IGF1 and prostate cancer: When IGFBP-1 was added back to the exercise serum, lymph node cancer of the prostate growth was reduced and apoptosis was increased.109 Although serum in these aforementioned experiments was obtained from healthy males, a recent study expanded these methods to prostate cancer.71 A sample of 13 prostate cancer survivors on ADT performed 6 months of RT, which was found to significantly increase serum IGFBP-3 and reduce IGF-1:IGFBP-3 ratio in comparison with a control group.