LHPP suppresses colorectal cancer cell migration and invasion in vitro and in vivo by inhibiting Smad3 phosphorylation in the TGF-β pathway

Bin Hou; Wenhan Li; Peng Xia; Fengyu Zhao; Zhao Liu; Qingnuo Zeng; Shilong Wang; Dongmin Chang

doi:10.1038/s41420-021-00657-z

LHPP suppresses colorectal cancer cell migration and invasion in vitro and in vivo by inhibiting Smad3 phosphorylation in the TGF-β pathway

Cell Death Discov. 2021 Oct 4;7(1):273. doi: 10.1038/s41420-021-00657-z.

Authors

Bin Hou^#¹, Wenhan Li^#², Peng Xia³, Fengyu Zhao³, Zhao Liu³, Qingnuo Zeng³, Shilong Wang³, Dongmin Chang⁴

Affiliations

¹ Department of Thoracic Surgery, Shaanxi Provincial People's Hospital, 256W, Youyi Road, Xi'an, 710068, Shaanxi, China.
² Department of Surgical Oncology, Shaanxi Provincial People's Hospital, 256W, Youyi Road, Xi'an, 710068, Shaanxi, China.
³ Department of Surgical Oncology, the First Affiliated Hospital of Xi'an Jiaotong University, 277W, Yanta Road, Xi'an, 710061, Shaanxi, China.
⁴ Department of Surgical Oncology, the First Affiliated Hospital of Xi'an Jiaotong University, 277W, Yanta Road, Xi'an, 710061, Shaanxi, China. dr_changdm@sina.com.

^# Contributed equally.

Abstract

The roles of phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) in tumorigenesis have been recently proven in hepatocellular carcinoma (HCC), cervical, pancreatic, bladder, and thyroid cancers. Previous research demonstrated that LHPP repressed cell proliferation and growth by inactivating the phosphatidylinositol 3-kinase/AKT signaling pathway in vitro and in vivo. However, the functions and potential mechanisms of LHPP as a tumor suppressor in colorectal cancer (CRC) metastasis are still unknown. Consequently, the Transwell assay and xenograft nude model showed that LHPP inhibited migration and invasion of CRC cells in vitro and in vivo, respectively. The expression of total and nuclear epithelial-to-mesenchymal transition (EMT)-related proteins were significantly reduced after LHPP upregulation. Human Gene Expression Array and IPA (Ingenuity Pathway Analysis) commercial software were applied to identify differentially expressed genes (DEGs) and potential cell signaling pathways. A total of 330 different genes were observed, including 177 upregulated genes and 153 downregulated genes. Bioinformatics analysis suggested that the transforming growth factor-β (TGF-β) signaling pathway was highly inactivated in this study. Then, Smad3 phosphorylation was apparently decreased, whereas Smad7 expression was markedly enhanced after upregulating LHPP expression. These results were proven once again after TGF-β1 stimulation. Furthermore, a specific inhibitor of Smad3 phosphorylation (SIS3) was applied to verify that LHPP repressed EMT of cancer cells by attenuating TGF-β/Smad signaling. The results suggested that suppression of the TGF-β/Smad signaling pathway by LHPP overexpression could be abolished by SIS3.