Inhibition of Tumor-Induced Angiogenesis and Matrix-Metalloproteinase Expression in Confrontation Cultures of Embryoid Bodies and Tumor Spheroids by Plant Ingredients Used in Traditional Chinese Medicine

Abstract

SUMMARY:Tumor-induced angiogenesis is a prerequisite for excessive tumor growth. Blood vessels invade the tumor tissue after degradation of the extracellular matrix scaffold by matrix metalloproteinases (MMPs). Inhibition of MMPs has been therefore suggested to be a useful tool to abolish neoangiogenesis of solid tumors. In the present study, antioxidative plant ingredients used in traditional Chinese medicine were investigated for their capacity to down-regulate MMP expression and to inhibit angiogenesis in embryonic stem cell-derived embryoid bodies and tumor-induced angiogenesis in confrontation cultures consisting of embryoid bodies and multicellular DU-145 prostate tumor spheroids. Embryoid bodies transiently expressed MMP-1, MMP-2, and MMP-9 during the time of differentiation of capillary-like structures. In confrontation cultures, MMP expression was increased compared with control tumor spheroids and embryoid bodies cultivated separately. The increased expression of MMPs in confrontation cultures was a result of elevated levels of reactive oxygen species (ROS) upon confrontation culture and was totally abolished in the presence of the free radical scavenger vitamin E. Incubation of embryoid bodies with baicalein, epicatechin, berberine, and acteoside, which are herbal ingredients used in traditional Chinese medicine, significantly inhibited angiogenesis in embryoid bodies and decreased intracellular ROS levels. Tumor-induced angiogenesis in confrontation cultures was totally abolished in the presence of the free radical scavenger vitamin E. Because herbal ingredients down-regulated MMP expression, we conclude that ROS generated during confrontation culture induce the expression of MMPs that are necessary for endothelial cell invasion into the tumor tissue. (Lab Invest 2003, 83:87-98).

Berberine suppresses proinflammatory responses through AMPK activation in macrophages

“…Previously, it has been shown that BBR functions as a ROS scavenger in embryoid bodies and vascular smooth muscle cells (8,50). Consistent with this, we observed that BBR reduced ROS production in macrophages and revealed that AMPK activation is essential for the inhibitory effect of BBR on ROS generation in macrophages.…”

“…It has been well established that proinflammatory stimuli such as LPS and TNF-␣ promote an early and acute increase of cellular ROS levels (13,21) that stimulate MAPK cascade and downstream transcriptional factors to mediate inflammatory responses (13,21,50). On the other hand, it is also known that inflammatory molecules such as IFN-␥ and LPS rapidly activate classical MAPK kinase pathways, implying that both ROS and MAPK signaling appear to augment each other during inflammatory responses (5).…”

The Antimalaria Agent Artemisinin Exerts Antiangiogenic Effects in Mouse Embryonic Stem Cell-Derived Embryoid Bodies

“…However, in the artemisinin-treated sample, a significant increase in MMP-2 expression was observed from Day 6 to Day 8 of cell culture (n ϭ 3)-Day 6: 504 Ϯ 21%, Day 7: 609 Ϯ 34, and Day 8: 623 Ϯ 5 in the artemisinin-treated sample versus Day 6: 281 Ϯ 23%, Day 7: 391 Ϯ 11, and Day 8: 500 Ϯ 18 in the control. As previously shown (Wartenberg et al, 2003a) endogenous MMP-9 expression was lower as compared with MMP-1 and MMP-2 but increased during the time course of embryoid bodies culture to 238 Ϯ 10% (immunofluorescence at Day 4 set to 100%) (n ϭ 3). In contrast, treatment with 50 M artemisinin resulted in significantly elevated MMP-9 expression at Day 4 of embryoid body culture (308 Ϯ 13%), which decreased to 128 Ϯ 15% on Day 8 of embryoid body culture (n ϭ 3).…”

Potential Therapeutic Molecular Targets for Nasopharyngeal Carcinoma

“…Other signaling pathways have also been shown to be required for berberine-induced apoptosis, including the JNK/p38 MAPK (111), p53-dependent ATF3 (235), ER stress (172), and NF-B pathways (227). In addition to apoptosis induction, berberine has also shown potent anti-angiogenic effects on the inhibition of tumor-induced angiogenesis and MMP-1, -2, and -9 expression (313). Berberine inhibits the invasion of human lung cancer A549 cells in vitro by decreasing the production of the urokinase-plasminogen activator and MMP-2 (234).…”