[Human breast myoepithelial cell blocks estrogen receptor-negative breast carcinoma cell invasion].

OBJECTIVE

To investigate the effect of mammary myoepithelial cell on breast cancer cell infiltration.

METHODS

By immunohistochemistry, Western Blot, Northern Blot and Matrigel invasion experiments, we detected the maspin in breast cancer cell and myoepithelial cell, and studied the machanism of breast cancer cell invasion inhibition by myoepithelial cell.

RESULTS

Histologically, ducts and ductal carcinoma in situ (DCIS) were surrounded by an intact circumferential layer of myoepithelial cells. In invasive carcinoma, the myoepithelial cell layer appeared disrupted. In matrigel invasion experiments, myoepithel cell and its condition medium could block the ER-negative breast carcinoma cell line MDA-MB-231 cell invasion. The proteinase inhibitor most dramatically up-regulated in myoepithelial cells was the tumor suppressor maspin which was only highly expressed in myoepithelial cells, not in breast cancer cells.

CONCLUSION

Mammary myoepithelial cells could inhibit tumor cell invasion, suggesting that myoepithelial cell might have antitumor effect in the regulation of breast cancer development and progression in vivo.