Effects of iodine-125 seeds on the methylation of SFRP2and P16 in colorectal cancer.
The current study investigated the effects of iodine-125 seeds on the gene methylation of SFRP2and P16 in colorectal cancer. Mouse models of human colorectal cancer were randomly divided into an experimental group (n=25) and a control group (n=25). The control group was implanted with blank seeds (0 MBq) and the experimental group with iodine-125 seeds (14.8 MBq). At 20 days after implantation, the animals were sacrificed. The methylation levels of SFRP2and P16 were detected using methylation-specific polymerase chain reactions (MSPs). Following iodine-125 seed irradiation, the level of SFRP2methylation decreased. The methylation index of the experimental group (0.67±0.05) was significantly lower than that of the control group (0.84±0.07; P<0.05). In the experimental group, 10 samples (40%) displayed methylation in the P16 promoter region compared with 14 (56%) in the control group, which was a significant difference (P<0.05). Iodine-125 seeds induce the downregulation of methylated tumor suppressor gene promoters, thereby inhibiting the proliferation and growth of tumor cells.
Departments of General Surgery, The Fourth Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650021, P.R. China.
Xiaogang
X
Li
Ping
P
Lu
Bo
B
Li
Wangfu
W
Zhang
Kaiyuan
K
Luo
P16; SFRP2; colorectal cancer; iodine-125 seeds; methylation