Figure 7. SPARCL1 expression is associated with mature vessels.

(A) Expression of SPARCL1 (green) and CD31 (red) was detected by immunofluorescence costaining in normal colon, and GBP-1^hi and GBP-1^lo CRC (n = 9 each). The combined isotype antibodies were used for the control staining. Tissues were counterstained with DRAQ5 (Cell Signaling Technology; blue). Colocalization is indicated by arrows. CD31 expression only is indicated by an arrowhead. Scale bar: 25 μm. Vessel perimeters and areas were quantitatively determined for all the stained vessels (n = 270; 10 vessels/patient) and are depicted as dot plots (red bars indicate the mean values and SD). (B) The vessel perimeters and areas as quantified in A in relation to vessels with high and low SPARCL1 expression for all tissues. (C) Immunofluorescence costaining of SPARCL1 (green), CD31 (red), and α-SMA (blue). Scale bar: 25 μm. α-SMA–positive mural cell coverage was categorized as negative/weak, moderate, or high for 296 vessels from 30 patients, and the relative size of each category is given for SPARCL1^hi and SPARCL1^lo vessels. The relative amount of coverage is depicted for vessels with SPARCL1 expression in ECs only (n = 205). The relative number of vessels with different alpha-SMA coverage (%) is indicated by different gray tones. (A and B) Representative experiment of 2 independent experiments is depicted. *P < 0.05 and ***P < 0.001, by ANOVA, with Levene and Games-Howell (unequal variance) tests (A), Student’s t test (B), and χ² test (C).