Down-regulation of IFITM1 and its growth inhibitory role in cervical squamous cell carcinoma.

BACKGROUND: Cervical cancer is a major cause of death in women worldwide. Interferon-induced transmembrane protein 1 (IFITM1) is involved in antivirus defense, cell adhesion, and carcinogenesis in different tissues. However, the role of IFITM1 gene in cervical squamous cell cancer is unclear. METHODS: To explore the role of IFITM1 in carcinogenesis of cervical cancer, we investigated the expression of IFITM1 gene in cervical squamous cell carcinoma. IFITM1 mRNA level was measured by real-time quantitative RT-PCR in cervical cancer tissues and their adjacent normal tissues. IFITM1 protein level was measured by immunohistochemistry. Methylation in the IFITM1 gene promoter was detected by methylation-specific PCR. We then transfected HeLa cells with IFITM1 expression vector or control vector. IFITM1 expression was examined; cell migration and invasion were analyzed by wound healing assay and matrigel-coated transwell migration assays, respectively. HeLa cell proliferation was measured by cell counting kit-8 assay and cell cycle analysis. Cell apoptosis was analyzed by Annexin V/propidium iodide double staining assay. RESULTS: The difference in IFITM1 protein expression between samples from chronic cervicitis and cervical carcinoma was statistically significant (P < 0.01). Ki-67 and PCNA protein expression levels were significantly higher in cervical cancer tissues than in their corresponding cervicitis tissues (P < 0.05 and P < 0.001, respectively). IFITM1 mRNA level was significantly lower in cervical cancer tissues than in normal cervical tissues (P < 0.05). Methylation of the IFITM1 gene promoter was significantly higher in cervical cancer than in normal cervical tissues (P < 0.05). Transfection of the IFITM1 pcDNA3.1 construct decreased cell migration and invasion of HeLa cells, inhibited cell proliferation, and increased cell apoptosis. CONCLUSION: IFITM1 gene expression may reduce the proliferation, migration, and invasion of cervical squamous cancer cells.

Methylation in the promoters of HS3ST2 and CCNA1 genes is associated with cervical cancer in Uygur women in Xinjiang.

We assessed the suitability of HS3ST2 and CCNA1 genes as biomarkers for the early detection of cervical cancer in Uygur women in Xinjiang, China. Methylation-specific PCR (MSP) and HPV (HPV16 and HPV18)-specific PCR were performed on 110 cervical samples: 40 normal cervices, 10 cervical intraepithelial neoplasia 1 (CIN1), 10 CIN2, 10 CIN3 and 40 cervical cancer tissues. The expression of the 2 genes was measured by reverse transcription PCR (RT-PCR) in 10 methylation-positive and 10 methylation-negative cervical tissues. We found that both HS3ST2 and CCNA1 genes were methylated in 38 of the 40 cervical cancer tissues, 9 of the 10 CIN3, and 6 of the 10 CIN2. In contrast, methylation of these 2 genes was found in only 1 of the 40 normal tissues and none of 10 CIN1. Furthermore, hypermethylated HS3ST2 and CCNA1 genes were correlated with infection with HPV16 and HPV18 in high-grade squamous intraepithelial lesions (HSILs) and cervical cancer (both p<0.05). The expression of HS3ST2 and CCNA1 genes was lower in the methylation-positive cervical tissues than in the methylation-negative cervical tissues. Our results indicate that HS3ST2 and CCNA1 genes may play important roles in HPV-induced cervical cancer and that patients with specific hypermethylated genes may have a greater risk of progressing to invasive cervical cancer.