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Query: UMLS:C0376358 (
prostate cancer
)
59,338
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We retrospectively evaluated 51
prostate cancer
patients found to have pelvic lymph node metastases at the time of pelvic lymphadenectomy and 125I implantation. All of them were followed until death or for a minimum of 70 months. Rabbit polyclonal anti-PSA, anti-PAP, anti-
PSP-94
, and mouse TURP-27 monoclonal antibodies were used in immunohistochemical evaluation of the metastatic lesions. In addition, Gleason grade and ploidy were assessed and correlated. No tumor with a Gleason grade of less than 7 could be found in the metastatic lymph nodes. Time to progression (P = .003), disease-specific survival (P = .009), and overall survival (P = .003) were significantly shorter in patients whose tumors had a primary Gleason pattern of 5 (grade 9 or 10). In the PSA study, patients whose tumors were reactive in more than 75% of cancer cells experienced significantly longer survival than those with less than 75% of cancer cells expressing PSA (P = .0006 log rank test). The means of overall survival +/- SEM were 71.5 +/- 5.0 and 34.9 +/- 5.4 months, respectively. Similar correlations were found with disease-specific survival and time to progression. Patterns of PAP expression and TURP-27 reactivity were not prognostically useful, whereas
PSP-94
expression may add some additional information. These data suggest that evaluation of tissue PSA heterogeneity in lymph node metastases may offer additional prognostic information on
prostate cancer
patients. Better prediction of individual prognosis may be possible with the combined use of Gleason grade, flow cytometry, and PSA expression.
...
PMID:Prognostic significance of antigenic heterogeneity, Gleason grade, and ploidy of lymph node metastases in patients with prostate cancer. 137 12
cDNA libraries were generated from the prostate gland tissue obtained from a normal donor and from a patient with
prostate cancer
. Subtractive cDNA cloning was used to identify phenotype-specific cDNA sequences from both normal and cancerous prostate tissue. One clone, pN44, isolated from normal prostate tissue, codes for the prostate protein
PSP94
, expression of which appeared to be down-regulated in the cancerous cells. Rabbit antisera against
PSP94
were generated, and these antisera can be used to detect
PSP94
in urine. Two other clones, pN23a and pN141f, were also found to be down-regulated.
...
PMID:Decreased expression of prostatic secretory protein PSP94 in prostate cancer. 750 90
While performing reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of total mRNA from
prostate cancer
specimens, two forms of
PSP94
cDNA were detected. RT-PCR products were analysed by Southern blotting and probing with exon-specific oligonucleotides. In the short form of
PSP94
mRNA, designated as
PSP57
, exon III was found to be deleted. The two mRNA forms were confirmed by cloning and sequencing of the RT-PCR products and were found to result from alternative splicing. The alternatively spliced form,
PSP57
, was characterized by sequence analysis.
PSP94
and
PSP57
possess identical exons I and II, including identical secretion signal peptide and the 5' untranslated sequences.
PSP57
has a frame-shifted exon IV and encodes a putative 57 amino acid protein with a novel, highly basic C-terminus of 41 amino acids.
PSP57
mRNA was detected in other urogenital tissues (kidney, bladder) and in most tumor cell lines tested, but was not detectable in other tissues such as breast and lung. In prostate tumor cell lines,
PSP57
mRNA was aberrantly spliced and localized in the nuclear fraction of the cell. Our results suggest the possible existence of a novel PSP protein that originates from alternative splicing of
PSP94
mRNA in urogenital tissues.
...
