Promoter Region Hypermethylation and mRNA Expression of MGMT and p16 Genes in Tissue and Blood Samples of Human Premalignant Oral Lesions and Oral Squamous Cell Carcinoma
Table 2
Methylation profile of MGMT and p16 genes in tissue and blood samples of study groups.
Gene methylation
Groups
Tissue
Blood
M*
U
P valuea
M*
U
P valuea
MGMT
Control ()
2 (13%)
14 (87%)
Ref
1 (6%)
15 (94%)
Ref
PMOLs ()
32 (59%)
22 (41%)
0.001
21 (39%)
33 (61%)
0.0135
PMOL subtypes
LKP ()
16 (73%)
6 (27%)
0.0002
9 (41%)
13 (59%)
0.0166
LKPD ()
8 (73%)
3 (27%)
0.0015
6 (55%)
5 (45%)
0.0049
SMF ()
6 (46%)
7 (54%)
0.0437
4 (31%)
9 (69%)
0.0821
OLP ()
2 (25%)
6 (75%)
0.4386
2 (25%)
6 (75%)
0.1904
OSCC ()
58 (76%)
18 (24%)
0.0001
43 (57%)
33 (43%)
0.0002
P valueb
PMOLs versus OSCC
—
—
0.0379
—
—
0.0468
p16
Control ()
2 (13%)
14 (87%)
Ref
0 (0%)
16 (100%)
Ref
PMOLs ()
31 (57%)
23 (43%)
0.0016
18 (33%)
36 (67%)
0.0074
PMOL subtypes
LKP ()
15 (68%)
7 (32%)
0.0007
10 (45%)
12 (55%)
0.0017
LKPD ()
4 (36%)
7 (64%)
0.1428
2 (18%)
9 (82%)
0.0763
SMF ()
8 (62%)
5 (38%)
0.0057
6 (46%)
7 (54%)
0.0023
OLP ()
4 (50%)
4 (50%)
0.0455
0 (0%)
8 (100%)
NA
OSCC ()
62 (82%)
14 (18%)
0.0001
53 (70%)
23 (30%)
0.0001
P valueb
PMOLs versus OSCC
—
—
0.0026
—
—
0.0001
M: methylated, U: umethylated, and Ref: reference; aChi-square test considering control as reference category; bChi-square test considering PMOLs as reference category.
*Methylated group includes samples showing complete methylation (only methylated amplicon) as well as samples showing partial methylation (both methylated and unmethylated amplicons).
