Distribution of basement membrane type IV collagen alpha chains in ameloblastoma: an immunofluorescence study.
BACKGROUND
Type IV collagen, a heterotrimeric molecule that exists in six genetically distinct forms, alpha1(IV)-alpha6(IV) is a major structural component of basement membrane (BM) and acts as a scaffold for other BM constituents.


METHODS
Indirect immunofluorescence using alpha chain-specific monoclonal antibodies was employed to clarify basement membrane (BM) collagen IV distribution in two ameloblastoma, and for comparison, on oral mucosa and tooth germ.


RESULTS
Ameloblastoma BM expressed five of six genetically distinct forms of collagen IV: alpha1(IV), alpha2(IV), alpha5(IV) and alpha6(IV) chains occurred as intense linear stainings without disruption around neoplastic epithelium, and this expression pattern was fundamentally similar to oral mucosa BM; alpha4(IV) expression was rare and occurred around nests of primitive tumor cells or potentially invasive sites. The tooth germ demonstrated a stage- and position-specific collagen IV distribution: the inner enamel epithelium BM expressed alpha1(IV), alpha2(IV), and alpha4(IV) except in the cuspal predentine region; and the outer enamel epithelium BM expressed alpha1(IV), alpha2(IV), alpha5(IV), and alpha6(IV) chains.


CONCLUSIONS
Results suggest that collagen IV alpha chain distribution in ameloblastoma BM plays an important role in tumor cytodifferentiation and progression.
Nakano
Keisuke
K
Department of Oral Pathology and Medicine, Graduate School of Medicine and Dentistry, Okayama University, Okayama, Japan.
Siar
Chong Huat
CH
Nagai
Noriyuki
N
Naito
Ichiro
I
Sado
Yoshikazu
Y
Nagatsuka
Hitoshi
H
Hoh
Choufuku
C
Kurada
Katsuhiro
K
Tsujigiwa
Hidetsugu
H
Gunduz
Mehmet
M
D000564:Ameloblastoma / Q000473:pathology*; D000911:Antibodies, Monoclonal; D001485:Basement Membrane / Q000473:pathology; D002454:Cell Differentiation; D024141:Collagen Type IV / Q000032:analysis* / Q000145:classification; D004396:Coloring Agents; D003743:Dental Enamel / Q000473:pathology; D003804:Dentin / Q000473:pathology; D018450:Disease Progression; D004848:Epithelium / Q000473:pathology; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008339:Mandibular Neoplasms / Q000473:pathology*; D008856:Microscopy, Fluorescence; D009061:Mouth Mucosa / Q000473:pathology; D014083:Tooth Germ / Q000473:pathology
D000911:Antibodies, Monoclonal; D024141:Collagen Type IV; D004396:Coloring Agents