SMAD3 and hepatocellular carcinoma: Besides, our previous study demonstrated a lower expression of linc00261 in cytoplasm compared to nucleus in liver cancer cell lines [23], which supports the current phenomenon that reduced linc00261, especially cytoplasmic linc00261, allows SMAD3 to get phosphorylation (Ser423/425), and escape from ubiquitination and degradation, thereby translocate into the nucleus, and ultimately promote the progression of HCC.