In addition, these results indicate that a decrease in the activation of NF-κB induced by DMF in breast cancer cells plays an important role in the inhibition of EMT, Snail and Twist expression, migration, and invasion. Breast cancer often invades bone tissue, causing skeletal complications due to metastasis . In more than 75% of all breast cancer patients, bone metastasis was found at the time of autopsy . EMT is the first step that allows the extravasation and migration of carcinoma cells in the metastatic process. EMT entails the downregulation of E-cadherin and the upregulation of its suppressor, Snail and Twist, in carcinoma cells [5, 6, 10]. Resent studies
showed that Twist was frequently observed in the bone marrow of breast cancer patients and the expression of Twist correlated with the rapid occurrence of distant metastasis see more or local progression . It has been indicated that Snail-positive breast cancer tends to home into the bone in breast cancer patients . In addition, more than 80% of bone metastases from solid tumors, including EGFR inhibitor carcinoma and sarcoma, are RANK-positive, as revealed by immunohistochemistry [17, 21]. Moreover, it has been reported that inhibition of RANKL by recombinant osteoprotegerin, a decoy
receptor for RANKL, suppressed tumor bone metastasis and progression and improved survival in a mouse model . The present results clearly indicated that the RANKL/RANK system induced EMT via enhanced expression of Snail and Twist, and the activation of NF-κB. Collectively, these findings suggest that RANKL-induced EMT may play an important role in bone metastasis in RANK-expressing cancer cells. Conclusion In conclusion, our data show
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