Genomic analysis reveals RhoC as a potential marker in hepatocellular carcinoma with poor prognosis

ARAP1 negatively regulates stress fibers formation and metastasis in lung adenocarcinoma via controlling Rho signaling

Small GTPases regulate multiple important cellular behaviors and their activities are strictly controlled by a mass of regulators. The dysfunction or abnormal expression of small GTPases or their regulators was frequently observed in various cancers. Here, we analyzed the expression and prognostic correlation of several GTPases and related regulators based on the TCGA database and found that Ankyrin Repeat and PH Domain 1 (ARAP1), a GTPase activating protein (GAP), is reduced in lung adenocarcinoma tissues compared to normal tissues and displays a positive correlation with overall survival (OS) and progression-free survival (PFS) of patients with lung adenocarcinoma. qPCR and western blot verified that ARAP1 is frequently downregulated in lung adenocarcinoma tumor tissues and cancer cells, and its downregulation might be mediated by epigenetic modification. Moreover, metastatic assays showed that overexpression of ARAP1 significantly inhibits metastasis of lung adenocarcinoma in vitro and in vivo. We further demonstrated that Rho signaling inhibition, mediated by RhoGAP activity of ARAP1, majorly contributes to suppressing migration and invasion of lung adenocarcinoma cancer cells via inhibiting stress fibers formation. In summary, this study indicates that ARAP1 may serve as a potential prognostic predictor and a metastatic suppressor in lung adenocarcinoma via its RhoGAP activity.

Association of tumor morphology with long-term prognosis after liver resection for patients with a solitary huge hepatocellular carcinoma-a multicenter propensity score matching analysis

BACKGROUND

A solitary hepatocellular carcinoma (HCC) without macrovascular invasion and distant metastasis, regardless of tumor size, is currently classified as early-stage disease by the latest Barcelona Clinic Liver Cancer (BCLC) staging system. While the preferred treatment is surgical resection, the association of tumor morphology with long-term survival outcomes after liver resection for a solitary huge HCC of ≥10 cm has not been defined.

METHODS

Patients who underwent curative liver resection for a solitary huge HCC were identified from a multicenter database. Preoperative imaging findings were used to define spherical- or ellipsoidal-shaped lesions with smooth edges as balloon-shaped HCCs (BS-HCCs); out-of-shape lesions or lesions of any shape with matt edges were defined as non-balloon-shaped HCCs (NBS-HCCs). The two groups of patients with BS-HCCs and NBS-HCCs were matched in a 1:1 ratio using propensity score matching (PSM). Clinicopathologic characteristics, long-term overall survival (OS) and recurrence-free survival (RFS) were assessed.

RESULTS

Among patients with a solitary huge HCC, 74 pairs of patients with BS-HCC and NBS-HCC were matched. Tumor pathological features including proportions of microvascular invasion, satellite nodules, and incomplete tumor encapsulation in the BS-HCC group were lower than the NBS-HCC group. At a median follow-up of 50.7 months, median OS and RFS of all patients with a solitary huge HCC after PSM were 27.8 and 10.1 months, respectively. The BS-HCC group had better median OS and RFS than the NBS-HCC group (31.9 vs. 21.0 months, P=0.01; and 19.7 vs. 6.4 months, P=0.015). Multivariate analyses identified BS-HCC as independently associated with better OS (HR =0.592, P=0.009) and RFS (HR =0.633, P=0.013).

CONCLUSIONS

For a solitary huge HCC, preoperative imaging on tumor morphology was associated with prognosis following resection. In particular, patients with BS-HCCs had better long-term survival following liver resection versus patients with large NBS-HCCs.

Piezo1 promoted hepatocellular carcinoma progression and EMT through activating TGF-β signaling by recruiting Rab5c

BACKGROUND

Piezo1 has been revealed to play a regulatory role in vascular development and progression of variety tumors. However, whether and how the progression of hepatocellular carcinoma (HCC) regulated by Piezo1 remains elusive. This study aimed to elucidate the effect and mechanisms of Piezo1 in HCC.

METHODS

The mRNA and protein expression level of Piezo1 in HCC samples and cell lines was determined by qRT-PCR, western blot and immunohistochemistry analyses. Two independent study cohorts containing 280 patients were analyzed to reveal the association between Piezo1 expression and clinicopathological characteristics. Series of in vitro and in vivo experiments were used to validate the function of Piezo1 in HCC. Gene set enrichment analysis (GSEA) was performed to explore the signaling pathway of Piezo1. Immunoprecipitation, immunofluorescence and in vitro and in vivo experiments were used to explore the molecular mechanism of Piezo1 in HCC progression.

RESULTS

Our results demonstrated the Piezo1 expression was significantly upregulated in HCC tissues and cell lines, and upregulation of Piezo1 closely correlated with aggressive clinicopathological features and poor prognosis. Knockdown of Piezo1 in HCCLM3 and Hep3B cells significantly restrained proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of HCC cells in vitro, and tumor growth, metastasis, EMT in vivo. TGF-β signaling pathway was most significant enriched pathway in GSEA. Finally, tumor promotion effect of Piezo1 was found to exerted through recruiting and combining Rab5c to activating TGF-β signaling pathway.

CONCLUSIONS

Piezo1 significantly related to poor prognosis and promotes progression of hepatocellular carcinoma via activating TGF-β signaling, which suggesting that Piezo1 may serve as a novel prognostic predictor and the potential therapeutic target for HCC patients.

NAD(P)HX epimerase downregulation promotes tumor progression through ROS/HIF-1α signaling in hepatocellular carcinoma

Reactive oxygen species (ROS) derived from aberrant tumor metabolism could contribute to tumor invasion and metastasis. NAD(P)HX Epimerase (NAXE), an epimerase that allows the repair of damaged forms of antioxidant NADPH, is a potential cellular ROS scavenger and its role in tumor development is still elusive. Here, we found that NAXE is significantly downregulated in hepatocellular carcinoma (HCC) tissues and cell lines. NAXE downregulation is associated with poor clinicopathological characteristics and is an independent risk factor for overall and disease‐free survival of HCC patients after liver resection. In addition, low NAXE expression could identify worse prognosis of HCC patients before vascular invasion or in early stages of disease. In particularly, low NAXE expression in HCC is markedly associated with microvascular invasion (MVI) and its combination with MVI predicts poorer prognosis of HCC patients after liver resection. Furthermore, in vitro and in vivo experiments both showed that knockdown of NAXE expression in HCC cells promoted migration, invasion, and metastasis by inducing epithelial‐mesenchymal transition (EMT), whereas NAXE overexpression causes the opposite effects. Mechanistically, low NAXE expression reduced NADPH levels and further caused ROS level increase and hypoxia‐inducible factor‐1α (HIF‐1α) activation, thereby promoting invasion and metastasis of HCC by facilitating EMT. What is more, the tumor‐promoting effect of NAXE knockdown in HCC xenograft can be abolished by giving mice N‐acetyl‐l‐cysteine (NAC) in drinking water. Taken together, our findings uncovered a tumor suppressor role for NAXE in HCC by scavenging excessive ROS and inhibiting tumor‐promoting signaling pathways, suggesting a new strategy for HCC therapy by targeting redox signaling.

EB2 promotes hepatocellular carcinoma proliferation and metastasis via MAPK/ERK pathway by modulating microtubule dynamics

Metastasis is the main cause of poor postoperative survival of hepatocellular carcinoma (HCC) patients. Cytoskeleton rearrangement is a key event in cancer metastasis. However, the significance of microtubule (MT), one of the core components of cytoskeleton, in this process is only beginning to be revealed. Here, we find that the MT dynamics regulator end-binding protein 2 (EB2) is highly expressed in HCC and predicts poor prognosis of HCC patients. Functional studies show that EB2 overexpression promotes HCC proliferation, invasion and metastasis in vitro and in vivo, while EB2 knockdown has opposite results. Mechanistically, EB2 mediates MTs destabilization, increases Src (Src proto-oncogene non-receptor tyrosine kinase) activity, and thus facilitates extracellular signal-regulated kinase (ERK) signaling activation, which could in turn promote EB2 expression in HCC, eventually resulting in enhanced HCC proliferation, invasion and metastasis. Furthermore, U0126, a specific ERK inhibitor, could effectively inhibit EB2-mediated HCC proliferation and metastasis in vitro and in vivo. In conclusion, EB2 coordinates MT cytoskeleton and intracellular signal transduction, forming an EB2-MT-ERK positive feedback loop, to facilitate HCC proliferation, invasion and metastasis. EB2 could serve as a promising prognostic biomarker and potential therapeutic target for HCC; HCC patients with high EB2 expression may benefit from treatment with ERK inhibitors.

