Alterations of FHIT and P53 genes in keratocystic odontogenic tumor, dentigerous and radicular cyst.

BACKGROUND: The purpose of this study was to determine fragile histidine triad (FHIT) and p53 protein expression, and to analyze FHIT and p53 gene status in keratocystic odontogenic tumor (KOT), dentigerous cysts (DC) and radicular cysts (RC). METHODS: The methods used were immunohistochemistry and molecular genetic methods including loss of heterozygosity (LOH) and gene sequencing. RESULTS: FHIT protein expression was different among groups. Aberrant expression was the highest in KOT, then in RC and DC. p53 protein expression was different among groups. LOH in paraffin-embedded specimens was detected in 22.6% and 12.9% for FHIT and p53 respectively. Mutation of p53 gene at codon 237 was observed in only two specimens (one KOT and one DC). Of the six frozen specimens, three exhibited FHIT gene LOH (two RC and one KOT). KOT showed loss of exons 6-7 at FHIT locus and mutation at codon 237 at p53 locus, but this could be a chance result. CONCLUSION: Aberrations of FHIT and p53 genes/proteins could be considered markers responsible for the development of odontogenic lesions.

[Cytokeratin18, 13 and their gene expression in post-operative maxillary cyst linings with metaplastic epithelium].

OBJECTIVE: To study the cytokeratin 18 and 13 and their gene (CK) expression in post-operation maxillary cyst linings with metaplastic epithelium. METHODS: 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). RESULTS: 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. CONCLUSIONS: 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.

Free radicals and SOD activity of jaw cyst. Direct measurement and spin trapping studies by ESR.

Free radicals produced in the fluid of jaw cysts were directly measured at room temperature using ESR. With these samples, SOD activity of the cyst fluid was measured by the ESR spin trapping method with DMPO as a trapping agent. Freeze-dried samples of cyst fluid showed a broad ESR signal at g = 2.005. Relative signal intensity of samples from jaw cysts with inflammation was higher than jaw cysts without inflammation. SOD activity of cyst fluid with high viscosity showed higher values than that of cyst fluid with low viscosity. We suggest that free radicals produced in jaw cyst damage tissues while higher SOD activity of cyst fluid play a role in a self-defense mechanism against free radicals.

[The correlation between the derivatives of the arachidonic acid cascade and oral pathology. A review of the literature]. / Correlazione tra i derivati della cascata dell'acido arachidonico e la patologia orale. Revisione della letteratura.

The effects of several metabolites deriving from the arachidonic acid cascade on oral tissues are reviewed. These include the effects on the pulp, tissues and gingiva, and on the development of radicular cysts and epithelial tumours of the oral cavity.

Lectin-binding patterns in epithelial lining of jaw cysts.

Lectin-binding patterns were examined in epithelial walls of 65 jaw cysts (30 post-operative maxillary cysts: POMCs, 20 radicular and 15 follicular cysts), and characteristic lectin staining for each kind of jaw cysts is presented. Between squamous and columnar epithelia, the staining intensity of WGA, Con A and UEA-I was not different, but SBA bound more remarkably to squamous than to columnar epithelia. In both epithelia the outer layers did react more strongly with the lectins examined. Concerning odontogenic cysts, the lectin-binding affinities of outer and intermediate layer cells were nearly the same in both follicular and radicular cysts. Basal cells of radicular cyst walls were however, more markedly positive for lectin binding than of follicular cysts. Furthermore, basal cells of keratinized (RKSE 60 keratin-positive) epithelium were inferior to those of non-keratinized linings in the bindings. Lectin-binding patterns of metaplastic squamose epithelia of POMCs which were positive for RGE53-keratin (principally columnar epithelium-specific keratin) were similar to originally squamous linings of odontogenic cysts. Columnar linings of unusual radicular cysts were positively stained with SBA. By these results, lectin-binding sugar residues of the epithelium seem to be related to the epithelial morphology.

