Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0282612 (PIN)
 2,291 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Surrogate endpoint biomarkers (SEBs) are needed in clinical chemoprevention trials to avoid the excessively long study periods and high costs associated with the use of cancer incidence reduction as an endpoint, particularly with relatively slow-growing tumors such as prostatic adenocarcinoma. SEBs should be directly associated with the evolution of neoplasia, and develop with high frequency in abnormal cells of susceptible individuals. If SEBs can be modified by a particular intervention regimen in short-term studies, the rationale for carrying out long-term studies may be strengthened. The consensus panel identified a small and manageable group of biomarkers measured in tissue or serum as the most promising in prostate cancer chemoprevention, including (1) prostate specific antigen (PSA); (2) morphometric markers, such as nuclear size and roundness; (3) proliferation markers, such as MIB-1 and PCNA; (4) nuclear DNA content (ploidy); (5) oncogene c-erbB-2 (HER-2/neu) expression; (6) angiogenesis; and (7) high-grade prostatic intraepithelial neoplasia (PIN). Information regarding many of these and other biomarkers is limited, calling for further investigation. Also, these factors, chosen chiefly for their proven or proposed utility as prognostic factors, may be less useful as SEBs. It was agreed that concurrent study of numerous markers rather than single markers allows comparison of their relative utility, including assessment of ease of quantitation and the sensitivity, specificity, and positive and negative predictive value.
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PMID:The most promising surrogate endpoint biomarkers for screening candidate chemopreventive compounds for prostatic adenocarcinoma in short-term phase II clinical trials. 752 57

This paper evaluates the use of quantitative methods to accurately assess cell proliferation and death in untreated and treated prostate lesions. The analysis of proliferating cell nuclear antigen (PCNA)-stained nuclei allow precise evaluation of the proliferating cells and exact identification of their location in the progression of untreated prostatic intraepithelial neoplasia (PIN) to prostatic adenocarcinoma (PAC). The evaluation of the frequency and location of apoptotic bodies (ABs) gives accurate information on the apoptotic phenomenon in PIN compared to normal prostate (NP) and PAC. In fact, the frequency of ABs increases from NP to PIN to PAC and parallels that observed with PCNA. However, the AB-related values were approximately one-eighth to one-tenth of those obtained with PCNA immunostaining. Combination endocrine therapy (CET) decreases the proliferative activity and enhances the apoptosis phenomenon in NP, PIN, and PAC. This might indicate that CET could induce a certain degree of regression not only of PAC, but also of PIN.
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PMID:Quantitative characterization of the frequency and location of cell proliferation and death in prostate pathology. 782 97

To investigate possible cell kinetic relations between benign prostatic hyperplasia (BPH), atypical adenomatous hyperplasia (AAH), prostatic intraepithelial neoplasia (PIN) and carcinoma, cell kinetic analyses were performed using radiolabelled DNA-precursors (3H-thymidine autoradiography), immunohistochemistry (proliferation marker Ki67/MIB1 and/or PCNA) and silver staining of nucleolar organizer regions (AgNOR). All methods yielded the lowest values for BPH and AAH, while maximal values were found in carcinoma of high malignancy. PIN was equal to GII-carcinomas, while AAH was between BPH and carcinoma of low malignancy. This investigation ranks BPH, AAH, low grade carcinoma, PIN and high grade carcinoma in order using different methods of cell kinetic analysis. The preneoplastic character of PIN is apparent whereas the character of AAH remains uncertain.
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PMID:Cell kinetic studies on prostatic intraepithelial neoplasia (PIN) and atypical adenomatous hyperplasia (AAH) of the prostate. 860 72

