Activation of c-Jun N-terminal kinase in non-cancerous liver tissue predicts a high risk of recurrence after hepatic resection for hepatocellular carcinoma

GRP75-mediated upregulation of HMGA1 stimulates stage I lung adenocarcinoma progression by activating JNK/c-JUN signaling

Background

Recurrence is a major challenge in early‐stage lung adenocarcinoma (LUAD) treatment. Here, we investigated the role and mechanism of high‐mobility group AT‐hook 1 (HMGA1) and glucose‐regulated protein 75‐kDa (GRP75) in stage I LUAD and evaluated their potential as biomarkers for predicting the recurrence and prognosis of stage I LUAD.

Methods

The TCGA dataset was used to investigate the clinical significance of HMGA1 and GRP75 in early‐stage LUAD. The biological functions of HMGA1 and GRP75 in LUAD were investigated both in vitro and in vivo through overexpression and knockdown experiments. The interaction and regulation between HMGA1 and GRP75 were evaluated with coimmunoprecipitation and ubiquitination assays. The downstream signaling pathway of the GRP75/HMGA1 axis was investigated by mRNA‐sequencing analysis.

Results

Both HMGA1 expression levels and GRP75 expression levels were associated with recurrence in stage I LUAD patients. In particular, HMGA1 had potential as an independent prognostic factor in stage I LUAD patients. Overexpression of GRP75 or HMGA1 significantly stimulated LUAD cell growth and metastasis, while silencing GRP75 or HMGA1 inhibited LUAD cell growth and metastasis in vitro and in vivo. Importantly, GRP75 inhibited ubiquitination‐mediated HMGA1 degradation by directly binding to HMGA1, thereby causes HMGA1 upregulation in LUAD. In addition, the GRP75/HMGA1 axis played its role by activating JNK/c‐JUN signaling in LUAD.

Conclusions

The activation of GRP75/HMGA1/JNK/c‐JUN signaling is an important mechanism that promotes the progression of stage I LUAD, and a high level of HMGA1 is a novel biomarker for predicting recurrence and a poor prognosis in stage I LUAD patients.

Gankyrin induces STAT3 activation in tumor microenvironment and sorafenib resistance in hepatocellular carcinoma

Most hepatocellular carcinomas (HCC) develop as a result of chronic liver inflammation. We have shown that the oncoprotein gankyrin is critical for inflammation‐induced tumorigenesis in the colon. Although the in vitro function of gankyrin is well known, its role in vivo remains to be elucidated. We investigated the effect of gankyrin in the tumor microenvironment of mice with liver parenchymal cell‐specific gankyrin ablation (Alb‐Cre;gankyrin^f/f) and gankyrin deletion both in liver parenchymal and non‐parenchymal cells (Mx1‐Cre;gankyrin^f/f). Gankyrin upregulates vascular endothelial growth factor expression in tumor cells. Gankyrin binds to Src homology 2 domain‐containing protein tyrosine phosphatase‐1 (SHP‐1), mainly expressed in liver non‐parenchymal cells, resulting in phosphorylation and activation of signal transducer and activator of transcription 3 (STAT3). Gankyrin deficiency in non‐parenchymal cells, but not in parenchymal cells, reduced STAT3 activity, interleukin (IL)‐6 production, and cancer stem cell marker (Bmi1 and epithelial cell adhesion molecule [EpCAM]) expression, leading to attenuated tumorigenic potential. Chronic inflammation enhances gankyrin expression in the human liver. Gankyrin expression in the tumor microenvironment is negatively correlated with progression‐free survival in patients undergoing sorafenib treatment for HCC. Thus, gankyrin appears to play a critical oncogenic function in tumor microenvironment and may be a potential target for developing therapeutic and preventive strategies against HCC.

Association of long noncoding RNA and c-JUN expression in hepatocellular carcinoma

BACKGROUND

Long noncoding RNAs(lncRNAs) have emerged as key elements in modulating gene expression in different biological contexts.

