Cisplatin Induced the Expression of SEI1 (TRIP-Br1) Oncogene in Human Oral Squamous Cancer Cell Lines.

Abstract

Aberrant expression of the SEI1 oncogene has been prevalently found in a variety of human cancers, including oral squamous cell carcinoma (OSCC). Recent studies have shown that cisplatin up-regulates the expression of SEI1 in breast and bladder cancer cells, thus inhibiting apoptosis and cell death in these cells. In the present study, we investigated the impact of cisplatin on the expression of SEI1 in OSCC cells. Four OSCC cell lines, CAL27, SCC4, SCC15, and SCC22A were treated with cisplatin and 5-fluorouracil, and changes in SEI1 expression in these cells were evaluated using quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) analyses. Cisplatin significantly induced SEI1 expression in the tested OSCC cells. Contrarily, cisplatin treatment did not affect the expression of gankyrin and BMI1, two oncogenes frequently overexpressed in a coordinate manner with SEI1 in OSCC. Additionally, 5-fluorouracil did not bring about any detectable changes in SEI1 expression in these cells. Cisplatin-induced up-regulation of SEI1 expression in OSCC is specific, and such induction could underlie the development of resistance to cisplatin in OSCC.