title: Distribution and variable expression of secretory pathway protein reticulocalbin in normal human organs and non-neoplastic pathological conditions.
abstract: Reticulocalbin (RCN) is one member of the Ca(2+)-binding proteins in the secretory pathway and is localized in the endoplasmic reticulum. RCN may play a role in the normal behavior and life of cells, although its detailed role remains unknown. Overexpression of RCN may also play a role in tumorigenesis, tumor invasion, and drug resistance. The new antibody for human RCN is used in the distribution of RCN in normal human organs of fetuses and adults with or without inflammation. Immunohistochemical examination demonstrated a broad distribution of RCN in various organs of fetuses and adults, predominantly in the endocrine and exocrine organs. However, RCN expression was heterogeneous in each constituent cell of some organs. Among non-epithelial organs, vascular endothelial cells, testicular germ cells, neurons, and follicular dendritic cells showed strong staining. Plasma cells were the only RCN-positive cells among hematopoietic and lymphoid cells. In inflammatory conditions, RCN expression was enhanced in both epithelial and non-epithelial cells. Heterogeneous expression of RCN indicates that the amount of RCN needed for cell behavior and life may be variable, depending on each cell type and, therefore, RCN may be helpful in establishing the cell origin of neoplasms in some organs. However, further study is needed to establish the significance of RCN in tumorigenesis and in some peculiar features of neoplasms.
authors.affiliation: Second Department of Pathology, Fukushima Medical University School of Medicine, Hikarigaoka 1, 960-1245, Fukushima, Japan. doraemon@fmu.ac.jp
authors.forename: Takeaki
authors.initials: T
authors.lastname: Fukuda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Oyamada
authors.forename: Takuma
authors.initials: T
authors.lastname: Isshiki
authors.forename: Masahiro
authors.initials: M
authors.lastname: Maeda
authors.forename: Takashi
authors.initials: T
authors.lastname: Kusakabe
authors.forename: Ayumi
authors.initials: A
authors.lastname: Hozumi
authors.forename: Tomiko
authors.initials: T
authors.lastname: Yamaguchi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Igarashi
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Hasegawa
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Seidoh
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D000328:Adult; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D011230:Precancerous Conditions / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D002135:Calcium-Binding Proteins; C078865:reticulocalbin