Promoter Methylation of the CDH-13 Gene in the Oral Squamous Cell Carcinoma

CDH-13(T-cadherin), which is one of a kind among the 20 cadherins, can be found mainly in wall of aorta, neuron, spleen, blood vessel etc. It is also called H-cadherin. This structural difference can explain that CDH-13 is thought to play a key role in maintaining mutual relation between extra and intra-cellular environment rather than in cell adhesion. The main function of CDH-13 is to participate in blood vessel function. Additionally, it is known to regulate cell growth and cell contact inhibition. When cells are proliferating, cell surface perceives other cells so that substance such as CDH-13 can inhibit their growth or proliferation resulting in homeostasis without endless proliferation or invasion of connective tissue boundaries. However, tumor cell itself appears to be different from normal cells' growth, invasion or transmission. Therefore, it can be diagnosed that these characteristics are closely related to expression of CDH-13 in tumor cells. This study is to investigate expression of CDH-13 in SCC and its correlation with promoter methylation. 20 of tissue species for the study are excised and gathered from 20 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find development of CDH-13 in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1.Immunohistochemical staining: In normal oral squamous epithelial tissue, strong expression of CDH-13 was found in cell plasma membrane of basal cell layer. On the other hand, in case of low-differentiated oral SCC, development of CDH-13 was hardly seen. 2.The development of CDH-13 gene: In 9 of samples, expression of CDH-13 gene could be seen and 2 of them showed low expression compared to the others. And rest of the 11 samples showed no expression of CDH-13 gene. 3.Methylation of CDH-13 gene: Among 9 samples which expressed CDH-13 gene, 7 of them showed unmethylation. In addition, among 11 samples without CDH-13 gene expression, 10 showed methylation. According to the results stated above, promoter methylation were found in 13 samples(65%) among 20 of oral SCC samples. In low-differentiated SCC, suppression of gene expression could be seen accompanying promoter methylation. These phenomenon of gene expression was proved by immunohistochemical investigation. Finally, for development of oral SCC, conclusions can be made that suppression of CDH-13 played a main role and suppression of gene expression was originated from promoter methylation. Considering this, it is expected that suppression of CDH-13 from promoter methylation to be utilized as a good diagnostic marker of oral SCC.

Inhibitory Effect of Gefitinib on the Proliferation of Lens Epithelial Cells

PURPOSE: To evaluate the effect of Gefitinib used for the treatment of non-small cell lung cancer on the proliferation of the lens epithelial cells and the activities of growth factors. METHODS: The cell samples were divided into a control group cultured in DMEM and three experimental groups. Group I was exposed to Gefitinib for 3 minutes; group II was exposed to growth factors; and for group III growth factors were added to each concentration of Gefitinib. MMT assays, BrdU staining and morphologically observations with a phase-contrast microscope were used to verify the degrees of cell proliferation. Western blot analysis was conducted to confirm the effects of Gefitinib on extracellular signal-regulated kinase phosphorylation and on type I collagen production. RESULTS: Lens epithelial cell proliferation in experimental group I was reduced to 76% and 56% for 1.00 micro M and 10.00 micro M of Gefitinib, respectively. Experimental group II showed a 140% increase in cell proliferation with EGF treatment. Experimental group III exhibited decreased lens epithelial cell proliferation with both EGF (86% and 66%), and TGF-beta2 (78% and 59%). BrdU staining demonstrated a significant decrease in cell proliferation in groups I and III exposed to more than 1.0 micro M Gefitinib, while group II showed an increase compared to the control group. Moreover, Western blot analysis revealed inhibiting effects on ERK phosphorylation and type I collagen production. CONCLUSIONS: In the culture of human lens epithelial cells, Gefitinib inhibited cell proliferation when used at a concentration above 1.00 (M for 3 minutes. Furthermore, the effects of EGF and TGF-beta2 were also inhibited.

