Overview of the BCR pathway with highlighted mechanisms of BTKi resistance. *Location of known BTKi resistance mutation. ↑ Protein is upregulated as a mechanism of BTKi resistance. ↓ Protein is upregulated as a mechanism of BTKi resistance. BCL10, B-cell leukemia/lymphoma 10; BLNK, B-cell linker protein; CDK, cyclin dependent kinase; ERK 1/2, extracellular signal-regulated kinase 1/2; MALT1, mucosa-associated lymphoid tissue lymphoma translocation protein 1; PKC, protein kinase C; RB1, retinoblastoma 1; SMARCA, SWI/SNF related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member; SYK, spleen tyrosine kinase; XPO1, exportin-1.