Immunofluorescence examination of CK-13 expression in cell line KB differentiated by all-trans retinoic acid or As2 O3 / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To examine the expression of cytokeratin-13 (CK-13) in oral squamous cell carcinoma (OSCC) and to discuss the effects of all-trans retinoic acid (ATRA) or arsenic trioxide (As2 O3) on the differentiation of human oral undifferentiated squamous cell carcinoma cell line KB cells.</p><p><b>METHODS</b>The cultured KB cells were divided into three groups, ATRA group, As2 O3 group, and control. The expression of CK-13 in KB cells was detected using the immunofluorescence before and after KB cells were induced by ATRA or As2 O3.</p><p><b>RESULTS</b>The expression rates of CK-13 in KB cells in the ATRA group and As2 O3 group were significantly higher than that in the control (P < 0.05), but there was no significant difference in the expression between ATRA and As2 O3 group(P > 0.05).</p><p><b>CONCLUSIONS</b>ATRA and As2 O3 both have the ability to differentiate the KB cells, and the expression is associated with the degree of tumor differentiation. CK-13 may serve as a molecular marker to evaluate the effect of the differentiation treatment on OSCC.</p>

Correlation between the expression of cytokeratin-18-mRNA and invasion and metastasis of oral squamous cell carcinoma / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the expression of cytokeratin (CK)-18 and biological behavior of oral squamous cell carcinoma (OSCC).</p><p><b>METHODS</b>Twenty-three patients with OSCC were investigated for the expression of CK-18-mRNA by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Correlations between clinical stages, pathological differentiation, lymphatic metastasis and the expression of CK-18-mRNA were evaluated. CK-18-mRNA expression of peripheral blood from the 23 patients and 23 healthy people were also examined. During follow-up after operation, the peripheral blood was collected again for the expression of CK-19-mRNA.</p><p><b>RESULTS</b>Expression of CK-18-mRNA was found in 16 patients. The expression of CK-18-mRNA was significantly associated with clinical stages, tumor differentiation and lymphatic metastasis. CK-18-mRNA was positive in 4 of 23 blood specimens before operation, but during follow-up only 1 of 23 patients was still positive in peripheral blood.</p><p><b>CONCLUSIONS</b>CK-18 may provide additional information in forecasting the metastasis of OSCC and serve as a reference in monitoring recurrence.</p>

Glandular odontogenic cyst: report of two cases with cytokeratin 18 expression / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To report two cases of glandular odontogenic cyst and examine its cytokeratin 18,19 expression.</p><p><b>METHODS</b>Two cases of glandular odontogenic cyst were reported and studied. The cytokeratin 18, 19 expression in these two cases were also investigated using immuno-histochemical staining as well as in the situ hybridization of the cyst epithelium.</p><p><b>RESULTS</b>Histo-pathological examination revealed that ciliated columnar cells, squamous cells and low-columnar cells were found in the superficial layer of the lining epithelium. Several minor salivary glands, mainly composed of seromucous cells were observed near the satellite cyst. CK18 were expressed in all layers of the lining epithelium of varying intensity. CK18 was negative in lining epithelium of the daughter cyst, but CK19 was positive. CK18-mRNA was expressed in all the layers of the lining epithelium, the salivary glands and daughter cysts.</p><p><b>CONCLUSIONS</b>Histological features and CK18 expression may be indicative of the possibility of salivary glandular and odontogenic differentiation.</p>

Cytokeratin 18 and their gene expression in jaw odontogenic keratocyst epithelial lining / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To examine cytokeratin 18(CK18) and it's gene in jaw odontogenic keratocyst (OKC) epithelial lining.</p><p><b>METHODS</b>The epithelial linings of 32 cases were subject to monoclonal antibody immunohistochemical staining for CK18, CK8 and CK19. RT-PCR and in situ hybridization for CK18 mRNA were conducted in 12 of 32 cases in keratocyst epithelial cell linings.</p><p><b>RESULTS</b>In 17 cases, CK18 were observed in keratinized surface layers, though weakly positive. In 27 cases, CK18 were positive in the granular cell layers. CK18 were also positive in the spinous cell layers in 14 cases. In all cases, CK18 was negative in basal cell layers. By RT-PCR, 4 cases expressed CK18 strongly, 8 cases weakly. By in situ hybridization, 8 cases expressed CK18 mRNA positively in both spinous and granular cell layers, and 4 cases positively in basal and keratinized cell layers. CK8 were expressed in basal cell layers of keratocyst epithelial linings. In 23 cases, CK19 were expressed in surface cell layers of keratocyst epithelial linings.</p><p><b>CONCLUSION</b>The expression of CK18 in keratocyst epithelial linings transfers from basal cell layer to spinous layer. The expression of CK18 immunohistochemical staining and CK18 mRNA in situ hybridization are different, which shows CK18 might be related to proliferation of OKC epithelial linings. That suggests the existence of regulation of CK18 and CK18 mRNA expression.</p>

Cytokeratin18, 13 and their gene expression in post-operative maxillary cyst linings with metaplastic epithelium / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To study the cytokeratin 18 and 13 and their gene (CK) expression in post-operation maxillary cyst linings with metaplastic epithelium.</p><p><b>METHODS</b>CK expressions were examined with immunohistochemistry in 46 post-operative maxillary cyst (POMC) which were lined with pseudostriated columnar cells only (13 cases), both kinds of columnar and squamous cells (30 cases) and squamous cells only (3 cases).</p><p><b>RESULTS</b>The expressions of CK8, CK13 and CK18 were observed in 39, 9 and all of the 43 columnar epithelial linings, respectively. Metaplastic squamous epithelia expressed more CK13 and less CK18 and CK8. Of the 33 metaplastic linings, 24 expressed CK8, 23 CK13 and 26 linings expressed CK18. The expression of CK13- and CK18-mRNA was generally correlated with the protein expression level. By in situ hybridization, CK18-mRNA expression was observed not only in 26 metaplastic linings which were positive for CK18 protein but also in five of the seven metaplastic linings which did not express CK18 protein. In addition, RT-PCR revealed an expression of CK18-mRNA in all metaplastic squamous linings although the expression level was weaker than that in the columnar epithelial linings. The CK13-mRNA was expressed in a fashion inverse to the CK18-mRNA.</p><p><b>CONCLUSIONS</b>These results indicate that CK18-mRNA is preserved through metaplasia although the protein expression decreases and metaplastic squamous cells differentiate with a decrease of CK18 and an increase of CK13 expression.</p>