FAP Protein

GM-CSF receptor alpha is a member of the cytokine family of receptors. GM-CSF receptor alpha is found in the pseudoautosomal region of the X and Y chromosomes. GM-CSF receptor alpha has different isoform, with some of the isoforms being membrane-bound and others being soluble. Soluble GM-CSF receptor alpha subunit is a soluble isoform of the GMR alpha that is believed to arise exclusively through alternative splicing of the GMR alpha gene product. The sGMR alpha mRNA is expressed in a variety of tissues, but it is not clear which cells are capable of secreting the protein. Hereditary pulmonary alveolar proteinosis (hPAP) is a rare disorder of pulmonary surfactant accumulation and hypoxemic respiratory failure caused by mutations in GM-CSF receptor alpha, which results in reduced GM-CSF-dependent pulmonary surfactant clearance by alveolar macrophages. While no pharmacologic therapy currently exists for hPAP, it was recently demonstrated that endotracheal instillation of wild-type or gene-corrected mononuclear phagocytes results in a significant and durable therapeutic efficacy in a validated murine model of hPAP.Neuropeptide-associated fibroblast activation protein (FAP) is a homodimeric integral membrane gelatinase belonging to the serine protease family. It is selectively expressed in reactive stromal fibroblasts of epithelial cancers, granulation tissue of healing wounds, and malignant cells of bone and soft tissue sarcomas. This protein is thought to be involved in the control of fibroblast growth or epithelial-mesenchymal interactions during development, tissue repair, and epithelial carcinogenesis. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. Neuropeptide-associated fibroblast activation protein (FAP) may be an important risk factor for neurovascular metastasis in hepatocellular carcinoma. Analysis of The Cancer Genome Atlas (TCGA) database showed that FAP mRNA was highly expressed in most human tumor tissues. The HPA database then verified that FAP was highly expressed in tumor tissues following protein translation. Survival analysis then showed that the level of FAP expression significantly affected the overall survival (OS), progress free interval (PFI), and disease specific survival (DSS) of patients with hepatocellular carcinoma.