Prostate cancer tumor markers

PSA is one of the most promising tumor markers of this decade. It is one of the few organ-specific tumor markers. Prostate cancer is the leading cancer in older men. When detected early (organ confined), it is potentially curable by radical prostatectomy. Therefore early detection is important. The role of PSA in prostate cancer has been reviewed. ... 

Intervention trials confirmed this protective role of lycopene on prostate cancer risk. Three primary intervention studies evaluated the effect of lycopene supplementation on prostate cancer risk or on certain risk markers such as prostate-specific antigen (PSA) plasma concentration or oxidative alterations of leucocyte DNA. - All showed increases of plasma and prostate lycopene levels after diet supplementation with lycopene and inverse correlations between tumor incidence and risk biomarkers. 

Patients must be monitored to assess their response to treatment and to detect recurrent diseases. PSA as a specific marker for prostate cancer is most useful in monitoring patients who have been treated with radical prostatectomy, radiation therapy, or endocrine therapy. The concentration of PSA falls to undetectable levels following a radical prostatectomy because all prostate tissue has been removed. Generally, PSA is measured at periodic intervals. In studies, the extent of disease at the time of surgery correlated well with the postoperative PSA concentration. A significant measurable PSA concentration after prostatectomy indicates that residual tumor may be present. PSA concentrations decline gradually after radiation therapy (36). 

Fixemer, T., Wissenbach, U., Flockerzi, V. and Bonkhoff, H., 2003, Expression of the Ca2+-selective cation channel TRPV6 in human prostate cancer a novel prognostic marker for tumor progression. Oncogene 22, 7858-61. 

Prostate-specific antigen (PSA, hK3) and, more recently, human glandular kallikrein 2 (hK2) are used as tumor markers for prostate cancer. Several... 

Prostate-cancer serum-tumor marker (PSA) 2000 C Factor 1000 Immuno-RCA 0.3 amol (0.1 pg/ml) ELISA 300 amol Schweitzer et al. [44], Immuno-RCA (see Section 2.1.3)... 

With few exceptions, an increase in the activity or mass of an enzyme or isoenzyme is not specific or sensitive enough to be used for identifying the type of cancer or the specific organ involvement. An exception is PSA. PSA has mild protease activity and amino acid sequence homology with serine protease of the kallikrein family.It is expressed by normal, benign, hyperplastic, and cancerous prostate glands and minimally by other tissue. Until the application of PSA as a marker for prostate cancer, tumor enzymes had lost most of their popularity for use as cancer markers. Enzymes were used historically as tumor markers before the discovery of oncofetal antigens and the advent of monoclonal antibodies. The abnormalities of enzymes as a marker for cancer are either the expression of the fetal form of the enzyme (isozyme) or the ectopic production of enzymes. 

Elevated levels of CKl have been demonstrated in prostate cancer and small cell carcinoma of the lung. Although it is also elevated in other malignancies, such as those of the breast, colon, ovary, and stomach, the clinical usefulness of CKl as a tumor marker requires further investigation. CK isoenzymes have been included in a prostate cancer panel, ProstAsure. ... 

PSA is an extremely useful tumor marker for prostate cancer. It is used to detect and stage the cancer and to monitor treatment of prostate cancer. It is also thought to be involved in tumor progression. 

Miki J., Furusato B., Li H., et al. (2007) Identification of putative stem cell markers, CD 133 and CXCR4, in hTERT-immortalized primary nonmalignant and malignant tumor-derived human prostate epithelial cell lines and in prostate cancer specimens. Cancer Res., 67, 3153-61. 

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