ABCB1 and lymphoma: Nevertheless, lymphoma is a disease that often displays several mechanisms that favor chemotherapy resistance; therefore, clinical signs recur, such as the mutation of the MDR1 gene, which modifies the physiology of the P glycoprotein, thus hindering the action of chemotherapy molecules, especially the class of antitumor antibiotics, such as doxorubicin, the main component of the CHOP protocol [49].