carboxypeptidase-b and Prostatic-Neoplasms

Histone acetylation depends on the activity of two enzyme families, histone acetyltransferase (HAT) and deacetylase (HDAC). In this study, we screened various plant extracts to find potent HAT inhibitors. Hot water extracts of allspice inhibited HAT activity, especially p300 and CBP (40% at 100 microg/ml). The mRNA levels of two androgen receptor (AR) regulated genes, PSA and TSC22, decreased with allspice treatment (100 microg/ml). Importantly, in IP western analysis, AR acetylation was dramatically decreased by allspice treatment.Furthermore, chromatin immunoprecipitation indicated that the acetylation of histone H3 in the PSA and B2M promoter regions was also repressed. Finally, allspice treatment reduced the growth of human prostate cancer cells, LNCaP (50% growth inhibition at 200 microg/ml). Taken together, our data indicate that the potent HAT inhibitory activity of allspice reduced AR and histone acetylation and led to decreased transcription of AR target genes, resulting in inhibition of prostate cancer cell growth.

Topics: Acetylation; Androgen Receptor Antagonists; Antineoplastic Agents; Carboxypeptidase B; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Histone Acetyltransferases; Histones; Humans; Male; p300-CBP Transcription Factors; Pimenta; Plant Extracts; Prostatic Neoplasms; Receptors, Androgen; Transcriptional Activation

Treatment of advanced stages of prostate carcinoma with histone-deacetylase inhibitors entails expression of human procarboxypeptidase-A4 (hPCPA4). The three-dimensional structure of hPCPA4 has been solved and shows the features of related metallocarboxypeptidase zymogens, with a preformed alpha/beta/-hydrolase active-enzyme moiety (hCPA4) and an inhibiting pro-domain (PD). The protease moiety recalls a sphere, out of which a spherical cone has been cut. This results in a funnel-like structure, at the bottom of which the active-site cleft resides. The border of this funnel is shaped by loops, which are responsible for the interaction with the PD, characterised by a large interface area and relatively few contacts. Such an inhibitory mode is evocative of the recently reported structure of the human inhibitor latexin in its complex with hCPA4. The main contacting structure of latexin is similar to the one employed for PD inhibition. In both cases, active-site blocking relies mainly on a loop provided by the central part of a beta sheet.

Topics: Amino Acid Sequence; Animals; Antigens; Carboxypeptidase B; Carboxypeptidases A; Crystallography, X-Ray; Enzyme Precursors; Humans; Male; Mice; Molecular Sequence Data; Prostatic Neoplasms; Protein Conformation

Pancreas-specific protein (PASP) was compared with serum amylase in 95 episodes of acute pancreatitis with the diagnoses supported by elevated amylase levels. The etiology was typical for Scandinavian countries, with alcohol as the predominant factor, followed by cholelithiasis. PASP values were clearly raised in all patients, except in three cases found to have high salivary-type amylase levels, and one patient with recurrent alcohol pancreatitis. The rise of PASP levels were in general more pronounced than the corresponding amylase elevations, especially in severe pancreatitis. The elevations were generally parallel for the two analytes, but in 41% of the cases PASP levels remained elevated 2-11 days longer than the corresponding amylase levels. PASP was, however, eliminated from the circulation at a rate comparable to that of amylase. The serum range of PASP for 259 healthy subjects was 15-111 micrograms/L with 95% of the values within 16-98 micrograms/L. The upper reference level was set at 100 micrograms/L. PASP levels were also determined for 291 patients with disorders other than acute pancreatitis. Serum levels in patients with renal insufficiency (n = 12), primary biliary cirrhosis (n = 9), and diabetes mellitus (n = 17) were equal to those in healthy subjects. Eight patients of 173 with acute abdominal disorders and no evidence of pancreatitis had elevated PASP levels as well as 4 patients with prostatic carcinoma (n = 28) and 2 patients with benign prostatic hyperplasia (n = 16). PASP values were low in chronic painful pancreatitis (n = 15) and pancreatic cancer (n = 11).

Topics: Acute Disease; Adult; Age Factors; Aged; Amylases; Biomarkers; Carboxypeptidase B; Carboxypeptidases; Chronic Disease; Diabetes Mellitus; Humans; Male; Middle Aged; Pancreatic Neoplasms; Pancreatitis; Prostatic Hyperplasia; Prostatic Neoplasms; Proteins

Normal Copenhagen rat bone marrow was assayed for growth inhibition of cultured MAT LyLu rat prostate tumor cells. A marrow-derived factor was identified that had significant growth inhibitory activity in vitro against MAT LyLu as well as against DU-145 human prostate tumor and MBT-2 mouse bladder tumor cells but that was noninhibitory to normal rat fibroblasts. The factor was stable to degradation by acid, heat, freezing, trypsin, and carboxypeptidase B. The factor was nonreactive with Coomassie blue, and the molecular weight was estimated as less than 620 daltons. A similar factor was identified in normal human and normal rat sera. The presence of this factor in bone marrow may explain the absence of osseous metastases in the Dunning rat prostate tumor model.

Topics: Animals; Bone Marrow; Carboxypeptidase B; Carboxypeptidases; Cell Division; Cell Line; Humans; Hydrogen-Ion Concentration; Male; Mice; Prostatic Neoplasms; Rats; Temperature; Tissue Extracts; Trypsin; Urinary Bladder Neoplasms