BCR and B-cell non-Hodgkin lymphoma: Anti-CD20 monoclonal antibodies are part of many therapeutic regimens for the treatment of B-cell NHL, however, there is data suggesting that BCR pathway inhibitors such as BTK, SYK and PI3K kinase inhibitors may impair the efficacy of anti-CD20 monoclonal antibodies via down-regulation of cell surface levels of CD20 and impairment of antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity (87).