LPS induces increased production of BTC and IL-8 in human lung cancer cells A549. A549 cells grown in complete medium were left untreated (control) or treated with LPS (0.01, 0.1 and 1 μg/ml) for 4 h. Total RNA was extracted and subjected to reverse transcription followed by qPCR to detect BTC (A) and IL-8 (C) mRNA, as described in Material and Methods. Data were normalized to control. A549 cells (1 × 105/ml) were stimulated with LPS for 24 h, then the cytokines including BTC (B) and IL-8 (D) in cell-free supernatants were assayed using sandwich ELISA. Each data point represents mean ± SEM of three experiments. * and ** stand for P -values less than 0.05 and 0.01, as compared to control.