Early tumor-cell gene expression changes may predict the response to first-line bortezomib-based therapy in patients with newly diagnosed multiple myeloma.

PURPOSE: Maximizing the response rate to first-line therapy in patients with multiple myeloma (MM) is important because it leads to improved outcome. Gene-expression studies have identified prognostic gene sets in patients receiving bortezomib-based therapy. Comparison of the lists of genes derived from two gene-expression-based models (GEP70, GEP80) showed that they overlap in three genes, namely PSMD4, BIRC5, and KIAA1754. An unanswered question is whether early gene-expression changes can be used as predictors of the response to first-line bortezomib. In this study we aimed to examine the predictive value of gene expression changes for the depth of response after bortezomib-based therapy in newly diagnosed MM. METHODS: We prospectively assessed the relation between early PSMD4, BIRC5, and KIAA1754 gene expression changes (before therapy and one week later) and the response rate after bortezomib-based therapy in 25 patients with newly diagnosed MM. Gene expression was studied by RT-PCR on CD138-selected plasma cells, and changes were recorded as upregulation, downregulation, or unchanged. RESULTS: Whereas baseline prognostic factors including genetic lesions and stage were not predictive of the response rate, we found that early BIRC5 and KIAA1754 gene-expression changes were significantly associated with the depth of response to bortezomib (p=0.001 and p<0.001, respectively). PSMD4 was not predictive of the depth of response. KIAA1754 upregulation was linked to complete remission (CR) or very good partial remission (VGPR). BIRC5 upregulation was linked to stable disease (SD) or progressive disease (PD). We also observed that BIRC5 upregulation was associated with worse progression-free survival (PFS). CONCLUSIONS: Our results suggest that BIRC5 and KIAA1754 gene-expression changes may predict the response to bortezomib-based therapy. These data may have relevance for the stratification and early adaptation of first-line treatment in patients with newly diagnosed MM.

Ex Vivo Induction of Multiple Myeloma-specific Immune Responses by Monocyte-derived Dendritic Cells Following Stimulation by Whole-tumor Antigen of Autologous Myeloma Cells.

The introduction of novel agents has significantly expanded treatment options for multiple myeloma (MM), albeit long-term disease control cannot be achieved in the majority of patients. Vaccination with MM antigen-loaded dendritic cells (DCs) represents an alternative strategy that is currently being explored. The aim of this study was to assess the immunogenic potential of ex vivo-generated monocyte-derived DCs (moDCs), following stimulation with the whole-antigen array of autologous myeloma cells (AMC). MoDCs were loaded with antigens of myeloma cells by 2 different methods: phagocytosis of apoptotic bodies from γ-irradiated AMC, or transfection with AMC total RNA by square-wave electroporation. Twenty patients with MM were enrolled in the study. Following stimulation and maturation, moDCs were tested for their capacity to induce T-helper 1 and cytotoxic T lymphocyte responses in vitro. Both strategies were effective in the induction of myeloma-specific cytotoxic T lymphocyte and T-helper 1 cells, as demonstrated by cytotoxicity and ELISpot assays. On the whole, T-cell responses were observed in 18 cases by either method of DC pulsing. We conclude that both whole-tumor antigen approaches are efficient in priming autologous antimyeloma T-cell responses and warrant further study aiming at the development of individualized DC vaccines for MM patients.

Intestinal pseudo-obstruction associated with amyloidosis.

Intestinal pseudo-obstruction is a condition characterised by clinical manifestations of mechanical obstruction of the intestine in the absence of any organic occlusion of the lumen. This syndrome has rarely been reported to complicate the course of systemic amyloidosis. We describe the case of a 64-year-old man who presented with the syndrome of small bowel pseudo-obstruction secondary to AL amyloid infiltration of the gastrointestinal tract. We comment on the pathophysiology and on the clinical importance of amyloidosis-associated intestinal pseudo-obstruction.