Drug resistance in non-hodgkin lymphomas

PI3K/AKT/mTOR signaling pathway plays a crucial role in cell proliferation, survival, differentiation, motility and intracellular transport. PI3Kδ, an isoform of PI3K, is highly expressed in B lymphocytes and is involved in the malignant progression of B-cell lymphoma. Thus, PI3Kδ has emerged as an attractive target for the development of anti-B-cell lymphoma drugs. Currently, there are several PI3Kδ inhibitors approved by the FDA for the treatment of B-cell lymphoma, each with its own characteristics, but also with varying degrees of adverse effects in clinical practice. Due to the complexity and diversity of the pathogenesis of B-cell lymphoma, single-target PI3Kδ inhibitors often have limited efficacy and are prone to drug resistance, and need to be combined with chemotherapy or other targeted drugs to enhance their efficacy. The future trend is to design novel inhibitors with higher efficacy and lower toxicity or to develop novel combination regimens with other chemotherapy, radiotherapy, and target drugs to acquire better anti-tumor effects with reduced adverse effects. This review summarizes the PI3Kδ inhibitors that have been approved for the treatment of B-cell lymphoma or are still in clinical trials, mainly focusing on their characteristics, adverse effects and combination regimens.