Creatine kinase BB and other markers of prostatic carcinoma

Creatine kinase BB has been described to be elevated in the serum of patients with prostate cancer. The incidence of abnormal serum levels correlates with the degree of differentiation of the tumor; that is, the more poorly differentiated tumors are associated most frequently with elevated CK-BB levels. We have recently described two additional findings which involve CK-BB in prostate cancer: 1) the finding of abnormally migrating CK-BB bands reported to be IgG-CK-BB complexes in several Stage D patients and in 2/3 Stage B patients following 125I implants, and 2) significant differences between CK-BB purified from prostatic fluid from CK-BB of brain origin. In particular, we find two bands of prostatic CK-BB following purification as compared to a single band from brain, when the same purification protocol is used. While further characterization of these differences is proceeding, the two bands of CK-BB are being used to develop a prostate-specific antiserum for use in immunoassays to detect prostate cancer in conjunction with other traditional markers such as prostatic acid phosphatase. If serum detection of tumor markers is to be efficacious, tumor marker panels such as CK-BB and prostatic acid phosphatase may provide a significant advantage over individual markers.