Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0376358 (prostate cancer)
 59,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hormonal manipulation of prostate cancer is an effective therapy for metastatic disease. Unfortunately, following an initial response tumors reestablish themselves as hormone independent variants and progress. This study was designed to assess the interrelationship of cytokeratin P (Cyto P), vimentin, epidermal growth factor receptor (rEGF) and tissue testosterone following androgen deprivation therapy. Animals bearing the hormone dependent Dunning R3327 G subline prostatic adenocarcinoma were surgically castrated and progressing tumors from both hormone intact and castrated groups were quantitatively assayed for immunohistologic reactivity against the described markers. The results demonstrate a significant (p < 0.05) decrease in cytokeratin (Cyto P), rEGF and testosterone levels following castration. When the expression of both rEGF and Cyto P are related to the tissue testosterone content, it is observed that the ratio between rEGF and testosterone remains essentially unchanged (0.65 +/- 0.21 to 0.65 +/- 0.41), suggesting that in the Dunning R3327 G subline, rEGF expression is coordinately under androgen control. At least some cytokeratin expression also appears to be particularly sensitive to androgen levels, since the ratio between Cyto P and testosterone decreased from 0.92 +/- 0.39 to 0.35 +/- 0.41 following castration. In contrast, following castration, the expression of vimentin was unaffected.
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PMID:Coordinate loss of growth regulatory factors following castration of rats carrying the Dunning R3327 G prostatic tumor. 128 86

Unknown primary malignancy (UPM) is not a disease entity. Rather, it represents a variety of different metastatic, malignant neoplasms all presenting with either an occult primary or having such a highly undifferentiated histologic appearance that an accurate pathologic classification on routine hematoxylin-eosin section is not possible. UPM is a spectrum of malignancies that includes those that are treatable and curable and those for which no specific treatment exists. For the physician, a diagnosis of UPM represents a beginning rather than an end. The minimal workup of such patients includes a thorough history and physical examination, complete blood counts, urine analysis, multichannel chemistries, a chest radiograph, and computed tomography of the abdomen and pelvis. Having completed this workup, further tests are unnecessary and unwarranted unless specific symptoms or physical signs exist. Once the aforementioned workup is completed, the physician must communicate frequently and freely with the pathologist as further diagnostic tests will be laboratory based and include electron microscopy, histochemical stains, and immunocytochemistries. Immunocytochemistries are relatively new laboratory procedures which have made a significant contribution in the accurate pathologic diagnosis of a tissue specimen that in years past would have been classified as an unidentified malignant neoplasm. An initial panel of immunocytochemistries (vimentin, cytokeratin, CEA, and common leukocyte antigen) should be performed on the tissue block in patients with UPM as they provide direction in the accurate classification of the malignant neoplasm. Chromosomal analysis of tissue is useful in the recognition of lymphomas or soft-tissue sarcomas which would otherwise be classified as UPM. In years to come, when specific DNA probes capable of identifying specific chromosomal rearrangeaments are widely available, pathologic classification of UPM will be performed on a molecular level. Some unknown primary malignancies are treatable and potentially curable. These include large cell lymphoma, extragonadal germ cell malignancies, squamous cell carcinoma metastatic to cervical lymph nodes without an obvious primary, metastatic adenocarcinoma to axillary lymph nodes in women (invariably on occult breast primary), and malignant ascites in women, which usually represents ovarian cancer. Metastatic adenocarcinoma of unknown primary origin, with the exception noted above and the rare presentation of an occult prostate cancer as UPM, is an ultimately fatal malignancy with a relatively shor clinical course.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Malignancies of undetermined primary origin. 154 98