Leukemia-Associated Rho Guanine Nucleotide Exchange Factor and Ras Homolog Family Member C Play a Role in Glioblastoma Cell Invasion and Resistance

Glioblastoma (GBM) is the most common primary malignant brain cancer in adults. A hallmark of GBM is aggressive invasion of tumor cells into the surrounding normal brain. Both the current standard of care and targeted therapies have largely failed to specifically address this issue. Therefore, identifying key regulators of GBM cell migration and invasion is important. The leukemia-associated Rho guanine nucleotide exchange factor (LARG) has previously been implicated in cell invasion in other tumor types; however, its role in GBM pathobiology remains undefined. Herein, we report that the expression levels of LARG and ras homolog family members C (RhoC), and A (RhoA) increase with glial tumor grade and are highest in GBM. LARG and RhoC protein expression is more prominent in invading cells, whereas RhoA expression is largely restricted to cells in the tumor core. Knockdown of LARG by siRNA inhibits GBM cell migration in vitro and invasion ex vivo in organotypic brain slices. Moreover, siRNA-mediated silencing of RhoC suppresses GBM cell migration in vitro and invasion ex vivo, whereas depletion of RhoA enhances GBM cell migration and invasion, supporting a role for LARG and RhoC in GBM cell migration and invasion. Depletion of LARG increases the sensitivity of GBM cells to temozolomide treatment. Collectively, these results suggest that LARG and RhoC may represent unappreciated targets to inhibit glioma invasion.

Expression And Biological Interaction Network Of RHOC For Hepatic Carcinoma With Metastasis In PBMC Samples

Objectives

Hepatic carcinoma with metastasis remains incurable, and clinical diagnostic methods lacked adequate sensitivity and specificity. Therefore, seeking effectively diagnostic biomarkers is still essential for it. RHOC was reported to be linked to metastasis of hepatic carcinoma. However, almost all of the studies used tissues as detection samples, which was not ideal for clinical course minoring. Therefore, here, it was aimed to use PBMC samples that were not only easily accessible but also minimally invasive to determine the expression and biological interaction network of RHOC for hepatic carcinoma with metastasis.

Methods

PBMC samples were isolated. Then, RNA-seq was performed to identify the DEGs between hepatic carcinoma with metastasis and hepatic carcinoma with solitary tumor. Subsequently, q-RT-PCR was used to verify the expression level of RHOC. Finally, bioinformatic analysis was used to present the biological interaction network of RHOC for hepatic carcinoma with metastasis in PBMC samples.

Results

The results of both RNA-seq and q-RT-PCR showed that the expression level of RHOC was significantly higher in the PBMC samples of hepatic carcinoma with metastasis than in those of hepatic carcinoma with solitary tumor. By using variety of bioinformatic analysis platforms, in PBMCs, 18 co-expression genes with RHOC were identified and their interaction network showed that MYL9 and RHOC had the highest edge evidence, and were involved in some cell migration-related pathways.

Conclusion

Our results indicated that RHOC in PBMCs could be potentially minimally invasive indicators for the diagnosis and clinical course supervision of hepatic carcinoma with metastasis, and its biological interaction network determined based on bioinformatic methods would lay a foundation for further study of the role of RHOC in tumor invasion and metastasis.

Overexpression of Pin1 and rho signaling partners correlates with metastatic behavior and poor recurrence-free survival of hepatocellular carcinoma patients

Background

Identification of molecular markers for early detection or prediction of metastasis is crucial for both management of HCC patient postoperative treatment and identify new therapeutic targets to inhibit HCC progression and metastasis. In the current study, we investigated the clinical correlation between Pin1, RhoA and RhoC and their association with HCC metastasis.

Methods

Using a randomized study design of primary HCC samples from 139 patients, we determined messenger RNA expression of Pin1, RhoA and RhoC and their prognostic value.

Results

Our findings demonstrated for the first time the clinical correlation of Pin1 in HCC metastasis. Pin1, RhoA and RhoC transcript levels were significantly higher in HCC specimens when compared with the paired adjacent non-tumorous liver. Pin1 overexpression was closely correlated with that of RhoA (R = 0.562, p < 0.001) and RhoC (R = 0.529, p < 0.001), and their co-overexpressions correlated with metastatic HCC (p = 0.000012) and poor recurrence-free survival of HCC patients (p < 0.00001), which showed better prognostic significance than either Pin1, RhoA or RhoC overexpression alone. Co-overexpressions of Pin1 + RhoA/RhoC were also an independent factor for predicting development of metastasis after curative resection in our multivariate regression model (p < 0.001).

Conclusion

Pin1, RhoA and RhoC co-overexpressions are prognostic factor for metastatic HCC and predict poor recurrence-free survival.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5919-3) contains supplementary material, which is available to authorized users.

miR-330-5p targets SPRY2 to promote hepatocellular carcinoma progression via MAPK/ERK signaling

MicroRNAs (miRNAs) have been identified as critical modulators of cell proliferation and growth, which are the major causes of cancer progression including hepatocellular carcinoma (HCC). Our previous miRNA microarray data have shown that miR-330-5p was always upregulated in HCC. However, the accurate role of miR-330-5p in HCC is still uncertain. Here, we report that miR-330-5p expression is upregulated in HCC tissues and cell lines, and is associated with tumor size, tumor nodule number, capsule formation and Tumor Node Metastasis (TNM) stage in HCC patients. Overexpression of miR-330-5p promotes proliferation and growth of HCC cells in vitro and in vivo, while miR-330-5p knockdown has the inverse effect. Moreover, using miRNA databases and dual luciferase report assay, we find miR-330-5p directly binds to the 3′-untranslated region (3′-UTR) of Sprouty2 (SPRY2). Then we find the novel biofunctional role of SPRY2 inactivation in promoting HCC progression. Finally, we confirm that miR-330-5p suppresses SPRY2 to promote proliferation via mitogen-activated protein kinases (MAPK)/extracellular regulated kinase (ERK) signaling in HCC. Taken together, our findings demonstrate the critical role of miR-330-5p in promoting HCC progression via targeting SPRY2 to activate MAPK/ERK signaling, which may provide a novel and promising prognostic marker and therapeutic target for HCC.

YMO1 suppresses invasion and metastasis by inhibiting RhoC signaling and predicts favorable prognosis in hepatocellular carcinoma

Previous studies have shown that 4.1 proteins, which are deregulated in many cancers, contribute to cell adhesion and motility. Yurt/Mosaic eyes-like 1 (YMO1) is a member of 4.1 protein family but it is unclear whether YMO1 plays a role in tumor invasion. This study aimed to investigate the effects of YMO1 on hepatocellular carcinoma (HCC) and attempted to elucidate the underlying molecular mechanisms. YMO1 expression in HCC tissues and its correlation with clinicopathological features and postoperative prognosis was analyzed. The results showed that YMO1 was down-regulated in the highly metastatic HCC cell line and in human tumor tissues. Underexpression of YMO1 indicated poor prognosis of HCC patients. Restoration of YMO1 expression caused a significant decrease in cell migration and invasiveness in vitro. In vivo study showed that YMO1 reduced liver tumor invasion and metastasis in xenograft mice. YMO1 directly inhibited RhoC activation. YMO1 expression in HCC was regulated by PAX5. Analysis of YMO1 expression levels in human HCC patients revealed a significant correlation of YMO1 expression with PAX5 and RhoC. Our findings revealed that YMO1 predicts favorable prognosis and the data suggest that YMO1 suppresses tumor invasion and metastasis by inhibiting RhoC activity.

Survival outcomes of hepatectomy for stage B Hepatocellular carcinoma in the BCLC classification

Background

Because hepatectomy is not recommended in patients with stage B hepatocellular carcinoma (HCC) of the Barcelona Clinic Liver Cancer (BCLC) staging, we evaluated the survival outcomes of hepatectomy for stage B in the BCLC system.

