Article Figures & Data
Figures
- Figure 1.
Methylation specific polymerase chain reaction (MSP) analysis results. Methylation status of p14ARF, p16INK4A (A) and SCARA5 (D) in the five CRC cell lines before and after 5-aza-2’ deoxycytidine (5-aza-dC) treatment, showing promoter demethylation after treatment. Representative MSP results in 15 CRC cell lines (B) and 23 pairs of primary colorectal tumor (Tumor) and normal epithelium (Normal) (C). M and U denote the presence of PCR product using primers specific for methylated and unmethylated sequences, respectively. Fully methylated and unmethylated human genomic DNA (HCT15 cell line and genomic DNA from whole blood in (A)) were used as positive controls (+ve) for methylated and unmethylated DNA, respectively. Reactions that contained no template DNA were used as a negative control (–ve). The expected size of the amplicon in base pairs is indicated on the right side of the panels.
- Figure 2.
Outline of selection of candidate genes in CRC.
- Figure 3.
Heatmap showing expression of the 16 candidate genes in CRC based on microarray analysis. The panels show fold change in gene expression after 5-aza-dC treatment compared to mock-treated cells (left), and overexpression in normal epithelium in comparison to CRC tumor tissues (right). Rows represent individual genes and columns represent individual CRC cell lines (left), and normal and tumor tissue samples (right). In each panel, the fold change is depicted according to the color score shown at the bottom right. Genes selected for validation in this study are indicated by bold letters.
- Figure 4.
Boxplot showing markedly reduced expression of SCARA5 in CRC. SCARA5 mRNA expression in 14 CRC cell lines and 14 paired tissue samples determined by RTQ-PCR. β-Actin was used as a reference gene. CRC cell lines and tumor tissue samples had lower SCARA5 expression than normal epithelium (p<0.001 and p=0.001, respectively); there was also a significant decrease in expression in CRC cell lines compared to tumor tissues (p<0.001). P-values were calculated by Wilcoxon signed ranks test for paired samples or Mann-Whitney test for unpaired samples.