PATIENTS AND METHODS

We used quantitative real-time PCR (Qpcr) to evaluate the expression of lncRNA-UCA1 and C-JUN in serum of 70 patients with hepatocellular carcinoma (HCC), 32 patients chronic hepatitis C (CHC) and 38 healthy subjects and their correlation with different clinicopathological factors.

RESULTS

The expression of lncRNA-UCA1 and C-JUN was positive in 91.4%HCC patients with strong discriminating power between HCC and healthy subjects and CHC patients as well. The median follow up period was 29 months. The survival analysis showed that both lncRNA-UCA1 and C-JUN were independent prognostic factors. Of note, we identified C-JUN expression changes consistent with the lncRNA-UCA1 target regulation.

CONCLUSION

This information sheds light on the possible role of lncRNA-UCA1 and C-JUN mRNA as promising diagnostic and prognostic markers as well as potential therapeutic targets in HCC.

JNK signaling in hepatocarcinoma cells is associated with the side population upon treatment with anticancer drugs

Liver cancer is one of the most drug-resistant cancer types, and cancer stem cells are related to drug resistance. c-Jun-N-terminal kinase (JNK) signaling is involved in drug resistance, and the side population of cells (SP cells) can be used as a model to study liver cancer stem cells. We sought to evaluate the relationship between SP cells and JNK signaling in hepatocarcinoma cells. For this purpose, we examined cell proliferation and the SP cell ratio following treatment of Huh7 cells with the anticancer drugs 5-fluorouracil (5-FU) and paclitaxel. The expression of phospho-stress-activated protein kinase (SAPK)/JNK in the treated cells was evaluated using immunoblotting. 5-FU and paclitaxel treatment increased the number of SP cells and JNK phosphorylation, and decreased cell survival. Huh7 and HepG2 cells were also treated with SP600125, a JNK inhibitor, to study the relationship between SP cells and JNK signaling. The increase in the number of SP cells and the SAPK/JNK and c-Jun phosphorylation was reverted by SP600125 treatment in these cells. We also used immunohistochemistry and showed that SAPK/JNK and c-Jun phosphorylation are increased in hepatocarcinoma tissues. In conclusion, our results demonstrate that the number of SP cells and SAPK/JNK phosphorylation are increased upon treatment with anticancer drugs, and that this increase is blocked by inhibition of JNK signaling. These findings suggest that drug resistance in liver cancer may involve an increase in the number of SP cells following JNK activation.

ABCB6 mRNA and DNA methylation levels serve as useful biomarkers for prediction of early intrahepatic recurrence of hepatitis C virus-related hepatocellular carcinoma

The poor prognosis of hepatocellular carcinoma (HCC) can be explained largely by the high rate of intrahepatic recurrence (IHR). Identification of genes related to IHR is needed to improve the poor prognosis and important for personalized medicine. Eighty-one HCC specimens were used in this study. We screened for IHR-related genes by DNA microarray analysis. The validation of screening was performed by using real-time PCR. The methylation levels in genomic DNAs were measured by quantitative methylation-specific PCR. Six hepatoma cell lines were used for examination of ABCB6 expressional regulation. Time-to-event analyses for recurrence after surgery were analyzed by Kaplan-Meier analysis and Cox regression analysis with cutoff values obtained from receiver operating characteristic (ROC) analysis. We confirmed that ABCB6 mRNA levels were significantly higher in hepatitis C virus (HCV)-related HCCs with early IHR compared to HCV-related HCCs without early IHR (2.5-fold, P=0.01) and the corresponding non-cancerous livers (3.1-fold, P=0.05). Experiments with cell lines showed correlation between DNA methylation and mRNA levels of ABCB6. ROC analysis revealed that mRNA levels (0.81 area under the curve, 88% sensitivity and 72% specificity) and DNA methylation levels (0.81 area under the curve, 80% sensitivity and 80% specificity) of ABCB6 in HCV-related HCCs allowed for the accurate discrimination of the development of early IHR. Cox regression analysis revealed that ABCB6 mRNA levels was an independent risk factor for IHR of HCV-related HCC. Aberrant mRNA and DNA methylation levels of ABCB6 may serve as useful predictive biomarkers for early IHR of HCV-related HCC.

