Breast cancer-associated pS2 protein: synthesis and secretion by normal stomach mucosa.
The human pS2 gene is specifically expressed under estrogen transcriptional control in a subclass of estrogen receptor-containing human breast cancer cells. The pS2 gene encodes an 84-amino acid protein that is secreted after signal peptide cleavage. The distribution of pS2 protein in normal human tissues was studied with antibodies to pS2; pS2 was specifically expressed and secreted by mucosa cells of the normal stomach antrum and body of both female and male individuals. Moreover, no estrogen receptor could be detected in these cells, indicating that pS2 gene expression is estrogen-independent in the stomach. The function of the pS2 protein in the gastrointestinal tract is unknown. However, the pS2 protein is similar in sequence to a porcine pancreatic protein that has been shown to inhibit gastrointestinal motility and gastric secretion.
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D001943:Breast Neoplasms / Q000378:metabolism*; D004967:Estrogens / Q000494:pharmacology; D005091:Exons; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D005786:Gene Expression Regulation; D006651:Histocytochemistry; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D011506:Proteins; D012333:RNA, Messenger / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014018:Tissue Distribution; D000071163:Trefoil Factor-1; D014407:Tumor Cells, Cultured; D025521:Tumor Suppressor Proteins
D000911:Antibodies, Monoclonal; D004967:Estrogens; D009363:Neoplasm Proteins; D011506:Proteins; D012333:RNA, Messenger; D011960:Receptors, Estrogen; C051838:TFF1 protein, human; D000071163:Trefoil Factor-1; D025521:Tumor Suppressor Proteins