In addition, the serum RLN2 or relaxin level has been well examined and is reported to have some benefit as a predictive marker for malignant features, such as metastasis, and for prognosis for several types of cancer, including prostate [45], ovarian [46], esophageal [47], breast [48], and osteosarcoma [49]. The gene discussed is RLN2; the disease is cancer.