Interleukin-28B Plays a Therapeutic Role on Mouse U14 Cervical Cancer Cells by Down-Regulating CD4+CD25+FoxP3+Regulatory T Cells In Vivo.

ABSTRACT

AIM: To investigate the immunotherapeutic effectiveness of adenoviral vector expressing mouse interleukin (IL)-28B (Ad-mIL-28B) against cervical cancer and its mechanism. METHOD: U14 cervical cancer cell-bearing mice were treated with Ad-mIL-28B. Meanwhile, whole cell vaccine was prepared by repeated freezing and thawing U14 cells. Then CD4⁺CD25⁺FoxP3⁺regulatory T (Treg) cells were evaluated by flow cytometry. Tumor volume and metastasis in BALB/c and C57BL/6j mice were detected. RESULTS: Ad-mIL-28B treatment significantly decreased the number of CD4⁺CD25⁺FoxP3⁺Treg cells. Subsequently, there was a significant decrease in the size of tumor tissue and the numbers of heteromorphic tumor cells. The tumor metastasis in the lung and liver of the Ad-mIL-28B group also decreased. However, there was no therapeutic effect observed for whole cell vaccine on U14 tumor-bearing mice. CONCLUSION: Interleukin-28B can inhibit the growth and metastasis of cervical cancer in U14 tumor-bearing mice by down-regulating Treg cells.