Methods

Data were collected from 297 consecutive adult stage B patients who underwent curative hepatectomy for HCC between 1996 and 2014 in Hokkaido University Hospital. Overall survival (OS), disease-free survival (DFS), and risk factors were analyzed using the Kaplan–Meier method. Independent prognostic factors were evaluated using a Cox proportional hazards regression model. AP-factor (alpha-fetoprotein [AFP] × protein induced by vitamin K absence or antagonism factor II [PIVKA-II]) was categorized according to the serum concentrations of AFP and PIVKA-II: AP1 (AFP < 200 ng/ml and PIVKA-II < 100 mAU/ml), AP2 (AFP × PIVKA-II < 10⁵), and AP3 (AFP × PIVKA-II ≥ 10⁵).

Results

There were 130 deaths among our 297 stage B patients (43.8%). The causes of death in these cases were HCC recurrence (n = 106; 81.5%), liver failure (n = 7; 5.4%), and other causes (n = 17; 16.1%). The operative mortality rate was 0.34% (1/297). The 5-year OS and DFS rates for the stage B cases were 54.3 and 21.9%, respectively. By multivariate analysis, tumor number and AP-factor were risk factors for both survival and recurrence that were tumor related and could be evaluated preoperatively. The study patients with stage B HCC were classified into three groups by tumor number (B1, 1; B23, 2 or 3; B4over: ≥4) and into three groups stratified by AP-factor (AP1, AP2, and AP3). The 5-year OS rates of B1, B23, and B4over were 63.6, 52.3, and 29.0%. The 5-year OS rates of AP1, AP2, and AP3 were 67.6, 65.2, and 39.1%. Stratified by the 5-year OS rate, stage B HCC patients were classified into three subgroups (A-C).The 5-year OS rates of groups A (B1 or B23 and AP-1 or AP-2), B (B1 or B23 and AP-3, or B4over and AP-1 or AP-2), and C (B4over and AP-3) were 69.5, 43.7, and 21.3%.

Conclusion

Stage B HCC patients with a tumor number ≤ 3 and/or AP-factor < 1 × 10⁵ show acceptable 5-year OS rates and could be treated by hepatectomy.

Anti-RhoC siRNAs inhibit the proliferation and invasiveness of breast cancer cells via modulating the KAI1, MMP9, and CXCR4 expression

Overexpression of RhoC in breast cancer cells indicates poor prognosis. In the present study, we aim to investigate the possible antitumor effects of anti-RhoC small-interfering RNA (siRNA) in inflammatory breast cancer cells. In this study, a specific anti-RhoC siRNA was used to inhibit RhoC synthesis. Transfection of anti-RhoC siRNA into two IBC cells SUM149 and SUM190 induced extensive degradation of target mRNA and led to significant decrease in the synthesis of protein. Anti-RhoC siRNA inhibited cell proliferation and invasion, increased cell apoptosis, and induced cell cycle arrest in vitro. Moreover, the transfection of siRNA increased the expression of KAI1 and decreased the expression of MMP9 and CXCR4 in both mRNA and protein levels. Furthermore, transplantation tumor experiments in BALB/c-nu mice showed that intratumoral injection of anti-RhoC siRNA inhibited tumor growth and increased survival rate. Our results suggested that RhoC gene silencing with specific anti-RhoC siRNA would be a potential therapeutic method for metastatic breast cancer.

MicroRNA-372 inhibits endometrial carcinoma development by targeting the expression of the Ras homolog gene family member C (RhoC)

Here we explore the role of microRNA-372 (miR-372) in tumorigenesis and development of endometrial adenocarcinoma (EC) and analyze the underlying mechanism. We found that miR-372 expression is much lower in EC than normal endometrial specimens. Cell function experiments demonstrated that miR-372 overexpression suppressed cell proliferation, migration, and invasion, and led to a G1 phase arrest and promoted the apoptosis of endometrial carcinoma cells in vitro. The nude mouse xenograft assay demonstrated that miR-372 overexpression suppressed tumor growth. RT-PCR and Western blot assays detected the expression of known targets of miR-372 in other malignant tumors and found Cyclin A1 and Cyclin-dependent Kinase 2 (CDK2) was downregulated by miR-372. Bioinformatic predictions and dual-luciferase reporter assays found that RhoC was a possible target of miR-372. RT-PCR and Western blot assays demonstrated that miR-372 transfection reduced the expression of RhoC, matrix metalloproteinase 2 (MMP2) and MMP9, while it increased the expression of cleaved poly (ADP ribose) polymerase (PARP) and bcl-2-associated X protein (Bax). The cell function experiments that transfected siRNA with RhoC showed the same trend as those which were transfected with miR-372. Taken together, our results demonstrated for the first time that miR-372 suppresses tumorigenesis and the development of EC; RhoC is a new and potentially important therapeutic target.

MicroRNA-424 inhibits Akt3/E2F3 axis and tumor growth in hepatocellular carcinoma

By comparing the expression profiles of miRNAs in different subtypes of HCC, we identified miR-424 as a HCC related miRNA. We found that the expression of miR-424 was significantly decreased in HCC tissues and six liver cancer cell lines. Significantly, its expression levels were correlated with tumor size, multiple nodules, vein invasion, TNM stage and overall survival of HCC. We showed that up-regulated miR-424 suppressed HCC cell proliferation in vivo and in vitro. Multi-pathway reporter arrays suggested that miR-424 suppressed the pRb-E2F pathway. Consistently, Akt3 and E2F3 were identified as the targets of miR-424 as evidenced by that ectopic miR-424 expression suppressed Akt3 and E2F3 expressions. Silencing Akt3 and E2F3 by siRNA pheno-copied the effect of ectopic miR-424 on HCC growth. Whereas, overexpression of Akt3 and E2F3 attenuated the effect of miR-424 on HCC growth. Together, our data demonstrated a tumor suppressor role for miR-424 in HCC development and progression with therapeutic implications. The strong correlation of miR-424 expression with HCC patient survival suggests that miR-424 could be a valuable biomarker for HCC prognosis.

Hepatic Gene Expression Changes in Mice Associated with Prolonged Sublethal Microcystin Exposure

Microcystin-LR (MCLR) is an acute hepatotoxicant and suspected carcinogen. Previous chronic studies have individually described hepatic morphologic changes, or alterations in the cytoskeleton, cell signaling or redox pathways. The objective of this study was to characterize chronic effects of MCLR in wild-type mice utilizing gene array analysis, morphology, and plasma chemistries. MCLR was given daily for up to 28 days. RNA from the 28-day study was hybridized onto mouse genechip arrays. RNA from 4 hours, 24 hours, 4 days, 1 day, and 28 days for selected genes was processed for quantitative-PCR. Increases in plasma hepatic enzyme activities and decreases in total protein, albumin and glucose concentrations were identified in MCLR-treated groups at 14 and 28 days. Histologically, marked hepatokaryomegaly was identified in the 14-day MCLR group with the addition of giant cells at 28 days. Major gene transcript changes were identified in the actin organization, cell cycle, apoptotic, cellular redox, cell signaling, albumin metabolism, and glucose homeostasis pathways, and the organic anion transport polypeptide system. Using toxicogenomics, we have identified key molecular pathways involved in chronic sublethal MCLR exposure in wild-type mice, genes participating in those critical pathways and related them to cellular and morphologic alterations seen in this and other studies.

Actin-like 6A predicts poor prognosis of hepatocellular carcinoma and promotes metastasis and epithelial-mesenchymal transition

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide because of metastasis. Epithelial-mesenchymal transition (EMT) is widely considered to be crucial to the invasion-metastasis cascade during cancer progression. Actin-like 6A (ACTL6A) is initially verified important for cell proliferation, differentiation, and migration. In this study, we find that ACTL6A plays an essential role in metastasis and EMT of HCC. ACTL6A expression is up-regulated in HCC cells and tissues. A high level of ACTL6A in HCCs is correlated with aggressive clinicopathological features and is an independent poor prognostic factor for overall and disease-free survival of HCC patients. Ectopic expression of ACTL6A markedly promotes HCC cells migration, invasion, as well as EMT in vitro and promotes tumor growth and metastasis in the mouse xenograft model. Opposite results are observed when ACTL6A is knocked down. Mechanistically, ACTL6A promotes metastasis and EMT through activating Notch signaling. ACTL6A knockdown has the equal blockage effect as the Notch signaling inhibitor, N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butylester, in HCC cells. Further studies indicate that ACTL6A might manipulate SRY (sex determining region Y)-box 2 (SOX2) expression and then activate Notch1 signaling.

