Functional Analysis of the Action of Plant Isothiocyanates: Cellular Mechanisms and In Vivo Role in Plants, and Anticancer Activity

Abstract

Isothiocyanates are plant phytochemicals produced by Brassicales for protection against herbivores and pathogens. Recent studies have also suggested that these compounds may trigger internal defense responses. However, the cellular events triggered by isothiocyanates in plants remain elusive. In the present thesis, novel cellular mechanisms induced by isothiocyanates in Arabidopsis thaliana are reported, including disintegration of microtubules, attenuation of actin-mediated intracellular transport, depletion of glutathione, induced gene expressions and shift in the cell cycle. Isothiocyanates are also known to have chemopreventive properties against some types of cancer. Gastric cancer is a disease in great need of new treatment modalities. In the present thesis, the effects of isothiocyanates on human gastric cancer cells were studied. The present data shows that isothiocyanates inhibit the cell proliferation and migration, and induce cell cycle arrest and apoptosis in human gastric cancer cells. Moreover, isothiocyanates induce disintegration of microtubules in these cells. Collectively, the findings in this thesis shed light on the emerging field of in vivo role of isothiocyanates in plants, as well as the underlying molecular events of a potent natural therapeutic agent against gastric cancer.