Solitary lymphomatoid granulomatosis at the maxilla

Lymphomatoid granulomatosis (LYG) is an uncommon Epstein-Barr virus (EBV)-associated B-cell lymphoproliferative disorder distinct from lymphoma. LYG primarily occurs in the lung with or without accompanied lesions in the skin, central nervous system, kidney, gastrointestinal tract, nose, eyes, liver and oral cavity. Solitary extrapulmonary LYG is extremely rare, and whether solitary lesions progress onto pulmonary development and dysfunction is controversial. Herein, we report a case on a solitary LYG in the maxilla gingiva with bone exposure in a patient who had been taking methotrexate for rheumatoid arthritis.ope

Gingival Juvenile Xanthogranuloma

Juvenile xanthogranuloma (JXG) is a benign histiocytosis that occurs in the pediatric population. Cutaneous JXG is the most common form, while extracutaneous lesions, including oral JXG, is extremely rare. Cutaneous JXG can occur as multiple lesions and may have systemic visceral involvement, but this is not seen in oral JXG. In this case, we report a solitary oral JXG at the gingiva in a 3-year old male.ope

The Axin2-snail axis promotes bone invasion by activating cancer-associated fibroblasts in oral squamous cell carcinoma

Background: In bone-invasive oral squamous cell carcinoma (OSCC), cancer-associated fibroblasts (CAFs) infiltrate into bony tissue ahead of OSCC cells. In the present study, we aimed to investigate the role of the Axin2-Snail axis in the biological behaviour of CAFs and bone invasion in OSCC. Methods: The clinicopathological significance of Axin2 and Snail expression was investigated by immunohistochemistry in an OSCC cohort containing 217 tissue samples from patients with long-term follow-up. The influence of the Axin2-Snail axis on the biological behaviour of OSCC cells and CAFs was further investigated both in vitro and in vivo. Results: Axin2 expression was significantly associated with Snail expression, the desmoplasia status, and bone invasion in patients with OSCC. In multivariate analysis, lymph node metastasis, desmoplasia, Axin2 expression, and Snail expression were independent poor prognostic factors in our cohort. Consistent with these findings, OSCC cells demonstrated attenuated oncogenic activity as well as decreased expression of Snail and various cytokines after Axin2 knockdown in vitro. Among the related cytokines, C-C motif chemokine ligand 5 (CCL5) and interleukin 8 (IL8) demonstrated a strong influence on the biological behaviour of CAFs in vitro. Moreover, both the desmoplastic reaction and osteolytic lesions in the calvaria were predominantly decreased after Axin2 knockdown in OSCC cells in vivo using a BALB/c athymic nude mouse xenograft model. Conclusions: Oncogenic activities of the Axin2-Snail axis are not limited to the cancer cells themselves but rather extend to CAFs via regulation of the cytokine-mediated cancer-stromal interaction, with further implications for bone invasion as well as a poor prognosis in OSCC.ope

