miRNA-135a promotes hepatocellular carcinoma cell migration and invasion by targeting forkhead box O1.

AIMS: Hepatocellular carcinoma (HCC) is the third leading cause of cancer mortality worldwide. Many microRNAs (miRNAs), small non-coding RNAs, are involved in regulating cancer cell proliferation, metastasis, migration, invasion and apoptosis. MAIN METHODS: We investigated the expression of miR-135a in HCC cell lines and clinical tissues. The effect of miR-135a on migration and invasion of HepG2 and MHCC-97L were examined using wound healing and Transwell assay. We determined the expression of miR-135a, forkhead box O1 (FOXO1), matrix metalloproteinase-2 (MMP-2) and Snail using real-time PCR and western blotting. KEY FINDINGS: We found miR-135a was upregulated in HCC cell lines and tissues. miR-135a overexpression promoted HCC cells migration and invasion, whereas miR-135a inhibition suppressed HCC cells migration and invasion. miR-135a overexpression could upregulate the expression of MMP2, Snail and the phosphorylation of AKT, but decreased FOXO3a phosporylation. Tumor suppressor FOXO1 was the direct target for miR-135a. SIGNIFICANCE: Our results suggested that miR-135a might play an important role in promoting migration and invasion in HCC and presents a novel mechanism of miRNA-mediated direct suppression of FOXO1 in HCC cells.

MiR-501-5p regulates CYLD expression and promotes cell proliferation in human hepatocellular carcinoma.

OBJECTIVE: Previous studies have shown that the micro-ribonucleic acid miR-501-5p is upregulated in hepatocellular carcinoma cells and tissues with high hepatitis B virus replication, and that miR-501 overexpression significantly promotes hepatitis B virus replication. We further analysed a published microarray-based high-throughput dataset (NCBI/GEO/GSE36915) and found that miR-501-5p was upregulated in hepatocellular carcinoma tumour tissues. We therefore investigated the possible function of miR-501-5p during the development of hepatocellular carcinoma. METHODS: Expression of miR-501-5p in human hepatocellular carcinoma specimens and cell lines was assessed, using real-time polymerase chain reaction. Luciferase reporter assays were used to confirm CYLD as a target of miR-501-5p. The effect of miR-501-5p on cell proliferation was confirmed, using tetrazolium and colony formation assays. Gene and protein expression were examined, using real-time polymerase chain reaction and western blotting, respectively. RESULTS: MiR-501-5p was upregulated in hepatocellular carcinoma specimens and cell lines, and directly targeted the 3' untranslated region of CYLD. MiR-501-5p upregulation corresponded with a downregulation of CYLD in the same tissues and cell lines, and overexpression of MiR-501-5p decreased CYLD expression, increased expression of cyclin D1 and c-myc and promoted the proliferation of hepatocellular carcinoma cells in vitro. CONCLUSIONS: This study suggests that miR-501-5p may play an important role in the development of hepatocellular carcinoma by promoting cell proliferation, and indicates that miR-501-5p may represent a novel therapeutic target for hepatocellular carcinoma.

miR-630 overexpression in hepatocellular carcinoma tissues is positively correlated with alpha-fetoprotein.

BACKGROUND: MicroRNA-630 (miR-630) has been shown to be involved in various human malignancies. However, its role in hepatocellular carcinoma (HCC) remains unknown. MATERIAL AND METHODS: TaqMan qRT-PCR assay was performed to detect the expression of miR-630 in 42 pairs of HCC tissues and corresponding noncancerous hepatocellular tissues, and its correlations with clinicopathologic features and serum alpha-fetoprotein (AFP) level of patients were analyzed. RESULTS: The present study found that miR-630 expression was significantly increased in HCC tissues and cells compared with their normal counterparts. miR-630 expression level did not significantly chang at stage I but was markedly increased at advanced TNM stage (stage II~III). In addition, the increased expression of miR-630 in tissues of HCC appeared in patients who exhibited elevated serum levels of AFP (>25 ng/ml), but not in those with normal AFP levels (≤25 ng/ml). The miR-630 expression in carcinoma tissues revealed a positive correlation with the levels of serum alpha-fetoprotein (AFP; R2=0.768). CONCLUSIONS: These results suggest that miR-630 is associated with tumor progression of hepatocellular carcinoma and may be a potential prognosis indicator.

