Figure 2. AURKB inhibition enhances osimertinib-induced apoptosis through BIM and PUMA induction.

(A) H1975 was treated with osi at the indicated concentrations ± PF03814735 (PF, 2 μM). EC50 was assessed by CellTiter-Glo assays at 72 h (mean ± s.d., n=3).

(B) H1975 was treated with osi (1 μM) and/or PF (2 μM). Colonies were stained with crystal violet after 14 days.

(C) A schematic demonstrating the crosstalk between the EGFR signal transduction pathway and BCL-2 family-regulated apoptosis.

(D) H1975 treated with the indicated agents was assessed by immunoblots.

(E) qRT-PCR for BIM and PUMA mRNA in H1975 treated with the indicated agents (2 μM) for 24 h. Data were normalized against β-Actin (mean ± s.d., n=3). **, P<0.01; ns, not significant (Student’s t-test).

(F) H1975, transfected with the indicated siRNAs, was treated with the indicated agents (2 μM) for 48 h. Cell death was quantified by AV staining (mean ± s.d., n=3). **, P<0.01 (Student’s t-test).

(G) H1975, transfected with the indicated siRNAs, was treated with the indicated agents (2 μM) for 24 h and assessed by immunoblots.

(H-I) H1975, transfected with the indicated siRNAs, was treated with osi (2 μM) and assessed by immunoblots at 24 h. Cell death was quantified by AV staining at 48 h (mean ± s.d., n=3). **, P<0.01; ***, P<0.001 (Student’s t-test).

(J) Comparison of PUMA mRNA, BIM mRNA, and BIM protein expression in tumors from EGFR-mutant lung adenocarcinoma (LUAD) patients with a good or poor prognosis in TCGA (n=22). *, P<0.05 (Student’s t-test).

(K) Kaplan-Meier analysis of overall survival in EGFR-mutant LUAD patients from TCGA based on the expression of BIM protein and PUMA mRNA. Blu, high BIM protein or PUMA mRNA (n = 13); Red, low BIM protein or PUMA mRNA (n = 6). P = 0.009 (Log-rank test).

See also Figure S2.