Serum progastrin-releasing peptide

Serum gastrin-releasing peptide precursor is used to assist in the diagnosis of cancer, but the presence of cancer cannot be determined solely based on serum gastrin-releasing peptide precursor. It is necessary to make a judgment based on the patient's daily performance and other diagnostic data at the same time, so that the results obtained are not arbitrary. The following will introduce some specific clinical significance of serum gastrin-releasing peptide precursor and other related contents.

Clinical significance:

Gastrin-releasing peptide is an important regulatory molecule that is related to many physiological functions and pathological conditions of the human body. It is a gastrointestinal hormone and the mammalian homologue of amphibian bombesin, originally isolated from pig gastric mucosa and widely distributed in the nervous system, gastrointestinal tract and respiratory tract of mammals.

Following the dissociation of the signal peptide, its 148 amino acid preproprotein is further broken down to generate 27 amino acid gastrin-releasing peptide and 68 amino acid gastrin-releasing peptide precursor (ProGRP). Because GRP has a short half-life of only two minutes and is impossible to detect in the blood, an assay was developed to detect pro-GRP, a carboxy-terminal region common to the three types of human pro-GRP splice variants.

Progastrin-releasing peptide and neuron-specific enolase are two molecules associated with neuroendocrine tissues of origin and tumors. Elevated levels of progastrin-releasing peptide are seen in a variety of tumors of neuroendocrine origin, including small cell lung cancer, carcinoid, undifferentiated large cell lung cancer with neuroendocrine features, medullary thyroid carcinoma, other neuroendocrine malignancies, and a subset of androgen-independent prostate cancer with neuroendocrine features.

1. ProGRP in benign diseases:

Literature reports that the normal ProGRP serum concentration is 2-50pg/ml. However, in a study of patients with benign diseases including liver disease (excluding renal insufficiency), 2.5% of patients had ProGRP serum levels >50 pg/ml. ProGRP was <80pg/ml in all patients. Renal insufficiency was the only cause of elevated levels of this tumor marker.

2. ProGRP in Lung Cancer:

ProGRP is a specific tumor marker for small cell lung cancer, but elevated levels can also be seen in a small number of patients with non-small cell lung cancer. The ProGRP concentrations in these patients were significantly lower than those in patients with small cell lung cancer. The serum concentration of ProGRP is related to the degree of tumor infiltration. When ProGRP>150pg/ml, the possibility of small cell lung cancer is>93%.