Downregulation of miR-610 promotes proliferation and tumorigenicity and activates Wnt/ß-catenin signaling in human hepatocellular carcinoma.

BACKGROUND: Wnt/ß-catenin signaling pathway plays important roles in human cancer progression. Better understanding the mechanism underlying regulation of Wnt/ß-catenin signaling pathway might provide novel therapeutic targets for cancer treatment. METHODS: miR-610 expression levels in hepatocellular carcinoma (HCC) cell lines, HCC tissues and 76 archived HCC specimens were determined using real-time PCR. Cell viability was measured by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. The level of DNA synthesis was determined by BrdU incorporation assay. Flow cytometry analysis was used to analyze cell cycle progression. The cells proliferation and tumorigenesis were determined by colony formation and anchorage-independent growth assays in vitro, and by xenograft tumors in vivo. Luciferase assay and micro-ribonucleoprotein complex immunoprecipitation assay were used to confirm the association of the targeted mRNAs with miR-610. RESULTS: miR-610 was downregulated in human HCC cells and tissues, and correlated with HCC progression and patient survival. Inhibition of miR-610 promoted, but overexpression of miR-610 reduced, HCC cell proliferation and tumorigenicity both in vitro and in vivo. Furthermore, we found that inhibiting miR-610 activated, but overexpressing miR-610 decreased, the Wnt/ß-catenin activity through directly suppressing lipoprotein receptor-related protein 6 (LRP6) and transducin ß-like protein 1 (TBL1X). The in vitro analysis was consistent with the inverse correlation detected between miR-610 levels with expression of LRP6 and TBL1X in a cohort of human HCC samples. CONCLUSIONS: Our results indicate that miR-610 downregulation plays essential roles in HCC progression and reduced miR-610 is correlated with Wnt/ß-catenin signaling pathway.

LIM protein JUB promotes epithelial-mesenchymal transition in colorectal cancer.

Metastasis is the leading cause of cancer-related death in almost all types of cancers, including colorectal cancer (CRC). Metastasis is a complex, multistep, dynamic biological event, and epithelial-mesenchymal transition (EMT) is a critical process during the cascade. Ajuba family proteins are LIM domain-containing proteins and are reported to be transcription repressors regulating different kinds of physiological processes. However, the expression and pathological roles of Ajuba family proteins in tumors, especial in tumor metastasis, remain poorly studied. Here, we found that JUB, but not the other Ajuba family proteins, was highly upregulated in clinical specimens and CRC cell lines. Ectopic expression of JUB induced EMT and enhanced motility and invasiveness in CRC, and vice versa. Mechanistic study revealed that JUB induces EMT via Snail and JUB is also required for Snail-induced EMT. The expression of JUB shows an inverse correlation with E-cadherin expression in clinical specimens. Taken together, these findings revealed that the LIM protein JUB serves as a tumor-promoting gene in CRC by promoting EMT, a critical process of metastasis. Thus, the LIM protein JUB may provide a novel target for therapy of metastatic CRC.

miR-451 inhibits cell proliferation in human hepatocellular carcinoma through direct suppression of IKK-ß.

