Apoptotic and necrotic effects of tumour necrosis factor-alpha potentiated with hyperthermia on L929 and tumour necrosis factor-alpha-resistant L929.

PURPOSE: The cytotoxic effect of the combination treatment of TNF-alpha and hyperthermia on L929 and TNF-alpha-resistant L929 (rL929) cells was investigated. MATERIALS AND METHODS: L929 cells were treated with TNF-alpha (5 ng/mL), heating at 43 degrees C or the combination of TNF-alpha and heating. The cells were harvested at different time within the 24-hour period. The viability and the type of cell death of the harvested cells were examined. RESULTS: When L929 cells were treated with a combination of TNF-alpha and heating the cells died quickly and apoptosis increased to an overwhelming extent, especially in the group pre-treated with TNF-alpha for 1 h prior to heating. Although rL929 cells were resistant to TNF-alpha alone, the cells became sensitive to TNF-alpha treatment when combined with heating. Similar to the L929 cell, the cells also died rapidly and exhibited apoptosis to a higher extent. Using an Annexin-V-FITC kit and flow cytometer, we found that both necrosis and apoptosis occurred. Agarose gel electrophoresis of DNA extracted from treated cells showed that the DNA fragments were multiples of approximately 200 bp. Furthermore, by studying the kinetics of cell death and apoptosis, we found that the loss of cell membrane integrity preceded the DNA fragmentation in both L929 and rL929 cells. CONCLUSION: The results suggested that hyperthermia may enhance the necrotic and apoptotic effects of TNF-alpha on some tumour cells and overcome the resistance of some tumour cells to TNF-alpha.

Inflammatory pseudotumors of the central nervous system.

Inflammatory pseudotumor is a disease with unsettled pathogenesis. The brain is a rare site of occurrence. The aim of this study is to investigate ALK-1 protein expression and IgG4-positive plasma cells detection in 4 intracranial inflammatory pseudotumors. Three dural-based and 1 intraventricular inflammatory pseudotumors were retrieved from the hospitals' archive. The data on clinical presentation, radiological findings, procedure undertaken, and patients' progress were collected. Sections from the excised lesions were examined under hematoxylin and eosin, histochemical, and immunohistochemical staining including ALK-1 and IgG4. All 4 cases displayed typical histological features of inflammatory pseudotumor with dense lymphoplasmacytic infiltrate admixed with small number of benign-looking spindle cells in a collagenous stroma. Three cases exhibited high density of IgG4-positive plasma cells per high-power field. ALK-1 was negative. ALK expression was not found in any of our cases. On the contrary, the detection of significant number of IgG4-positive plasma cells in 3 inflammatory pseudotumors suggests that a considerable proportion of intracranial inflammatory pseudotumor may belong to the IgG4-related subgroup. Hence, a trial of corticosteroid after histological confirmation may be valid to avoid unnecessary risk-taking neurosurgical procedures or in cases with incomplete tumor removal.

A 33-year-old Chinese woman with a left frontal tumor.

Rhabdoid tumor cells are typically observed in atypical teratoid/rhabdoid tumor (AT/RT) but may also be seen in meningioma,glioma, melanoma, rhabdomyosarcoma and metastatic carcinoma.We present an astroblastoma with unusual rhabdoid features which is rarely described in the English literature. Apart from the rhabdoid tumor cells, all the histopathological features typical for astroblastoma are present in this case. These features include pseudopapillary arrangement, astroblastic pseudorosettes, perivascular hyalinization and calcifications, absence of fibrillary background and a pushing tumor border. The tumor cells display a multilineage immunohistochemical profile. In addition, diffuse and strong membranous and cytoplasmic dot-like pattern is appreciated with epithelial membrane antigen (EMA). The diagnosis of astroblastoma is also well supported by the age of presentation, anatomical location and radiological features of the tumor.We believe that on top of the above-mentioned unusual tumors with rhabdoid cells, astroblastoma should also be considered in the list of differential diagnosis.

Vulvar basal cell carcinoma in China: a 13-year review.

OBJECTIVE: We conducted a 12-year retrospective review of vulvar basal cell carcinoma (BCC) in a Chinese population. STUDY DESIGN: Medical records and histopathologic reports were examined from 5 major Hospitals in Hong Kong to list all patients diagnosed with vulvar BCC. Clinical data and histologic materials were reviewed. RESULTS: Sixteen vulvar BCCs were diagnosed. Most of them were pigmented. They were removed by simple excision or wide local excision. All the carcinomas were identified in the reticular dermis. The predominant histologic pattern was nodular, which may be mistaken as adenoid cystic carcinoma. CONCLUSION: The high proportion of pigmented vulvar BCCs suggested that biopsy should be performed for any pigmented lesion in a Chinese patient. The BCCs are superficial and tissue-preserving treatment approach is recommended. The tumor depth estimation is difficult and intraoperative frozen section consultation may be helpful. Formal histopathologic assessment should be used to reach an objective diagnosis.

Fine needle aspiration cytology in follicular dendritic cell sarcoma: a report of two cases.

BACKGROUND: Since the first description of extranodalfollicular dendritic cell sarcoma in 1994, there has been a gradual increase in understanding of the morphologic features and clinical presentation of this tumor. However, difficulties persist in making cytologic diagnosis. CASES: Two cases of follicular dendritic cell sarcoma with fine needle aspiration cytology (FNAC) findings were reported. The first patient was a Chinese woman who presented with a right tonsillar mass, which was followed by right submandibular recurrence. The second patient was a Chinese man with known history of Castleman's disease of the nasopharynx complicated by follicular dendritic cell sarcoma, followed by tumor recurrence in cervical lymph nodes. FNAC of both recurrent cases showed isolated or syncytial sheets of tumor cells containing eosinophilic granular cytoplasm, ill-defined cell borders, round to oval nuclei, solitary round eosinophilic nucleoli and fine chromatin. CONCLUSION: The tumor cells in follicular dendritic cell sarcoma show cytologic features reminiscent of native follicular dendritic cells but with a greater than expected cell number and nuclear pleomorphism. These cells may be immunohistochemically inert for follicular dendritic cell markers CD21 and CD35. A presumptive diagnosis on the basis of cytologic examination is possible when paying attention to the subtle morphologic features.

Focal segmental glomerulosclerosis after membranous glomerulonephritis in remission: temporal diversity of glomerulopathy after bone marrow transplantation.

Heavy proteinuria after bone marrow transplantation (BMT) is rare. Pathology shows membranous glomerulonephritis (MGN) in most cases. After BMT, focal segmental glomerulosclerosis (FSGS) after resolution of MGN has not been reported. We describe a 13-year-old boy who had matched unrelated donor allogeneic BMT for relapsed acute lymphoblastic leukemia, complicated by chronic graft-versus-host disease. Nephrotic syndrome developed 1 year after BMT and renal biopsy revealed MGN. Immunosuppressive therapy achieved good clinical remission, and treatment was stopped after 15 months. He developed significant proteinuria 55 months later. The second renal biopsy showed FSGS without changes of MGN. This distinctive disease evolution gives inspiring implications. Complete morphological resolution of graft-versus-host disease-associated MGN, achieved in our case, has not been previously documented. Recurrent significant proteinuria after BMT is not necessarily due to previous renal lesion, and a repeat renal biopsy is indicated. The pathogenesis of MGN and FSGS are different, and different mechanisms of glomerular injury can interplay in a single patient after BMT. This case helps to expand our knowledge of the temporal morphological spectrum of renal lesions associated with BMT.