Cancer specific Mucin-1 glycoforms are expressed on multiple myeloma.

Present therapies cannot cure the large majority of patients with multiple myeloma (MM) and therefore new treatment strategies are imperative. This study analysed the different glycosylation profiles of Mucin-1 (MUC1) on MM and acute myeloid leukaemia (AML) cells using a series of anti-MUC1 antibodies. Seventy-three per cent of the MM patients had plasma cells that expressed the fully glycosylated forms of MUC1. In contrast to controls, normal bone marrow cells and AML cells, the differentiation-dependent and cancer-associated glycoforms of MUC1 were present on 59% and 36% MM tumour cells respectively. This indicated that aberrantly glycosylated MUC1 is a potential immunotherapeutic target in MM patients.

Mucin-1 is expressed on dendritic cells, both in vitro and in vivo.

Dendritic cells (DCs) are the best professional antigen-presenting cells to stimulate cytotoxic as well as T helper cells and are therefore appropriate candidates for establishing immunotherapy. The concept of our vaccination program is to introduce the tumor-associated antigen mucin-1 (MUC1) into DCs. Analysis of immature and mature DCs--before transducing the antigen MUC1--already demonstrated expression of MUC1 on in vitro monocyte-derived DCs upon maturation. Different culture methods as well as maturation cocktails showed similar results concerning the upregulation of MUC1 expression. Furthermore, we studied the expression of MUC1 on DCs in vivo. No MUC1 expression was found on blood DCs, or on thymic or tonsil DCs. On the other hand, synovial fluid from patients with arthritis contained DCs that were found to express MUC1. This study shows for the first time that the tumor-associated antigen MUC1 is expressed on in vivo DCs. We further show that MUC1 is also expressed on in vitro cultured bone marrow-derived DCs of human MUC1 transgenic mice, supporting the relevance of this mouse model to the human situation. The observation that MUC1 is present on in vivo DCs suggests a functional role, but this physiological function remains to be elucidated.

Aspirin inhibits Chlamydia pneumoniae-induced nuclear factor-kappa B activation, cytokine expression, and bacterial development in human endothelial cells.

OBJECTIVE: Chlamydia pneumoniae has been associated with atherosclerosis. Infection of vascular endothelial cells with C pneumoniae increases the expression of proatherogenic cytokines mediated by nuclear factor (NF)-kappaB, a transcription factor. The present study was designed to test the effect of aspirin on C pneumoniae-induced NF-kappaB activation, interleukin expression, and bacterial development in cultured human endothelial cells. METHODS AND RESULTS: Aspirin, its metabolite salicylic acid, and 2 other unrelated NF-kappaB inhibitors showed a strong concentration-dependent inhibitory effect on chlamydial growth, indicated by the reduction of bacterial inclusions and the titer of infectious progeny. Involvement of the transcription factor NF-kappaB was confirmed by electrophoretic mobility shift assay and by transfection experiments with appropriate decoy oligodeoxynucleotides. Attenuation of the C pneumoniae-induced activation of NF-kappaB by aspirin also reduced the secretion of interleukin-6 and interleukin-8, indicating efficient inhibition of NF-kappaB gene expression. Reduction of chlamydial growth was not caused by apoptosis of the host cell, as determined by monitoring characteristic chromatin condensation. CONCLUSIONS: These data provide evidence that NF-kappaB-mediated gene activation represents a crucial step in the developmental cycle of C pneumoniae. Aspirin exerts an anti-chlamydial effect that is due to the inhibition of C pneumoniae-induced NF-kappaB activation, which might account for some of the cardioprotective activity of aspirin.