Targeting of Cytotoxic Conjugates to Kaposi's Sarcoma-Derived Cells

We assayed the cytotoxicity of conjugates in which the plant toxin saporin (SAP) was linked to human basic fibroblast growth factor (bFGF) and urokinase-type plasminogen activator (uPA). Both bFGF and uPA play an important role in angiogenesis, and their cell surface receptors are expressed at high levels in cancer cells. The conjugates were tested on a Kaposi's sarcoma-derived cell line, IST-KS2, as a model of an actively proliferating component of Kaposi's sarcoma lesions which are highly vascularized. Both bFGF and uPA were very effective at targeting saporin to KS cells, leading to cell killing even at low concentrations of the conjugates. The bFGF-SAP and uPA-SAP mitotoxins were also highly toxic toward the permanent, endothelium-derived EAhy926 cell line. EAhy926 cells were very sensitive to two immunotoxins containing an anti-endothelium monoclonal antibody coupled to saporin or ricin A chain, whereas IST-KS2 cells were not affected by these conjugates, in agreement with immuno cytochemical observations.     

Meningeal leukemia complicating prolymphocytoid transformation of B-chronic lymphocytic leukemia

A patient who developed a meningeal leukemia during prolymphocytoid transformation of B-chronic lymphocytic leukemia is described. The central nervous system (CNS) complication occurred after 5 years of relatively benign course. Almost all CNS mononuclear cells showed the typical morphology and immunology of prolymphocytic leukemia cells, whereas a mixture of prolymphocytoid elements and small-sized lymphoid cells was observed in peripheral blood. In this case the more aggressive component was present at diagnosis and showed an uncommonly slow progression allowing the occurrence of the CNS involvement.     

Pneumothorax: appearance on lateral chest radiographs

The appearance of pneumothorax on lateral radiographs obtained with the patient erect were reviewed in 100 patients (122 total examinations). A pneumothorax could be seen on the lateral projection in 89% of the examinations (109 of 122). The displaced pleural line was most frequently identified anteriorly or posteriorly and was less commonly identified at the lung apex or in a subpulmonic location. In 11 cases, an air-fluid level was the only recognizable finding of a pneumothorax on the lateral projection. Although in 27% of examinations (32 of 122) the pneumothorax was either not seen (11%) (n = 13) or was a subtle finding (16%) (n = 19), in 14% of examinations (17 of 122) the lateral projection provided helpful information to supplement the posteroanterior projection.