PIN1 Suppresses the Hepatic Differentiation of Pulp Stem Cells via Wnt3a

This study aimed to investigate the role of PIN1 on the hepatic differentiation of human dental pulp stem cells (hDPSCs) and its signaling pathway, as well as the potential therapeutic effects of hDPSC transplantation and PIN1 inhibition on CCl₄ (carbon tetrachloride)-induced liver fibrosis in mice. The in vitro results showed that hepatic differentiation was suppressed by infection with adenovirus-PIN1 and promoted by PIN1 inhibitor juglone via the downregulation of Wnt3a and β-catenin. Compared with treatment with either hDPSC transplantation or juglone alone, the combination of hDPSCs and juglone into CCl₄-injured mice significantly suppressed liver fibrosis and restored serum levels of alanine transaminase, aspartate transaminase, and ammonia. Collectively, the present study shows for the first time that PIN1 inhibition promotes hepatic differentiation of hDPSCs through the Wnt/β-catenin pathway. Furthermore, juglone in combination with hDPSC transplantation effectively treats liver fibrosis, suggesting that hDPSC transplantation with PIN1 inhibition may be a novel therapeutic candidate for the treatment of liver injury.

Expression of PIN1 in Gastrointestinal Stromal Tumours and its Clinical Significance

BACKGROUND

The malignancy of gastrointestinal stromal tumours (GIST) varies greatly. Due to the uncertainty of specific molecular pathogenesis and complexity of biological behaviour of GIST, the aggressiveness and prognosis of GIST cannot be precisely predicted.

MATERIALS AND METHODS

We retrieved 40 paraffin-embedded specimens of surgically resected GIST between January 2013 and May 2015 at the Pathology Department of Yuhuangding Hospital Affiliated to Qingdao University and detected the expression of NIMA-interacting peptidylprolyl isomerase (PIN1) and Ki67, by immunohistochemical methods.

RESULTS

The positivity rate of PIN1 and Ki67 in GIST was 80% and 32.5%, respectively. The expression of PIN1 was associated with risk of malignancy, tumour location, tumour size, and mitotic counts. The expression of Ki67 was also associated with risk of malignancy, tumour location, tumour size, and mitotic counts. The expression of Ki67 was positively related to the expression of PIN1.

CONCLUSION

PIN1 and Ki67 may be potential factors predicting the malignancy of GIST. PIN1 may be an attractive prognostic indicator and therapeutic target for GIST.