Figure 7.

Human breast cancer cells decrease decorin expression in human stromal fibroblasts via a paracrine effect. Young and ionizing radiation (IR)-induced senescent human breast stromal fibroblasts were serum starved for 24 h and then incubated with media conditioned by the designated human breast cancer cell lines (MCF-7, SKBR3, ZR-75-1, MDA-MB-231 and MDA-MB-468) for another 24 h. RNA was extracted and decorin expression was assessed by real-time PCR after first-strand cDNA synthesis. Relative decorin mRNA levels to the respective untreated control with glyceraldehyde-3-phosphate dehydrogenase (GAPDH) serving as the reference gene are presented as means ± standard deviations of five independent experiments. Statistically significant differences from the respective untreated control are depicted by asterisks (*) (Student’s t test, p < 0.05).