Transcript levels of ten-eleven translocation type 1-3 in cervical cancer and non-cancerous cervical tissues

Abstract

Decreased expression of ten-eleven translocation (TET1, TET2 and TET3) proteins has been reported in various types of cancer. However, the expression levels of TET proteins in cervical cancer (CC) remain to be elucidated. The present study determined the levels of TET1, TET2 and TET3 transcripts in cancerous (n=80) and non-cancerous cervical tissues (n=41). The results revealed a significant reduction in TET1 transcripts (P=0.0000001) in cervical tissue samples from patients with primary CC compared with samples from control patients. Significantly decreased TET1 transcript levels, as compared to non-cancerous cervical tissues, were also observed in tissue samples with the following characteristics: Stage I (P=0.016), II (P<0.0001), III (P=0.00007) and grade of differentiation G1 (P=0.026), G2 (P=0.00006), G3 (P=0.0007) and Gx (P=0.0004) and squamous histological type (P<0.00001). TET1 transcript levels were significantly lower in patients aged 45-60 years (P=0.0002) and patients age >60 years (P=0.003), as compared with non-cancerous cervical tissues. TET2 transcript levels were lower in cervical cancer tissues classified as stage II (P=0.043) and TET3 transcript levels were lower in stage III samples (P=0.010), tissue samples with a grade of differentiation of G3 (P=0.025) and tissue with squamous type histology (P=0.047), all compared with non-cancerous cervical tissues. The present study demonstrated a significantly reduced level of TET1 transcripts in cancerous cervical tissues, as compared with non-cancerous tissues. Furthermore, decreased TET1-3 transcript levels were identified when patients with CC were stratified by clinicopathological variables, as compared with non-cancerous cervical tissues.

Keywords: cervical cancer; ten-eleven translocation 1-3.

Figure 1.

Comparison of TET1, TET2 and TET3 transcript levels in cervical cancer and non-cancerous tissue. CT was obtained from 80 patients with primary cervical cancer, and NCT were obtained from 41 women with uterine fibroids undergoing uterine surgical resection. Frozen tissue was homogenized and total RNA was isolated and reverse-transcribed to cDNA. The TET transcript levels for patients and controls were quantified by reverse transcription-quantitative polymerase chain reaction using the relative quantification method. The quantity of TET1, TET2 and TET3 transcripts in each sample was corrected to porphobilinogen deaminase cDNA levels and expressed as a multiplicity of these copies as a calibrator. The P-value was calculated using the Mann-Whitney test. P<0.05 was considered to be statistically significant. TET, ten-eleven translocation; CT, cancerous tissue; NCT, non-cancerous tissue.