It has been demonstrated that nuclear factor-kappa B (NF-κB), which is overactivated in hepatocellular carcinoma (HCC), plays important roles in the development of HCC. Recently, a group of dysregulated micro RNAs were reported to be involved in HCC progression. Further understanding of micro RNA-mediated regulation of NF-κB pathway may provide novel therapeutic targets for HCC. In this study, we found that miR-451 expression was markedly downregulated in HCC cells and tissues compared with immortalized normal liver epithelial cells and adjacent non- cancerous tissues, respectively. Upregulation of miR-451 inhibited, while downregulation of miR-451 promoted, the tumorigenicity of HCC cells both in vitro and in vivo. These changes in the properties of HCC cells were associated with deregulation of two well-known cellular G1/S transitional regulators, cyclin D1 and c-Myc, which are downstream targets of NF-κB pathway. Furthermore, we demonstrated that miR-451 upregulation led to downregulation of cyclin D1 and c-Myc through inhibition of NF-κB pathway initiated by direct targeting of the IKBKB 3'-untranslated region. Therefore, these results suggest that miR-451 downregulation plays an important role in promoting proliferation of HCC cells and may provide the basis for the development of novel anti-HCC therapies.

Upregulation of CPE promotes cell proliferation and tumorigenicity in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is one of the most common cancers worldwide and a leading cause of cancer related death. Although the mortality rate of CRC is decreasing, finding novel targets for its therapy remains urgent. Carboxypeptidase E (CPE), a member of the pro-protein convertases, which are involved in the maturation of protein precursors, has recently been reported as elevated in many types of cancer. However, its role and mechanisms in tumor progression are poorly understood. METHODS: In the present study, we investigated expression of CPE in CRC cell lines and tumor tissues using Western blot and real-time qRT-PCR. Plasmids for overexpression and depletion of CPE were constructed and analyzed by Western blot, MTT and colony formation assays and bromodeoxyuridine incorporation assays. The relative expression of p21, p27, and cyclin D1 were analyzed by Real-time qRT-PCR in the indicated cells. RESULTS: Our study showed that CPE was significantly upregulated in CRC cell lines and tumor tissues. MTT and colony formation assays indicated that overexpression of CPE enhanced cell growth rates. BrdU incorporation and flow-cytometry assays showed that ectopic expression of CPE increased the S-phase fraction cells. Soft agar assay proved enhanced tumorigenicity activity in CPE over-expressing CRC cells. Further studies of the molecular mechanisms of CPE indicated that is promoted cell proliferation and tumorigenicity through downregulation of p21 and p27, and upregulation of cyclin D1. CONCLUSIONS: Taken together, these data suggest that CPE plays an important role in cell cycle regulation and tumorigenicity, and may serve as a potential target for CRC therapeutics.

Chemoembolization with lobaplatin mixed with iodized oil for unresectable recurrent hepatocellular carcinoma after orthotopic liver transplantation.

PURPOSE: To determine whether chemoembolization can benefit patients with unresectable recurrent hepatocellular carcinoma (HCC) after orthotopic liver transplantation (OLT). MATERIALS AND METHODS: Twenty-eight of 71 patients (39%) with unresectable recurrent HCC following OLT and without contradictions to chemoembolization were included: 14 patients received chemoembolization after OLT (chemoembolization group) and 14 matched control subjects who did not receive chemoembolization (non-chemoembolization group). Tumor response was determined with follow-up computed tomography after each chemoembolization procedure and classified into four grades according to Response Evaluation Criteria in Solid Tumors. Overall survival was evaluated from OLT and from the diagnosis of recurrent HCC. RESULTS: Within a median follow-up of 14.5-months, 12 of the 14 patients in the chemoembolization group (86%) and 13 of the 14 in the non-chemoembolization group (93%) developed new recurrences. Eight of the 14 patients in the chemoembolization group (57%) showed partial tumor response (>30% reduction in the size of target lesions). Moreover, patients who underwent chemoembolization had a significantly longer overall survival after OLT (P = .0133) and after the diagnosis of HCC recurrence (P = .0338) compared to those who did not. No severe complications developed in patients receiving chemoembolization during follow-up. CONCLUSIONS: Lobaplatin-based chemoembolization may elicit effective tumor response for recurrent HCCs and improve the overall survival of patients with unresectable HCC recurrence following OLT.

[Retransplantation for hepatic artery complications after orthotopic liver transplantation].