CONCLUSIONS

ACTL6A promotes metastasis and EMT by SOX2/Notch1 signaling, indicating a prognostic biomarker candidate and a potential therapeutic target for HCC.

MicroRNA-130b promotes proliferation and EMT-induced metastasis via PTEN/p-AKT/HIF-1α signaling

Hepatocellular carcinoma (HCC) is a major cause of cancer-related deaths owing to its high rate of postoperative recurrence and metastasis. New research is continuously identifying novel metastasis-associated oncogenes and tumor suppressor genes. miRNAs are noncoding RNAs that regulate protein synthesis post-translationally. miR-130b is one of several miRNAs involved in tumor metastasis. However, the role of miR-130b in HCC remains controversial. Here, we demonstrate that miR-130b is highly expressed in HCC and that it correlates with tumor number, vascular invasion, and TNM stage-important predictors of postoperative recurrence and metastases. Moreover, high levels of miR-130b predicted poor overall and disease-free survival of HCC patients, and in vitro and in vivo research revealed that knockdown or overexpression of miR-130b inhibited and promoted proliferation and metastasis of HCC cells, respectively. We identified PTEN as a direct functional target of miR-130b using miRNA databases and a dual luciferase report assay. Next, using a gain and loss assay and epithelial-mesenchymal transition (EMT) relative assays, we show that miR-130b may promote proliferation and EMT-induced metastasis via PTEN/p-AKT/HIF-1α signaling. Collectively, our data suggests that miR-130b may have prognostic value in HCC. Additionally, the miR-130b/PTEN/p-AKT/HIF-1α axis identified in this study provides novel insight into the mechanisms of HCC metastasis, which may facilitate the development of new therapeutics against HCC.

Pathologic Features of Primary and Metastatic Hepatic Malignancies

In the mammalian liver, 60 % of the cellular components are hepatocytes while the remainder (35 %) includes biliary epithelium, Kupffer cells, endothelial cells, fat storing cells and connective tissue cells. Although neoplasms of hepatocytes are the most common, a significant number of both benign and malignant primary liver neoplasms arising from other cell types can develop, such as tumors of bile duct epithelium (Table 1). In addition, the liver is one of the most susceptible sites for metastatic tumors arising from other organs of the body. Not too long ago, liver tumors were left untreated because the liver was considered a complex and mysterious organ inaccessible to surgery. Advances in imaging procedures and surgical techniques over the past 40 years have revolutionized the approaches to the treatment of benign and malignant liver tumors. Subsegmentectomy, segmentectomy, lobectomy, and transplantation are routinely performed for the treatment of primary and metastatic liver tumors with minimal morbidity and mortality. Since accurate diagnosis remains the key to clinical and surgical management, the emphasis of this chapter is on classification, morphological features and differential diagnosis of malignant neoplasms of the liver.

Severely Impaired and Dysregulated Cytochrome P450 Expression and Activities in Hepatocellular Carcinoma: Implications for Personalized Treatment in Patients

This study aims to systematically determine the activities and expressions of cytochrome P450s (CYP) in hepatocellular carcinoma (HCC) patients to support their optimal use in personalized treatment of HCC. Activities of seven major drug-metabolizing CYP enzymes (CYP1A2, 2A6, 2C8, 2C9, 2D6, 2E1, and 3A4) were determined in tumors and pericarcinomatous tissues harvested from 26 patients with hepatitis B virus-positive HCC using probe substrates. Protein and mRNA levels of these CYPs were also measured using isotope label-free LC/MS-MS method and real-time PCR, respectively. Maximal metabolic velocity (Vmax) of CYP probe substrates was decreased by 2.5- to 30-fold in tumor microsomes, accompanied by a corresponding decrease in their protein and mRNA expression levels. However, Km values and turnover numbers of substrates in tumor microsomes were not changed. High correlations between activities and CYP protein levels were also observed, but the correlation between activities and mRNA levels was often poor. There was a major decrease in the degree of correlation in CYP expression in tumor tissues, suggesting that CYP expression levels are greatly disrupted by the tumorigenic process. Our unprecedented systemic study of the effects of HCC on CYPs demonstrated that activities of CYPs were seriously impaired and their expression patterns were severely altered by HCC. We proposed that determination of the CYP protein expression profile by LC/MS-MS in each patient is a promising approach that can be clinically used for individualized treatment of HCC.

MicroRNA-188-5p suppresses tumor cell proliferation and metastasis by directly targeting FGF5 in hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide. However, the detailed molecular mechanisms underlying HCC progression are still not completely clear. Given the crucial role of microRNAs (miRNAs) in cancer metastasis, we aimed to analyze the expression and function of a metastasis-associated miRNA named miR-188-5p in HCC.

METHODS

miRNA array analysis was performed to search for metastasis-associated miRNAs in HCC. miR-188-5p expressions in tumor tissues and adjacent non-tumorous liver tissues of HCC patients and cell lines were evaluated by real-time PCR. The protein expression levels were analyzed by Western blot and immunohistochemistry. Luciferase reporter assays was used to validate the target of miR-188-5p. The effect of miR-188-5p on HCC progression was studied in vitro and in vivo.

RESULTS

miR-188-5p was significantly decreased in HCC and its expression levels were highly correlated with multiple nodules, microvascular invasion, overall and disease-free survival of HCC. Ectopic expression of miR-188-5p suppressed HCC cell proliferation and metastasis in vitro and in vivo. Fibroblast growth factor 5 (FGF5) was identified as a major target of miR-188-5p. Enforced expression of miR-188-5p inhibited the expression of FGF5 significantly and the restoration of FGF5 expression reversed the inhibitory effects of miR-188-5p on HCC cell proliferation and metastasis.

CONCLUSIONS

These findings collectively demonstrate a tumor suppressor role of miR-188-5p in HCC progression via targeting FGF5, suggesting that miR-188-5p could serve as a potential prognostic biomarker and therapeutic target for HCC.

Prognostic Nomograms for Pre- and Postoperative Predictions of Long-Term Survival for Patients Who Underwent Liver Resection for Huge Hepatocellular Carcinoma

BACKGROUND

Liver resection is an effective treatment in select patients with huge hepatocellular carcinoma (HCC, diameter ≥10 cm). This study aimed to develop nomograms for pre- and postoperative predictions of overall survival (OS) for these patients.

STUDY DESIGN

There were 464 consecutive patients who underwent liver resection for huge HCC at the Eastern Hepatobiliary Surgery Hospital (EHBH) between January 2008 and December 2009. They were collected and divided into a training cohort (n = 310) and an internal validation cohort (n = 154). Another 90 patients who were operated on at the Fujian Medical University (FMU) between January 2008 and April 2010 served as an external validation cohort. The surgical morbidity, mortality, time to recurrence, and OS were observed. Two prognostic nomograms were developed based separately on the data obtained before and after surgery. Discrimination and predictive accuracy of the models were measured using concordance index (C-index), calibration curves, and validation study.

RESULTS

The postoperative 4-year tumor recurrence and OS rates were, respectively, 79.0% and 41.2% in the patients from the EHBH and 78.8% and 37.6% in those from the FMU. Independent predictors of OS on multivariable analysis using pre- and postoperative data were respectively incorporated into the 2 nomograms. In the training cohort, calibration curves for the probability of 4-year postoperative survival fitted well. The C-indexes of the pre- and postoperative nomograms in predicting OS were 0.75 (95% CI 0.72 to 0.78) and 0.78 (95% CI 0.75 to 0.81), respectively. The internal and external validation studies optimally supported these results.

CONCLUSIONS

The 2 nomograms achieved accurate pre- or postoperative predictions of long-term survival for patients with huge HCC after liver resection.

