Telomerase activity in human proliferative breast lesions

Telomerase, a cellular reverse transcriptase, has been detected in the majority of human malignant tumors, where it provides an escape mechanism from proliferative limitations due to progressive telomere erosion with each cell division. In this study, we used a non-radioactive telomeric repeat amplification protocol (TRAP) with an internal telomerase assay standard for the detection and semiquantitative analysis of 98 single frozen sections of normal breast tissue and benign and malignant breast lesions on an automated laser-fluorescence sequencer. Telomerase activity was detected in 36 of 40 (90%) infiltrating breast carcinomas, whereas no activity was found in nonmalignant breast tissues including blunt duct adenosis, papilloma, ductal hyperplasia and atypical ductal hyperplasia. However, telomerase activity was detected in 59% of ductal in situ carcinomas, suggesting that telomerase reactivation is an early event in breast carcinogenesis. We found a positive correlation between telomerase activity levels and cell proliferation determined by MIB1 immunostaining. No correlation, however, could be demonstrated between telomerase activity and other known breast cancer prognostic indicators. Telomerase activity was also detected in 60% of fibroadenomas indicating that careful interpretation of analysis of telomerase activity in fine needle aspirates is required, since low telomerase activity may not necessarily be an indicator of malignancy in breast tissue.

Osteomyelitis due to Cryptococcus neoformans in advanced age. Case report and review of literature

In an 84-year-old man cryptococcosis with a pronounced osteomyelitic course (involvement of a rib, two thoracic vertebrae, the sacrum and a femur) was diagnosed histologically post mortem, thus directing attention to cryptococcosis in advanced age. The presumptive chronic course of the Cryptococcus neoformans (Cr. n.) infection in this patient was ascribed to chronic kidney failure, diabetes mellitus and chronic obstructive lung disease. Special reference is made to the mycological and radiological diagnosis of cryptococcosis of the bones as well as to its pathogenesis, therapy and epidemiology.