PMID:Alternative splicing of PSP94 (prostatic secretory protein of 94 amino acids) mRNA in prostate tissue. 756 62
PSP94
has the potential to be a useful diagnostic marker and therapeutic agent in
prostate cancer
. Recently, different immunoassay systems for quantitative analysis of
PSP94
in clinical samples have been developed, but the epitope structure of
PSP94
protein has not been elucidated. In this study, we report an Escherichia coli expression system for recombinant GST-
PSP94
fusion protein. GST-
PSP94
contains antigenic determinants similar to natural
PSP94
protein (determined both by Western blotting experiments and by ELISA) and can be used to study the structure of natural
PSP94
antigen. Since GST-
PSP94
was expressed in E. coli and purification involved a denaturing process, we propose that the epitope structure of
PSP94
is linear and largely dependent on the primary amino acid sequence, rather than conformational structure. This hypothesis was supported by reciprocal competition in ELISA among natural, GST-
PSP94
fusion protein, and purified recombinant
PSP94
protein. The results demonstrate that the various forms of
PSP94
can compete with each other in binding to rabbit
PSP94
polyclonal antibody, although the natural
PSP94
has a slightly higher affinity. When natural and recombinant
PSP94
protein were denatured in vitro with urea and alkali, no effect on the binding to antibody was found. The epitope activity of natural
PSP94
was also shown to be resistant to the treatment of detergent and reducing agent. The location of one of the linear epitopes recognized by the
PSP94
antibody was determined to be in the N-terminus by using two synthetic peptides representing N- and C-terminal sequences. Competitive ELISA between the N-terminal peptide and
PSP94
protein indicate that both natural and GST-
PSP94
have similar immunoactive N-termini.
...
PMID:Recombinant PSP94 (prostate secretory protein of 94 amino acids) demonstrates similar linear epitope structure as natural PSP94 protein. 889 4
PSP94
has shown potential to be a serum biomarker for evaluating
prostate cancer
. Studies of the epitope structure is crucial for this endeavour. In this article, we have used 15 different monoclonal antibodies (MAb) to analyse the epitope structure of
PSP94
and to compare with the results obtained from our previous work using polyclonal antibody and recombinant
PSP94
. Firstly, we determined the relative activities of the 15 MAb population by direct and competitive ELISA. The two predominant MAbs (MAb PSP-6 and -19) in 15 MAbs were selected for further studies of the epitope structure. By comparing the binding activities of recombinant GST-
PSP94
and natural
PSP94
with MAbs, and by comparing their affinity with MAbs in an in vitro denaturing experiment,
PSP94
was shown to have a similar, prevalently linear epitope structure as we demonstrated by polyclonal antibody. Using recombinant GST fusion protein with
PSP94
and with each half of the N- and C-terminal 47 amino acids (GST-PSP-N47/C47) in E. coli cells, the different epitopes recognized by 15 monoclonal antibodies were delineated and the polar distribution of the epitope structure of
PSP94
was characterized. Results of direct ELISA of recombinant N47 and C47 and their competitive binding against natural
PSP94
(competitive ELISA) showed that the N- and C-termini represent the immuno-dominant and immuno-recessive area separately. A majority of the monoclonal antibodies (12/15) showed preferential binding of the N-terminal sequence of the
PSP94
protein. Using GST-PSP-N47 as a standard protein, an epitope map of the 15 monoclonal antibodies was obtained. The results of this study will help to define the clinical utility of
PSP94
.
...
PMID:Analysis of epitope structure of PSP94 (prostate secretory protein of 94 amino acids): (II). Epitope mapping by monoclonal antibodies. 913 77
Prostate secretory protein of 94 amino acids (PSP94) has shown the potential to be a diagnostic biomarker and a therapeutic agent for
prostate cancer
. Primates have been the main animal models for studying the biology of this molecule. We have cloned and analyzed the cDNA and promoter region of PSP94 from baboon (Papio anubis). Sequence divergence among baboon, monkey, pig, and human, in both the exons and 5'-flanking region indicates rapid evolution of the PSP94 gene. There are conserved steroid hormone response elements (SHRE) in the promoter region of all three primate species. Multiple, alternative transcripts starting near these SHREs and upstream to the TATA box were identified by reverse transcriptase polymerase chain reaction (RT-PCR) and rapid amplification of 5'-cDNA ends (5' RACE) in primate prostatic tissues. This differential transcription initiation may be linked to androgen regulation of PSP94 gene expression. PSP94 transcripts were detected by RT-PCR in a wide variety of mucus-secreting tissues. However, the alternative transcripts were found only in the prostate. The distribution of the PSP94 protein in baboon secretory tissues was also examined by Western blot analysis using a polyclonal antibody against the human homolog. A positive immunoreactive band was detected, but it was weak, due probably to epitope divergence between the two species. In all young, healthy primate animals tested, the level of immunoreactive PSP94 in prostate tissues was lower than expected. In addition, RT-PCR combined with Southern blot analysis on prostate tissues in these animals failed to detect the
PSP57
mRNA produced by alternative splicing of PSP94 primary transcript. These observations can be explained by the sexual immaturity and incomplete prostate development in these young primates. This explanation was supported by histological examination of their prostate during PSP94 immunohistochemistry.
