Runqiu Jiang

Interleukin-22 promotes human hepatocellular carcinoma by activation of STAT3†‡§

Interleukin‐22 (IL‐22), one of the cytokines secreted by T helper 17 (Th17) cells, was recently reported to be a novel inflammation driver through STAT3 signaling activation. We aimed to investigate the role of IL‐22 expression in hepatocellular carcinoma (HCC). We demonstrated significant up‐regulation of IL‐22 in human HCC tumor infiltrated leukocytes (TILs) compared to peripheral lymphocytes. Moreover, IL‐22 expression was significantly higher in Edmondson Grade III‐IV HCC patients versus Grade I‐II, confirmed by both real‐time polymerase chain reaction and immunohistochemistry. Both IL‐22 receptor α and IL‐23 were highly expressed in HCC and adjacent cirrhotic tissues compared to normal controls. Enhanced tumor growth and metastasis was found in mice that underwent subrenal transplantation of MHCC‐97H cells cotransplanted with IL‐22+ TILs cells. STAT3 phosphorylation and up‐regulation of downstream genes Bcl‐2, Bcl‐XL, CyclinD1, and vascular endothelial growth factor (VEGF) promoted tumor growth and metastasis. In vitro studies confirmed the tumor‐promoting and antiapoptotic effect of IL‐22, as well as IL‐6. In the mouse chronic hepatitis and HCC model, sustained and increased IL‐22 expression and STAT3 activation were found in liver tissues. A linear correlation was demonstrated between IL‐22 expression and hepatic complementary proliferation. An in vivo diethyl‐nitrosamine‐induced mouse HCC model verified that tumor formation was significantly decreased in IL‐22 knockout mice. Conclusion: Excessive IL‐22 can be found in the HCC microenvironment, leading to tumor growth, inhibition of apoptosis, and promotion of metastasis due to STAT3 activation. (HEPATOLOGY 2011;)

IL-17A Plays a Critical Role in the Pathogenesis of Liver Fibrosis through Hepatic Stellate Cell Activation

Liver fibrosis is a severe, life-threatening clinical condition resulting from nonresolving hepatitis of different origins. IL-17A is critical in inflammation, but its relation to liver fibrosis remains elusive. We find increased IL-17A expression in fibrotic livers from HBV-infected patients undergoing partial hepatectomy because of cirrhosis-related early-stage hepatocellular carcinoma in comparison with control nonfibrotic livers from uninfected patients with hepatic hemangioma. In fibrotic livers, IL-17A immunoreactivity localizes to the inflammatory infiltrate. In experimental carbon tetrachloride–induced liver fibrosis of IL-17RA–deficient mice, we observe reduced neutrophil influx, proinflammatory cytokines, hepatocellular necrosis, inflammation, and fibrosis as compared with control C57BL/6 mice. IL-17A is produced by neutrophils and T lymphocytes expressing the Th17 lineage–specific transcription factor Retinoic acid receptor–related orphan receptor γt. Furthermore, hepatic stellate cells (HSCs) isolated from naive C57BL/6 mice respond to IL-17A with increased IL-6, α-smooth muscle actin, collagen, and TGF-β mRNA expression, suggesting an IL-17A–driven fibrotic process. Pharmacologic ERK1/2 or p38 inhibition significantly attenuated IL-17A–induced HSC activation and collagen expression. In conclusion, IL-17A+ Retinoic acid receptor–related orphan receptor γt+ neutrophils and T cells are recruited into the injured liver driving a chronic, fibrotic hepatitis. IL-17A–dependent HSC activation may be critical for liver fibrosis. Thus, blockade of IL-17A could potentially benefit patients with chronic hepatitis and liver fibrosis.

