No abstract

Lung cancer has very high mortality and glycyrrhizin was found to significantly inhibit the growth of lung cancer cells in vitro and tissues in mice. However, the detailed inhibitory role of glycyrrhizin in the growth of lung cancer is still unclear. In this study, we first found that glycyrrhizin inhibited the growth of lung tumor in PDX mice. And high level of HMGB1 promoted the migration and invasion of lung cancer cells, which was suppressed by glycyrrhizin. Moreover, glycyrrhizin reduced the activity of JAK/STAT signaling pathway, which is the upstream regulator of HMGB1. Therefore, this study revealed a potential mechanism by which glycyrrhizin can inhibit the progression of lung cancer.

No abstract

Norcantharidin has been used as an efficacious anticancer drug in China for many years, but its true mechanism remains poorly understood. Intriguingly, in an in vitro series study of anticancer drugs, we found that norcantharidin can effectively inhibit epithelial tumor cells from expressing integrin avb6. Our previous studies have confirmed that integrin avb6 is closely relevant to malignant epithelial cell tumor biology behavior, and it can promote cancer cells to invade and metastasize through a special avb6-extracellular signal-related kinase (ERK) direct signaling pathway. In this study, we investigated the relationship between the norcantharidin anticancer mechanism and integrin avb6. After HT-29 colon cancer cells were treated with norcantharidin, cell apoptosis increased remarkably. The expression of avb6 and the amount of p-ERK decreased substantially; simultaneously, the linkage between avb6 and ERK was barely detectable. However, the expression of other integrins and the levels of mitogen-activated protein kinase hardly changed. On these grounds, we presumed that norcantharidin induced HT-29 colon cancer cell apoptosis through the avb6-ERK signaling pathway. This finding elicited a novel strategy for targeting the whole avb6-ERK signal pathway, rather than simply blocking the combining site of avb6-ERK in colon cancer treatment. (Cancer Sci 2009; 100: 2302-2308