To evaluate if there is any consistent relationship between the expression of intermediate filament proteins (IFP), particularly keratins, and the degree of malignancy of prostatic cancer cells, a series of nine Dunning rat prostatic cancer sublines that span the entire spectrum of progression of prostatic cancer were studied immunocytochemically by the use of a variety of antibodies specific for keratins, vimentin, or desmin. For the keratin studies, monoclonal antibodies with either a general reactivity to several keratins or highly specific for either luminal or basal epithelial cells of the normal rat prostate were used. By use of an antibody specific for luminal cell keratin 18, the luminal tumor cells of the well-differentiated, slow-growing H and HI-S sublines were positively stained. In most of the sublines with a more advanced state of progression (i.e., the moderately differentiated, moderately fast growing HI-M; the poorly differentiated, faster growing HI-F; and the anaplastic, very fast growing AT-1, AT-2, and MAT-Lu tumors), however, no expression of keratin specific for luminal cells was detected. In addition, several of the most advanced sublines (i.e., AT-1, AT-2, and MAT-Lu) were negative using any of the keratin antibodies. In contrast, several of the other sublines with the most advanced degree of progression (i.e., the anaplastic, very fast growing MAT-LyLu tumor derived from the AT-1 subline; and the anaplastic, very fast growing AT-3 tumor, derived from the HI-F subline), however, were positively stained with the keratin antibody specific for the luminal cells. By use of the keratin antibody specific for the basal cells of the normal rat prostate, the basal tumor cells of the well-differentiated slow-growing H and HI-S tumor were positively stained. This positive staining for basal cell keratin was also found in the HI-M and HI-F tumors, while the AT-1, AT-2, MAT-Lu, MAT-LyLu, and AT-3 were negative with this antibody. Thus, a loss in staining for basal cell keratin was consistently associated with the most advanced state of tumor progression. Vimentin-positive staining was demonstrated either alone or with keratin-positive staining in part of the epithelial cancer cells of all the sublines. An increase in the positive staining for vimentin was consistently associated with a more advanced state of tumor progression. Desmin-positive staining was found only in smooth cells present within the various tumor sublines.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Intermediate filament expression and the progression of prostatic cancer as studied in the Dunning R-3327 rat prostatic carcinoma system. 266 36

In search of biomarkers that predict of human prostate cancer progression, we hypothesized that these markers must be expressed in prostatic epithelial cells during multi-step prostate carcinogenesis. Since both genetic and epigenetic factors have been implicated in human prostate cancer development, two osseous-metastatic experimental models were developed in our laboratory, one based on gene transfection and the other on stromal-epithelial interaction studies. In the genetic model, PC-3 cells transfected with point-mutated c-erbB-2/neu oncogene subsequently acquired the potential to metastasize from the prostate to soft tissues and the skeleton. In the epigenetic model, sublines derived from the parental androgen-dependent LNCaP cell line metastasized from the primary tumor to the lymph node and bone. Cells with known lineage relationships were cloned from both the primary and the metastatic tumors and were characterized extensively using cellular, biochemical, immunohistochemical, and molecular techniques. Relevant stage-specific biomarkers associated with prostate cancer progression in these two models were defined and used to evaluate human prostate tissues obtained from the clinic. In this communication, we focused our discussion on the potential importance of c-erbB-2/neu oncogene, vimentin, hepatocyte growth factor/scatter factor and its receptor, c-met oncogene, tumor angiogenesis and neuroendocrine factors as biomarkers for human prostate cancer progression.
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PMID:Biomarkers associated with prostate cancer progression. 752 53

Human prostatic cancer cells JCA-1 were induced with a phorbol ester 12-o-tetradecanoylphorbol-13-acetate (TPA), and cell growth differentiation were analyzed. Within hours of exposure to TPA, cell proliferation decreased and reached approximately 80% reduction after 3 days, as determined by [3H]thymidine incorporation and cell counting. Cell cycle analysis revealed a blocking of cells entering into the replicating S and G2M phases from the G1 phase. The TPA induced cells had a reduced growth rate but remained viable. The growth-modulating activity of TPA was similarly observed with LNCaP cells. Agarose gel electrophoresis of the chromosomal DNA from induced cells exhibited a non-fragmented pattern excluding the possibility of cell apoptosis. In parallel to the growth reduction, the TPA induced cells became larger in size showing dendrite like cytoplasmic extensions. Furthermore, JCA-1 cells treated with TPA acquired the expression of cytokeratin 18 and increased the expression of actin and vimentin by 300%. These results indicate an induced growth reduction accompanied by cellular differentiation of the prostatic cancer cells.
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PMID:Growth attenuation in a human prostate cell line mediated by a phorbol ester. 777 Apr 65