The Analysis of Refractive Errors of AMO Array(R) Multifocal Intraocular Lens with SRK II Formula

PURPOSE: To evaluate the accuracy of the SRK II formula for the AMO Array(R) multifocal intraocular lens (Array lens) power calculation according to axial length. In case of refractive error more than +/- 1.0 diopter (D), we compared the accuracy of the SRK II with that of other formulas. METHODS: Participants were 178 eyes (142 patients) received the Array lens. These were divided into 3 subgroups based on axial length. Group I had 21 eyes of short axial length (less than 22.0 mm). Group II had 133 eyes of average axial length (more than 22.0mm below 24.5mm). Group III had 24 eyes of long axial length (more than 24.5mm). The difference between preoperative predicted refractive value and postoperative manifest refractive value were calculated. We compared the accuracy of the SRK II and that of SRK/T, Holladay formulas in case of refractive error more than +/- 1.0D. RESULTS: Three eyes (14.2%) in Group I, 14 eyes (10.5%) in group II and 15 eyes (62.5%) in Group III showed refractive errors more than +/- 1.0D. Fifteen eyes (62.5%) in Group III were significantly reduced to 7 eyes (29.1%) with using SRK/T, Holladay formulas. CONCLUSIONS: SRK II formula had better predictive accuracy in axial length less than 24.5mm with Array lens. But it is better to apply SRK/T or Holladay formulas when axial length is more than 24.5mm.

The Capsular Transplantation in Experimentally Induced Capsule Rupture of Porcine Lens

PURPOSE: We assessed the effect of transplantation of capsule on the change of gross and fine structures of the experimentally induced capsular rupture of porcine lens. METHODS: A rupture of 1.0, 3.0 and 5.0 mm in diameter was made on the anterior capsule of the lens and the anterior capsule was transplanted using lyophilized fibrin adhesive(Greenplast(R)) to cover the rupture. RESULTS: Gross and transmission electron microscopic examinations revealed at day 1, 3 and 7 that the progression of lens opacification was delayed and the stability of microscopic fine structure was less disturbed in the lenses with a rupture of 3.0 mm or less or receiving capsule transplantation less than 4 days after capsule rupture. In the lenses with a rupture of 5 mm or larger or receiving transplantation more than 3 days after capsule rupture, there were no significant differences in gross and microscopic findings between transplantation and control groups CONCLUSION: We applied transplantation concept on the lens. Further studies are needed for transplantation of lens capsule.

The Influence of Phenylephrine, Mydrin-P(R) and Cyclopentolate on Intraocular Pressure Elevation

Pharmacological mydriasis can cause an acute elevation of intraocular pressure without obstruction of angle. A prospective study of 80 normal Korean subjects(149 eyes) and 20 Korean primary open angle glaucoma patients(49 eyes) was performed in order to obtain and compare effects on intraocular pressure, pupil size and aqueous floater by phenylephrine, Mydrin-P(R) and cyclopentolate and to investigate wheather intraocular pressure elevation occurs also in Korean eyes after pupil dilation. Significant pressure elevation(6mmHg or more) was rare in normal subjects while incidence of 25% with Mydrin-P(R) and 50% with cyclopentolate occurred in primary open angle glaucoma patients. Thus, stronger cyclopegics induced intraocular pressure elevation more frequently. Statistically significant correlation between intraocular pressure elevation and aqueous floater did not exist in primary open angle glaucoma patients but only existed with cyclopentolate in normal subjects. Maximum mydriasis by phenylephrine, Mydrin-P(R) and cyclopentolate occurred in 60, 90 and 90 minutes respectively. There is a potential hazard of routine dilation of eyes with cycloplegic agents in primary open angle glaucoma patients in both Korean and occidental eyes.

A Case of Peters' Anomaly

Peters' anomaly is a congenital, central corneal stromal opacity usually associated with a defect in the posterior sttroma and Descemet's membrane and anterior synechiae which extend from the pupillary zone of the iris to the periphery of the corneal opacification. The authors experienced a case of Peters' anomaly which occurred in the right eye of 12-day-old male. Under the slit-lamp examination, the right cornea had a central white corneal opacity with adherence of the iris strands to the leukoma and an opaque lens. Intraocular pressure was within normal limits in both eyes.

A Case of Peters' Anomaly

Peters' anomaly is a congenital, central corneal stromal opacity usually associated with a defect in the posterior sttroma and Descemet's membrane and anterior synechiae which extend from the pupillary zone of the iris to the periphery of the corneal opacification. The authors experienced a case of Peters' anomaly which occurred in the right eye of 12-day-old male. Under the slit-lamp examination, the right cornea had a central white corneal opacity with adherence of the iris strands to the leukoma and an opaque lens. Intraocular pressure was within normal limits in both eyes.