We also found a significant positive correlation of the mRNA expression levels of collagen‐related molecules in primary liver cancers with the stiffness‐related transcription co‐activator YAP1, suggesting that changes in extracellular collagen content or ECM stiffness could affect the activity of YAP1 and subsequently influence transcriptional activity in primary liver cancer cells. This evidence concerns the gene YAP1 and liver cancer.