Development of an enzyme-linked immunosorbent assay (ELISA) for the specific detection of MEKK1 expression in cells

Introduction: MEKK1 is a 196-kDa serine-threonine kinase activated in response to a variety of stimuli, including EGF, lysophosphatidic acid, osmotic stress, UV light, and microtubule toxins. However, there are few reports about the expression level of MEKK1 in cancers. Methods: In this report, a direct competitive ELISA to quantify total MEKK1 in cell lines was developed. Results: The procedure showed a high sensitivity (detection limit: 0.17 ng/ml), good precision (coefficient of variation ≤10.12) and acceptable linearity over a large range of MEKK1 concentrations (0.1-10,000 ng/ml). In a pilot study, this assay was used to quantify MEKK1 in different cell lines. In cancer cells, the range of MEKK1 is 0.02-85 ng/mg protein and its concentration was higher in pancreas cancer cells and umbilical vein cells than that in others. Discussion: This method can be used to measure the MEKK1 level of cell samples. The activity of MEKK1/JNK pathway in pancreas cancer and umbilical vein cell lines indicates that MEKK1 may be a potential target in interfering with pancreas cancer and angiogenesis.