Supramolecular assembly composed of different mesogenic compounds possessing a ω-hydroxyalkyl unit exhibits suppressive effects on the A549 human lung cancer cell line

Abstract

We investigated the anti-tumor activity and mesogenic properties of 4-cyano-4′-(6-hydroxyhexyloxy)biphenyl (I-CN), 4-methyloxy-4′-(6-hydroxyhexyloxy)biphenyl (I-OMe) and their binary mixtures. The anti-tumor properties of the materials were investigated in A549 human lung cancer cells by assessing cell growth, cell cycle distribution and cell signaling pathways using flow cytometry and Western blot analysis. An equimolar mixture of I-CN (2.5 μM) and I-OMe (2.5 μM) exhibited stronger inhibition of cell proliferation in A549 human lung cancer cells than I-CN or I-OMe. The mixture did not affect cell proliferation against WI-38 normal fibroblasts. Both thermotropic and lyotropic mesogenic properties of the mixture indicate that molecular aggregation between I-CN and I-OMe occurs at a concentration of micromolar order. These results reveal that the supramolecular assembly composed of different molecules plays an important role in the biological activity of liquid-crystalline molecules.