...
PMID:Molecular cloning and gene expression analysis of PSP94 (prostate secretory protein of 94 amino acids) in primates. 917 67
Prostate secretory protein (
PSP94
, 94 amino acids) is one of the most abundant proteins secreted from the prostate. Its biological role is unknown and still controversial, although it is assumed to have the potential to be a biomarker and a suppressor of
prostate cancer
. In order to establish an animal model to further elucidate its biological role, we expressed the mature form of rat
PSP94
in Escherichia coli, using a glutathione S-transferase (GST) fusion expression vector; we generated a polyclonal rabbit antibody against the recombinant protein. The antibody specifically recognized recombinant rat
PSP94
and cross-reacted only very weakly with its human homologue. Using the characterized anti-rat
PSP94
antibody, we found that
PSP94
was located primarily in rat prostate. Furthermore,
PSP94
is present at different levels in different lobes of rat prostate, with significant levels detectable only in the lateral lobe (LP). In addition, the most abundant
PSP94
expression was found in the prostate lobe secretions, and
PSP94
levels in LP secretions were at least seven times higher than in secretions from the dorsal prostate (DP). The rat ventral prostate (VP) and other regions of the male accessory glands were found to be almost completely devoid of
PSP94
. Since most rat prostate dysplasia induced by steroid hormone treatment occurs only in dorsolateral prostate, prostate tissue-specific expression and the expression of
PSP94
in dorsolateral, but not other, lobes of the prostate suggest a potential role in prostate targeting and
prostate cancer
development.
...
PMID:Differential expression of PSP94 in rat prostate lobes as demonstrated by an antibody against recombinant GST-PSP94. 1041 42
PSP94
(prostate secretory protein of 94 amino acids) was regarded as a possible
prostate cancer
marker, however, it has been controversial. All prior studies were designed to test the free form in serum using antibodies to
PSP94
. Results presented here demonstrate that
PSP94
exists in
prostate cancer
patients in two forms, free and bound, and that the majority is present as serum bound complexes. This result was demonstrated by using both native and SDS-PAGE analyses of serum proteins from
prostate cancer
patients. Chromatographic separation of serum total proteins by a molecular sieve column generated two peaks (peak I and II), which were reactive with rabbit antiserum to human
PSP94
in Western blot experiments. Peak I was eluted before the IgG fraction at a molecular weight larger than 150 kDa, and peak II appeared after serum albumin ( approximately 67 kDa) was eluted. By using a biotinylated
PSP94
as an indicator of the free form of
PSP94
, we demonstrate that peak I contains serum
PSP94
-bound complexes and peak II is likely the free form of serum
PSP94
. Since the molecular weight of serum
PSP94
-bound complexes is close to IgG during molecular sieve separation, serum
PSP94
complexes were further purified through two rounds of protein A column separation, followed by DEAE-ion exchange column chromatography. In vitro dissociation tests of the purified
PSP94
-bound complexes showed that the binding of serum
PSP94
-complexes is probably via disulfide bonds and is chemically stable. The results presented here indicate that serum
PSP94
-bound complexes must be considered in evaluating the clinical utility of
PSP94
as a
prostate cancer
marker.
