Peripheral neuropathy in patients with multiple myeloma: molecular effects of bortezomib

Multiple myeloma (MM) is a B cell neoplasm characterized by uncontrolled growth of malignant plasma cells within the bone marrow . The introduction of new treatment regimens and medicinal substances, particularly proteasome inhibitors (e.g. bortezomib or carfilzomib) and immunomodulatory drugs (e.g. lenalidomide, pomalidomide, and monoclonal antibodies), have radically changed MM therapy by improving the response rate and progression-free survival. However, these potentially effective drugs are associated with a number of side effects, the most serious of which include peripheral neuropathy, which appears in 40% of MM patients with bortezomib treatment and up to 70% with thalidomide treatment during long-term exposure. Usually, symptoms of neuropathy disappear after drug discontinuation or dose reduction. However, as a result, the effectiveness of the treatment is lowered and survival time is reduced. The pathogenesis of chemotherapy-induced peripheral neuropathy  is not fully understood. Current research focuses on areas such as the change in the expression of genes responsible for the proper functioning of the nervous system, neuroprotective protein factors, oxidative stress, pro-inflammatory factors and epigenetic changes (miRNA, DNA methylation or histone acetylation). Thoroughly elucidating the mechanisms responsible for the development of chemotherapy-induced peripheral neuropathy will allow us to reduce/eliminate this side effect and improve quality of life for patients.