Browsing by Subject "PSA"

Now showing 1 - 3 of 3
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    Novel Prostate-Specific Promoter Derived from PSA and PSMA Enhancers
    (Elsevier, 2002-09) Lee, Sang-Jin; Kim, Hong-Sup; Yu, Rong; Lee, KangRyul; Gardner, Thomas A.; Jung, Chaeyong; Jeng, Meei-Huey; Yeung, Fan; Cheng, Liang; Kao, Chinghai; Pathology and Laboratory Medicine, School of Medicine
    The expression of prostate-specific membrane antigen (PSMA) and prostate-specific antigen (PSA), two well characterized marker proteins, remains highly active in the hormone refractory stage of prostate cancer. In this study, an artificial chimeric enhancer (PSES) composed of two modified regulatory elements controlling the expression of PSA and PSMA genes was tested for its promoter activity and tissue specificity using the reporter system. As a result, this novel PSES promoter remained silent in PSA- and PSMA-negative prostate and non-prostate cancer cell lines, but mediated high levels of luciferase in PSA- and PSMA-expressing prostate cancer cell lines in the presence and absence of androgen. To determine whether PSES could be used for in vivo gene therapy of prostate cancer, a recombinant adenovirus, Ad-PSES-luc, was constructed. Luciferase activity in prostate cancer cell lines mediated by Ad-PSES-luc was 400- to 1000-fold higher than in several other non-prostate cell lines, suggesting the high tissue-specificity of the PSES promoter in an adenoviral vector. Finally, recombinant virus Ad-PSES-luc was injected into mice to evaluate the tissue-discriminatory promoter activity in an experimental animal. Unlike Ad-CMV-luc, the luciferase activity from systemic injection of Ad-PSES-luc was fairly low in all major organs. However, when injected into prostate, Ad-PSES-luc drove high luciferase activity almost exclusively in prostate and not in other tissues. Our results demonstrated the potential use of PSES for the treatment of androgen-independent prostate cancer patients.
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    Paper Spray - Mass Spectrometry: Investigation of Sampling Devices for Illicit Drug Detection and Quantification
    (2021-07) Nguyen, Chau Bao; Manicke, Nicholas E.; Goodpaster, John V.; Deiss, Frederique T.
    Paper spray - mass spectrometry (PS-MS) has been developed as a rapid and direct ionization method for qualitative and quantitative analysis of complex samples at trace levels. In this work, different sampling devices for PS-MS were investigated to improve the assay’s simplicity and sensitivity over traditional approaches. In particular, chapter two characterizes an alternate paper substrate to enhance drug detection on surfaces like asphalt, cloth, concrete, aluminum, and glass. Analysis occurs on a single spray ticket coated with pressure-sensitive adhesive (PSA), also known as Post-it notes to detect and quantify drug residues. A PS-MS method utilizing PSA paper was developed to detect a mixture of ten drugs off of various surfaces to evaluate the qualitative and quantitative capabilities of the aforementioned substrate. After the method development on a conventional linear ion trap mass spectrometer, the assay was translated for use on a portable mass spectrometer to evaluate the suitability of the pressure-sensitive adhesive paper substrate in the field in chapter three. Chapter four introduces a sampling device combined with a snap-in solid-phase extraction (SPE) column. The new cartridge design not only inherits the functions from the first iteration SPE cartridge, including extraction and preconcentration from complex samples, but also exhibits greater flexibility in volume control and ease of use for on-site sample collection.
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    The Relationship Between PSA and Total Testosterone Levels in Men With Prostate Cancer
    (Oxford University Press, 2022) Flores, Jose M.; Bernie, Helen L.; Miranda, Eduardo; Nascimento, Bruno; Schofield, Elizabeth; Benfante, Nicole; Carlsson, Sigrid; Mulhall, John P.; Urology, School of Medicine
    Background: Prostate-specific antigen (PSA) secretion is a testosterone (T) dependent process. Published data suggest that a low T level is an independent predictor of higher-grade prostate cancer (PC). Aim: To evaluate the relationship between T and PSA in patients with PC. Methods: All men diagnosed with PC with a recorded pre-treatment total T level measurement were included in this analysis. We analyzed demographic, clinical, and pathological data. Patients were stratified according to pretreatment PSA levels: <2 ng/mL, 2-4 ng/mL, >4 ng/mL. Low T was defined as total T < 10.4 nmol/L (300 ng/dL), very low T < 6.9 nmol/L (200 ng/dL). Outcomes: T levels by PSA groups according to the PC pathology. Results: In this retrospective study, mean patient age was 61 years among 646 men. The distribution by PSA group was: 8% (<2), 17% (2-4), and 76% (>4). The mean T level across the entire cohort was 13 nmol/L (374 ng/dL). Overall, 30% had a T level < 10.4 nmol/L (300 ng/dL). The mean total T level by PSA group was: <2 ng/mL, 7 nmol/L (206 ng/dL); 2-4 ng/mL, 13 nmol/L (362 ng/dL); >4 ng/mL, 14 nmol/L (393 ng/dL), P < .001. PSA <4 ng/mL was a significant predictor of low T in men with PC GS ≥8. PSA <2 ng/mL was a significant predictor of very low T independent of the PC pathology. Clinical implications: These findings suggest that clinicians should consider measuring T levels when a patient diagnosed with PC GS ≥8 and PSA level <4 ng/mL, and for each patient with PSA level <2 ng/mL independent of the PC pathology. Strengths & limitations: Our study has several strengths including (i) inclusion of a large population of men, (ii) use of a database which is audited and reviewed for accuracy annually, and (iii) use of an accurate T assay (LCMS). Nonetheless, there are limitations: (i) the subjects of the study are from a single institution, and (ii) we did not measure free T levels. Conclusion: In men with PC with GS ≥8, PSA level <4 ng/mL predicts low T. PSA <2 ng/mL predicts very low T independent of the PC pathology.