DIFFERENT FORMS OF PROSTATE-SPECIFIC ANTIGEN IN CANCER

癌症中不同形式的前列腺特异性抗原

• 批准号: 2414269
• 负责人: MARY J HEEB
• 金额: $ 8.8万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-05-01 至 1999-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2414269
• 关键词: SDS polyacrylamide gel electrophoresis; alpha 1 antitrypsin; antibody specificity; biomarker; chemical synthesis; chymotrypsin; chymotrypsin inhibitor; diagnosis design /evaluation; early diagnosis; enzyme activity; enzyme biosynthesis; enzyme complex; enzyme linked immunosorbent assay; human subject; immunochemistry; isozymes; laboratory mouse; laboratory rabbit; macroglobulins; neoplasm /cancer diagnosis; neoplasm /cancer genetics; nucleic acid sequence; oncoproteins; prostate neoplasms; prostate specific antigen; protein sequence; semen; serum; trypsin inhibitors; western blottings; zymogens

Prostate cancer is a major form of cancer in U.S. males. Prostate specific antigen (PSA) serum levels provide a good marker for prostate cancer, but assay of total serum PSA alone cannot distinguish early cancer from a number of other prostatic diseases. Numerous invasive and expensive procedures may be required for diagnosis. Preliminary results of the applicant indicate that PSA exists in different forms in semen and in serum and that different PSA forms are found in the sera of different patients. This proposal requests funding to establish a new independent research area for the applicant, in which the various forms of PSA will be identified, assayed in a large number of patients with borderline elevations of total PSA, and correlated to the diagnosis. The long-term goal is to provide the biochemical and immunochemical basis for clinical assays of forms of PSA that distinguish early prostate cancer from other conditions that cause modestly elevated PSA. It is hypothesized: a) that PSA as an enzyme may have a different role in prostate cancer than in benign conditions of the prostate or prostatitis; b) that the enzyme PSA is secreted in inactive zymogen form, activated under particular pathophysiological conditions, and inactivated by proteolytic cleavage or by combining with available protease inhibitors to form complexes; c) that the local environment and the type of epithelial cells that secrete PSA differ in prostate cancer compared to other syndromes; d) that the activators, proteolytic enzymes and inhibitors to which PSA is exposed differ in cancer compared to other syndromes; e) that the time elapsed between secretion of PSA and its translocation to the blood differs in cancer versus other syndromes; f) that the spectrum of enzymes and inhibitors in prostatic fluid is different from that of blood; and g) that all of the above lead to the generation of different forms of PSA in prostate cancer from those found in other syndromes. The applicant's previous experience in elucidating the molecular forms and inhibitors of other enzymes can be readily applied to the identification and measurement of different forms of PSA in patients. The specific aims include: 1) isolation of PSA from semen, characterization of its reactivity with various protease inhibitors, and preparation of standard PSA-inhibitor complexes; 2) development of sandwich ELISA assays for PSA complexes with any significant inhibitors, including alpha1-antichymotrypsin, protein C inhibitor, alpha2-macroglobulin, and others that may be identified, using standard complexes; 3) identification of different forms of PSA in semen and in blood by immunoblot analysis and sequencing studies; 4) development of antibodies and ELISA-assays specific for particular forms or sequences of PSA; 5) application of immunoblot analysis, sandwich ELISAS and other assays which are developed to large numbers of patient sera, especially those in the borderline PSA range; and 6) correlation of the spectrum and levels of different PSA forms to patient diagnosis to establish clinical usefulness of the assays. The proposed studies also provide novel basic knowledge about PSA and its inhibitors that may help to understand the physiological function and regulation of this enzyme.

前列腺癌是美国男性的一种主要癌症形式。 前列腺 血清特异性抗原 (PSA) 水平是前列腺的良好标志物 癌症，但单独检测血清总 PSA 不能早期区分 许多其他前列腺疾病引起的癌症。 无数的侵入性和 诊断可能需要昂贵的程序。 初步结果 申请人指出 PSA 以不同形式存在于精液中，并且 血清中存在不同的 PSA 形式，并且在不同人群的血清中发现了不同的 PSA 形式。 患者。 该提案要求提供资金建立一个新的独立机构 申请人的研究领域，其中各种形式的PSA将 在大量边缘性患者中进行鉴定和分析 总 PSA 升高，并与诊断相关。 长期来看 目标是为临床提供生化和免疫化学基础 区分早期前列腺癌和其他癌症的 PSA 形式测定 导致 PSA 适度升高的情况。 假设：a) PSA 作为一种酶，在前列腺癌中的作用可能与在前列腺癌中的作用不同。 前列腺良性疾病或前列腺炎； b) PSA酶 以非活性酶原形式分泌，在特定条件下被激活 病理生理条件，并通过蛋白水解裂解或失活 通过与可用的蛋白酶抑制剂结合形成复合物； c) 局部环境和分泌的上皮细胞类型 与其他综合征相比，前列腺癌中的 PSA 存在差异； d) 认为 PSA 所接触的激活剂、蛋白水解酶和抑制剂 癌症与其他综合征相比有所不同； e) 时间已过去 PSA 的分泌与其转移至血液之间的差异在于 癌症与其他综合症； f) 酶谱和 前列腺液中的抑制剂与血液中的抑制剂不同；和 g) 上述所有因素都会导致不同形式的 PSA 的产生 前列腺癌与其他综合征中发现的癌症不同。 申请人的 以前在阐明其分子形式和抑制剂方面的经验 其他酶可以很容易地应用于鉴定和 测量患者不同形式的 PSA。 具体目标 包括： 1) 从精液中分离 PSA，对其特性进行表征 与各种蛋白酶抑制剂的反应性以及标准品的制备 PSA抑制剂复合物； 2) PSA 夹心 ELISA 检测的开发 与任何重要抑制剂的复合物，包括 α1-抗胰凝乳蛋白酶、蛋白 C 抑制剂、α2-巨球蛋白和 使用标准复合物可以识别的其他； 3） 鉴定精液和血液中不同形式的 PSA 免疫印迹分析和测序研究； 4) 抗体的开发 针对特定形式或序列的 PSA 的 ELISA 检测； 5） 免疫印迹分析、夹心 ELISA 和其他检测的应用 是针对大量患者血清而开发的，尤其是那些 PSA 临界范围； 6) 频谱和电平的相关性 不同 PSA 形式对患者诊断的影响，以建立临床 测定的有用性。 拟议的研究还提供了新颖的基础 有关 PSA 及其抑制剂的知识可能有助于理解 该酶的生理功能和调节。