IL-16 production is a mechanism of resistance to BTK inhibitors and R-CHOP in lymphomas

Here, we investigated non-genetic mechanisms of ibrutinib resistance in marginal zone lymphoma (MZL) and their broader therapeutic implications. Chronic ibrutinib exposure generated a resistant MZL model that showed cross-resistance to BTK inhibitors and degraders, without evidence of multidrug resistance or genetic alterations.

Integrated transcriptomic, epigenetic, and proteomic analyses revealed extensive reprogramming, including activation of PI3K/AKT, MAPK, and MYC pathways, repression of apoptosis and oxidative phosphorylation, and a prominent cytokine-secretory phenotype. Interleukin-16 (IL-16) emerged as a central mediator of resistance. IL-16 was transcriptionally upregulated, actively secreted, and sufficient to induce ibrutinib resistance across multiple CD9-positive models of MZL, mantle cell lymphoma, chronic lymphocytic leukemia (CLL), and activated B-cell-like diffuse large B-cell lymphoma.