Abstract

The effect of Ca²⁺ ions on the cytotoxic ability of boron heterocyclic compound dipotassium-trioxohydroxytetrafluorotriborate (K₂[B₃O₃F₄OH]), on in vitro tumor cells (mammary adenocarcinoma 4T1, melanoma B16F10 and squamous cell carcinoma SCCVII) and non-tumoral fibroblast cells (mouse dermal L929 and hamster lung V79) was examined. At small concentrations of Ca²⁺ ions (0.42 mM), K₂[B₃O₃F₄OH] (3.85 mM) has a very strong cytotoxic effect on all cancer cells tested (89.1, 85.6 and 84.6%) and significantly less effect on normal cells (19.5 and 24.2%), respectively. Applying larger concentrations of Ca²⁺ ions (9.42–72.42 mM), at the same concentration of K₂[B₃O₃F₄OH], no significant cytotoxic effect was detected on cancer cells and normal cells investigated. The selective ability of K₂[B₃O₃F₄OH], in the medium with a low concentration of Ca²⁺ ions has a strong cytotoxic effect on cancer cells and very weak effect in normal cells, opens up the possibility of its application in antitumor therapy.

Keywords:

• Anticancer activity
• boroxine
• calcium ion
• drug research

Declaration of interest

This work has been fully supported by the Croatian Science Foundation under the project number (IP-2014-09-6897). The authors report no conflict of interest.