Abstract: Methods for diagnosing cancer, such as prostate, ovarian or breast cancer, as well as leukemia, are provided. Such methods may employ binding agents, such as antibodies or CAR sequences of OB-cadherin or N-cadherin, that specifically bind to OB-cadherin or N-cadherin, or polynucleotides that hybridize to a polynucleotide encoding OB-cadherin or N-cadherin. Also provided are methods for monitoring the progression of a cancer and to evaluate the metastatic potential of a cancer.