Doxycycline as an Inhibitor of the Epithelial-to-Mesenchymal Transition and Vasculogenic Mimicry in Hepatocellular Carcinoma
Menée à l'aide de xénogreffes de cellules de carcinome hépatocellulaire sur des modèles murins, cette étude met en évidence des mécanismes par lesquels, en inhibant la transition épithélio-mésenchymateuse, la doxycycline prolonge la survie des animaux
This study was conducted to examine the effects of doxycycline on the survival time and proliferation of hepatocellular carcinoma (HCC) in vivo and on the biological functions of HCC in vitro. This study was also designed to evaluate the effects of doxycycline on epithelial-to-mesenchymal transition (EMT)- and vasculogenic mimicry (VM)-related protein expression and on matrix metalloproteinase (MMP) and DNA methyltransferase (DNMT) activity in vitro. Human MHCC97H cells were injected into BALB/c mice, which were divided into treatment and control groups. Doxycycline treatment prolonged the mouse survival time and partly suppressed the growth of engrafted HCC tumor cells, with an inhibition rate of 43.39%. Higher amounts of VM and endothelium-dependent vessels were found in the control group than the treatment group. Immunohistochemistry indicated that epithelial (E)-cadherin expression was increased in the doxycycline-treated mice compared with the control group. In in vitro experiments, doxycycline promoted HCC cell adhesion but inhibited HCC cell viability, proliferation, migration, and invasion. Western blots, semi-quantitative RT-PCR, quantitative real-time PCR, and immunofluorescence demonstrated that doxycycline inhibited the degradation of the epithelial marker E-cadherin and downregulated the expression levels of EMT promoters, the mesenchymal marker vimentin, and the VM-associated marker vascular endothelial (VE)-cadherin. Furthermore, the activities of MMPs and DNMTs were examined in different groups via gelatin zymography and a DNMT activity assay kit. A methylation-specific polymerase chain reaction (MSP) was performed to assess the promoter methylation of CDH1 (the gene encoding E-cadherin). Doxycycline prolonged the mouse survival time by inhibiting EMT progression and VM formation.
http://mct.aacrjournals.org/content/early/2014/10/02/1535-7163.MCT-13-1060.abstract