The bone marrow stromal compartment in multiple myeloma patients retains capability for osteogenic differentiation in vitro: defining the stromal defect in myeloma.

Defects in bone repair contribute to multiple myeloma (MM) bone disease. It is unknown whether this reflects failure of osteogenic differentiation from mesenchymal stromal cells (MSC), inherent stromal defects or mature cell dysfunction. We quantified the number of fibroblast colony-forming units (CFU-f) and osteoblast colony-forming units (CFU-ob) in freshly isolated bone marrow (BM) from healthy individuals (N = 10) and MM patients (N = 54). CFU-f and CFU-ob were present in MM BM, at comparable frequency to normal subjects, irrespective of disease stage, and the presence of bone disease. Adherent cultures from MM BM are able to differentiate into osteoblasts, as indicated by the early upregulation of RUNX2, SP7, AXIN2 and DLX5, and the production of alkaline phosphatase and calcium. Coculture with MM cells failed to prevent osteogenic differentiation of adult human MSC. On the other hand, MM cells induced cell cycle progression in resting MSC in a cell contact dependent manner. This effect was confirmed using both primary CD138+ cells and MM cell lines, and was not seen with B or T cell lines. Our data confirm the presence of osteoblast progenitors and the preservation of osteogenic function in MM, however dysregulation of cell cycle control may contribute to the loss of normal bone homeostasis that ultimately results in osteolytic bone loss.

APRIL promotes cell-cycle progression in primary multiple myeloma cells: influence of D-type cyclin group and translocation status.

A proliferation-inducing ligand (APRIL) promotes survival and drug resistance in multiple myeloma (MM) cell lines. We studied the effect of APRIL on cell-cycle behavior in primary MM cells and correlated our findings with D-type cyclin expression by immunohistochemistry and/or Western blotting. In MM cases, expressing cyclin D2 APRIL significantly increased the percentage of CD138(+) cells in S + G(2)/M phase (from 8.4% ± 1.9% to 14.3% ± 2.6%, n = 15, P < .01), whereas a lesser effect was seen in cases expressing cyclin D1 (n = 18). Cell-cycle response to APRIL was most marked for cyclin D2-expressing cases with IgH translocations (P < .01) and was accompanied by increased expression of cyclin D2, CDK4, CDK6, and phospho-retinoblastoma protein. Cell-cycle proteins in cyclin D1(+) cells were not modulated by APRIL. Surface expression of B-cell maturation antigen and transmembrane activator and calcium-modulating cyclophilin ligand interactor was not significantly different between cyclin D1(+) and D2(+) MM cells. We observed activation of nuclear factor-κB and PI3-kinase pathways in response to APRIL in both cyclin D1(+) and D2(+) MM cells. In conclusion, APRIL stimulates G(1)/S progression in cyclin D2(+) MM cells bearing IgH translocations but has minimal effect on cyclin D1(+) cells, suggesting MM cells from different cyclin D/translocation classes rely on different mechanisms for cell-cycle re-entry.

Weekly intravenous bortezomib is effective and well tolerated in relapsed/refractory myeloma.

OBJECTIVES: Bortezomib is an effective antimyeloma therapy, but clinical benefits can be limited by neurotoxicity. In newly diagnosed, older patients, modification of the biweekly dosing schedule to weekly regimens improves tolerability whilst maintaining efficacy. There is less information on the efficacy and tolerability of weekly bortezomib regimens in the relapsed/refractory setting. Here, we report our experience of weekly intravenous bortezomib in clinical practice in relapsed/refractory patients. METHODS: We analysed fifty-two patients who received weekly bortezomib for relapsed/refractory MM. RESULTS: Thirty-one per cent of patients received bortezomib beyond first relapse. Almost all (94%) also received steroids and 48% also received an alkylator. The median cumulative dose was 22.6 mg/m(2) , and median length of treatment was 164 d. Three patients reported grade 2 sensory neuropathy, and one reported grade 3 motor neuropathy. There were no grade 4 neurotoxicities. Eighty-three per cent achieved a PR or greater, and the median PFS for the whole group was 13 months. One-year PFS and OS were 53% (95% CI 39-66.6%) and 78% (95% CI 66.7-89.6%), respectively. CONCLUSIONS: Weekly intravenous bortezomib when used in combination with steroids ± alkylator is effective in relapsed/refractory MM, producing outcomes comparable with biweekly regimens and with lower rates of peripheral neuropathy.

Improved response with post-ASCT consolidation by low dose thalidomide, cyclophosphamide and dexamethasone as first line treatment for multiple myeloma.

The use of consolidation or maintenance to improve disease response, and hence clinical outcome, following autologous stem cell transplantation (ASCT) remains the subject of intense clinical research. We carried out a single-arm study to assess the toxicity and efficacy of a short block of consolidation therapy with cyclophosphamide, low dose thalidomide and dexamethasone (CTD) in patients within 6 months following ASCT, as part of frontline therapy for symptomatic multiple myeloma. Forty-five patients who had not progressed were enrolled on the study, and 43 completed treatment on protocol. This regimen was well tolerated soon after ASCT, with only grade 1/2 toxicity apart from neutropenia, and no long-term sequelae. Importantly, CTD consolidation improved the depth of response in treated patients, increasing the complete/very good partial response rate from 44% at 3 months, to 72% at 12 months, which was significantly higher compared with a historical group of control patients (P = 0·002). There was a trend to longer progression-free survival that favoured the study group. Consolidation therapy did not adversely affect subsequent disease response to salvage therapies at relapse. We conclude that CTD consolidation may be a useful, non-toxic and cost-effective strategy to deepen disease response following ASCT, and deserves further study in a randomized trial.

Iron deficiency and iron deficiency anaemia in women.

Iron deficiency (ID) is the most common micronutrient deficiency worldwide with >20% of women experiencing it during their reproductive lives. Hepcidin, a peptide hormone mostly produced by the liver, controls the absorption and regulation of iron. Understanding iron metabolism is pivotal in the successful management of ID and iron deficiency anaemia (IDA) using oral preparations, parenteral iron or blood transfusion. Oral preparations vary in their iron content and can result in gastrointestinal side effects. Parenteral iron is indicated when there are compliance/tolerance issues with oral iron, comorbidities which may affect absorption or ongoing iron losses that exceed absorptive capacity. It may also be the preferred option when rapid iron repletion is required to prevent physiological decompensation or given preoperatively for non-deferrable surgery. As gynaecologists, we focus on managing women's heavy menstrual bleeding (HMB) and assume that primary care clinicians are treating the associated ID/IDA. We now need to take the lead in diagnosing, managing and initiating treatment for ID/IDA and treating HMB simultaneously. This dual management will significantly improve their quality of life. In this chapter we will summarise the importance of iron in cellular functioning, describe how to diagnose ID/IDA and help clinicians choose between the available treatment options.