Inorganic pyrophosphatase 1 activates the phosphatidylinositol 3-kinase/Akt signaling to promote tumorigenicity and stemness properties in colorectal cancer

Abstract

Colorectal cancer (CRC) is a common malignant tumor of the human digestive tract. Inorganic pyrophosphatase 1 (PPA1) plays an imperative role in the advancement of malignant tumors, but its function in CRC is ill-defined. In this study, we inspected the functions of PPA1 in CRC. The abundance of PPA1 in CRC tissues was analyzed by utilizing publicly available data from the The Cancer Genome Atlas and Human Protein Atlas project. Cell counting kit-8 assay and 5-ethynyl-2′-deoxyuridine assay were used to evaluate the viability and proliferation of CRC cells. Bioinformatics analysis was used to forecast the PPA1 related genes and signal pathways in CRC. The protein expression was examined by western blot. The xenograft model was implemented to determine the influence of PPA1 in CRC in vivo. Proliferating cell nuclear antigen, CD133, and CD44 contents in xenograft tumors were evaluated by immunohistochemistry. In the present study, we found that the PPA1 content was heightened in CRC, and the diagnostic value of PPA1 in CRC was enormous. Overexpression of PPA1 enhanced cell proliferation and stemness properties in CRC cells, while downregulation of PPA1 had the opposite effects. PPA1 promoted the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Activation of the PI3K/Akt signaling reversed the effect of PPA1 silencing on cell proliferation and stemness properties in CRC cells. Silencing of PPA1 reduced xenograft tumor growth via modulating the PI3K/Akt signaling pathway in vivo. In conclusion, PPA1 promoted cell proliferation and stemness properties in CRC by activating the PI3K/Akt signaling pathway.