The claudins are a family of over twenty proteins which are components of the tight junction (Latin claudere, to close). They are found with other components including occludin and junctional adhesion molecule, and interact with scaffold proteins, ZO-1, ZO-2 and ZO-3. The claudins constitutes a variable component, with specific claudins being associated with specific tissues.

Immunohistochemical expression

A number of tumours which form the differential from perineuromas are negative for Claudin-1:





11/121, 22/762

dermatofibrosarcoma protuberans


low-grade fibromyxoid sarcoma


desmoplastic fibroblastoma









CNS tumours

atypical teratoid/rhabdoid tumour

7/74, 17/595, 12/316  
Germinoma 2/26
PNET 1/26
Meningioma 1/106
Medulloblastoma 1/246
Choroid plexus tumour 0/116
Pilocytic astrocytoma 0/216
Astrocytoma (grade II/III) 0/146
Ganglioglioma 0/136
Glioblastoma 0/126
Ependymal tumours 0/126
Dysembryoplastic neuroepithelial tumours 0/86
Oligodendrogliomas 0/86
Craniopharyngioma 0/46
Central neurocytoma 0/26
non-CNS tumours Malignant rhabdoid tumour 7/166
Wilms tumour 5/106
Hepatoblastoma 1/96
Alveolar rhabdomyosarcoma 0/96
Embryonal rhabdomyosarcoma 0/106
Synovial sarcoma 0/106
Ewings sarcoma 0/96
Neuroblastoma 0/106  


Diagnostic utility


1 Folpe, A.L., Billings, S.D., McKenney, J.K., Walsh, S.V., Nusrat, A. and Weiss, S.W. Expression of claudin-1, a recently described tight junction-associated protein, distinguishes soft tissue perineurioma from potential mimics. Am J Surg Pathol 2002;26:1620-6.

2 Hornick JL,Fletcher CD. Soft tissue perineurioma: clinicopathologic analysis of 81 cases including those with atypical histologic features. Am J Surg Pathol 2005; 29:845-58

3 Karanjawala ZE, Illei PB, Ashfaq R, et al. New markers of pancreatic cancer identified through differential gene expression analyses: claudin 18 and annexin A8. Am J Surg Pathol 2008; 32:188-96

4 Birks DK, Kleinschmidt-DeMasters BK, Donson AM, Barton VN, McNatt SA, Foreman NK, et al. Claudin 6 is a positive marker for atypical teratoid/rhabdoid tumors. Brain Pathol. 2010 Jan;20(1):140-50.

5 Antonelli M, Hasselblatt M, Haberler C, Di Giannatale A, Garre ML, Donofrio V, et al. Claudin-6 is of limited sensitivity and specificity for the diagnosis of atypical teratoid/rhabdoid tumors. Brain Pathol. 2011 Sep;21(5):558-63.

6 Sullivan LM, Yankovich T, Le P, Martinez D, Santi M, Biegel JA, et al. Claudin-6 is a nonspecific marker for malignant rhabdoid and other pediatric tumors. Am J Surg Pathol. 2012 Jan;36(1):73-80.

This page last revised 6.3.2012.

©SMUHT/PW Bishop