Expression pattern of CCN family genes during chondrogenesis. hBMSCs were cultured in a micromass culture system in chondrogenic induction medium for up to 21 days. Total RNA was collected at 1, 3, 7, 14, and 21 days, and the mRNA expression levels of CCN1 to CCN6 (A–F) and COL2A1 (G) were evaluated by real time RT-PCR. The expression of each gene was normalized to that of S29 ribosomal RNA. Data are reported as mean ± SD (n = 3). *p < 0.05, **p < 0.01, ***p < 0.001 versus day 1 (one-way ANOVA/Tukey). Results are representative data of at least three independent experiments.