Effects of Ras homolog gene family, member C gene silencing combined with rapamycin on hepatocellular carcinoma cell growth

The aim of the present study was to investigate the combined effects of inhibiting the Ras homolog gene family, member C (RhoC)/Rho kinase and phosphoinositide 3 kinase/Akt/mammalian target of rapamycin (mTOR) pathways on hepatocellular carcinoma cell growth. The RhoC gene was silenced by RNA interference (RNAi) and mTOR was inhibited by rapamycin (RAPA). Subsequently, an MTT assay for cell growth detection, western blot analysis for gene expression analysis, silver nitrate staining for cell proliferation, Wright's staining for analysis of the apoptotic rate analysis, soft agar clonogenic assay for the determination of cell growth characteristics and a Transwell assay for cell migration were performed. RhoC expression in hepatoma cell lines was lower than that in the HL7702 normal human liver cell line. The level of cell proliferation in the RNAi + RAPA group was lower than that in the RNAi, RAPA and Scramble groups. The levels of cyclin‑dependent kinase 2 in the RNAi + RAPA group were lower than those in the other groups, while the levels of P16 in the RNAi + RAPA group were higher than those in the other experimental groups. No significant difference was found between the RNAi + RAPA and the normal HL7702 group. The number of silver nitrate‑stained particles was reduced in the RNAi + RAPA group compared with that in the other groups. No significant difference was found between the RNAi + RAPA and HL7702 groups. Wright's staining for apoptosis demonstrated that apoptosis in the Scramble group was rare, while the RAPA and RNAi groups contained a large number of apoptotic cells, which displayed nuclear condensation, fragmentation, deepened staining, as well as a wrinkled membrane. B‑cell lymphoma‑2 (Bcl‑2) expression in the RNAi + RAPA group was lower than that in the other groups, while the gene expression of Bcl‑2‑associated X protein in the RNAi + RAPA group was increased compared with that in the other groups. No cell colony formation was observed in the soft agar cloning experiment in the RNAi + RAPA and HL7702 group, while in the other groups, visible cell clones appeared. In the Transwell assay the number of migrated cells in the RNAi + RAPA group was lower than that in the other groups. The gene expression of matrix metalloproteinase (MMP)2, MMP‑9 and vascular endothelial growth factor in the RNAi + RAPA group was lower than that in the other experimental groups. In conclusion, RhoC gene silencing combined with RAPA was able to significantly inhibit the growth of hepatocellular carcinoma cells.

Significantly decreased and more variable expression of major CYPs and UGTs in liver microsomes prepared from HBV-positive human hepatocellular carcinoma and matched pericarcinomatous tissues determined using an isotope label-free UPLC-MS/MS method

PURPOSE

To determine the liver expression of cytochrome P450 (CYPs) and uridine 5'-diphosphate-glucuronosyltransferases (UGTs), the major phase I and II metabolism enzymes responsible for clearance and detoxification of drugs, xenobiotic and endogenous substances.

METHODS

A validated isotope label-free method was established for absolute and simultaneous quantification of 9 CYPs (1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D, 2E1 and 3A4) and 5 UGTs (1A1, 1A4, 1A6, 1A9 and 2B7) in human liver microsomes using LC-MS/MS.

RESULTS

The LC-MS/MS method displayed excellent dynamic range (at least 250-fold) and high sensitivity for each of the signature peptides with acceptable recovery, accuracy and precision. The protein expression profile of CYP and UGT isoforms were then determined in match microsomes samples prepared from patients with HBV-positive human hepatocellular carcinoma (HCC). In the tumor microsomes, the average absolute amounts of 8 major CYP isoforms (except CYP2C19) and 3 UGT isoforms (UGT1A1, UGT1A4 and UGT2B7) were decreased significantly (p < 0.05), whereas UGT1A6 and UGT1A9 levels were unchanged (p > 0.05). In addition, among isoforms with altered expression, 6 of 8 CYP isoforms and all three UGT isoforms were much more variable in tumor microsomes. Lastly, the importance of CYP3A4 was greatly diminished whereas the importance of UGT1A6 was enhanced in tumor microsomes.

CONCLUSION

The use of an isotope label-free absolute quantification method for the simultaneous determination of 9 CYPs and 5 UGTs in human liver microsomes reveals that expression levels of CYPs and UGTs in human liver are severely impact by HCC, which could impact drug metabolism, disposition and pharmacotherapy.

RhoGTPases - A novel link between cytoskeleton organization and cisplatin resistance

For more than three decades, platinum compounds have been the first line treatment for a wide spectrum of solid tumors. Yet, cisplatin resistance is a major impediment in cancer therapy, and deciphering the mechanisms underlying chemoresistance is crucial for the development of novel therapies with enhanced efficacy. The Rho subfamily of small GTPases plays a significant role in cancer progression, and a growing body of evidence points toward the involvement of these proteins in anticancer drug resistance, including cisplatin resistance. The cycling between active and inactive states, governed by the balance between their GEFs, GAPs and GDIs, RhoGTPases, acts as molecular switches with a pivotal role in actin cytoskeleton organization. The Rho subfamily of proteins is involved in many key cellular processes including adhesion, vesicular trafficking, proliferation, survival, cell morphology and cell-matrix interactions. Although RhoA, RhoB and RhoC are highly homologous and share some upstream regulators and downstream effectors, they each have different roles in cancer progression and chemoresistance. While RhoA and RhoC are upregulated in many tumors and can stimulate transformation, RhoB appears to exhibit tumor suppressor characteristics with proapoptotic effects. In the current review, we discuss the role of Rho subfamily of proteins in cancer, and focus on their involvement in intrinsic and acquired drug resistance.

Tumor size does not independently affect long-term survival after curative resection of solitary hepatocellular carcinoma without macroscopic vascular invasion

OBJECTIVE

The aim of this study was to investigate the prognostic value of tumor size alone on long-term survival and recurrence after curative resection for solitary hepatocellular carcinoma (HCC) without macroscopic vascular invasion.

METHODS

A single-center cohort of 615 patients with solitary HCC (a single tumor, without macroscopic vascular invasion or distant metastasis) undergoing curative hepatic resection from 2002 to 2010 was retrospectively studied. Using 2.0, 3.0, 4.0, 5.0, 8.0, and 10.0 cm as cut-off values of tumor size, the overall survival (OS) and recurrence-free survival (RFS) rates were compared between the groups of patients with tumor size up to a certain cut-off value and the groups of patients with tumor size above that cut-off value. Thus, multiple comparisons were done. The prognostic factors of OS and RFS were evaluated using univariate and multivariate analyses.

RESULTS

The median tumor size of all HCCs was 4.0 cm (range 0.9-22.0 cm). The in-hospital mortality rate was 1.0 %, and the overall morbidity rate was 22.3 %. The 1-, 3-, and 5-year OS rates were 96.0, 79.8, and 69.9 %, and the corresponding RFS rates were 83.6, 72.7, and 57.2 %, respectively. On univariate analyses, the 1-, 3-, and 5-year OS and RFS rates were significantly different between the individual two groups of patients as divided by the aforementioned different cut-off values of tumor sizes (all p < 0.05). However, when tumor size was put as a continuous variable into multivariate analysis, it was no longer an independent prognostic factor of OS or RFS after curative resection.

CONCLUSIONS

Tumor size did not independently affect long-term survival and recurrence after curative resection of solitary HCC without macroscopic vascular invasion. Therefore, there is no size limit that precludes hepatic resection for solitary HCC, provided the tumor is resectable.