IL-22 is related to development of human colon cancer by activation of STAT3

BackgroundIt has been previously reported that IL-22, one of the cytokines secreted by Th17 cells, demonstrates both a protective and inflammatory promotion effect in inflammatory bowel disease (IBD) through STAT3 signaling activation. We sought to investigate the role of IL-22 expression in colon cancer (CC).MethodsThe expression of IL-22 and related molecules were detected in human CC, the detail function and mechanism of IL-22 were investigated by in vivo and in vitro model.ResultsOur results demonstrated significant upregulation of IL-22 in human CC tumor infiltrated leukocytes (TILs) compared to peripheral lymphocytes. Moreover, our findings demonstrated that IL-22 expression was significantly higher in ulcerative colitis (UC) tissues versus normal colon tissues. Both IL-22 receptor α1 (IL-22RA1) and IL-23 were highly expressed in CC and UC tissues compared to normal controls. TILs exhibiting various IL-22 expression levels isolated from CC patients were demonstrated to enhance tumor growth and metastasis co-transplanted with Hct-116 cells underwent subcutaneous transplantation in mice model. Tumor growth and metastasis was promoted by STAT3 phosphorylation and upregulation of its downstream genes such as Bcl-xl, CyclinD1, and VEGF. In vitro studies confirmed the anti-apoptotic and pro-proliferation effect of IL-22 according to the BrdU cooperation assay and peroxide induced apoptosis analysis with or without the presence of IL-22.ConclusionIn this study we demonstrated that excessive IL-22 in the CC and UC microenvironment leads to tumor growth, inhibition of apoptosis, and promotion of metastasis depend on STAT3 activation.

HULC and Linc00152 Act as Novel Biomarkers in Predicting Diagnosis of Hepatocellular Carcinoma

Background/Aims: The alterations of long non-coding RNAs (lncRNAs) are related to multiple diseases. They can be detected in plasma as biomarkers for the diagnosis of multiple diseases. In this study, we aimed to determine the expression of circulating lncRNAs in human, which may be promising biomarkers for the diagnosis of hepatocellular carcinoma (HCC). Methods: Eight lncRNAs were chosen as candidates on the basis of the literature to evaluate the diagnostic value and accuracy of the plasma lncRNA profiling system. The candidate lncRNAs were validated by qRT-PCR arranged in the training and validation sets. Additional double-blind testing was performed in 20 patients clinically suspected of having HCC. Results: Circulating HULC and Linc00152 were significantly up-regulated in plasma samples of HCC patients during training set and validation set. Areas under the receiver operating characteristic (ROC) curves of the validated two lncRNAs signature were 0.78 and 0.85, respectively. Combination of HULC and Linc00152 possessed a moderate ability to discrimination between HCC and control with an area under ROC value of 0.87 while the combination of AFP was 0.89 with a positive correlation with tissues expression. Conclusions: Our results suggest that both plasma levels of HULC and Linc00152 achieve a fine diagnostic accuracy in diagnosing ontogenesis and metastasis of HCC and may act as novel biomarkers for HCC.

A novel biomarker Linc00974 interacting with KRT19 promotes proliferation and metastasis in hepatocellular carcinoma

Location-associated long noncoding RNA (lncRNA) was reported to interact with target protein via a cis-regulatory process especially for the Flank10kb class lncRNA. Based on this theory, we aimed to explore the regulatory mechanisms of Linc00974 and KRT19 (an lncRNA beyond the Flank10kb class with protein) when we first confirmed the aberrant expression in hepatocellular carcinoma in a previous study. Knockdown of Linc00974 resulted in an inhibition of cell proliferation and invasion with an activation of apoptosis and cell cycle arrest in vitro, which was also validated by a subcutaneous and tail vein/intraperitoneal injection xenotransplantation model in vivo. We further investigated the interaction pattern of Linc00974 and KRT19. MiR-642 was identified, by acting as the competing endogenous RNA in regulating Linc00974 and KRT19. Linc00974 was increased owing to an abnormal hypomethylation promoter, which induced the upregulation of KRT19 via ceRNA interaction, resulting in the activation of the Notch and TGF-β pathways as detected by cDNA microarray. We also discovered Linc00974F-1 stably expressed in the plasma. By the combined analysis of Linc00974F-1 with CYFRA21-1, we found that these joint indicators predicted growth and metastasis of tumor in HCC patients. In conclusion, the combination of Linc00974 and KRT19 may be novel indices for clinical diagnosis of tumor growth and metastasis in HCC, while Linc00974 may become a potential therapeutic target for the prevention of HCC progression.

