探究乳腺癌组织中DACT2基因启动子甲基化与乳腺浸润性导管癌细胞生物学特性的关系。

2018年2月至2019年12月获取20例正常乳腺组织设为正常乳腺组(取自体检需要进行乳腺活检者)、60例乳腺癌旁组织设为乳腺癌旁组、60例乳腺癌组织设为乳腺癌组。应用RT-PCR技术检测三组DACT2 mRNA表达情况，DACT2甲基化技术检测DACT2甲基化状态，Transwell实验检测侵袭转移情况。采用SPSS20.0统计分析软件进行处理；计量资料采用(±s)表示，组间比较采用LSD-t检验；计数资料采用百分率(%)表示，组间比较采用χ²分析；P<0.05表示差异有统计学意义。

乳腺癌组中DACT2基因甲基化阳性率较乳腺癌旁组和正常乳腺组高(P<0.05)。乳腺癌旁组与正常乳腺组组织中DACT2基因甲基化发生率差异无统计学意义(P>0.05)。在乳腺癌甲基化中DACT2基因mRNA相对表达量低于非甲基化组(P<0.05)。乳腺癌组织出现不同程度的胞膜表达缺失。体外侵袭转移试验检测乳腺癌组织细胞的侵袭转移能力发现，乳腺癌组织中DACT2基因启动子甲基化高的模型组的细胞迁移能力上调(P<0.05)。乳腺癌组织中DACT2基因启动子甲基化低的模型组的细胞凋亡上调(P<0.05)。

抑制乳腺癌组织中DACT2基因启动子甲基化可降低乳腺浸润性导管癌细胞侵袭和转移，同时上调其凋亡。

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.