This project will develop a radioimmunoassay kit for Endocrine Secretory Protein (ESP) for use as a serum marker for endocrine cancer. ESP is the name given to the protein previously referred to as parathyroid secretary protein (PSP) and Chromogranin A (Chr A). Studies indicate that ESP is a tissue and serum marker for a wide variety of hormone-producing tumors. With iinmunochemical and biochemical techniques, researchers have identified ESP in normal and/or neoplastic tissue of the adrenal, pituitary, pancreas, hypothalamus, thyroid, and parathyroid neoplasms, as demonstrated by radioimmunoassay-increased serum concentrations of ESP in patients with tumors of these endocrine glands. Similar observations have been made in patients with horrnone-producing tumors of nonendocrine tissue, such as carcinoma of the lung and GI tract.The research radioimmunoassay procedure developed for ESP will be used as the basis for a kit for the measurement of this protein. Protocols and reagents currently in use will provide the basis for the development work. These reagents, which are currently used in the research assay for ESP, will be adapted to a kit format. Thus emphasis will be placed on developing stable and adequate reagents suitable for kit use and developing assay protocols which are reproducible and convenient to use. Each stage of assay development will be evaluated. Similarly, all kit prototypes as well as the final kit forinat will be evaluated.This kit could be widely available for clinical studies. These studies should help to establish new procedures for the early and specific diagnosis of cancer and provide guides to patient management.National Cancer Institute (NCI)
