Significance of Notch Expression in Acute Myeloid Leukemia

BACKGROUND: Notch is a gene family encoding receptors to transduce intercellular signals involved in cell-fate determination. Although several lines of evidence indicate that abnormal Notch signaling may contribute to neoplastic transformation, little is known regarding the role of Notch in the pathogenesis of leukemia. METHODS: To explore the functional significance of Notch1 in acute myeloid leukemia (AML), the expression of Notch1 and its association with survivin and p27Kip1 expression was examined in 50 patients with de novo AML. RESULTS: Notch1 transcripts were expressed in 40 (80%) cases with a variable degree of expression, and the fraction of AML cells in the G0/G1 phase was higher in Notch1-positive cases than in Notch1-negative cases. Survivin was shown to be present in 38 (76.0%) cases, and Notch1 expression highly correlated with survivin mRNA expression (r=0.7170, P<0.001). p27Kip1 was present in 40 (80.0%) cases of AML and p27Kip1 expression was significantly associated with Notch1 expression (r=0.8770, P<0.001). Except for one case, the simultaneous expression of survivin and p27Kip1 was not seen in all cases that were negative for Notch1 expression. There were no differences in clinical outcomes according to Notch1 expression. CONCLUSION: Notch1 expression was a frequent event and has functional significance in the alteration of the cell cycle in AML cells. Notch1 expression was also significantly associated with survivin and p27kip1 expression in AML cells. To evaluate the clinical significanceand functional role of Notch1 expression in the aberrant regulation of survivin and p27Kip1 expression in de novo AML, a further study with a larger number of patients is necessary.

A Case Report of Posttransplant Lymphoproliferative Disorders Successfully Treated with R-CHOP in Korea

Posttransplant lymphoproliferative disorder (PTLD) is a group of heterogeneous lymphoid diseases that cause serious complications after organ or stem cell transplantation. The onset of PTLD is mostly due to EBV infection-induced B-cell proliferation and a defect in cytotoxic T cell function that occurs with immunosuppression. The usual treatment strategy for PTLD is reduction or withdrawal of immunosuppressive drugs with or without the administration of antiviral agents. Recently, various studies on the efficacy of rituximab or chemotherapy have been reported. We report two cases of rapidly progressing and complicated PTLDs after kidney transplantation that were successfully treated with a combination regimen consisting of rituximab, cyclophosphamide, adriamycin, vincristine and prednisolone (R-CHOP).

A Case of Successful Management of Sarcoidosis with Chylothorax Using Octreotide / 결핵및호흡기질환

Sarcoidosis is a multi-system granulomatous disorder of an unknown etiology and affects individuals worldwide. It is characterized pathologically by the presence of non-caseating granulomas in more than one involved organ. However, pleural involvement of sarcoidosis is rare and there are no reported cases in Korea. Traditionally, sarcoidosis has often been treated with systemic corticosteroids or cytotoxic agents. In particular, chylothorax with sarcoidosis is usually treated with corticosteroid for approximately 3~6 months, followed by repeated therapeutic thoracentesis, talc pleurodesis, dietary treatment, or thoracic duct ligation where needed. We encountered a 46 years old female patient presenting with cough, dyspnea and both hilar lymphadenopathy (stage I) on chest radiograph. The patient was diagnosed with a non-caseating granuloma, sarcoidosis by a mediastinoscopic biopsy. For one month, she had suffered from dyspnea due to right side pleural effusion, which was clearly identified as a chylothorax on thoracentesis. Corticosteroid therapy with dietary adjustment was ineffective. She was treated successfully with a subcutaneous injection of octreotide for 3 weeks and oral corticosteroid. We report a case of successful and rapid treatment of chylothorax associated with sarcoidosis using octreotide and oral corticosteroid.

A Case of Concurrent Thymic Carcinoma with Systemic Lupus Erythematosus / 결핵및호흡기질환

A thymic carcinoma is a rare malignant neoplasm of the thymus epithelium, which can be distinguished from a benign or invasive thymoma. Contrary to a thymoma, the association of a thymic carcinoma and autoimmune disease is rare, with only a few cases having been reported. Herein, a case of thymic carcinoma diagnosed concurrently with systemic lupus erythematosus (SLE) is reported. A 49 year-old man presented at our clinic with myalgia. He was diagnosed with SLE, based on an oral ulcer, lymphopenia, and positive ANA and anti-Sm antibodies. Incidentally, a routine chest X-ray showed a large mediastinal mass. Pathological examination of the mediastinal mass revealed an undifferentiated thymic carcinoma, of WHO classification type C. Further work-up for staging showed multiple bone and lung metastases. With a palliative aim, he received systemic chemotherapy, but refused further chemotherapy after the 2nd course. Currently, the patient has not been followed up since the chemotherapy.