An unusual recurrence site for HCC!

BACKGROUND

Hepatocellular carcinoma (HCC) is the first malignant hepatic tumor in frequency, with an incidence of 10 new cases per 100,000 people a year, in France. HCC metastasis disseminate hematogenously. The most frequent metastatic sites are lungs, bones, and liver.

PATIENTS AND METHODS

We detail the approach to diagnosis and the treatment of a patient with an unusual late recurrence of HCC, which was discovered fortuitously. The metastasis was located in the subcutaneous tissue of the right gluteal fold.

CONCLUSION

This case poses a problem of detection in the clinical practice. Indeed, the recurrence occurred 9 years after the HCC. Molecular analysis of our case could make us progress in our knowledge of this disease, and to associate it to a patient's group with similar HCC evolutive profile.

Activation of JNK and high expression level of CD133 predict a poor response to sorafenib in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) ranks as the third leading cause of cancer deaths worldwide. While sorafenib, a multikinase inhibitor targeting the Raf/extracellular signal-regulated protein kinase (ERK) pathway, has been shown recently to provide a survival advantage to patients with advanced HCC, a predictive biomarker has not been developed. We studied whether c-Jun N-terminal kinase (JNK), which promotes liver carcinogenesis in mice, affects therapeutic response to sorafenib in HCC patients.

METHODS

We collected pathological specimens from 39 patients with advanced HCC before starting sorafenib treatment, and measured JNK activity in HCCs.

RESULTS

In patients treated with sorafenib, the expression of phospho-c-Jun in HCC, as a read out of JNK activity, was significantly higher (P<0.001) in the non-responder group than in the responder group. c-Jun N-terminal kinase activation in HCC was associated with a decreased time to progression and a poor overall survival (P=0.0028 and P=0.0008, respectively).

CONCLUSION

In addition, JNK activity was significantly correlated with CD133 expression level. Correspondingly, high expression level of CD133 was linked to a poor response to sorafenib. Furthermore, D-JNKi, a specific JNK inhibitor, reduced the growth of xenografted CD133(+) cells in athymic mice. In conclusion, JNK activation was positively correlated with CD133 expression level and inversely correlated with the therapeutic response to sorafenib, suggesting that JNK activity may be considered as a new predictive biomarker for response to sorafenib treatment.

Molecular mechanisms of liver injury and hepatocarcinogenesis: focusing on the role of stress-activated MAPK

Hepatocellular carcinoma (HCC) is the third most common cause of cancer mortality. Short-term prognosis of patients with HCC has improved recently due to advances in early diagnosis and treatment, but long-term prognosis is still unsatisfactory. Therefore, obtaining a further understanding of the molecular carcinogenic mechanisms and the unique pathogenic biology of HCC is important. The most characteristic process in hepatocarcinogenesis is underlying chronic liver injury, which leads to repeated cycles of hepatocyte death, inflammation, and compensatory proliferation and subsequently provides a mitogenic and mutagenic environment leading to the development of HCC. Recent in vivo studies have shown that the stress-activated mitogen-activated protein kinase (MAPK) cascade converging on c-Jun NH(2)-terminal kinase (JNK) and p38 plays a central role in these processes, and it has attracted considerable attention as a therapeutic target. However, JNK and p38 have complex functions and a wide range of cellular effects. In addition, crosstalk with each other and the nuclear factor-kappaB pathway further complicate these functions. A full understanding is essential to bring these observations into clinical settings. In this paper, we discuss the latest findings regarding the mechanisms of liver injury and hepatocarcinogenesis focusing on the role of the stress-activated MAPK pathway.