SPARC alters the sensitivity of MIP101 colorectal cancer cells to chemotherapy. (A) TUNEL assay shows the effect of exogenous SPARC on apoptosis in MIP/5FU cells. (B) Levels of SPARC secreted by MIP/SP cells (clones c1, c2, and c3) compared with control MIP/Zeo cells and following concentration of the incubation media (conc, c2-conc). (C) Colony-forming assay of MIP/SP and control MIP/Zeo cell lines following exposure to incremental concentrations of 5-FU, CPT-11, or ETO. (D) Sensitivity of MIP/SP compared with MIP/Zeo cells to chemotherapy (FACS analysis of annexin V–labeled cells). *P < 0.05, Student’s t test; n = 3 different experiments. (E) Immunoblots of MIP/Zeo and MIP/SP cells exposed to 500 μM 5-FU for 12 hours and probed for caspase-3 and α-fodrin.