Ras 转化和永生化人乳腺上皮细胞中的磷脂酶 A2

Phospholipases A2 in ras-transformed and immortalized human mammary epithelial cells.

作者信息

Guthridge C J, Stampfer M R, Clark M A, Steiner M R

机构信息

Department of Microbiology and Immunology, University of Kentucky, Lexington 40536.

出版信息

Cancer Lett. 1994 Oct 28;86(1):11-21. doi: 10.1016/0304-3835(94)90175-9.

DOI:10.1016/0304-3835(94)90175-9

PMID:7954346

Abstract

Phospholipase A2 (PLA2) activities of non-tumorigenic and tumorigenic human mammary epithelial cells, 184B5 cells (immortalized cell line from a reduction mammoplasty) and B5KTu cells (cells from a tumor induced by ras-transformed 184B5 cells), are characterized, with emphasis on lipid biomediator-related phospholipases A2. Phospholipases A2 associated with regulation of arachidonic acid metabolism include the high molecular mass cytosolic PLA2 (cPLA2) and group II PLA2. The major PLA2 activity in the mammary epithelial cells has the characteristics of cPLA2; this activity is higher in the B5KTu cells. In contrast, the 184B5 and B5KTu cells have similar levels of a Ca(2+)-independent, cytosolic PLA2 activity and low levels of a particulate fraction PLA2 activity, which does not have the properties of group II PLA2. Thus, cPLA2 activity is selectively elevated in the tumorigenic human mammary epithelial cells and this may result in increased generation of lipid biomediators such as arachidonic acid metabolites.

摘要

对非致瘤性和致瘤性人乳腺上皮细胞、184B5细胞（来自缩乳术的永生化细胞系）和B5KTu细胞（由ras转化的184B5细胞诱导产生的肿瘤细胞）的磷脂酶A2（PLA2）活性进行了表征，重点关注与脂质生物介质相关的磷脂酶A2。与花生四烯酸代谢调节相关的磷脂酶A2包括高分子量胞质磷脂酶A2（cPLA2）和II型磷脂酶A2。乳腺上皮细胞中的主要PLA2活性具有cPLA2的特征；该活性在B5KTu细胞中更高。相比之下，184B5和B5KTu细胞具有相似水平的不依赖Ca(2+)的胞质PLA2活性以及低水平的微粒体部分PLA2活性，后者不具有II型磷脂酶A2的特性。因此，cPLA2活性在致瘤性人乳腺上皮细胞中选择性升高，这可能导致脂质生物介质如花生四烯酸代谢产物的生成增加。