MicroRNA Analysis during Cultured Odontoblast Differentiation

MicroRNAs (miRNAs, miRs) are about 21-25 nucleotides in length and regulate mRNA translation by base pairing to partially complementary sites, predominantly in the 3'-untranslated region (3'-UTR) of the target mRNA. In this study, the expression profile of miRNAs was compared and analyzed for the establishment of miRNA-related odontoblast differentiation using MDPC-23 cells derived from mouse dental papilla cells. To determine the expression profile of miRNAs during the differentiation of MDPC-23 cells, we employed miRNA microarray analysis, quantitative real-time PCR (qRT-PCR) and Alizaline red-S staining. In the miRNA microarray analysis, 11 miRNAs were found to be up- or down-regulated more than 3-fold between day 0 (control) and day 5 of MDPC-23 cell differentiation among the 1,769 miRNAs examined. In qRT-PCR analysis, the expression levels of two of these molecules, miR-194 and miR-126, were increased and decreased in the control MDPC-23 cells compared with the MDPC-23 cells at day 5 of differentiation, respectively. Importantly, the overexpression of miR-194 significantly accelerated mineralization compared with the control cultures during the differentiation of MDPC-23 cells. These results suggest that the miR-194 augments MDPC-23 cell differentiation, and potently accelerates the mineralization process. Moreover, these in vitro results show that different miRNAs are deregulated during the differentiation of MDPC-23 cells, suggesting the involvement of these genes in the differentiation and mineralization of odontoblasts.

MicroRNA Analysis in Normal Human Oral Keratinocytes and YD-38 Human Oral Cancer Cells

MicroRNAs (miRNAs) are small non-coding RNAs that mediate gene expression at the post-transcriptional level by degrading or repressing targeted mRNAs. These molecules are about 21-25 nucleotides in length and exert their effects by binding to partially complementary sites in mRNAs, predominantly in the 3'-untranslated region (3'-UTR). Recent evidence has demonstrated that miRNAs can function as oncogenes or tumor suppressors through the modulation of multiple oncogenic cellular processes in cancer development, including initiation, cell proliferation, apoptosis, invasion and metastasis. In our present study, we examined the expression profile of miRNAs related to oral cancer cell growth inhibition using normal human oral keratinocytes (NHOK) and YD-38 human oral cancer cells. By miRNA microassay analysis, 40 and 31 miRNAs among the 1,769 examined were found to be up- and down-regulated in YD-38 cells compared with NHOK cells, respectively. Using qRT-PCR analysis, the expression levels of miR-30a and miR-1246 were found to be increased in YD-38 cells compared with NHOK cells, whereas miR-203 and miR-125a were observed to be decreased. Importantly, the overexpression of miR-203 and miR-125a significantly inhibited the growth of YD-38 cells. This finding and the microarray data indicate the involvement of specific miRNAs in the development and progression of oral cancer.

The Difference between Clinical and Pathophysiologic Recovery according to Recovery Periods in Experimental Maxillary Sinusitis of Rabbit / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: This study was designed to investigate the difference between clinical and pathophysiologic recovery by comparing the recovery periods in the rabbit sinusitis model. MATERIALS AND METHOD: A synthetic sponge was inserted into the right-side nasal cavities of 15 rabbits. After 2 weeks, the maxillary sinusitis was induced and confirmed by computed tomography (CT) scan. The opacification in CT scan was graded, and the mucosa was harvested from the maxillary sinus. Ciliary beat frequency (CBF) was measured for evaluating mucosal function. Light microscopic, scanning and transmission electron microscopic (SEM & TEM) examinations were performed. Histopathologic findings in microscopic examinations were scored in a semiquantitative measure. Each examination was performed at the time of re-opening of maxillary sinus ostium, 4 weeks and 8 weeks after re-opening of maxillary sinus ostium. RESULTS: The sinus opacification in CT scan and ciliary regeneration in SEM showed significant improvement 8 weeks after re-opening of maxillary sinus ostium. But CBF, tissue inflammation score and ciliary wave disorder were not improved significantly 8 weeks after re-opening of maxillary sinus ostium. CONCLUSION: Clinical, functional and histopathologic recoveries from sinusitis require different periods of time. Incomplete functional and histopathologic recoveries can be the cause of relapse or recurrence of sinusitis. Therefore, close follow-up will be necessary after clinical resolution of sinusitis.

