Lysophosphatidic Acid Triggers Apoptosis in HeLa Cells through the Upregulation of Tumor Necrosis Factor Receptor Superfamily Member 21

Figure 6

ERK and CREB pathway regulates LPA-induced DR6 expression. (a) HeLa cells were treated with LPA (25 μM) at various concentrations as indicated. The phosphorylation of MEK, ERK, and CREB was analyzed by Western blotting. The blot is a representative of 3 independent experiments (). (b and c) HeLa cells were treated with LPA in the presence of control siRNA and ERK- or CREB-specific siRNAs. The expressions of DR6 mRNA (b) and protein (c) were measured by q-PCR and Western analysis, respectively. The bar graphs on the right panel of (c) are statistical analysis of DR6 expression. Data presented are mean ± SD from 3 independent experiments, with nontreated controls set as 1. versus control; versus LPA/control siRNA.

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