PMC

Bisulfite sequencing of the GSTP1 promoter. Three representative sequences showed methylation status of cytosines at the target sites of MS-PCR primers. Methylated cytosines found in tumor cases remained unchanged as cytosines after bisulfite modification, whereas unmethylated cytosines were converted and sequenced as thymine.

The scatterplot showing overall distribution of the normalized results of the real-time quantitative RT-PCR assay. Each dot represented a normalized mRNA expression of GSTP1 for each of the sample cases, and the horizontal lines showed the mean values. Reduced expression of GSTP1 was observed in tumor tissues of endometrial carcinomas.

A: TMA was constructed containing 48 cases of endometrial carcinoma in each block. B and C: Immunohistochemical staining of the GSTP1 protein in endometrioid adenocarcinoma. Two representative cases showing reduced cytoplasmic and nuclear staining in tumor cells (T) compared with residual normal endometrial glands (NT) present. D: Strong immunoreactivity was observed in foci of squamous differentiation (Sq).

Representative results of MS-PCR on CpG clusters of GSTP1 promoter region. Horizontally, each panel represented one sample case showing results of the six MS-PCR reactions. PCR products of MSP1 to MSP5 were resolved on 2% agarose gel; whereas the product of MSP6 was resolved on 8% PAGE. Lanes U, amplification with primers recognizing unmethylated sequence; lanes M, amplification with primers recognizing methylated sequence. DNA treated with SssI methylase was used as a positive control.