Adhesion to bone marrow stroma inhibits apoptosis of chronic lymphocytic leukemia cells.
B-cell chronic lymphocytic leukemia (B-CLL) is characterized by the accumulation of monoclonal long-lived B cells which are apparently resistant to normal apoptotic regulation. Since bone marrow stromal cells play an essential role in B lymphopoiesis, we have investigated whether stromal cells influence B-CLL cell survival. Our results indicate that intimate contact with stromal cells reduces B-CLL cell apoptosis and prevents the loss of bcl-2 protein expression. Binding of B-CLL cells to stromal cells requires simultaneous action of beta1 and beta2 integrins. The interaction between B-CLL cells and other cell types seems important for their survival and may represent an important mechanism underlying accumulation of malignant cells in B-CLL patients.
Lagneaux
L
L
Service de Médecine Interne et Laboratoire d'investigation Clinique Henri Tagnon, Institut J. Bordet, Brussels, Belgium. alain_delforge@ulb.ac.be
Delforge
A
A
De Bruyn
C
C
Bernier
M
M
Bron
D
D
D017209:Apoptosis / Q000502:physiology*; D001402:B-Lymphocytes / Q000473:pathology*; D018821:CD18 Antigens / Q000502:physiology; D002448:Cell Adhesion; D002450:Cell Communication; D002470:Cell Survival; D015973:Gene Expression Regulation, Leukemic; D019254:Genes, bcl-2; D006801:Humans; D019012:Integrin beta1 / Q000502:physiology; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000473:pathology*; D009363:Neoplasm Proteins / Q000502:physiology*; D014411:Neoplastic Stem Cells / Q000166:cytology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017154:Stromal Cells / Q000166:cytology*
D018821:CD18 Antigens; D019012:Integrin beta1; D009363:Neoplasm Proteins; D019253:Proto-Oncogene Proteins c-bcl-2