BCL2L1 and mantle cell lymphoma: Mechanistic studies have found that knockdown of SMARCA4 in MCL cells leads to deletion of the transcriptional repressor of the BCL2L1 gene, which transcriptionally upregulates the BCL2L1 gene and increases the BCL2L1 protein, resulting in significant resistance to the combination of ibrutinib and vinotec in MCL cells (71).