The RhoA pathway mediates MMP-2 and MMP-9-independent invasive behavior in a triple-negative breast cancer cell line

Breast cancer is a heterogeneous disease that varies in its biology and response to therapy. A foremost threat to patients is tumor invasion and metastasis, with the greatest risk among patients diagnosed with triple-negative and/or basal-like breast cancers. A greater understanding of the molecular mechanisms underlying cancer cell spreading is needed as 90% of cancer-associated deaths result from metastasis. We previously demonstrated that the Tamoxifen-selected, MCF-7 derivative, TMX2-28, lacks expression of estrogen receptor α (ERα) and is highly invasive, yet maintains an epithelial morphology. The present study was designed to further characterize TMX2-28 cells and elucidate their invasion mechanism. We found that TMX2-28 cells do not express human epidermal growth factor receptor 2 (HER2) and progesterone receptor (PR), in addition to lacking ERα, making the cells triple-negative. We then determined that TMX2-28 cells lack expression of active matrix metalloproteinases (MMPs)-1, MMP-2, MMP-9, and other genes involved in epithelial-mesenchymal transition (EMT) suggesting that TMX2-28 may not utilize mesenchymal invasion. In contrast, TMX2-28 cells have high expression of Ras Homolog Gene Family Member, A (RhoA), a protein known to play a critical role in amoeboid invasion. Blocking RhoA activity with the RhoA pathway specific inhibitor H-1152, or a RhoA specific siRNA, resulted in inhibition of invasive behavior. Collectively, these results suggest that TMX2-28 breast cancer cells exploit a RhoA-dependent, proteolytic-independent invasion mechanism. Targeting the RhoA pathway in triple-negative, basal-like breast cancers that have a proteolytic-independent invasion mechanism may provide therapeutic strategies for the treatment of patients with increased risk of metastasis.

RhoC upregulation is correlated with reduced E-cadherin in human breast cancer specimens after chemotherapy and in human breast cancer MCF-7 cells

Therapy-resistant cancer cells are a major problem in cancer research. Recent studies suggest that the epithelial-mesenchymal transition (EMT) is a key mechanism in therapy resistance. Yet, the expressions of EMT markers, EMT core regulators, and a stem cell marker of BMI1 during chemotherapy have been poorly analyzed in clinical breast cancer specimens. In the present study, we investigated the roles of RhoC under chemotherapy to follow up on earlier findings demonstrating the involvement of RhoC in prostate cancer resistance to endocrine therapy. Immunohistochemically, E-cadherin expression was significantly lower in human breast cancer specimens analyzed after chemotherapy than specimens biopsied before chemotherapy. Significant upregulation of fibronectin, a mesenchymal EMT marker, was found in post-chemotherapy analysis. A study of the EMT core regulators of SNAIL1, SNAIL2, TWIST1, and a well-known stem cell marker of BMI1 revealed no post-chemotherapy upregulation of these molecules. In contrast, RhoC expression was significantly upregulated in post-chemotherapy breast cancer specimens. MCF-7 cells stably transfected with the constitutive active (CA) RhoC plasmid manifested a reduced level of E-cadherin at the peripheries and disorganization of actin fibers, with no accompanying upregulation of SNAIL1, SNAIL2, TWIST1, or BMI1 in Western blots. Exposure of etoposide on MCF-7 cells showed RhoC upregulation together with reduced membranous expression of E-cadherin and disorganization of actin fibers. In MTT assay, however, the CA-RhoC-expressing MCF-7 cells failed to show chemotherapy resistance under etoposide treatment. Taken in sum, RhoC may contribute to an EMT-like process in human breast cancer during chemotherapy.

Hepatectomy for huge hepatocellular carcinoma: single institute's experience

BACKGROUND

The surgical resection of huge hepatocellular carcinoma (HCC) is still controversial. This study was designed to introduce our experience of liver resection for huge HCC and evaluate the safety and outcomes of hepatectomy for huge HCC.

METHODS

A total of 258 hepatic resections for the patients with huge HCC were analysed retrospectively from December 2002 to December 2011. The operative outcomes were compared with 293 patients with HCC >5.0 cm but <10.0 cm in diameter. Prognostic factors for long-term survival were evaluated by univariate and multivariate analyses.

RESULTS

The 1-, 3-, 5-year overall survival rates after liver resection were 84, 62, and 33 %. Overall survival and disease-free survival in huge HCC group and HCC >5.0 cm but <10.0 cm group were similar (P = 0.751, P = 0.493). Solitary huge HCC group has significantly a more longer overall and disease-free survival time than nodular huge HCC (P = 0.026, P = 0.022). Univariate and multivariate analysis revealed that the types of tumour, vascular invasion, and UICC stage were independent prognostic factors for overall survival (P = 0.047, P = 0.037, P = 0.033).

CONCLUSIONS

Hepatic resection can be performed safely for huge HCC with a low mortality and favorable survival outcomes. Solitary huge HCC has the better surgical outcomes than nodular huge HCC.

Rho GTPases modulate malignant transformation of tumor cells

Rho GTPases are involved in the acquisition of all the hallmarks of cancer, which comprise 6 biological capabilities acquired during the development of human tumors. The hallmarks include proliferative signaling, evading growth suppressors, resisting cell death, enabling replicative immortality, inducing angiogenesis, and activating invasion and metastasis programs, as defined by Hanahan and Weinberg. (1) Controlling these hallmarks are genome instability and inflammation. Emerging hallmarks are reprogramming of energy metabolism and evading immune destruction. To give a different view to the readers, we will not be focusing on invasion, metastasis, or cytoskeletal remodeling, but we will review here how Rho GTPases contribute to other hallmarks of cancer with a special emphasis on malignant transformation.

Rho GTPases and cancer

Rho GTPases are a family of small GTPases, which play an important role in the regulation of the actin cytoskeleton. Not surprisingly, Rho GTPases are crucial for cell migration and therefore highly important for cancer cell invasion and the formation of metastases. In addition, Rho GTPases are involved in growth and survival of tumor cells, in the interaction of tumor cells with their environment, and they are vital for the cancer supporting functions of the tumor stroma. Recent research has significantly improved our understanding of the regulation of Rho GTPase activity, the specificity of Rho GTPases, and their function in tumor stem cells and tumor stroma. This review summarizes these novel findings and tries to define challenging questions for future research.

Up-regulated MicroRNA-181a induces carcinogenesis in hepatitis B virus-related hepatocellular carcinoma by targeting E2F5

Background

Accumulating evidence showed that microRNAs are involved in development and progression of multiple tumors. Recent studies have found that miR-181a were dysregulated in several types of cancers, however, the function of miR-181a in hepatocellular carcinoma (HCC) remains unclear. In this study we assessed the potential association between miR-181a, HBV and HCC.

Methods

The expression of miR-181a in HBV-expressing cells was determined by using qRT-PCR. Dual-Luciferase reporter Assay, qRT-PCR and western blot were performed to investigate the target genes of miR-181a. The effects of miR-181a on HCC proliferation were analyzed by MTS and colony formation assay. Tumor growth assay was used to analyze the effect of miR-181a on tumor formation.

Results

HBV up-regulated miR-181a expression by enhancing its promoter activity. Overexpression of miR-181a in hepatoma cells promoted cell growth in vitro and tumor formation in vivo. Conversely, inhibition of miR-181a suppressed the proliferation of HBV-expressing cells. Mechanism investigation revealed that miR-181a inhibited the expression of transcription factor E2F5 by specifically targeting its mRNA 3′UTR. Moreover, E2F5 inhibition induced cell growth and rescued the suppressive effect of miR-181a inhibitor on the proliferation of SMMC-7721 cells. Interestingly, we also discovered that HBV could down-regulate E2F5 expression.

Conclusions

Those results strongly suggested that HBV down-regulated E2F5 expression, in part, by up-regulating the expression of miR-181a. Up-regulation of miR-181a by HBV in hepatoma cells may contribute to the progression of HCC possibly by targeting E2F5, suggesting miR-181a plays important role in HCC development.

miR-503 regulates metastatic function through Rho guanine nucleotide exchanger factor 19 in hepatocellular carcinoma

BACKGROUND

Our previous work described a metastasis-related microRNAs expression profiling and revealed miR-503 regulating metastatic function in hepatocellular carcinoma (HCC) cells. Here, we investigate to define the mechanism of miR-503 regulating metastasis in HCC.

MATERIALS AND METHODS

The expressions of miR-503 in HCC cell lines and clinical tissues with different metastatic potential were investigated. Meanwhile, a metastatic human HCC cell BALB/c nude mice model was used to investigate whether miR-503 regulates metastasis of HCC in vivo. Furthermore, luciferase activity of reporter gene, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), fluorescence-activated cell sorting analysis (FACS), and invasion assay were carried out to characterize the mechanism of miR-503 regulating metastasis in HCC.

RESULTS

We confirmed the negative correlation between miR-503 expression and metastatic potential of HCC in cell lines and in clinical HCC tissues. We also showed that overexpression of miR-503 resulted in inhibition of proliferation and metastasis of HCC in vivo. Furthermore, we demonstrated that ARHGEF19 is a direct target gene of miR-503. Finally, our results indicated that ARHGEF19 overcomes the suppressive influence of miR-503 in HCC cells.