OBJECTIVE: To evaluate the efficacy and timing of re-transplantation for hepatic artery complications after orthotopic liver transplantation. METHODS: Between December 2003 and December 2006, the clinical data of 13 patients diagnosed as hepatic artery complications after liver transplantation were retrospectively analyzed. RESULTS: There were no significant difference in duration of operation and anhepatic phase between the initial transplantation and the second transplantation (P = 0.291, P = 0.312). However, intra-operative blood loss [(3.1 +/- 1.1) L vs. (1.5 +/- 0.9) L, P = 0.005] and intensive care unit stays [(4.3 +/- 1.8) d vs. (3.2 +/- 2.5) d, P = 0.015] were significantly increased in the re-transplant patients. No perioperative mortality occurred. The postoperative mortality of liver re-transplantation was 38.5% (5/13) including acute renal failure in two patients, severe infection in two and heart infarction in one. The other 8 patients were followed from 6 months to 51 months, with a median survival time of 22.5 months. CONCLUSIONS: Liver re-transplantation is the only viable option for patients with irreversible graft dysfunction secondary to hepatic artery complications after liver transplantation. Proper indication and optimum time of re-transplantation, reasonable individual immunosuppression regime and effective perioperative care program contribute to the increase of the survival rate of the patients performed liver re-transplantation.

Down-regulation of microRNA-338-3p promoted angiogenesis in hepatocellular carcinoma.

miRNAs are involved in substantial biological passways, including tumorigenesis, cancer development and progression. Angiogenesis plays a vital role in the progression of hepatocellular carcinoma (HCC), and VEGF is closely associated with the angiogenesis. However, the molecular mechanism of miRNAs in regulation tumorigenesis of HCC remains to be investigated. In the present research, we confirmed that miR-338-3p was suppressed both in HCC tissues and HCC cell lines. Then the tube formation, transwell and Chorioallantoic membrane (CAM) assay were carried out, such indicated that down-regulation of miR-338-3p can sharply increased, while up-regulation drastically suppressed angiogenesis of HCC cells in vitro. Moreover, MACC1 is predicted to be a target of miR-338-3p and we checked the prediction through luciferase assay. And then, our research showed that negative correlation existed between miR-338-3p and MACC1, ß-catenin and VEGF that has been reported participated in cancer behavior in HCC cell lines. Subsequently, our assays illustrated that suppression miR-338-3p can up-regulate MACC1, ß-catenin and VEGF expression of HCC cells. In conclusion, our research discovered that miR-338-3p can contribute to HCC angiogenesis by targeting MACC1, ß-catenin and VEGF.

Aberrantly regulated dysadherin and B-cell lymphoma 2/B-cell lymphoma 2-associated X enhances tumorigenesis and DNA targeting drug resistance of liver cancer stem cells.

Cancer stem cells (CSCs) in hepatocellular carcinoma (HCC) are frequently resistant to current therapeutic regimens and therefore responsible for tumor recurrence. Previous studies have reported that expression levels of dysadherin in CSCs may be used as a prognostic indicator, which is also responsible for treatment failure and poor survival rates. The present study analyzed the association of enhanced dysadherin levels with drug resistance and evasion of apoptosis in human HCC SP cells. An SP of 3.7% was isolated from human HCC cells using fluorescence­activated cell sorting. These SP cells displayed elevated levels of dysadherin and stemness proteins as well as high resistance to chemotherapeutic drugs and apoptosis. In order to reveal the possible link between dysadherin levels and tumorigenesis of SP cells, small interfering RNA technology was used to knockdown the expression of dysadherin in SP cells. Of note, the siRNA­transfected SP cells showed significantly reduced levels of stemness proteins, and were more sensitive to DNA­targeting drugs and apoptotic cell death as compared to non­transfected cells. Furthermore, in vivo experiments in NON/SCID mice indicated that dysadherin­expressing SP cells were highly tumorigenic, as they were able to induce tumor growth. The SP cell­derived tumor tissues in turn showed elevated dysadherin levels. The results of the present study therefore suggested that knockdown of dysadherin suppressed the tumorigenic properties of cancer stem-like SP cells. Hence, dysadherin is a valuable potential target for the development of novel anti-cancer drugs.

