Figure 4.

Decreased expression of PTEN in HGC-27 cells with CagA overexpression is reversed by Tet1 overexpression. HGC-27 cells were infected with viruses carrying CagA and/or a Tet1 overexpression vector. (A) mRNA expression levels of PTEN in the cells was detected by reverse transcription-quantitative PCR. (B) Western blot analysis was used to measure the protein expression levels of PTEN in the cells. (C) Methylation status of PTEN was detected by methylation-specific PCR in HGC-27 cells. ***P<0.001 vs. the negative control group; ^##P<0.01, ^###P<0.001 vs. the CagA overexpression group (n=3). M, methylated; PCR, polymerase chain reaction; PTEN, phosphatase and tensin homolog; Tet1, tet methylcytosine dioxygenase 1; U, unmethylated.