Figure 2. Greater matrix stiffness increased glioma stemness by inducing BCL9L. (A) Western blotting analysis of BCL9L expression in tissues derived from the HS and LS groups. (B) Western blotting analysis of BCL9L expression in LN229 cells cultured on gels of different stiffness levels. (C) Flow cytometry analysis of CD133 expression in LN229 cells treated with negative control shRNA (LN229-NC), BCL9L shRNA #1 (LN229-KO1) or BCL9L shRNA #2 (LN229-KO2) and cultured on 16-kPa stiffness gels, and in LN229 cells treated with the control vector (LN229-Vec) or BCL9L overexpression vector (LN229-BCL9LOE) and cultured on flask dishes. (D) The proliferation of LN229-NC, LN229-KO1, LN229-KO2, LN229-Vec or LN229-BCL9LOE cells pre-cultured on 16-kPa stiffness gels, and of LN229-Vec or LN229-BCL9LOE cells cultured on flask dishes. (E) Tumor volumes were measured at various time points in mice injected with LN229-NC, LN229-KO1 or LN229-KO2 cells pre-cultured on 16-kPa stiffness gels, and in mice injected with LN229-Vec or LN229-BCL9LOE cells cultured on flask dishes. (F) The cell colonies formed by LN229-NC, LN229-KO1 or LN229-KO2 cells pre-cultured on 16-kPa stiffness gels and by LN229-Vec or LN229-BCL9LOE cells cultured on flask dishes were detected at various time points. (G) Tumorigenesis of mice subcutaneously injected with 104 LN229-NC, LN229-KO1 or LN229-KO2 cells pre-cultured on 16-kPa stiffness gels, or injected with LN229-Vec or LN229-BCL9LOE cells cultured on flask dishes. *P < 0.05, **P < 0.01, n.s. no significant difference.