The progression of prostatic intraepithelial neoplasia (PIN) to invasive prostate carcinoma has been analyzed in the C3(1)/T(AG) transgenic mouse model and appears very similar to the process proposed to occur in humans. PIN lesions in these transgenic mice histologically resemble those found in human PIN. Low-grade PIN was observed in the ventral and dorsolateral lobes at 2 months of age, whereas high-grade PIN was found in both lobes by 5 months of age. A progressive increase in the number of PIN lesions was observed with age. Prostate carcinomas, which appeared to arise from PIN lesions, were found by 7 months of age in the ventral lobe and 11 months of age in the dorsolateral lobe. Expression of T(AG) mRNA and protein in these lesions correlated with the development of PIN and carcinomas, as did the overexpression of p53 protein. Apoptosis levels were quite low in normal epithelial cells, moderate in low-grade PIN, and high in high-grade PIN and carcinomas. Levels of expression of proliferating cell nuclear antigen correlated with the degree of severity of the prostate lesions. Eighteen % of PIN lesions were found to already harbor Ha-ras mutations, whereas 33% of carcinomas showed various mutations in Ha-ras, Ki-ras, and/or p53. Mutations in Ha-ras may, therefore, be an early event in a significant portion of PIN lesions. Because high-grade PIN showed many characteristics similar to those observed in carcinomas and high-grade PIN was often found contiguous to carcinomas, we conclude that high-grade PIN is a precursor lesion of prostate carcinoma in this transgenic model. These transgenic mice will be useful to study mechanisms responsible for the progression of invasive carcinomas from PIN precursor lesions, as may occur during the development of prostate cancer in humans.
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PMID:Progression of prostatic intraepithelial neoplasia to invasive carcinoma in C3(1)/SV40 large T antigen transgenic mice: histopathological and molecular biological alterations. 889 41

The most efficient strategy for chemoprevention clinical trials are short-term studies which focus on surrogate endpoint biomarkers (SEBs) in high-risk target populations. High-grade prostatic intraepithelial neoplasia (PIN) is the most likely precursor of prostate cancer, and is found in a significant number of routine contemporary needle biopsies without cancer. The frequency and extent of PIN are decreased with androgen deprivation therapy, suggesting that it is a suitable endpoint biomarker for modulation. Potential SEBs for screening chemopreventive agents for prostate cancer in short-term Phase II trials include (1) histologic premalignant lesions, such as high-grade PIN; (2) biochemical markers, including prostate-specific antigen (PSA) serum concentration; and (3) morphometric markers, including nuclear texture, shape, and roundness; size and number of nucleoli; and number of apoptotic bodies; (4) proliferation markers, including MIB-1 and PCNA; (5) genetic markers, including nuclear DNA content (ploidy), oncogene c-erbB-2 (HER-2/neu) expression, fluorescence in situ hybridization for chromosome 8; and PSA-producing cells in the blood detected by reverse transcriptase polymerase chain reaction; and (6) differentiation markers, such as microvessel density as a determinant of angiogenesis. Each of these endpoint biomarkers is measured easily and accurately in serum or in tissue specimens such as formalin-fixed, paraffin-embedded needle biopsies, and may be modifiable by intervention. The clinical utility of these biomarkers as modulatable endpoints in prostate cancer chemoprevention needs to be demonstrated in future clinical trials.
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PMID:Prostatic intraepithelial neoplasia (PIN) and other prostatic lesions as risk factors and surrogate endpoints for cancer chemoprevention trials. 902 13

With the purpose of establishing morphogenetic features of precancer and early cancer of the prostate gland a comparative immunomorphological evaluation was done of the prostate tumor markers (PAP, PSA, PCNA, and 34 beta E12). Due emphasis is given to the part the basal cell dysplasia plays in morphogenesis of prostatic cancer. The precancer lesions of the prostate include atypical adenomatous hyperplasia, grade I and II prostatic intraepithelial neoplasia (PIN). Grade III prostatic intraepithelial neoplasm is cancer in situ, or uninfiltrative (unpalpable) cancer of the prostate. PIN patients are at high risk for subsequent development of invasive prostatic carcinoma.
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PMID:[The morphogenesis of cancer of the prostate (immunohistochemical research)]. 969 75