...
PMID:Serum bound forms of PSP94 (prostate secretory protein of 94 amino acids) in prostate cancer patients. 1058 Oct 2
To date, the rodent ventral prostate (VP) has been the focus of many studies on androgen action, less attention has been directed to the lateral prostate (LP) and the dorsal prostate (DP). The rodent VP has no clear homologous counterpart in the human prostate. The rodent LP and DP is the only prostate lobe comparable to the peripheral zone of the human prostate, where hormone-induced
prostate cancer
mainly occurs. To explore its utility for prostate targeting, we have studied the gene expression of
PSP94
with rat probasin (rPB), a gene commonly used for prostate targeting in
prostate cancer
research and a gene typically responsive to androgen regulation. Firstly, we demonstrated
PSP94
gene transcription being more specific to the LP and DP lobes than rPB, where rPB RNA was detected in the LP and DP and other lobes at different levels. Secondly, we found that
PSP94
gene transcription decreased relatively slowly in response to androgen deprivation but recovered rapidly in response to testosterone replacement after complete ablation of
PSP94
transcription. In the VP, gene transcripts of rPB were specifically responsive to androgen deprivation; however, they responded relatively slowly in the LP and DP. RNase protection experiments indicated that the slow response was not due to abnormal persistence of
PSP94
messenger RNA specifically in the DP and LP lobes in comparison with rPB. Thirdly, Western blot analysis revealed that both
PSP94
and rPB expression is specific to the LP and DP at the protein level, exhibiting slow responses to testosterone replacement after castration. We conclude that
PSP94
gene expression at the transcriptional level is more specific to the LP and DP than rPB and thus less sensitive to androgen ablation. This may have clinical implications for strategies to target the prostate in cancer therapy.
...
PMID:Rodent PSP94 gene expression is more specific to the dorsolateral prostate and less sensitive to androgen ablation than probasin. 1131 82
To date, only a few prostate-specific vector genes have been tested for prostate targeting in gene therapy of
prostate cancer
(CaP). Current clinical trials of gene therapy of CaP utilize the only two available vector genes with a combination of a rat probasin promoter and a human PSA promoter sequence in an adenovirus vector to target CaP. There is an urgent need to establish additional vector gene systems to sustain and propagate the current research. Since
PSP94
(prostate secretory protein of 94 amino acids) is one of the three most abundant proteins secreted from the human prostate and is generally considered to be prostate tissue-specific in both human and rodents, we performed a transgenic experiment to assess the promoter/enhancer region of
PSP94
gene-directed prostate targeting. Firstly, a series of progressive deletion mutants of a 3.84 kb
PSP94
gene promoter/enhancer region (including parts of the intron 1 sequence) linked with a reporter LacZ gene was constructed and assessed in vitro in cell culture. Next, transgenic mice were generated with two transgene constructs using the SV40 early region (Tag oncogene) as a selection marker.
PSP94
gene promoter/enhancer region-directed SV40 Tag expression specifically in the mouse was demonstrated in three breeding lines (A, B, C, n = 374) by immunohistochemistry staining of Tag expression. Specific targeting to the prostate in the
PSP94
gene-directed transgenic CaP model was characterized histologically by correlation of SV40 Tag-induced tumorigenesis (tumor grading) with puberty and age (10-32 weeks). Prostatic hyperplasia was observed as early as 10 weeks of age, with subsequent emergence of prostatic intraepithelial neoplasia (PIN) and eventually high grade carcinoma in the prostate. The
PSP94
transgenic mouse CaP model was further characterized by its tumor progression and metastatic tendency at 20 weeks of age and also by its responsiveness and refractoriness to androgen manipulation. This study indicates that the
PSP94
gene promoter/enhancer has the potential for prostate specific targeting and may ultimately be of use in gene therapy of CaP.
...
PMID:Prostate targeting: PSP94 gene promoter/enhancer region directed prostate tissue-specific expression in a transgenic mouse prostate cancer model. 1242 11
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