Prostate cancer with marked neuroendocrine (NE) differentiation belongs to the hormone resistant carcinomas. We report the development of TSH-secreting small cell prostate cancer (SCPC) from high grade adenocarcinoma (Gleason score 8) with an elevated number of chromogranin A positive cells located in benign structures adjacent to the cancer. Conversion to SCPC was followed-up during 4 years. The initial adenocarcinoma exerted a stronger positivity for PAP than for PSA (respective staining indexes, Sls, 2.2 and 1.8, maximum staining 3.0). In the developed SCPC, 2 cell subpopulations that were derived from epithelial cells were found (positive stain for EMA and CEA, respectively) and from one of them originated CEA-positive liver metastases. Blood CEA and NSE levels were elevated in SCPC (284 ng/ml and 24.5 ng/ml). However, blood TPS level which reflects proliferation of epithelial cells was within the normal range. The development of a << pure >> sarcomatoid prostatic tumor from adenocarcinoma with 2 areas of similar differentiation grades (Gleason score 7 and 9-10) that initially differ in staining for PSA and PAP (SIs for PSA were 1.2 and 0.02 and for PAP were 1.6 and 0.02, respectively) was followed-up during 4 years of treatment with Estracyt. Adenocarcinoma tissue specimens was slightly CEA-positive. The disappearance of lower grade adenocarcinoma during treatment was accompanied by the development of sarcomatoid areas that were 100% vimentin positive. In the last year of follow-up the primary tumor was composed only of vimentin positive sarcomatoid cells with a slight positivity for Chromogranin A, NSE and ACTH. In parallel, normal serum PSA and PAP values and elevated CEA and NSE serotests (12.6 ng/ml and 24.7 ng/ml, respectively) were found. Blood TPS level was at the upper limit of the normal range. Scintigraphy revealed extensive liver metastases. The recorded data indicate (i) extremely poor prognoses associated with high grade adenocarcinomas that demonstrate stronger immunohistochemical positivity for PAP than that for PSA (ii), chromogranin A positive cells in benign structures adjacent to the cancer as a possible paracrine promoter of SCPC from poorly differentiated adenocarcinoma, and (iii) a high degree of heterogeneity of both SCPC and sarcomatoid prostatic neoplasms with some evidence for definite links (EMA and CEA) to secretory epithelial cells.
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PMID:Immunohistochemical staining and serotest markers during development of a sarcomatoid and small cell prostate tumor. 784 May 15

c-erb B2/neu has been demonstrated to be a transforming oncogene in both rodent and human prostatic epithelial cells. To understand the potential role of neu in human prostatic cancer progression, we used a transfer procedure to determine whether neu amplification/overexpression leads to increased tumor growth and metastasis. We chose an androgen-independent human prostatic epithelial cell line, PC-3, as the target for gene transfer. PC-3 cells were cotransfected with pSVneu-T (a point-mutated rat neu oncogene construct) and pSV2neo, and single-cell cloned. Fifty cell clones were isolated and characterized, of which two neu-transfected clones (N17 and N35) and a neo control clone (C32) were studied extensively with respect to neu gene integration, levels of neu mRNA and protein expression, anchorage-independent growth, and tumorigenic and metastatic potential. Results showed that: 1) Clone N35 contained 70 copies of the neu oncogene and a high level of neu mRNA transcripts. It acquired increased anchorage-independent growth potential in vitro and increased tumorigenicity in vivo. 2) Clone N17 contained 10 copies of the neu oncogene and a low level of neu mRNA transcripts. It did not acquire additional capability for anchorage-independent growth and tumorigenic potential as compared to the controls. 3) Despite an increased level of neu mRNA transcripts present in clone N35, there was no corresponding increase of the steady-state levels of neu protein in this particular clone. 4) When administered subcutaneously, none of the cell clones tested, including the control neomycin-resistant clone, acquired metastatic potential. However, clone N35 exhibited marked metastatic potential when administered orthotopically; this cell clone was found to disseminate widely to the lymph nodes, kidney, skeletal muscle, lung, liver, and bone. 5) When neu-transfected cell subclones from N35-induced primary and metastatic lymph node, kidney, and bone tumors were analyzed for cytoskeletal, extracellular matrix, and cell adhesion protein expression, the bone metastatic subclone exhibited increased levels of vimentin and collagen IV and decreased levels of cytokeratin and ICAM-1. These results, taken together, suggest that neu transfection induces secondary changes, which, rather than neu protein per se, are responsible for the acquisition of tumorigenic and metastatic potential of prostate cancer cells when an appropriate host microenvironment is present.
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PMID:Transfected neu oncogene induces human prostate cancer metastasis. 860 95

