Effect of STAT1 on radiosensitivity of renal clear cell carcinoma / 中华放射肿瘤学杂志

ABSTRACT

Objective To study the expression of signal transducer and activator of transcription 1 (STAT1) in human renal clear cell carcinoma (RCC) and the effect of STATI inhibition on the radiosensi-tivity of RCC. Methods The expression of STAT1 in 34 human RCC samples compared with 12 normal kid-ney tissues was examined by immunohistochemistry method. For in vitro experiments, a human RCC cell line, CRL-1932, was used. Western blotting was performed to evaluate the expression of total and phospory-lated STAT1. Fludarabine and siRNA were respectively used to inhibit the expression of STAT1 in CRL-1932 cells. Clonogenic assay and trypan blue staining assay were used to evaluate the radiosensitivity of CRL-1932 cells. Results The expression of both total and phospborylated STAT1 in human RCC samples was signifi-cantly higher when compared to normal kidney tissues. Similarly, the expression of STAT1 was higher in CRL-1932 cells when compared to fibroblast and Wilm's tumor cell lines. STAT1 expression was inhibited by both fludarabine and siRNA. Radiosensitivity of CRL-1932 cells was enhanced by both fludarabine and siRNA induced STAT1 inhibition. Conclusions STAT1 is over-expressed in both human RCC tissue and cell line. Inhibition of STAT1 can enhance the radiosensitivity of RCC cells.