Characterization of phospholipase A2 activity in MDA-MB-435 human breast cancer cells.
Phospholipase A2 (PLA2) was identified and its properties characterized in MDA-MB-435 cells, a human breast cancer cell line. Cytosolic fractions, prepared in calcium-free buffer, were assayed using arachidonyl-containing phosphatidylcholine as substrate. PLA2 activity was linear as a function of both time and protein concentration. The enzyme was shown to be calcium-dependent and to require a basic pH of 9.5-10.0 for optimal activity. Activity was predominantly found in the cytosolic fraction when cells were harvested in calcium-free buffer. Phospholipase A2 may play a key role in linoleic acid-enhanced mammary tumorigenesis and metastasis.
Hatala
M A
MA
Division of Nutrition and Endocrinology, American Health Foundation, Valhalla, New York 10595.
Rayburn
J
J
Rose
D P
DP
D001943:Breast Neoplasms / Q000378:metabolism*; D002474:Cell-Free System; D005260:Female; D006801:Humans; D019787:Linoleic Acid; D008041:Linoleic Acids / Q000378:metabolism; D010741:Phospholipases A / Q000378:metabolism*; D054467:Phospholipases A2; D010743:Phospholipids / Q000737:chemistry; D014407:Tumor Cells, Cultured
D008041:Linoleic Acids; D010743:Phospholipids; D019787:Linoleic Acid; D010741:Phospholipases A; D054467:Phospholipases A2