CONCLUSIONS

Our results suggest an important role of miR-503 in inhibiting metastasis of HCC through deregulating ARHGEF19.

Inhibition of rho-kinase by fasudil suppresses formation and progression of experimental abdominal aortic aneurysms

Objective

Accumulating evidence suggests that inflammatory cell infiltration is crucial pathogenesis during the initiation and progression of abdominal aortic aneurysm (AAA). Given Rho-kinase (ROCK), an important kinase control the actin cytoskeleton, regulates the inflammatory cell infiltration, thus, we investigate the possibility and mechanism of preventing experimental AAA progression via targeting ROCK in mice porcine pancreatic elastase (PPE) model.

Methods and Results

AAA was created in 10-week-old male C57BL/6 mice by transient intraluminal porcine pancreatic elastase infusion into the infrarenal aorta. The mRNA level of RhoA, RhoC, ROCK1 and ROCK2 were elevated in aneurismal aorta. Next, PPE infusion mice were orally administrated with vehicle or ROCK inhibitor (Fasudil at dose of 200 mg/kg/day) during the period of day 1 prior to PPE infusion to day 14 after PPE infusion. PPE infusion mice treated with Fasudil produced significantly smaller aneurysms as compare to PPE infusion mice treated with vehicle. AAAs developed in all vehicle-treated groups within 14 days, whereas AAAs developed in six mice (66%, 6/9) treated with Fasudil within 14 days. Furthermore, our semi-quantitative histological analysis revealed that blood vessels and macrophages were significantly reduced in Fasudil treated mice during the AAA progression. Finally, when mice with existing AAAs were treated with Fasudil, the enlargement was nearly completely suppressed.

Conclusion

Fasudil inhibits experimental AAA progression and stabilize existing aneurysms, through mechanisms likely related to impaired mural macrophage infiltration and angiogenesis. These findings suggest that ROCK inhibitor may hold substantial translational value for AAA diseases.

MicroRNA-140-5p suppresses tumor growth and metastasis by targeting transforming growth factor β receptor 1 and fibroblast growth factor 9 in hepatocellular carcinoma

By comparing the expression profiles of microRNAs (miRNAs) in different hepatocellular carcinoma (HCC) subtypes, we identified miR-140-5p as an HCC-related miRNA. We found that miR-140-5p was significantly decreased in HCC tissues and all of six liver cancer cell lines examined and its expression levels were correlated with multiple nodules, vein invasion, capsular formation, and differentiation, as well as overall and disease-free survival of HCC. We also found that miR-140-5p suppressed HCC cell proliferation and HCC metastasis. Multipathway reporter arrays suggested that miR-140-5p inhibited transforming growth factor β (TGF-β) and mitogen-activated protein kinase / extracellular signal-regulated kinase (MAPK/ERK) signaling. TGFB receptor 1 (TGFBR1) and fibroblast growth factor 9 (FGF9) were then characterized as the direct targets for miR-140-5p after it was found that ectopic miR-140-5p expression suppressed TGFBR1 and FGF9 expression. Silencing TGFBR1 and FGF9 by small interfering RNA (siRNA) resembled the phenotype resulting from ectopic miR-140-5p expression, while overexpression of TGFBR1 and FGF9 attenuated the effect of miR-140-5p on HCC growth and metastasis.

CONCLUSION

These data elucidated a tumor suppressor role for miR-140-5p in HCC development and progression with therapeutic potential. Our correlation studies in clinical HCC samples further suggest that miR-140-5p could be a valuable biomarker for HCC prognosis.

Overexpression of human telomerase reverse transcriptase promotes the motility and invasiveness of HepG2 cells in vitro

Recent studies have indicated that telomerase activity promotes cancer invasion and metastasis, but the underlying mechanism remains unclear. Several studies have shown that expression of exogenous human telomerase reverse transcriptase (hTERT) can promote motility and invasiveness among telomerase-negative tumor cells, and inhibition of endogenous telomerase activity can reduce invasiveness in tumor cells. However, whether overexpression of hTERT can further enhance the motility and invasiveness of telomerase‑positive tumor cells has yet to be determined. In the present study, we showed that stable overexpression of hTERT can increase telomerase activity and telomere length, which significantly promotes the invasive and metastatic potential of telomerase‑positive HepG2 cells but does not affect cell proliferation. Further analysis suggested that enhanced invasiveness and metastasis may act through corresponding upregulation of mRNA and protein expression of matrix metalloproteinase 9 (MMP9) and Ras homolog gene family member C (RhoC). Our study indicated that exogenous expression of hTERT may promote invasiveness and metastasis through upregulation of MMP9 and RhoC.

Diverse roles for the paxillin family of proteins in cancer

The paxillin family of intracellular scaffold proteins includes paxillin, Hic-5, and leupaxin, and all have been identified as key regulators of the cellular migration machinery in both 2- and 3-dimensional microenvironments. Herein, we provide insight into the roles of these proteins during tumorigenesis and metastasis, highlighting their functions in cancer initiation as well as tumor cell dissemination and survival. Furthermore, we speculate on the potential of paxillin family proteins as both future prognostic and therapeutic targets.

Potential for statins in the chemoprevention and management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a common, treatment-resistant malignancy with a complex molecular pathogenesis. Statins are a widely used class of cholesterol-lowering drugs with potential anticancer activity. We reviewed the evidence for a role of statins in primary and secondary chemoprevention of HCC and slowing the course of otherwise incurable primary or recurrent disease. A literature search (key words: Statins, hepatocellular carcinoma) conducted to this end, retrieved 119 references. Here we summarize the history, mechanism of action and cardiovascular use of statins and highlight that statins can affect several pathways implicated in the development of HCC. In vitro and animal studies provide strong evidence for a favorable effect of statins on HCC. However, evidence in humans is conflicting. We discuss in full detail the methodological strengths and pitfalls of published data including three cohort studies suggesting that the use of statins may protect from the development of HCC and of a single trial reporting increased survival in those with advanced HCC randomized to receive statins. A remarkably hepato-safe class of drugs acting on both hepatocyte and endothelial cells, statins also have potentially beneficial effects in lowering portal hypertension. In conclusion, there is strong experimental evidence that statins are beneficial in chemopreventing and slowing the growth of HCC. However, randomized controlled trials are necessary in order to investigate the role of statins in the chemoprevention of HCC and in slowing the course of otherwise incurable disease in humans.

Novel roles of Vmp1: inhibition metastasis and proliferation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most deadly human cancers because of its high incidence of metastasis. Despite extensive efforts, therapies against metastasis of HCC remain underdeveloped. Vacuole membrane protein 1 (Vmp1) was recently identified to be involved in cancer-relevant processes; however, its expression, clinical significance and biological function in HCC progression are still unknown. Therefore, we evaluated the expression of Vmp1 in human HCC specimens. To functionally characterize Vmp1 in HCC, we upregulated its expression in HCCLM3 cells using a plasmid transfection approach, following which both in vitro and in vivo models were used to elucidate its role. A significant downregulation of Vmp1 was found in human HCC tissues and closely correlated with multiple tumor nodes, absence of capsular formation, vein invasion and poor prognosis of HCC. Such expression was verified with HCC cell lines including HepG2, MHCC97-L and HCCLM3, and the Vmp1 expression levels negatively correlated with metastatic potential. Interestingly, upregulation of Vmp1 significantly affects proliferation, migration, invasion and adhesion of HCCLM3 cells. Using a mouse model, we demonstrated that upregulation of Vmp1 was associated with suppression of growth and pulmonary metastases of HCC. Therefore, our data suggest Vmp1 is a novel prognostic marker and potential therapeutic target for metastasis of HCC.