Prostate cancer is a disease associated with androgens. It has been hypothesized that reducing the conversion of testosterone (T) to dihydrotestosterone (DHT) in the prostate by the use of the drug finasteride, a 5alpha-reductase inhibitor, will reduce the incidence of prostate cancer. We investigated the chemopreventive potential of finasteride by evaluating its effect on the prostate gland of men with elevated serum prostate-specific antigen (PSA). Fifty-two men with elevated PSA and prostate sextant biopsies negative for cancer were randomized to receive finasteride 5 mg day(-1) (27 patients) or no medication (25 patients) for 12 months and were rebiopsied at 12 months. The biopsies were evaluated for the presence of cancer, the proportion of glandular and hyperplastic tissue, and the presence of high-grade prostatic intraepithelial neoplasia (PIN). Epithelial proliferation was assessed in the prestudy and 12-month biopsies by immunohistochemistry using antibody to proliferating cell nuclear antigen (PCNA). Serum blood samples were drawn at baseline and after 1, 3, 6 and 12 months of study. In the control group, serum levels of PSA and T were unchanged throughout the 12 months. In the finasteride group, PSA decreased 48% (P < 0.001), DHT decreased 67% (P < 0.001) and T increased 21% (P < 0.001). Histological evaluation of prestudy and 12-month biopsy specimens revealed that the finasteride group had a 30% reduction in the percentage of hyperplastic epithelial tissue (P = 0.002), although this decrease was not statistically significantly different between the finasteride and control groups (P = 0.11). In patients with PIN on prestudy biopsy, no change occurred in the PIN lesions with finasteride treatment. Finasteride also had no effect on the proliferation index of prostatic epithelial cells. Of the 27 patients treated with finasteride, eight (30%) had adenocarcinoma of the prostate detected on the 12-month biopsy, compared with one (4%) of the control patients (P = 0.025). In the treatment group, six cancers occurred in the eight patients with PIN on the prestudy biopsy; in the observation group no cancers were detected in the five patients with PIN on the prestudy biopsy (P = 0.021). Two cancers occurred in the 19 men in the treatment group with no evidence of PIN on the prestudy biopsy, compared with one cancer in the 20 men in the observation group with no evidence of PIN on the prestudy biopsy (P = 0.60). This study, using a novel model for evaluating short-term efficacy of chemopreventive or therapeutic agents in men at high risk of prostate cancer, provides little evidence that finasteride is an effective chemopreventive agent for prostate cancer in men with elevated PSA.
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PMID:The effect of finasteride on the prostate gland in men with elevated serum prostate-specific antigen levels. 1048 32

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

With the purpose of studying into the morphogenesis and proliferous activity of the prostatic epithelium under a long-term exposure to low doses of ionizing radiation there have been conducted comparative histological and immunohistochemical (expression of p53 and proliferous cellular nuclear antigen-PCNA) investigations designed to study benign prostatic hyperplasia in patients living in those Ukraine territories affected by radionuclide contamination (group III), residents of Kiev (group II), and patients having been operated on before the Chernobyl accident, having constituted the control group I. It has been found out that the incidence of prostatic intraepithelial neoplasia (PIN), the level of nuclear expression of proteins p53 (in the PIN epithelium) and PCNA (in the epithelium of both benign prostatic hyperplasia and PIN) of patients in groups II and III are by far higher as compared with those in group I. The stroma of benign prostatic hyperplasia in patients of groups II and III was clearly different from that in the control group in that the former was characterized by apparent phenomena of hyalinosis, sclerosis, fibrosis, and extensive inflammatory infiltration, which changes can be explained by a long-term systematic exposure of prostatic tissue to low doses of ionizing radiation.
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PMID:[The immunohistochemical determination of p53 and of proliferating cell nuclear antigen in the epithelial nuclei of benign prostatic hyperplasia following the accident at the Chernobyl Atomic Electric Power Station]. 1067 81

Prostate cancer chemoprevention is an alternative and potential strategy to control this malignancy. Herein, we evaluated the chemopreventive efficacy of grape seed extract (GSE) against prostate cancer in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice where animals were fed with GSE by oral gavage at 200 mg/kg body weight dose during 4 to 28 weeks of age. Our results showed a significant reduction (46%, P < 0.01) in the weight of genitourinary tract organs in the GSE-fed mice. The GSE-fed group of mice had a higher incidence of prostatic intraepithelial neoplasia but showed strong reduction in the incidence of adenocarcinoma compared with mice in control group. Prostate tissue from the GSE group showed approximately 50% (P < 0.001) decrease in proliferating cell nuclear antigen (PCNA)-positive cells and 64% (P < 0.01) reduction in total PCNA protein level compared with the control group; however, GSE increased apoptotic cells by 8-fold. Furthermore, GSE strongly decreased the protein levels of cyclin B1, cyclin A, and cyclin E by 84% (P < 0.05), 96% (P < 0.05), and 89% (P < 0.001), respectively. The protein expression of cyclin-dependent kinases 2 and 6 and Cdc2 was also decreased by more than 90% (P < 0.05) in the prostate from the GSE-fed group. Together, for the first time, we identified that oral GSE inhibits prostate cancer growth and progression in TRAMP mice, which could be mediated via a strong suppression of cell cycle progression and cell proliferation and an increase in apoptosis.
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PMID:Oral grape seed extract inhibits prostate tumor growth and progression in TRAMP mice. 1757 68


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