Astroprincin (FAM171A1, C10orf38)

Abstract

Our group originally found and cloned cDNA for a 98-kDa type 1 transmembrane glycoprotein of unknown function. Because of its abundant expression in astrocytes, it was called the protein astroprincin (APCN). Two thirds of the evolutionarily conserved protein is intracytoplasmic, whereas the extracellular domain carries two N-glycosidic side chains. APCN is physiologically expressed in placental trophoblasts, skeletal and hearth muscle, and kidney and pancreas. Overexpression of APCN (cDNA) in various cell lines induced sprouting of slender projections, whereas knockdown of APCN expression by siRNA caused disappearance of actin stress fibers. Immunohistochemical staining of human cancers for endogenous APCN showed elevated expression in invasive tumor cells compared with intratumoral cells. Human melanoma cells (SK-MEL-28) transfected with APCN cDNA acquired the ability of invasive growth in semisolid medium (Matrigel) not seen with control cells. A conserved carboxyterminal stretch of 21 amino acids was found to be essential for APCN to induce cell sprouting and invasive growth. Yeast two-hybrid screening revealed several interactive partners, of which ornithine decarboxylase antizyme-1, NEEP21 (NSG1), and ADAM10 were validated by coimmunoprecipitation. This is the first functional description of APCN. These data show that APCN regulates the dynamics of the actin cytoskeletal and, thereby, the cell shape and invasive growth potential of tumor cells.

<p>Identification of Important Modules and Biomarkers in Breast Cancer Based on WGCNA</p>

“…16 Studies showed that FAM171A1 can regulate the cell morphology and invasive growth potential of tumor cells by regulating the dynamics of the actin cytoskeleton. 17 The study conducted by Sanawar et al demonstrated that miR590-5p is a target of ERα in ER receptor-positive BRCA. ERα can stimulate the expression of miR590-5p, and subsequently down-regulated that of FAM171A1 in ERα-positive BRCA cells.…”

Impact of Astroprincin (FAM171A1) Expression in Oral Tongue Cancer

“…APCN is also expressed in some malignancies, such as nodular melanoma and lobular breast cancer [13]. Higher APCN expression was seen in the tumor invasive front than in the intra-tumoral cells [13]. The authors showed that upregulated APCN expression induced an invasive growth pattern, with sprouting of slender-like projections in melanoma cells [13].…”

“…Rasila et al [13] recently characterized a novel endogenous protein called astroprincin (APCN, also known as FAM171A1) that is abundant in brain astrocytes. APCN is an evolutionarily conserved 98-kDa transmembrane type I glycoprotein.…”

“…APCN is an evolutionarily conserved 98-kDa transmembrane type I glycoprotein. APCN is expressed in placental trophoblasts, kidneys, pancreas and heart muscle [13]. APCN is also expressed in some malignancies, such as nodular melanoma and lobular breast cancer [13].…”

“…APCN is expressed in placental trophoblasts, kidneys, pancreas and heart muscle [13]. APCN is also expressed in some malignancies, such as nodular melanoma and lobular breast cancer [13]. Higher APCN expression was seen in the tumor invasive front than in the intra-tumoral cells [13].…”