Induction of Apoptosis in Head and Neck Cancer Cells by Dominant Negative C-myb Gene Therapy / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Although the role of c-myb in head and neck tumor has not been studied, aberrant expression of c-myb in various cancer has been demonstrated recently, suggesting that c-myb may play a role in tumorigenesis. Consequently, disrupting c-myb function might prove a possible stratergy for controlling cancer cell growth. The purpose of this study is to investigate the possibility of clinical application of adenovirus-mediated dominant negative c-myb (DN-myb) gene therapy in head and neck cancer. MATERIALS AND METHOD: All tissues were obtained from patients undergoing therapeutic operation for head and neck tumors and were assayed the expression of c-myb and bcl-2 in tumor and normal tissue by RT-PCR. We have generated a replication-deficient recombinant adenovirus encoding the dominant negative c-myb (Ad/DN-myb) or control adenovirus encoding no transgene (Ad/GFP) and infected adenovirus to SNU-1076, head and neck tumor cell line. We examined cell proliferation by 3H-thymidine assay, apoptosis by DNA fragmentation, bcl-2 expression and Akt/PKB phosphorylation by Western immunoblot, and IGF-II, VEGF mRNA expression by RT-PCR. RESULTS: c-myb expression of head and neck tumor tissues was significantly higher than that of normal tissue, indicating that these genes may play an important role in carcinogenesis of head and neck tumor. Ad/DN-myb infected SNU-1076 cells decreased cell proliferation, IGF-1I and VEGF expression, and remarkably increased their apoptosis through the down-regulation of bcl-2 expression and the inhibition of Akt/PKB pathway activation. CONCLUSION: Results obtains from these study suggest that DN-myb induced apoptosis of head and neck tumor cells and the adenovirusmediated DN-myb gene therapy may be a potential molecular therapy for the treatment of head and neck tumor.

A Case of Teratoma of the Middle Ear / 대한이비인후과학회지

Teratomas are true tumours derived from the three germinal layers (ectoderm, mesoderm, endoderm) which differentiate into identifiable tissues and organs. Embryologically, they are thought to result from the displacement of pluripotent cells from normal tissue during embryogenesis. Teratomas commonly occur in the sacrococcygeal region, gonads and mediastinum, but teratoma of the middle ear is exceedingly rare. Treatment for teratomas of the middle ear should be early, complete surgical excision to prevent local destruction and although rare, malignant transformation. We present a case of middle ear teratoma with a review of the literature.

A Case of Non-recurrent Laryngeal Nerve / 대한이비인후과학회지

A non-recurrent laryngeal nerve is rarely encountered condition, and its anomalous path makes it more vulnerable to injury during thyroid surgery and compression by a thyroid mass. This anomaly appears as a consequence of an aberrant subclavian artery, which arises from an anomaly in the primitive forth aortic arch. So, the surgeon must always be aware of the possibility of a nonrecurrent laryngeal nerve. Pre-operative recognition of this nerve allows surgeons to avoid the nerve injury. In some cases, surgeons are able to predict the presence of this nerve pre-operatively by way of clinical symptoms, chest X-ray or barium swallow. We experienced a case of right nonrecurrent laryngeal nerve during a total thyroidectomy in a 47-year-old female, and report with literature review.

Primary Cholesteatoma Originating in the Posterior Fossa / 대한이비인후과학회지

Primary cholesteatomas(epidermoids) originating in the posterior fossa are rare lesions that grow to a large size through slow accumulation of desquamated epithelium. These lesions grow between and ultimately displace cranial nerves, vascular structures, and the brainstem, causing a long course of progressive neurological deficits. Primary cholesteatomas are diagnosed with computed tomography and magnetic resonance imaging. The treatment of choice is surgical excision but portions of the capsule adherent to vital structures should be left undisturbed. Several approaches or combinations of approaches have been utilized to reach the lesions of the ventral brainstem. Among these, the petrosal approach has many advantages. We have experienced a huge primary cholesteatoma of the posterior fossa, so we report with review of literatures.