Background Hepatic ischemia-reperfusion injury (IRI) is considered as an effecting factor for hepatocellular carcinoma (HCC) recurrence. Th17/Treg cells are a pair of essential components in adaptive immune response in liver IRI, and forkhead box O1 (FOXO1) has the properties of maintaining the function and phenotype of immune cells. Herein, we illuminated the correlation and function between Th17/Treg cell balance and FOXO1 in IRI-induced HCC recurrence. Methods RNA sequencing was performed on naive CD4+ T cells from normal and IRI model mice to identify relevant transcription factors. Western blotting, qRT-PCR, immunohistochemical staining, and flow cytometry were performed in IRI models to indicate the effect of FOXO1 on the polarization of Th17/Treg cells. Then, transwell assay of HCC cell migration and invasion, clone formation, wound healing assay, and Th17 cells adoptively transfer was utilized to assess the function of Th17 cells in IRI-induced HCC recurrence in vitro and in vivo. Results Owning to the application of RNA sequencing, FOXO1 was screened and assumed to perform a significant function in hepatic IRI. The IRI model demonstrated that up-regulation of FOXO1 alleviated IR stress by attenuating inflammatory stress, maintaining microenvironment homeostasis, and reducing the polarization of Th17 cells. Mechanistically, Th17 cells accelerated IRI-induced HCC recurrence by shaping the hepatic pre-metastasis microenvironment, activating the EMT program, promoting cancer stemness and angiogenesis, while the upregulation of FOXO1 can stabilize the liver microenvironment homeostasis and alleviate the negative effects of Th17 cells. Moreover, the adoptive transfer of Th17 cells in vivo revealed its inducing function in IRI-induced HCC recurrence. Conclusions These results indicated that FOXO1-Th17/Treg axis exerts a crucial role in IRI-mediated immunologic derangement and HCC recurrence, which could be a promising target for reducing the HCC recurrence after hepatectomy.

ObjectiveHepatocellular carcinoma (HCC) is a malignant tumor. The occurrence of HCC is involved in the alteration of a variety of oncogenes or tumor suppressor genes, but the specific molecular mechanism remains unknown. This research proved the effects of long non-coding RNA NEAT1 (lncRNA NEAT1) on the viability, proliferation, migration, and invasion of hepatocellular carcinoma cells and explored the mechanism behind these effects.MethodsNEAT1 in 97H and Huh7 cell lines was overexpressed or knocked down, respectively. The expression of FOXP3 and its target gene PKM2 was hinged on qRT-PCR and Western blot, respectively. RNA pulldown and RNA immunoprecipitation experiments were carried out to detect the interaction between NEAT1 and proteins. Finally, the effect of NEAT1 on the tumor volume of HCC was verified by animal experiments.ResultsA series of experiments have shown that NEAT1 knockdown can inhibit the viability, proliferation, migration, and invasion of HCC cells; NEAT1 can bind FOXP3 to promote PKM2 transcription; PKM2 knockdown can inhibit the viability, proliferation, migration, and invasion of HCC cells; and PKM2 knockdown reversed the function of NEAT1.ConclusionlncRNA NEAT1 can promote the malignant behavior of HCC cells, while silencing of NEAT1 can inhibit that behavior of HCC cells. Mechanically, NEAT1 promotes the transcriptional activation of PKM2 by binding FOXP3, and PKM2 knockout reverses the function of NEAT1.

Background Hepatocellular carcinoma (HCC) is one of the most common malignant tumors with high mortality and poor prognosis. Long non-coding RNAs NEAT1 (lncRNA NEAT1) have been found to play an important role in HCC progression. However, the role and potential molecular mechanism of lncRNA NEAT1 in HCC remain largely unclear. Methods The role of lncRNA NEAT1 both in vitro and in vivo was investigated, with RNA pull-down and RNA immunoprecipitation (RIP) assays being performed to determine the interaction among NEAT1 and FOXO3 and PKM2. In addition, HCC cells were treated with exosomes derived from NEAT1-overexpressing HCC cells, and then cell proliferation, migration and invasion were assessed using in vitro assays. Results In this study, overexpression of NEAT1 promoted the proliferation, migration and invasion of HCC cells, whereas NEAT1 knockdown exhibited the opposite effects. Mechanistically, NEAT1 was found to recruit transcription factor FOXO3 to PKM2 promoter region and upregulate PKM2 expression. Meanwhile, overexpression of NEAT1 increased tumor growth and metastasis in a mouse xenograft model of HCC in vivo via upregulation of PKM2. Furthermore, overexpression of NEAT1 promoted exosome release from HCC cells. Exosomes secreted from NEAT1-overexpressing HCC cells promoted the proliferation, migration and invasion of HCC cells. Conclusion We found that NEAT1 could promote HCC progression via upregulation of PKM2 and exosome-mediated transfer. These data indicated that NEAT1 may be a therapeutic target in HCC.