STAT3 and Familial prostate cancer: In LNCaP and C4-2, two human prostate cancer cell lines, the expression of STAT3 protein is not affected in response to individual knockdown of EAF2 or p53 but significantly increases after EAF2 and p53 double-knockdown; conversely, although double deficiency of EAF2 and p53 elevates proliferation in C4-2 cells, it is suspended by knockdown of STAT3.