LINC00152 promotes proliferation in hepatocellular carcinoma by targeting EpCAM via the mTOR signaling pathway

Hepatocellular carcinoma (HCC) is well known as the sixth most common malignant tumor and the third leading cause of cancer-related deaths globally. LINC00152 was documented as an important long non-coding RNA (lncRNA) involved in the pathogenesis of gastric cancer; however, the detailed mechanism of action of LINC00152 remains unknown. Here, based on the increased level of LINC00152 in HCC tissues, we found that LINC00152 could promote cell proliferation in vitro and tumor growth in vivo. Furthermore, microarray-based analysis indicated that LINC00152 could activate the mechanistic target of rapamycin(mTOR) pathway by binding to the promoter of EpCAM through a cis-regulation, as confirmed by Gal4-λN/BoxB reporter system. Thus, LINC00152 might be involved in the oncogenesis of HCC by activating the mTOR signaling pathway and might be a novel index for clinical diagnosis in the future.

The aberrant expression of MEG3 regulated by UHRF1 predicts the prognosis of hepatocellular carcinoma

MEG3 as a tumor suppressor has been reported to be linked with pathogenesis of malignancies including hepatocellular carcinoma (HCC). However, the mechanism of MEG3 in HCC still remains unclear. In our study, the aberrant decreased level of MEG3 in 72 tumor tissues obtained from HCC patients and cell lines was examined by using real‐time PCR. The inhibition affection in proliferation and inducing affection in apoptosis was further confirmed in vivo and vitro, we also demonstrated that MEG3 regulates HCC cell proliferation and apoptosis partially via the accumulation of p53. Besides, the hypermethylation of MEG3 in promoter region was identified by bisulfite sequencing while MEG3 increased with the inhibition of methylation. Subsequently, UHRF1, a new identified oncogene which is required for DNA methylation and recruits, was investigated. A negative correlation of MEG3 and UHRF1 expression was verified in primary HCC tissues. Down‐regulation of UHRF1 induced MEG3 expression in HCC cell lines, which could be reversed by the up‐regulation of UHRF1. In addition, up‐regulation of MEG3 in HCC cells partially diminished the promotion of proliferation induced by UHRF1. Moreover, Kaplan–Meier analysis demonstrated that the patients with low expression of MEG3 indicated worse overall and relapse‐free survivals compared with high expression of MEG3. Cox proportional hazards analyses showed that MEG3 expression was an independent prognostic factor for HCC patients. In conclusion, we demonstrated MEG3, acting as a potential biomarker in predicting the prognosis of HCC, was regulated by UHRF1 via recruiting DNMT1 and regulated p53 expression.

High expression levels of IKKα and IKKβ are necessary for the malignant properties of liver cancer

IKK‐NF‐κB signaling is regarded as an important factor in hepatocarcinogenesis and a potential target for liver cancer therapy. Therefore, in this study, we analyzed the expression of mRNAs encoding components and targets of NF‐κB signaling including IKKα, IKKβ, RANK, RANKL, OPG, CyclinD3, mammary serine protease inhibitor (Maspin), CyclinD1, c‐FLIP, Bcl‐xl, Stat3, Cip1 and Cip2 by real‐time PCR in 40 patients with liver cancer. After statistical analysis, 7 indices including IKKα, IKKβ, RANK, Maspin, c‐FLIP, Cip2 and cyclinD1 were found to show significant differences between tumor tissue and its corresponding adjacent tissue. When IKKα and IKKβ were downregulated in the hepatocellular carcinoma (HCC) cell lines of MHCC‐97L and MHCC‐97H in vitro, the numbers of BrdU positive cells were decreased in both IKKα and IKKβ knockdown cells. Levels of apoptosis were also investigated in IKKα and IKKβ knockdown cells. The growth of HCC was inhibited in the subcutaneous implantation model, and lung metastatogenesis was also significantly inhibited in the kidney capsule transplantation model. Downregulation of IKKα and IKKβ in HCC cultured in vitro revealed that increased Maspin, OPG and RANKL expression was associated with metastasis of HCC. These findings were associated with downregulation of Bcl‐XL and c‐FLIP, which may be the reason for increased apoptosis. The therapeutic effect of IKKα and IKKβ downregulation depends on extent of NF‐κB inhibition and the malignant nature of the HCC. We anticipate that IKK‐targeted gene therapy can be used in the treatment of HCC, a cancer that is notoriously resistant to radiation and chemotherapy.

