Figure 10. Effect of SPARC on UC cell proliferation in in vitro and in vivo tumorigenicity.

(A) Western blots showing the expression of SPARC protein in 20 μg protein of UMUC3 (top panel), T24, and T24T (bottom panel) human bladder cancer cell lines after overexpression and/or depletion of SPARC. The effect of genetic manipulation of SPARC on UC cell proliferation was determined by CyQuant assay. UMUC3, T24, and T24T transfected with full-length SPARC in pcDNA3.1 (pSP) and pcDNA3.1 empty vector control (VC) or transduced with lentiviral vector laden with short hairpin targeting Sparc gene (shSP) and its irrelevant nontarget control (NTsh). Representative growth curves of cell proliferation measured at 24, 48, and 72 hours performed twice in quadruplicate. *P < 0.05, comparing cells overexpressing SPARC (pSP) with their matching VC; **P < 0.05, comparing cells depleted of SPARC with their matching NTsh, Student’s t test. (B) Western blot of cycle regulatory proteins cyclins A, D, and E and their inhibitors p21 and p27 in 20 μg of the aforementioned cell lines. Equal protein loading was confirmed by reprobing blots with tubulin. (C) Scatter plots representing s.c. tumor take and volume of the UMUC3 T24, and T24T genetically manipulated for SPARC expression after injection in nude mice. *P < 0.05, χ² test; **P < 0.05, 2-tailed Student’s t test.