A similar study was conducted by Sun et al. in 1997 [34], who found that PTI-1 (prostate tumor inducing gene-1) is differentially expressed in the blood in patients with prostate cancer versus those with benign prostatic hypertrophy or a normal prostate and that serum PTI-1 levels can predict the tumor volume, though there was only one cancer cell present in 108PTI-1-negative cells. This evidence concerns the gene EEF1A1 and cancer.