Three Cases of Posterior Inferior Cerebellar Infarction Mimicking Acute Peripheral Vestibulopathy / 대한이비인후과학회지

Vestibular neuritis represents as a spinning type of dizziness accompanied by nausea, vomiting. Central vertigo such as cerebellar infarction may present with nonspecific symptoms similar to those of vestibular neuritis. Basilar artery supplies the cerebellum by branching out into superior cerebellar artery, anterior inferior cerebellar artery, and posterior inferior cerebellar artery. The patient had spinning type of vertigo, nausea, vomiting on the day of visit without any otologic symptoms. Only spontaneous nystagmus was observed. After admission, the patient's dizziness aggravated and emergency brain magnetic resonance imaging was performed. As a result, infarction in the posterior inferior cerebellar artery area was observed. Anticoagulant therapy was performed. Dizziness decreased, the follow-up imaging study showed improvement of the infarction, and the patient was discharged. We experienced three cases of PICA infarction presenting as peripheral types of dizziness, and therefore we are reporting the case.

Photodynamic Therapy(PDT) for Early Glottic Cancer which was Recurred after Initial Treatment Modality / 대한이비인후과학회지

Photodynamic therapy (PDT) is a method used to treat cancer early by irradiating laser with suitable wavelength after injection of a photosensitizer. We introduce the result of PDT for treating an early glottic cancer where initial treatment modality had failed. We tried PDT for 2 patients: one had recurrence after laser cordectomy (T1b) and the other after radiation therapy (T2). Photogem 2 mg/kg was injected intravenously and laser irradiation was performed after 48 hours. We irradiated the lesion site using diode laser (630 nm) delivered through 5 mm cylindrical fiber tip. The energy density, as determined by the depth and site of the lesion, were 138 J/cm and 204 J/cm, respectively. Patient with T1b is alive with no evidence of disease for 46 months post-PDT follow up. Patient with T2 developed chondritis at the subglottis but improved after hyperbaric oxygen therapy and several surgical debridement. After 4 months, tumor recurred at both vocal folds and was managed with total laryngectomy. PDT is a new treatment modality with advantages of good voice quality, short period of admission, and less rate of morbidity and may be another useful salvage option.

ROS Formation and the Mechanism of Photodynamic Therapy Using 9-Hydroxypheophorbide-a on AMC-HN3 Human Head and Neck Carcinoma Cell Line / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: During PDT, photosensitizer accumulates in the cell and irradiation forms ROS. ROS leads to activation of apoptoticpathway and cell death. Elevated intracellular calcium is known to play important role in apoptotic pathway. There are two type of ROS formation. The type of ROS formation differs in type of photosensitizers. We designed the experiment to define the relationship of ROS and cell death in PDT. MATERIALS AND METHOD: AMC-HN3 cells were cultured. Using a CaspACE assay kit, we measured caspases-3 activity after PDT. We also observed intra-cellular calcium concentrations using confocal microscopy (calcium green-1 stain) after PDT. To determine which type of reaction occursduring ROS formation, MTT assay was performed. RESULTS: Confocal microscopy showed that ROS had formed at the site of photosensitizer formation after PDT. After PDT, intracellular calcium increased. MTT assay showed more viability increase in blocking type II reaction. Caspase assay showed highest level after 4hrs. CONCLUSION: ROS is formed at the site photosentizer formation after PDT. Type II reaction was the main type of ROS formation. Apoptosis was main pathway of cell death in low dose of photosensitizer after PDT.