Immunohistochemical studies on cytokeratin 8 and 18 expressions in canine cutaneous adnexus and their tumors.

Abstract

The expressions of cytokeratin 8 and 18 (CK8 and CK18) in the normal canine skin (2 cases) and cutaneous adnexal tumors (127 cases) were investigated immunohistochemically. In the normal skin, co-expression of CK8/18 was found in the glandular epithelium of apocrine sweat glands, and single CK8-immunoreactivity was detected occasionally in the external root sheath at the isthmus and suprabulbar regions of the hair follicles. Neoplastic glandular epithelial cells in all apocrine gland tumors (21/21 cases, 100%) had co-expression of CK8/18. In trichoblastomas (27/28 cases, 96%), most neoplastic cells were diffusely positive for CK8, but those were negative for CK18. Single CK8-expression was also observed in basaloid neoplastic cells in several cases of trichoepitheliomas (7/19 cases, 37%) and pilomatricoma (1/7 cases, 14%). In several cases of trichoblastomas (4/28 cases, 14%) and trichoepitheliomas (2/19 cases, 11%), tumor cells forming glandular structures had co-expression of CK8/18. There were no positive reactions for both CK8 and 18 in infundibular keratinizing acanthomas, and sebaceous and hepatoid gland tumors. The present findings indicate that co-expression of CK8/18 is a specific feature of apocrine sweat glands and single CK8-expression represents the natures of external root sheath or pluripotential stem cells. Thus, the combination of CK8- and 18-immunostainings may have the utility to confirm the directions of differentiation in canine cutaneous adnexal tumors providing a reliable hallmark for histopathological diagnoses.

• Authors: Koichiro Kato, Kazuyuki Uchida, Kazumi Nibe, Susumu Tateyama
• Journal: The Journal of veterinary medical science (J Vet Med Sci) Vol. 69 Issue 3 Pg. 233-9 (Mar 2007) ISSN: 0916-7250 [Print] Japan
• PMID: 17409637 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Keratin-18
• Keratin-8

Topics

• Animals
• Dog Diseases (metabolism, pathology)
• Dogs
• Immunohistochemistry (veterinary)
• Keratin-18 (metabolism)
• Keratin-8 (metabolism)
• Neoplasms, Adnexal and Skin Appendage (metabolism, pathology, veterinary)
• Skin Neoplasms (metabolism, pathology, veterinary)
• Sweat Glands (metabolism)