To explore the relationship between promoter methylation of DACT2 gene in breast cancer and biological characteristics of invasive ductal carcinoma cells.

From February 2018 to December 2019, 20 normal breast tissues were selected as normal breast group (from those who need breast biopsy due to physical examination), 60 cases of breast cancer adjacent tissues were selected as breast cancer adjacent group, and 60 cases of breast cancer tissues were set as breast cancer group. DACT2 mRNA expression was detected by RT-PCR, DACT2 methylation was detected by DACT2 methylation, and invasion and metastasis were detected by Transwell assay. SpSS20.0 statistical analysis software was used for processing; measurement data was expressed by (±s), and LSD-t test was used for comparison between groups; count data was expressed by percentage (%), and χ² analysis was used for comparison between groups; P<0.05 indicated statistically significant difference.

The positive rate of DACT2 gene in breast cancer group was higher than that in breast cancer group and normal breast group (P<0.05). There was no significant difference in the incidence of DACT2 gene between breast cancer group and normal breast group (P>0.05). The relative expression of DACT2 gene mRNA in breast cancer group was lower than that in non methylation group (P<0.05). There are different degrees of cell membrane expression loss in breast cancer tissue. The invasion and metastasis ability of breast cancer tissue cells was detected by in vitro invasion and metastasis test. It was found that the cell migration ability of the model group with high methylation of DACT2 gene in breast cancer tissues was upregulated (P<0.05). The apoptotic cells in the model group with low methylation of DACT2 promoter in breast cancer tissues were up-regulated (P<0.05).

Inhibition of methylation of DACT2 promoter in breast cancer tissue can reduce invasion and metastasis of breast infiltrating ductal carcinoma cells and increase its apoptosis.