Treatment of jaw cysts with an irrigational method. (II). The effect on the nature of cyst walls and surrounding bone.

Cysts in jaws are generally excised by Partsch II when they are small. When they are large, they are excised by Partsch I to form a paranasal sinus in an oral cavity, or by an operation based on Caldwell-Luc's method to form it from nostrils, as Partsch II forms dead space after the operation and the cyst increases by the pressure of intracystic fluid. However, with Partsch I, the bone needs many days to regenerate, and since a surgical ciliated cyst of the maxilla is often formed after an operation of the maxillary sinus, Partsch I is not necessarily a good method. Therefore, in order to control cyst inflammation, the irrigation of cyst cavities was repeated, as it is held that prostaglandin-like (PG-like) substances are generated in the cyst walls when a cyst is inflamed by bacterial infection; prostaglandin E2 (PGE2) especially acts on the resorption of bone and enlarges the cyst. As a result of repeated irrigations, infection of the cyst cavities disappeared simultaneously with decreasing the pressure of intracystic cavities, the values of thiobarbituric acid, Prostaglandin E, Prostaglandin F2 alpha (TBA, PGE, PGF2 alpha), and the free radical intensity at g = 2.003 decreased. The bone regenerated around the cyst walls, and finally the cyst diminished in size. In the case of the viscous cyst fluids, a solution containing hyaluronidase enabled complete disappearance. It would be better to apply Partsch II after the cyst has become smaller through irrigation. After the irrigational method, irregular formation and tendency toward malignancy could be found in none of the cyst wall cells.

A biochemical study of the nature of jaw cysts (II). The role of lipids in the enlargement of cysts.

It is believed that cysts in jaws enlarge when the permeability of the cyst wall changes, that the proteins of cyst fluid increase, and that the intracystic fluid pressure on the jaw bone increases because of inflammation. On the other hand, it is also believed that cysts enlarge when a prostaglandin-like substance, which is generated in the wall, acts chemically in the resorption of the jaw bone. This investigation comprised 97 cases of various jaw cysts. The author attempted to treat 91 of these cases by the irrigation method. Lipids and related substances in cyst walls removed at operation in 15 cases, and cyst fluid were examined in all cases as follows. Their identification with IR, analyses of fatty acids with GC, and estimation of the free radical concentration by ESR were carried out. As a result, it was found that in an infected cyst wall the values of phospholipids, TBA and the free radical concentration increased, and that the value of arachidonic acid decreased. In cyst fluid there was no LCAT activity, the value of HDL-cholesterol decreased, and free cholesterol crystals were detected. After irrigation of cyst cavities, cholesterol esters were detected. In infected cyst fluid, the values for white corpuscles, TBA, and the free radical concentration increased, whereas the values of PO2, arachidonic acid, and SOD decreased. As the infection disappeared, these values were reversed. Finally the cysts diminished in size. The author assumes that jaw cyst enlargement is related to LPO and PG-like substances produced by lipid peroxidation of the cyst wall and fluid.

[Antibacterial concentrations in serum and tooth-jawbone tissue following perioperative administration of propicillin]. / Antibakterielle Konzentrationen in Serum und Geweben aus dem Zahn-Kieferbereich nach perioperativer Einnahme von Propicillin.

Antibacterial Concentrations in Serum and Dental Tissues after Preoperative Application of Propicillin. After resecting radicular and follicular cysts in the jaws, the serum, bone, capsule and fluid of the cysts from 40 patients were studied for their propicillin concentration. The patients received 1 Mega unit (0.7 g) propicillin orally as oblong tablets one or two hours before surgery. One or two hours after the application of propicillin, the distribution coefficients between serum and the three tissues were 0.78 and 0.87 for the spongious bone, 0.07 and 0.06 for the cyst capsule and 0.14 and 0.08 for the cyst fluid. The mean concentrations in all three tissues were distinctly above the MICs of the bacteria most frequently isolated from the mouth for at least two hours.