Frequent BRAF V600E mutation in keratocystic odontogenic tumor

Dept. of Dentistry/박사Keratocystic odontogenic tumor (KCOT) is a benign intraosseous odontogenic epithelial tumor in the jaw, characterized as an odontogenic cyst, odontogenic keratocyst, in the past. In 2005, the World Health Association working group reclassified the cyst as a benign tumor for several clinical and molecular genetic reasons. Clinically, KCOT shows aggressive growth patterns and high recurrence rates which is relatively similar to odontogenic tumors rather than odontogenic cysts. Molecular genetic features present in KCOT support its neoplastic behavior as well, such as proliferative markers and tumor suppressor gene mutations/loss of heterozygosity. Although PTCH gene mutation was considered to be critical in KCOT pathogenesis due to its close association in syndrome related lesions, there are needs in identifying other oncogenic mutations, especially in sporadic KCOT. BRAF V600E mutation has been identified in odontogenic tumors, representatively ameloblastoma. It is an oncogenic driver mutation which activates the mitogen-activated protein kinase (MAPK) pathway and has commercial target inhibitors, such as vemurafenib and dabrafenib. In this study, frequent BRAF V600E mutation was identified in KCOT by gene sequencing. The results are as follows. 1. BRAF V600E mutations were identified for the first time in 63.2% of KCOT and 28.6% of OOC by sanger sequencing in formalin fixed paraffin embedded tissue samples with/without microdissection. 2. There was no statistically significant difference between KCOT mutation status and clinical information such as age, sex, location, recurrence and multiple lesions. 3. The gold standard to identify BRAF V600E mutation in KCOT is gene sequencing rather than immunohistochemistry. 4. Microdissection is useful in validating mutations in cystic tumors or inflamed lesions. The results support KCOT as a tumor and relates its pathogenesis to BRAF V600E mutation and the MAPK pathway. BRAF target inhibitors are expected to be an effective and non-invasive future therapeutics for KCOT in the future. 각화낭성치성종양은 악골의 양성 골내 치성 상피 종양으로 과거 치성각화낭이라는 명칭의 치성낭으로 분류되었다. 세계보건기구는 2005년에 각화낭성치성종양을 낭에서 종양으로 재정의를 하였다. 임상적으로 각화낭성치성종양은 공격적인 성장 양상과 상대적으로 높은 재발율을 보이는데, 이는 치성낭보다 치성종양의 특성에 가깝다. 분자유전학적인 관점에서도 종양의 특성을 보이는데, 증식 관련 표지자와 종양억제유전자변이/이형접합성상실 등이 그 예이다. 이중 PTCH 유전자 변이가 가장 중요하게 여겨졌으나 기저세포모반증후군과 관련된 병소와 달리 산발적으로 발생하는 병소에서는 낮은 변이 비율 등 근거가 상대적으로 뚜렷하지 않아 다른 종양성 유전자 변이를 발견할 필요성이 있다. 최근에 BRAF V600E 유전자 변이는 법랑모세포종을 비롯한 치성종양에서 발견이 되었다. 이는 종양 유발 유전자변이로 mitogen-activated protein kinase (MAPK) 경로를 활성화하며 베무라페닙과 다브라페닙과 같은 상용화된 억제제 약물이 있다. 이 연구에서는 각화낭성치성종양에서 높은 빈도로 BRAF V600E 유전자 변이가 발생한다는 것을 유전자 시퀀싱을 통해 관찰하였다. 연구 결과는 다음과 같다. 1. 포르말린 고정 조직에 유전자 시퀀싱을 하여 최초로 63.2%의 각화낭성치성종양과 28.6%의 진성각화치성낭에서 BRAF V600E 유전자 변이를 관찰되었다. 2. 각화낭성치성종양의 BRAF 유전자 변이 여부와 임상적 양상 (연령, 성별, 발병 위치, 재발 여부 및 다발성 병소 여부 등)은 통계학적으로 유의한 연관성을 보이지 않았다. 3. 각화낭성치성종양에서 BRAF V600E를 확인하기에 가장 적합한 방법은 면역조직화학염색보다 유전자 시퀀싱이다. 4. 낭성 종양 또는 염증이 심한 조직에서는 현미해부를 통해 유전자 변이 여부를 더 정확하게 확인 할 수 있다. 이러한 연구 결과들은 각화낭성치성종양이 종양임을 다시 한번 확인 시켜주며 BRAF V600E 유전자 변이 및 MAPK 경로와 연관된 병인을 가지고 있음을 보여준다. 이는 각화낭성치성종양의 치료로 표적 억제제를 이용한 비침습적 치료의 가능성을 제시하여 준다.ope

Biobanking of Oral-Derived Bioresources

Oral-derived bioresources(ODBs) for human-derived material research have been mainly sampled by individual researchers. Difficulties in ODB secure has impeded advances in dental research and associated industries. ODBs have been obtained in a few biobanks within general hospitals, yet the amount of oral-derived specimens is relatively low compared to other organs and lacked practical clinical data. Recently, biobanks of dental hospitals have started systematic management in South Korea, thus these biobanks are expected to invigorate high-quality ODB banking in the field. In this review, we will discuss the collection and utilization of OBDs, such as teeth, dental plaque, gingival crevicular fluid and saliva, and the need of dental hospital-based biobanks.ope

The role of pathology in the light of Georges Canguilhem

The philosophy of medicine by Georges Canguilhem, who wrote The Normal and the Pathological, defined pathology as the study that precedes physiology and deals with another norm of life. The debate behind the con tinuous reclassification of odontogenic keratocyst(OKC) is appropriate example for Canguilhem’s definition. In this paper, we will examine medical and dental cases important at the clinic, especially OKC, and discuss its hidden meanings with a Canguilhem’s point of view.ope

