The Role and Underlying Mechanism of Exosomal CA1 in Chemotherapy Resistance in Diffuse Large B Cell Lymphoma

Chemotherapy resistance plays a major role in treatment failure of diffuse large B cell lymphoma (DLBCL). Exosomes are closely related to tumor drug resistance. Herein, the expression of exosomal proteins in DLBCL and their roles in chemotherapy resistance of DLBCL are explored. Tandem mass tag labeling proteomics was used to perform proteomic profiling in exosomes from DLBCL patients’ serum. The expression of carbonic anhydrase 1 (CA1) in parental, chemo-resistant DLBCL cells and DLBCL patient exosomes was detected. Proliferation of DLBCL following CA1 knockdown was investigated both in vitro and in vivo, along with the effects on nuclear factor κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) pathways. We identified 54 differentially expressed proteins. We validated that the expression level of exosomal CA1 was higher in chemo-resistant DLBCL cells than in chemo-sensitive counterparts. Knockdown of CA1 inhibited the growth of DLBCL via inhibiting the activation of NF-κB and STAT3 signaling pathways both in vitro and in vivo. An increased expression level of exosomal CA1 was associated with poorer prognosis, and exosomal CA1 could be used as a biomarker to predict chemotherapeutic efficacy. Our study suggests that exosomal CA1 can promote chemotherapy resistance in DLBCL via the NF-κB and STAT3 pathways, and it can serve as a biomarker for DLBCL prognosis.