Cyclin A2, Rho GTPases and EMT

Cell cycle regulators, such as cyclins, are often upregulated in many proliferative disorders, and Cyclin A2 is generally considered as a marker of aggressive cancers. Our recent work, which revealed decreased expression of Cyclin A2 upon metastasis of colorectal cancer, suggests a more complicated situation. Consistent with this, we identified a role for Cyclin A2, via RhoA, in regulation of the actin cytoskeleton and the control of cell invasion. Cyclin A2 also regulates spindle orientation which, when misoriented, could disrupt cell polarity and favor cancer cell detachment from the tumor as part of a transforming process, such as epithelial to mesenchymal transition (EMT). During EMT, cells undergo morphological and molecular changes toward a mesenchymal phenotype. Upregulation, or increased activity of some Rho GTPases, such as Cdc42, Rac1 or RhoC, increases the invasive potential of these cells. This correlates with the inverse relationship between RhoA and RhoC activities we observed in an epithelial cell type. Altogether, these observations raise the possibility that Cyclin A2 is instrumental in preventing EMT and therefore cancers of epithelial tissues.

Analysis of the risk factors for early death due to disease recurrence or progression within 1 year after hepatectomy in patients with hepatocellular carcinoma

Background

Liver resection for hepatocellular carcinoma (HCC) has the highest local controllability among all local treatments and results in a good survival rate. However, the recurrence rates of HCC continue to remain high even after curative hepatectomy Moreover, it has been reported that some patients with HCC have an early death due to recurrence. We analyzed the preoperative risk factors for early cancer death.

Methods

Between 1997 and 2009, 521 consecutive patients who underwent hepatectomy for HCC at our center were assigned to group ED (death due to HCC recurrence or progression within 1 year after hepatectomy) and group NED (alive over 1 year after hepatectomy). Risk factors for early cancer death were analyzed.

Results

Group ED included 48 patients, and group NED included 473 patients. The cause of death included cancer progression (150; 78.1%), operation-related (1; 0.5%), hepatic failure (15; 7.8%), and other (26; 13.5%). Between the ED and NED groups, there were significant differences in albumin levels, Child-Pugh classifications, anatomical resections, curability, tumor numbers, tumor sizes, macroscopic vascular invasion (portal vein and hepatic vein), alpha-fetoprotein (AFP) levels, AFP-L3 levels, protein induced by vitamin K absence or antagonism factor II (PIVKA-II) levels, differentiation, microscopic portal vein invasion, microscopic hepatic vein invasion, and distant metastasis by univariate analysis. Multivariate analysis identified specific risk factors, such as AFP level > 1,000 ng/ml, tumor number ≥ 4, tumor size ≥ 5 cm, poor differentiation, and portal vein invasion. With respect to the preoperative risk factors such as AFP level, tumor number, and tumor size, 3 (1.1%) of 280 patients with no risk factors, 12 (7.8%) of 153 patients with 1 risk factor, 24 (32.9%) of 73 patients with 2 factors, and 9 (60.0%) of 15 patients with 3 risk factors died within 1 year of hepatectomy (p < 0.0001).

Conclusions

Hepatectomy should be judiciously selected for patients with AFP level > 1,000 ng/ml, tumor number ≥ 4, and tumor size ≥ 5 cm, because patients with these preoperative risk factors tend to die within 1 year after hepatectomy; these patients might be better treated with other therapy.

The interaction of PKN3 with RhoC promotes malignant growth

PKN3 is an AGC-family protein kinase implicated in growth of metastatic prostate cancer cells with phosphoinositide 3-kinase pathway deregulation. The molecular mechanism, however, by which PKN3 contributes to malignant growth and tumorigenesis is not well understood. Using orthotopic mouse tumor models, we now show that inducible knockdown of PKN3 protein not only blocks metastasis, but also impairs primary prostate and breast tumor growth. Correspondingly, overexpression of exogenous PKN3 in breast cancer cells further increases their malignant behavior and invasiveness in-vitro. Mechanistically, we demonstrate that PKN3 physically interacts with Rho-family GTPases, and preferentially with RhoC, a known mediator of tumor invasion and metastasis in epithelial cancers. Likewise, RhoC predominantly associates with PKN3 compared to its closely related PKN family members. Unlike the majority of Rho GTPases and PKN molecules, which are ubiquitously expressed, both PKN3 and RhoC show limited expression in normal tissues and become upregulated in late-stage malignancies. Since PKN3 catalytic activity is increased in the presence of Rho GTPases, the co-expression and preferential interaction of PKN3 and RhoC in tumor cells are functionally relevant. Our findings provide novel insight into the regulation and function of PKN3 and suggest that the PKN3-RhoC complex represents an attractive therapeutic target in late-stage malignancies.

Tumor suppressor microRNA-493 decreases cell motility and migration ability in human bladder cancer cells by downregulating RhoC and FZD4

The purpose of this study was to identify new tumor suppressor microRNAs (miRNA; miR) in bladder cancer, conduct functional analysis of their suppressive role, and identify their specific target genes. To explore tumor suppressor miRs in bladder cancer, miR microarray was conducted using SV-HUC-1, T24, J82, and TCCSUP cells. Expression of miR-493 in bladder cancer (T24, J82, and TCCSUP) cells was downregulated compared with normal SV-HUC-1 cells. Also, the expression of miR-493 was significantly lower in bladder cancer tissues than in their corresponding noncancerous tissues. Transfection of miR-493 into T24 or J82 cells decreased their cell growth and migration abilities. On the basis of this result, to identify potential miR-493 target genes, we used target scan algorithms to identify target oncogenes related to invasion and migration. miR-493 decreased 3'-untranslated region luciferase activity and protein expression of FZD4 and RhoC. miR-493 also decreased binding of RhoC and Rock-1. miR-493 is a new tumor suppressor miRNA in bladder cancer and inhibits cell motility through downregulation of RhoC and FZD4.

Expression of claudin 10 protein in hepatocellular carcinoma: impact on survival

PURPOSE

To investigate the expression of claudin 10 in hepatocellular carcinoma (HCC) and the impact on angiogenesis and the postoperative survival of HCC patients.

METHODS

The expression of claudin 10 protein was analyzed on samples from 99 HCC patients undergoing hepatectomy with immunohistochemistry and 31 fresh specimens with Western blotting. We examined the relationship between claudin 10 expression with clinicopathological factors, microvessel density (MVD), and postoperative survival.

RESULTS

Western blotting and immunohistochemical staining showed that claudin 10 protein was highly expressed in HCC, compared with paraneoplastic liver tissue and normal liver tissue (P < 0.01). Claudin 10 protein expression levels were significantly higher in HCC specimens with microscopic venous invasion (P < 0.01). MVD in HCC increased with enhanced claudin 10 expression (P < 0.01). Kaplan-Meier survival analysis revealed that HCC patients with high claudin 10 expression had significantly shorter overall survival (P = 0.01). Multivariate analysis showed that claudin 10 expression was an independent prognostic indicator for postoperative overall survival of HCC patients (P < 0.01).

CONCLUSIONS

Claudin 10 protein is highly expressed in HCC tissue and is closely related to angiogenesis. Claudin 10 protein could be a useful marker to predict poor prognosis of HCC patients after hepatectomy.

RhoGDIα-dependent balance between RhoA and RhoC is a key regulator of cancer cell tumorigenesis

RhoGTPases are key signaling molecules regulating main cellular functions such as migration, proliferation, survival, and gene expression through interactions with various effectors. Within the RhoA-related subclass, RhoA and RhoC contribute to several steps of tumor growth, and the regulation of their expression affects cancer progression. Our aim is to investigate their respective contributions to the acquisition of an invasive phenotype by using models of reduced or forced expression. The silencing of RhoC, but not of RhoA, increased the expression of genes encoding tumor suppressors, such as nonsteroidal anti-inflammatory drug-activated gene 1 (NAG-1), and decreased migration and the anchorage-independent growth in vitro. In vivo, RhoC small interfering RNA (siRhoC) impaired tumor growth. Of interest, the simultaneous knockdown of RhoC and NAG-1 repressed most of the siRhoC-related effects, demonstrating the central role of NAG-1. In addition of being induced by RhoC silencing, NAG-1 was also largely up-regulated in cells overexpressing RhoA. The silencing of RhoGDP dissociation inhibitor α (RhoGDIα) and the overexpression of a RhoA mutant unable to bind RhoGDIα suggested that the effect of RhoC silencing is indirect and results from the up-regulation of the RhoA level through competition for RhoGDIα. This study demonstrates the dynamic balance inside the RhoGTPase network and illustrates its biological relevance in cancer progression.