miR-22 Promotes HBV-Related Hepatocellular Carcinoma Development in Males

Purpose: Previous reports have shown that IL-1α–MyD88–IL-6 signaling is essential in promoting hepatocellular carcinoma (HCC) development in a diethylnitrosamine (DEN)-induced mouse model. We aimed to determine whether interleukin (IL)-1α regulates HCC development in humans. Methods: HBV-associated HCC tissue, corresponding adjacent tissue, and normal tissue samples were obtained from 80 male and 36 female patients. IL-1α, ERα, IL-6, and MyD88 were quantified by using real-time PCR and Western blot. Stem-loop PCR was used to quantify miR-22 expression. Luciferase reporter assays were used to study transcriptional regulation. Results: IL-1α was highly expressed in male tumor adjacent tissue compared with normal tissue (P = 0.025); however, this was not the case for female subjects. A linear relationship was observed between increased IL-1α and decreased ERα expression in male tumor adjacent tissue (r = −0.616, P = 0.004). Our results also indicated that estrogen (E2) was suppressed upon IL-1α secretion in ERα-overexpressed HCC cells. We detected high expression of miR-22 in male tumor adjacent tissue compared with controls (P = 0.027); furthermore, we showed that miR-22 downregulates ERα transcription by targeting the 3′-untranslated region. In the DEN-induced model, IL-1α was highly expressed in sprouting tumors and gradually decreased in conjunction with HCC development. Conclusion: Overexpression of miR-22 in male tumor adjacent tissue was associated with downregulated ERα expression, potentially by attenuating the protective effect of estrogen and causing increased IL-1α expression. These results may explain the high incidence of HBV-associated HCC in the male population. Clin Cancer Res; 17(17); 5593–603. ©2011 AACR.

Estrogen‐sensitive PTPRO expression represses hepatocellular carcinoma progression by control of STAT3

Protein tyrosine phosphatase receptor type O (PTPRO), one of the receptor types of phosphotyrosine phosphatases (PTP), was recently described as a tumor suppressor in various kinds of cancers. We aimed to clarify the role of PTPRO in hepatocellular carcinoma (HCC). It was demonstrated in 180 pairs (120 male and 60 female) of clinical HCC specimens that the PTPRO level was significantly reduced, as compared with adjacent tissue, and the PTPRO level in male adjacent tissue was lower than in female. We further found that estrogen receptor alpha (ERα) could up‐regulate PTPRO expression as a transcription factor. Moreover, an in vitro study showed that cell proliferation was inhibited and apoptosis was promoted in PTPRO‐transduced HCC cell lines, whereas an in vivo study represented that tumor number and size was increased in ptpro−/− mice. As a result of its tumor‐suppressive position, PTPRO was proved to down‐regulate signal transducers and activators of transcription (STAT3) activity dependent on Janus kinase 2 (JAK2) and phosphoinositide 3‐kinase (PI3K) dephosphorylation. Conclusions: PTPRO expression results in pathological deficiency and gender bias in HCC, which could be attributed to ERα regulation. The suppressive role of PTPRO in HCC could be ascribed to STAT3 inactivation. (HEPATOLOGY 2013)