Granins and prostate cancer.
OBJECTIVE
The importance of the expression of granin A (GRN-A, chromogranin-A) has become appreciated in the neuroendocrine differentiation of prostate cancer. We studied the expression of GRN-A in prostate cancer using serum immunoassay and tissue immunohistology procedures for this protein in order to define the clinical value of its measurements.


METHODS
GRN-A production was measured by immunoassay in serum samples from patients with prostate cancer. Immunohistology procedures were used to assess GRN-A expression in paraffin-embedded prostate tissue samples. Serum and tumor findings were evaluated according to the patient's clinical status in studies by us and others.


RESULTS
These studies demonstrated that GRN-A can serve as a prostate cancer serum and tumor marker with clinical value for both diagnosis and prognosis. Serum GRN-A was increased in early- and late-stage disease. Elevated serum GRN-A levels identified some patients with prostate cancer who did not have elevated serum prostate-specific antigen levels. In addition to their diagnostic value, increased serum GRN-A concentrations had prognostic value.


CONCLUSIONS
Our own studies as well as those of others support the clinical potential of GRN-A as a marker for early, progressive, and recurrent prostate cancer. This demonstration of clinical utility notwithstanding, further studies are needed to clearly define the clinical value of GRN-A as a serum and tumor marker for this common cancer.
Deftos
L J
LJ
The Department of Medicine, University of California, San Diego 92161, USA. ljdeftos@ucsd.edu
Abrahamsson
P A
PA
D014408:Biomarkers, Tumor / Q000097:blood*; D053379:Chromogranin A; D002864:Chromogranins / Q000032:analysis / Q000097:blood*; D006801:Humans; D007118:Immunoassay; D008297:Male; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000737:chemistry / Q000175:diagnosis*
D014408:Biomarkers, Tumor; D053379:Chromogranin A; D002864:Chromogranins