SOX11-PAX5-CD19 axis correlates with BTKi resistance in MCL. (A) Violin plot showing the relative expression levels of SOX11, PAX5, and CD19 in normal, BTKi-S, and BTKi-R MCL cell samples from the patients. Each dot represents an individual tumor B cell, with colors indicating clinical outcomes. (B) Scatter plot illustrates the correlation between SOX11 and PAX5 (left) and PAX5 and CD19 (right) in BTKi-S and BTKi-R MCL tumor B cells, respectively. A fitted line with 95% confidence intervals is shown. The correlation coefficient and P value are indicated on each plot. (C) SOX11, PAX5, and CD19 mRNA expression are positive correlates in patients’ tumor cells (n = 39, ECOG 1405 data sheets). (D) Immunoblot analysis showing the expression of SOX11, PAX5, and CD19 in primary cells from IBN-sensitive and IBN-resistant patients. β-Actin was used as a loading and transfer control. (E) Increased levels of PAX5 were observed in CD5⁺, CD19⁺, and CD23^– (B1a) PB mononuclear cells from Tg-SOX11 mice (n = 6) in comparison to WT mice (n = 5) controls. ∗∗, P < .001. ECOG, Eastern Cooperative Oncology Group.