Cag+ H. pylori strain 60190 at an MOI of 100:1 for the Hesperidin site indicated time points. (A) Quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (B) Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. (C) Western blot analysis replicates were quantified using densitometry. (D) Gastric epithelial cells were either left untreated or pretreated with actinomycin D for 1 hour prior to co-culture with H. pylori. Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. Data are represented as fold over uninfected control. 2 and + symbols indicate the absence or presence of H. pylori (Hp), respectively. Error bars indicate standard error of the mean from experiments performed on at least three independent occasions, and Mann-Whitney tests were used to determine statistical significance between groups. doi:10.1371/journal.pone.JSI124 chemical information 0054344.gKLF5 and H. Pylori-Mediated Gastric CarcinogenesisFigure 2. H. pylori-induced KLF5 upregulation is independent of the cag pathogenicity island, VacA, or LPS. AGS human gastric epithelial cells were co-cultured with wild-type cag+ H. pylori strain 60190, or its isogenic cagE2, cagA2, slt2, or vacA2 mutants at an MOI of 100:1 for 2 hours. (A) Quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (B) Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. (C) Western blot analysis replicates were quantified using densitometry. (D) Gastric epithelial cells were cocultured with the wild-type cag+ H. pylori strain 60190, heat-killed (HK) H. pylori strain 60190, or with strain 60190 in a transwell (TW) system for 2 hours and quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (E) Gastric epithelial cells were treated with H. pylori LPS (10 ng/ml or 100 ng/ml) for 2 hours and quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. Data are represented as fold over uninfected (UI) control. Error bars indicate standard error of the mean from experiments performed on at least three independent occasions, and Mann-Whitney tests were used to determine statistical significance between groups. doi:10.1371/journal.pone.0054344.gBiosciences), a rabbit polyclonal anti-Lrig1 antibody (1:200, [24]), and a murine goat polyclonal anti-KLF5 antibody (1:50, Santa Cruz Biotechnology) at room temperature for 20 minutes. Cells were washed and stained with hamster anti-rabbit secondary antibody conjugated with fluorescein isothiocyanate (FITC, 1:400, BD Biosciences) and 23977191 donkey anti-goat secondary antibody conjugated with phycoerythrine (PE, 1:200, BD Biosciences). Cells were acquired using a LSR II Flow Cytometer (BD Biosciences) and pancytokeratin-positive cells were analyzed for KLF5 and Lrig1 expression by using FlowJo (Tree Star Inc.).Immunohistochemistry on human gastric mucosaThe Institutional Review Board (IRB) of Louisiana State University Health Sciences Center, the Committees on Ethics of Universidad del Valle and Hospital Departamental de Narino in Colombia, and the Institutional Review Board (IRB) of Vanderbilt University Medical Center approved this protocol. Gastric antrum biopsy samples from patients residing in a high gastric cancer risk region in the Colombian Andean mountains, who were enr.Cag+ H. pylori strain 60190 at an MOI of 100:1 for the indicated time points. (A) Quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (B) Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. (C) Western blot analysis replicates were quantified using densitometry. (D) Gastric epithelial cells were either left untreated or pretreated with actinomycin D for 1 hour prior to co-culture with H. pylori. Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. Data are represented as fold over uninfected control. 2 and + symbols indicate the absence or presence of H. pylori (Hp), respectively. Error bars indicate standard error of the mean from experiments performed on at least three independent occasions, and Mann-Whitney tests were used to determine statistical significance between groups. doi:10.1371/journal.pone.0054344.gKLF5 and H. Pylori-Mediated Gastric CarcinogenesisFigure 2. H. pylori-induced KLF5 upregulation is independent of the cag pathogenicity island, VacA, or LPS. AGS human gastric epithelial cells were co-cultured with wild-type cag+ H. pylori strain 60190, or its isogenic cagE2, cagA2, slt2, or vacA2 mutants at an MOI of 100:1 for 2 hours. (A) Quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (B) Western blot analysis was used to assess KLF5 protein expression relative to GAPDH protein expression. (C) Western blot analysis replicates were quantified using densitometry. (D) Gastric epithelial cells were cocultured with the wild-type cag+ H. pylori strain 60190, heat-killed (HK) H. pylori strain 60190, or with strain 60190 in a transwell (TW) system for 2 hours and quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. (E) Gastric epithelial cells were treated with H. pylori LPS (10 ng/ml or 100 ng/ml) for 2 hours and quantitative real-time RT-PCR was used to assess KLF5 mRNA expression relative to GAPDH mRNA expression. Data are represented as fold over uninfected (UI) control. Error bars indicate standard error of the mean from experiments performed on at least three independent occasions, and Mann-Whitney tests were used to determine statistical significance between groups. doi:10.1371/journal.pone.0054344.gBiosciences), a rabbit polyclonal anti-Lrig1 antibody (1:200, [24]), and a murine goat polyclonal anti-KLF5 antibody (1:50, Santa Cruz Biotechnology) at room temperature for 20 minutes. Cells were washed and stained with hamster anti-rabbit secondary antibody conjugated with fluorescein isothiocyanate (FITC, 1:400, BD Biosciences) and 23977191 donkey anti-goat secondary antibody conjugated with phycoerythrine (PE, 1:200, BD Biosciences). Cells were acquired using a LSR II Flow Cytometer (BD Biosciences) and pancytokeratin-positive cells were analyzed for KLF5 and Lrig1 expression by using FlowJo (Tree Star Inc.).Immunohistochemistry on human gastric mucosaThe Institutional Review Board (IRB) of Louisiana State University Health Sciences Center, the Committees on Ethics of Universidad del Valle and Hospital Departamental de Narino in Colombia, and the Institutional Review Board (IRB) of Vanderbilt University Medical Center approved this protocol. Gastric antrum biopsy samples from patients residing in a high gastric cancer risk region in the Colombian Andean mountains, who were enr.