Variation of nicotinic subtype 7 and muscarinic subtype M3 acetylcholine receptor expression in three main types of leukemia

Cholinergic receptors, such as 7-nicotinic acetylcholine receptor (7-nAChR) and M3-muscarinic acetylcholine receptor (M3-mAChR), have been demonstrated to serve a significant role in the proliferation, differentiation and apoptosis of leukemic cells. However, the expression of these receptors in samples from patients with leukemia remains unclear. The present study aimed to determine the expression of M3-mAChR and 7-nAChR in the bone marrow or peripheral blood of 51 patients with leukemia, including acute myeloid leukemia (AML; n=33), acute lymphoblastic leukemia (ALL; n=13), and chronic myeloid leukemia (CML; n=5). Peripheral blood mononuclear cells (PBMCs) were also isolated from healthy subjects (n=5) for comparison. Western blot analysis was performed to determine the protein expression profiles, and a pattern of decreased 7-nAChR levels in patients with leukemia was observed. Among the leukemia types, the lowest expression of 7-nAChR and M3-mAChR were identified in patients with T-cell ALL/lymphoma (T-ALL). CML exhibited the highest level of M3-mAChR, which was significantly different from APL and AML-M4, yet not from healthy subjects (P<0.05). Therefore, different expression profiles of 7-nACR and M3-mAChR were detected amongst the leukemia types. Collectively, the present study supports the potential role of cholinergic signaling in mediating leukemogenesis. However, further studies in larger cohorts are required to validate these findings.