|
n = 52
|
Primary cancerous tissues
|
Histopathologically unchanged tissues
|
pa
|
|---|
| | |
Median (range)
|
Mean (± SD)
|
Median (range)
|
Mean (± SD)
| |
|---|
|
Age
| | | | | | |
|
<60
|
10
|
21.05 (12.89-25.79)
|
20.66 ± 4.205
|
19.47 (13.16-28.42)
|
19.32 ± 4.875
|
0.5181
|
|
>60
|
42
|
20.00 (4.211-33.16)
|
20.91 ± 7.074
|
18.95 (2.105-36.21)
|
18.42 ± 6.779
|
0.1076
|
|
Gender
| | | | | | |
|
Female
|
20
|
24.21 (16.84-33.16)
|
24.42 ± 4.516
|
23.68 (13.68-28.42)
|
21.75 ± 4.499
|
0.1155
|
|
Male
|
32
|
18.95 (4.211-32.11)
|
19.51 ± 7.255
|
17.37 (2.105-36.21)
|
18.43 ± 7.206
|
0.5594
|
|
CRC localization
| | | | | | |
|
Proximal colon (cecum to transverse)
|
20
|
24.21 ( 13.68-33.16)
|
23.54 ± 5.793
|
17.63 ( 2.105435.79)
|
17.61 ± 6.050
|
0.0030
|
|
Distal colon (splenic flexture to sigmoid)
|
12
|
19.47 (4.211-28.95)
|
19.69 ± 7.159
|
18.95 (10.53-25.26)
|
18.85 ± 4.747
|
0.7498
|
|
Rectum
|
20
|
19.47 (6.316-28.42)
|
19.36 ± 6.292
|
19.47 (4.737-36.21)
|
19.30 ± 7.851
|
0.9810
|
|
Histologic grade
| | | | | | |
|
G1
|
4
|
21.32 (13.68-28.42)
|
21.18 ± 8.067
|
17.89 (2.105-27.89)
|
16.45 ± 10.97
|
0.5126
|
|
G2
|
35
|
20.00 (10.53-30.53)
|
21.17 ± 5.293
|
19.47 (4.737-28.42)
|
18.93 ± 5.884
|
0.0996
|
|
G3
|
13
|
21.84 (4.211-33.16)
|
20.21 ± 9.397
|
15.53 (12.63-36.21)
|
18.11 ± 6.727
|
0.4021
|
- The primary cancerous and histopathologically unchanged tissue samples from the same patients were used for genomic DNA isolation, followed by bisulfite conversion of cytosine to uracil. The three DNA fragments of the CpG rich region were then amplified by three pairs of primers complementary to the bisulfite-DNA modified sequence (Additional file 1, Additional file 2). To determine the percentage of methylation, the HRM profiles of the patients' DNA PCR products were compared to HRM profiles of the prepared standard PCR products. DNA methylation for each patient was presented as a percentage of methylation in three DNA amplified fragments located in the CpG rich region (Additional file 1). a Unpaired, two-tailed t-test.
