Multiple Myeloma: A potential treatment for an incurable blood cancer

Researchers at a Swedish University have identified a protein which could revolutionise the prognosis for multiple myeloma, an incurable and terminal blood cancer.

Multiple myeloma typically becomes apparent during an individual’s early 60s and is believed to account for 1% of total malignancies worldwide. It is characterised by abnormal proliferation of plasma cells – a form of white blood cell responsible for the synthesis and secretion of antibody. Defective plasma cells secrete non-functional “paraprotein” antibodies (which can cause severe kidney damage) in addition to invading bone marrow. Invasion of the latter may give rise to anaemia, fatigue and bone fractures. There is no cure for multiple myeloma, although a range of drugs – including novel targeted therapies – may be used to buy patients more time. Fewer than 50% of patients with multiple myeloma will live for five years following diagnosis.

The group, based at Lund University, systematically analysed the effects of various monoclonal antibodies – supplied from a “BioLibrary” by a local Swedish company – on tumour cell growth. Monoclonal antibodies were first developed in the 1980s in Cambridge and have since been allocated an important niche in clinical and experimental medicine. They can target receptors, transmitters and structural proteins to influence cell signalling, growth and proliferation.

The researchers noted that BI-505, a monoclonal antibody which targets the cell-adhesion molecule ICAM-1, significantly reduced the growth of tumour cells injected into immunodeficient mice. It was also shown to significantly increase survival time. Further experiments demonstrated that these effects were mediated by macrophages, a subset of white blood cells which engulf and digest tumour cells.

BI-505 is now undergoing tests in 15 Swedish patients recently diagnosed with multiple myeloma. Whilst the results in mice have proved promising, it remains to be seen if this success will be translated to clinical medicine.