Prostate tumor overexpressed 1 is a novel prognostic marker for hepatocellular carcinoma progression and overall patient survival.

The gene prostate tumor overexpressed 1 (PTOV1) was first found to be upregulated in prostate cancer. This upregulation increased tumor cell proliferation, retinoic acid resistance, and migration. This study investigated the expression and prognostic significance of PTOV1 in hepatocellular carcinoma (HCC). Real-time Polymerase Chain Reaction and western blot analysis were performed to examine PTOV1 expression in 11 HCC cell lines and 2 normal hepatic cell lines. PTOV1 expression levels were also determined in 8 pairs of tissue samples taken from primary HCC tumors and the matched adjacent noncancerous liver tissue from the same patient. Immunohistochemistry assays assessed PTOV1 protein expression in paraffin-embedded clinical samples taken from 215 HCC patients. The correlation of PTOV1 expression with the clinicopathological parameters was evaluated along with the prognostic impact of PTOV1 expression in these HCC patients. PTOV1 mRNA and protein were overexpressed in HCC cell lines compared with normal liver cell lines and were overexpressed in primary HCC samples compared with the matched noncancerous liver tissue samples. In the paraffin-embedded tissue samples from 215 HCC patients, PTOV1 protein expression was significantly correlated with T classification, N classification, clinical stage, and serum α-fetoprotein. HCC patients with higher PTOV1 expression had shorter survival times than patients with lower PTOV1 expression. Our study demonstrated that PTOV1 overexpression is correlated with increased aggressiveness of HCC and could be a prognostic biomarker for patients with HCC.

Downregulation of miR-432 activates Wnt/ß-catenin signaling and promotes human hepatocellular carcinoma proliferation.

Sustained cell growth and proliferation, one of the hallmarks of cancer, is considered to responsible for cancer-related deaths by disorganizing the balance of growth promotion and growth limitation. Aberrant activation of the Wnt/ß-catenin signaling pathway leads to cell proliferation, growth and survival, and promotes the development of various human tumors, including hepatocellular carcinoma. Elucidating the molecular mechanism of this abnormality in hepatocellular carcinoma carcinogenesis may improve diagnostic and therapeutic strategies for this malignancy. Herein, we report that the expression of miR-432 was markedly downregulated in hepatocellular carcinoma cell lines and tissues, and upregulation of miR-432 inhibited, whereas downregulation of miR-432 enhanced the proliferation and tumorigenicity of hepatocellular carcinoma cells both in vitro and in vivo. Furthermore, miR-432 directly targeted and suppressed multiple regulators of the Wnt/ß-catenin signaling cascade, including LRP6, TRIM29 and Pygo2, which subsequently deactivated Wnt/ß-catenin signaling pathway. Finally, miR-432 expression was inversely correlated with three targets in clinical hepatocellular carcinoma samples. These results demonstrated that miR-432 functions as a tumor-suppressive miRNA by suppressing Wnt/ß-catenin signaling activation and may represent a therapeutic target for hepatocellular carcinoma.

Mimic models of peroxidase--kinetic studies of the catalytic oxidation of hydroquinone by H2O2.

The reactions of hydroquinone with hydrogen peroxide catalyzed by transition metal ions Cu2+, Fe2+, Fe3+, Co2+ and Mn2+ were investigated in aqueous solution at 25 degrees C. Two copper (II) complexes (bis(dimethylglyoxime) copper(II) and 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-dienatocopper(II)iodide) were prepared. Their catalytic activities on this oxidation were kinetically investigated in aqueous solution and in cetyltrimethylammonium bromide (CTAB) micellar solution at 25 degrees C. The kinetic equations for micellar catalysis and metallomicellar catalysis were established, respectively. CTAB micelle enhances the reaction rate due to its concentrated and electrostatic effects on substrates and/or intermediate. Metallomicelle exhibits remarkable catalytic activity on this oxidation reaction, which is attributed to the active center and the microenvironment effects. Metallomicelle enhances the rate of reaction by activating hydroquinone anion. The presence of co-ligand of imidazole (or pyridine) remarkably increases the catalytic activity of metal complex in micelle system in contrast to it lowers the activity of the complex in aqueous solution. Metallomicelles could be treated as the mimic models of peroxidase.