Analysis of the Difference in the Importance of Instructors and Clinical Dental Hygienists for Oral Pathology Learning Objectives

Background: The purpose of this study was to identify the differences in the importance of oral pathology learning objectives for instructors and clinical dental hygienists and provide basic data that can guide learning objectives for acquiring practically necessary basic knowledge in the clinical field. Methods: Through the first-stage expert meeting, 27 items with less than four points out of 129 learning objectives in 15 detailed areas were deleted, 12 additional opinions were reflected, 114 learning objectives were set, and a survey was conducted with 253 people. Results: There were statistically significant differences in 92 items after examining the difference between professors and clinical dental hygienists. Among the areas of inflammation and repair, “Can explain the five symptoms of inflammation” had the highest with a score at 4.76 in the case of the professors. Among the areas of tooth damage, “Can explain abrasion” had the highest with a score at 4.61 in the case of the clinical dental hygienists. Conclusion: I would like to propose the existing 15 detail areas and 129 learning objectives as 14 detail areas and 98 learning objectives and strengthen the job competency of dental hygienists in the future. First, you need to develop competencies that are highly relevant to your work. Second, it is necessary to develop related textbooks and educational materials based on revised learning objectives and competencies. Third, based on revised learning objectives, the dental hygienist national examination should be improved. Through these changes in education, the education of oral and maxillofacial disease subjects should strengthen job competencies among dental hygienists with learning objectives that can be applied to actual clinical practice based on basic knowledge rather than knowledge orientation. In addition, it is possible to improve the quality of dental hygiene studies.ope

Histopathologic examination in the primary dental clinic

Biopsy is a critical method for disease diagnosis and treatment planning. It can be applied from simple inflammatory lesions to malignant tumors. But many general dental practitioners are unfamiliar with the basic knowledge and skills required for biopsy. Moreover, biopsy indications and contraindications for certain diseases may differ depending on the type of dental practice environment and the specialty of the dentist. Biopsy education can increase the choices a dentist has during disease diagnosis. Here we will discuss details on biopsy needed to the general dentist.ope

A Proposal to Prevent the "Mephisto Sign" Side Effect of Botulinum Toxin Type A Injection in Chronic Migraine

Botulinum toxin type A (BoNT-A) has been reported as an effective treatment for chronic migraine. When BoNT-A is injected on the frontalis muscle for chronic migraine, an unexpected clinical side effect called the "Mephisto sign" may occur. The aim of this article is to propose a method to eliminate or prevent the Mephisto sign side effect. A 25-year-old female patient visited the hospital and was diagnosed with chronic migraine. A total of 155 U of BoNT-A was injected into 31 sites. 2-weeks later, and the patient developed the Mephisto sign. An additional 2-U dose was administered bilaterally to the lateral-most point of the frontalis muscles, and the eyebrow morphology returned to normal within 2-3 weeks. We propose that the development of the Mephisto sign may be prevented with an additional BoNT-A injection of 2-4 U bilaterally to the lateral most point of the frontalis muscles during the primary injection process.ope

The Pathogenic Effect of Cortactin Tyrosine Phosphorylation in Cutaneous Squamous Cell Carcinoma

BACKGROUND/AIM: Cortactin (CTTN) has been considered a promising molecular prognostic factor in various types of cancers. In this study, we aimed to investigate the role of CTTN in the pathogenesis of cutaneous squamous cell carcinoma (CSCC). MATERIALS AND METHODS: CTTN and phospho-CTTN (p-CTTN) expression was determined in 10 healthy controls and 38 CSCC tissue samples by immunohistochemistry. The influence of CTTN on the biological behavior of CSCC cells was also investigated. RESULTS: p-CTTN expression was significantly increased in CSCC than control samples. In contrast, no significant difference in CTTN expression was found between control and CSCC tissues. Moreover, a significant association was found between recurrence-free survival with p-CTTN expression, but not with CTTN expression. Furthermore, the proliferative, migratory, and invasive abilities of CSCC cells were significantly decreased by CTTN-siRNA transfection. CONCLUSION: CTTN phosphorylation is strongly associated with CSCC pathogenesis and may serve as a molecular biomarker of CSCC.ope