Author/Editor     Kosmehl, Hartwing; Berndt, Alexander; Haas, Karl Michael; Hyckel, Peter
Title     Laminin-5. A potential tool in diagnosis of head and neck squamous cell carcinoma
Translated title     Pomen laminina-5 v diagnostiki ploščatoceličnega karcinoma glave in vratu
Type     članek
Source     Zdrav Vestn
Vol. and No.     Letnik 71, št. Suppl 3
Publication year     2002
Volume     str. III-45-7
Language     eng
Abstract     The heterotrimeric extracellular matrix protein laminin-5 (In-5) is a regular constituent of the basement membrane in oral and pharyngeal mucosa consisting of the a3, b3 and y2 chain. On the one hand, it is an integral part of the epithelial adhesion complex which connects the hemidesmosomes of the basal cells with the basement membrane. In this position, In-5 strictly acts against migration and invasion and may fundamentally contribute to the distinction between intraepithelial neoplasia vs. invasive carcinoma. On the other hand, single chains of In-5, in particular the y2 chain, are able to promote migration. The immunohistochemical In-5 demonstration outside the basement membrane in the keratinocyte cytoplasm or in the stroma of the invasive front, as well as In-5 synthesis, indicate epithelial cells potentially able to migrate and to invade. The extent of the In-5 demonstration outside the basement membrane, as well the loss of In-5 from the basement membrane, is therefore of prognostic value. A diagnostic interpretation of In-5 immunostainings has to consider the contrary functions of In-5 or In-5 fragments: within the basement membrane it acts as anchoring protein and outside the basement membrane it represents a migration/invasion factor.
Summary     Heterotrimerni protein izvenceličnega matriksa laminin-5 (ln-5) je sestavni del bazalne membrane sluznice ustne votline in žrela in je grajen iz verig a3, b3 in z3. Ln-5 je sestavni del epitelijskega adhezijskega kompleksa, ki povezuje hemidezmosome bazalnih celic z bazalno membrano. V tem položaju In-5 dosledno zavira migracijo in invazijo in tako pomaga pri razločevanju med intraepitelijskim in invazivnim karcinomom. Na drugi strani posamezne verige In-5, še posebej veriga Y2, lahko vzpodbujajo migracijo. Imunohistokemični prikaz In-5 izven bazalne membrane (v citoplazmi keratinocitov ali v stromi na invazijskem robu tumorja) in sinteza In-5 kažeta na možnost migracije epitelijskih celic in invazijo. Zato imata intenzivnost imunohistokemičnega prikaza In-5 izven bazalne membrane kot tudi izginjanje In-5 iz bazalne membrane napovedano vrednost. V diagnostičnem ocenjevanju imunohistokemičnega prikaza In-5 je potrebno upoštevati nasprotujoči funkciji In-5 in njegovih sestavnih delov:v bazalni membrani delije kot sidrna beljakovina, izven nje pa kot dejavnik migracije in invazije.
Descriptors     HEAD AND NECK NEOPLASMS
CARCINOMA, SQUAMOUS CELL
LAMININ
BASEMENT MEMBRANE
DESMOSOMES