Mir-184 post-transcriptionally regulates SOX7 expression and promotes cell proliferation in human hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common human malignancies and the third leading cause of cancer mortality worldwide. The development and progression of HCC is a complicated process, involving the deregulation of multiple genes that are essential to cell biological processes. Recently, microRNAs (miRNAs) have been suggested to be closely associated with tumorigenesis. Our study showed that miR-184 is upregulated in HCC cell lines and tissues. Overexpression of miR-184 in HCC cells increased cell proliferation, tumorigenicity, and cell cycle progression, whereas inhibition of miR-184 reduced cell proliferation, tumorigenicity, and cell cycle progression. Additionally, we identified SOX7 as a direct target of miR-184. Ectopic expression of miR-184 led to downregulation of the SOX7 protein, resulting in upregulation of c-Myc, Cyclin D1, and phosphorylation of Rb. Our findings suggested that miR-184 represents a potential onco-miR and plays an important role in HCC progression by suppressing SOX7 expression.

Differential expression of stromal aromatase in obese females is regulated by DNA methylation.

Obesity increases the incidence, progression and mortality of breast cancer among postmenopausal females. This is partly due to excessive estrogen production in the adipose tissue of obese females. Aromatase is a key enzyme in estrogen biosynthesis. In the current study, the tensional force­triggered inducibility of aromatase expression was observed to vary in ASCs isolated from different disease­free individuals. In addition, this phenomenon was associated with the activation of the aromatase PII promoter and its DNA methylation load. These findings highlight the impact of tensional forces on estrogen biosynthesis in obese females.

RNA interfering targeting human leukocyte antigen-G enhanced immune surveillance mediated by the natural killer cells on hepatocellular carcinoma.

BACKGROUND: Up-regulation of Human Leukocyte Antigen-G (HLA-G) expression is thought to contribute to the escape in immune surveillance by suppressing natural killer (NK) cell function. However, little is known about the expression of HLA-G in hepatocellular carcinoma (HCC) and its relationship to NK cell-mediated cytotoxicity. In this study, we aimed to investigate the expression of HLA-G in human HCC cell lines and determine whether its expression was related to inhibition of NK cell cytolysis. MATERIALS AND METHODS: The levels of HLA-G gene expression in human HCC cell lines were assessed by indirect immunofluorescence analysis (IFA), Real time RT-PCR and Western Blot. Vectors containing small interfering RNA (siRNA) specifically targeting the HLA-G gene were constructed and applied to diminish HLA-G expression. The cells were examined by flow cytometry and fluorescent microscope 24 h after transfection as well as 2-3 weeks after G418 selection. The steady-state levels of HLA-G mRNA and protein were then checked by real time RT-PCR and Western Blot analysis, respectively. A nonradioactive cytotoxicity assay was used to evaluate the effect of HLA-G on NK-mediated cytotoxicity against the siRNA treated cells. RESULTS: Both HLA-G mRNA and protein can be detected in human HCC cell lines. Levels of HLA-G mRNA and protein were diminished 88.73% and 75.91% respectively by targeting siRNA. In the stable HLA-G gene knock-down cell lines, a significant increase in NK cell-mediated lysis occurred. CONCLUSIONS: Abnormal expression of HLA-G in HCC cell lines plays an important role in protecting against NK cell attack. The significant correlation between HLA-G expression and NK cell lysis implies that the abnormal expression of HLA-G might contribute to the mechanism of escape from host immune surveillance in HCC.