We have developed a simple and effective method, designated linker capture subtraction (LCS), for cloning differentially expressed genes between two cell types or between cells treated in two different ways. In the first step of the method, two mRNA populations are converted to double-stranded cDNAs, fragmented, and ligated to linkers for PCR amplification. In the second step, the linkered DNA (tester) from one mRNA population is hybridized to an excess of the unlinkered DNA (driver) from the other mRNA population, followed by incubation with mung bean nuclease which digests single-stranded DNA specifically. This leaves only tester-tester homohybrids to be amplified by PCR in the following step, so as to achieve an enrichment of tester-specific sequences. The amplified PCR products are then used as tester for another round of subtraction. The process of subtraction is carried out three times, and the final PCR products are inserted into a vector for clonal analysis. We have used the strategy to begin to clone and identify the genes expressed differentially between the human prostate cancer cell lines LNCaP and PC-3, which have different tumorigenic and metastatic potentials. We demonstrated strong enrichment of target sequences. We also report the identities of two of the genes expressed differentially in these cell lines. One is prostate-specific antigen (PSA) which is known to be expressed in LNCaP but not in PC-3. The other is vimentin, the differential expression of which has not been reported previously in these prostate cancer cells.
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PMID:Cloning differentially expressed genes by linker capture subtraction. 866 May 44

Chemoprevention is the administration of agents to prevent induction and inhibit or delay progression of cancers. For prostate, as for other cancer targets, successful chemopreventive strategies require well-characterized agents, suitable cohorts, and reliable intermediate biomarkers of cancer for evaluating chemopreventive efficacy. Agent requirements are experimental or epidemiological data showing chemopreventive efficacy, safety on chronic administration, and a mechanistic rationale for the observed chemopreventive activity. On this basis, promising chemopreventive drugs in prostate include retinoids, antiandrogens, antiestrogens, steroid aromatase inhibitors, 5alpha-reductase inhibitors, vitamins D and E, selenium, lycopene, and 2-difluoromethylornithine. Phase II trials are critical for evaluating chemopreventive efficacy. Cohorts in these trials should be suitable for measuring the chemopreventive activity of the agent and the intermediate biomarkers chosen as endpoints. Many cohorts proposed for phase II trials are patients with previous cancers or premalignant lesions. For such patients, trials should be conducted within the context of standard treatment. Two cohorts currently used in phase II prostate cancer chemoprevention trials are patients with PIN and patients scheduled for prostate cancer surgery. Biomarkers should fit expected biological mechanisms, be assayed reliably and quantitatively, measured easily, and correlate to decreased cancer incidence. Protocols for adequately sampling tissue are essential. Changes in PIN provide prostate biomarkers with the ability to be quantified and a high correlation to cancer. PIN measurements include nuclear polymorphism, nucleolar size and number of nucleoli/nuclei, and DNA ploidy. Other potentially useful biomarkers are associated with cellular proliferation kinetics (e.g. PCNA and apoptosis), differentiation (e.g. blood group antigens, vimentin), genetic damage (e.g. LOH on chromosome 8), signal transduction (e.g. TGFalpha, TGFbeta, IGF-I, c-erbB-2 expression), angiogenesis, and biochemical changes (e.g. PSA levels).
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PMID:Chemoprevention of prostate cancer: concepts and strategies. 1032 87

Ionizing radiation (IR) is an important component in the therapy of localized prostate cancer. Identification of protein alterations during IR-induced apoptosis prostate cancer cells is an important step toward understanding the new metabolic status of the dying cell. In the present study, we report changes in protein profile that define the execution phase of the apoptotic response in the in vitro model of tumorigenic radiation-transformed SV40-immortalized human prostate epithelial cells (267B1-XR), induced to undergo programmed cell death by IR. We employed an approach that involves use of analytical two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) coupled with Western blotting with specific antisera. Our results point out that apoptotic cells experience significant reduction in the levels of the intermediate filament proteins, keratins-18, 19, vimentin and the associated 14-3-3 adapter proteins. At the same time, molecular chaperones such as glucose-regulated protein 94, calreticulin, calnexin, and protein disulfide isomerase exhibit marked accumulation in these dying cells. The present data indicate that apoptosis-associated processes in prostate epithelial cells include solubilization of the rigid intermediate filament network by specific proteolysis as well as increased levels of endoplasmic reticulum (ER) proteins with chaperone functions.
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PMID:Protein changes associated with ionizing radiation-induced apoptosis in human prostate epithelial tumor cells. 1034 86


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