Pathway-Focused Analysis of Liver Regeneration

To search the factors associated with liver regeneration, a pathway-focused array analysis was performed. Briefly, total RNA was isolated from half of the freshly collected liver tissues from each mouse by using an RNeasy Mini Kit (Qiagen). We used 1 mg of total RNA from each sample and pooled all of the 4 RNA samples at the same time point in each group to generate cDNA using the RT2 First Strand Kit (SABiosciences). A mouse extracellular matrix and adhesion molecule PCR array and a cytokine and chemokine PCR array, each containing a total of 84 genes, were used according to the manufacturer’s instructions (SABiosciences)28 (link)29 (link)30 (link). All of the data were normalized to the expression of housekeeping genes, and the expression level for each gene was quantified based on the cycle threshold (Ct). Data analysis was performed with a web-based analysis program (SABiosciences, http://pcrdataanalysis.sabiosciences.com/pcr/arrayanalysis.php). We selected the genes that were up- and down-regulated by more than 1.5-fold for further categorization analysis according to their biological function.