Related Experiment Videos
Bone marrow of patients with active multiple myeloma: angiogenesis and plasma cell adhesion molecules LFA-1, VLA-4,
A Vacca1, M Di Loreto, D Ribatti
1Department of Biomedical Sciences and Human Oncology, University of Bari Medical School, Italy.
Abstract:
Bone marrow plasma cells and stromal cells in multiple myeloma (MM) have been shown to be capable of releasing cytokines with angiogenic properties. Plasma cells can also express adhesion molecules controlling their adhesive interactions with endothelial cells. In the present study, we have evaluated by immunohistochemistry the extent of angiogenesis in the bone marrow of: a) 51 patients with active and non-active MM; b) 25 patients with monoclonal gammopathy of undetermined significance (MGUS). Plasma cells were investigated by flow cytometry for the expression of the adhesion molecules LFA-1, VLA-4, LAM-1, and CD44. The results showed that, while angiogenesis was very low or absent in patients with MGUS and non-active MM, it increased markedly in those with active MM. The highest detectability of plasma cell adhesion molecules, except LAM-1, was also found in these patients. The functional significance of these findings is unknown. Their consistent occurrence in the bone marrow of active myeloma patients, however, strongly suggests that more frequent adhesive interactions between plasma cells and their microvasculature underlie tumor dissemination.
Insights
Active multiple myeloma (MM) correlates with increased bone marrow angiogenesis and plasma cell adhesion molecule expression. These factors may drive tumor spread in patients with active MM.
Area of Science:
- Oncology
- Hematology
- Cell Biology
Background:
- Multiple myeloma (MM) involves plasma cells and stromal cells in the bone marrow.
- These cells can release cytokines that promote angiogenesis.
- Plasma cells express adhesion molecules that mediate interactions with endothelial cells.
Purpose of the Study:
- To evaluate the extent of angiogenesis in the bone marrow of patients with active MM, non-active MM, and monoclonal gammopathy of undetermined significance (MGUS).
- To investigate the expression of adhesion molecules (LFA-1, VLA-4, LAM-1, CD44) on plasma cells in these patient groups.
Main Methods:
- Immunohistochemistry was used to assess angiogenesis in bone marrow samples.
- Flow cytometry was employed to analyze plasma cell adhesion molecule expression.
- Patient groups included 51 MM patients (active and non-active) and 25 MGUS patients.
Main Results:
- Angiogenesis was significantly increased in active MM patients compared to MGUS and non-active MM patients, where it was minimal or absent.
- Higher expression of adhesion molecules LFA-1, VLA-4, and CD44 was observed on plasma cells from active MM patients.
- LAM-1 expression did not follow the same pattern as other adhesion molecules.
Conclusions:
- Increased angiogenesis and plasma cell adhesion molecule expression are characteristic of active multiple myeloma.
- These findings suggest that enhanced interactions between plasma cells and the bone marrow microvasculature may contribute to tumor dissemination in active MM.