title: Prostate inhibin peptide (PIP) in prostate cancer: a comparative immunohistochemical study with prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP).
abstract: Prostate inhibin peptide (PIP) is a polypeptide synthesized by the prostate gland that is involved in prostatic growth and differentiation. The objective of this study was to evaluate PIP as an immunocytochemical marker for prostatic adenocarcinoma (PCA) by comparing it with PSA and PAP. A total of 71 cases of primary PCA and 5 cases of metastatic PCA were studied. Primary tumors were specially selected to include a disproportionate number of high-grade tumors. The distribution of cases by Gleason score was 2-5, 14 cases; 6-7, 24 cases; and 8-10, 33 cases. Four metastases were to bone (decalcified tissue) and one to soft tissue. All 71 cases of primary PCA stained positively for the three antibodies tested, with none demonstrating obvious superiority, although individual case variability was seen. In one bone metastasis, staining for PSA was negative, with both PAP and PIP giving positive results. All non-prostatic carcinomas tested were negative. These results indicate that PIP is as sensitive and specific an immunohistochemical marker as PSA and PAP in untreated prostate adenocarcinomas. Further, the androgen-independent nature of PIP may give it an advantage over PSA/PAP in tumors exposed to androgen ablating agents.
authors.affiliation: Institute for Research in Reproduction (ICMR), Bombay, India.
authors.forename: S V
authors.initials: SV
authors.lastname: Garde
authors.forename: A R
authors.initials: AR
authors.lastname: Sheth
authors.forename: V M
authors.initials: VM
authors.lastname: Venkatesan
authors.forename: C J
authors.initials: CJ
authors.lastname: Panchal
authors.forename: A T
authors.initials: AT
authors.lastname: Porter
authors.forename: D J
authors.initials: DJ
authors.lastname: Grignon
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism*; D014408:Biomarkers, Tumor; D002277:Carcinoma / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D007265:Inhibins; D008297:Male; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000378:metabolism; D010455:Peptides / Q000378:metabolism*; D017430:Prostate-Specific Antigen / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism*; D029584:Prostatic Secretory Proteins
chemical_list: D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins; D010455:Peptides; D029584:Prostatic Secretory Proteins; C043076:beta-microseminoprotein; D007265:Inhibins; D000135:Acid Phosphatase; D017430:Prostate-Specific Antigen