GNRH1 and cancer: Testing these GnRH-based chimeric proteins on different cancer cell lines, primary cultures, as well as in colon cancer models in mice [13,45], we were the first to report that a wide variety of solid tumors that are not part of the reproductive system, such as colon cancer, kidney cancer, and many other solid tumors, overexpress the GnRH-R/binding sites [16,28,33].