Expression of keratin 13 in human epithelial neoplasms

Abstract

The distribution of the 52 kDa keratin 13 was evaluated immunohistochemically, using the AE8 monoclonal antibody. Various squamous and transitional cell epithelial lesions and representative control tissues were studied. This antibody performed adequately in formalin-fixed and paraffin-embedded tissue, but like keratin immunohistochemistry in general, required protease pretreatment. Keratin 13 was found consistently in the suprabasal layers of squamous epithelia of oral cavity, tonsils, larynx, esophagus, lower female genital tract, and transitional urothelium, but it was absent in the epidermis. Generally, various forms of squamous metaplasia were AE8-positive. In dysplasia, AE8 reactivity was considerably decreased or even absent despite the presence of apparent suprabasal maturation. In differentiated squamous cell carcinomas, AE8 immunoreactivity was usually limited to a few cells in the center of the keratinized foci. However, in 10% of squamous cell carcinomas, a significant number of tumor cells was positive. Only well-differentiated urothelial carcinomas showed AE8 immunoreactivity, while poorly differentiated tumors were negative. Interestingly, a Brenner's tumor showed a high number of AE8-positive epithelial cells. Our results show that the expression of keratin 13, as immunohistochemically determined by AE8 antibody, is significantly down-regulated in squamous cell malignancies. Its possible value as an adjunct to diagnosis of dysplasia should be investigated further.

Increased Expression of Cytokeratins 14, 18 and 19 Correlates with Tumor Progression in the Uterine Cervix

“…CK 13-deficient areas were quite extensive in some instances, prabably reflecting the loss of a suprabasal epithelial phe notype and the acquisition of the basal cell phenotype. This is in agreement with the findings of Malecha and Miettinen [26,27]. The sensitivity of CK 13 in detecting invasive malignancy and intraepithelial neoplasia may be useful for the differential diagnosis of difficult 'border line' cases.…”

Differential Expression of Cytokeratin after Orthotopic Implantation of Newly Established Human Tongue Cancer Cell Lines of Defined Metastatic Ability

“…8, 30 Moll et al stated that a decrease in the CK13 expression was associated with an increase in the grade of malignancy in a transitional cell carcinoma. 31 Schaafsma also observed a decrease in the CK13 expression in higher-grade transitional cell carcinomas, particularly in the areas of muscle invasion.…”

Evaluation of Superficial Oral Squamous Cell Malignancy Based on Morphometry and Immunoexpression of Cytokeratin 13 and Cytokeratin 17

“…CK13 is a differentiation-specific cytokeratin which is paired with cytokeratin 4 and expressed in normal oral squamous epithelia outside basal layers [11]. Ohkura et al [18] reported that CK13 expression levels were lower in oral squamous cell carcinoma and severe epithelial dysplasia than in mild and moderate epithelial dysplasia, and several additional studies have since reported that CK13 expression decreases with increasing severity of epithelial dysplasia [12,13,19].…”

“…A multitude of studies have found significant relationships between malignancy and the expression levels of CK13 and CK17, indicating that combined assessment of CK13 and CK17 expression status might be a highly reliable diagnostic test to identify malignant transformation of oral epithelial dysplasia and oral squamous cell carcinoma [11,12,13,14,15,16,17,18,19,20]. However, it was previously unknown whether the expression status of CK13 or CK17 correlates with the morphological signs of atypia in superficial oral squamous cells collected by oral exfoliative cytology.…”

“…Recent molecular and immunohistochemical studies have shown that cytokeratin 13 (CK13) and cytokeratin 17 (CK17) are useful biomarkers for oral malignant lesions and are valuable adjuncts to conventional histological evaluation [11,12,13,14,15,16,17,18,19,20]. …”