MicroRNAs dysregulation in hepatocellular carcinoma: Insights in genomic medicine

Establishment and Validation of a Blood Test-based Nomogram to Diagnose Patients with AFP-negative HCC

BACKGROUND

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer death worldwide. Alpha-protein (AFP) is the most widely used blood biomarker for HCC. However, elevated serum AFP is only observed in part of HCC.

AIMS

This study aimed to develop an efficient nomogram model to distinguish patients with alpha- protein-negative HCC and liver cirrhosis.

OBJECTIVES

A total of 1130 patients (508 HCC patients + 622 cirrhosis patients) were enrolled in the training cohort. A total of 244 HCC patients and 246 cirrhosis patients were enrolled in the validation cohort.

METHODS

A total of 41 parameters about blood tests were analyzed with logistic regression. The nomogram was based on independent factors and validated both internally and externally.

RESULTS

Independent factors were eosinophils %, hemoglobin concentration distribution width, fibrinogen, platelet counts, total bile acid, and mitochondria aspartate aminotransferase. The calibration curve for the probability of HCC showed good agreement between prediction by nomogram and actual observation. The concordance index was 0.851. In the validation cohort, the nomogram distinguished HCC from liver cirrhosis with an area under the curve of receiver operating characteristic of 0.754.

CONCLUSION

This proposed nomogram was an accurate and useful method to distinguish patients with AFP-negative HCC from liver cirrhosis.

Evaluation of high-risk factors and the diagnostic value of alpha-fetoprotein in the stratification of primary liver cancer

BACKGROUND

Alpha-fetoprotein (AFP) is one of the diagnostic standards for primary liver cancer (PLC); however, AFP exhibits insufficient sensitivity and specificity for diagnosing PLC.

AIM

To evaluate the effects of high-risk factors and the diagnostic value of AFP in stratified PLC.

METHODS

In total, 289 PLC cases from 2013 to 2019 were selected for analysis. First, the contributions of high-risk factors in stratifying PLC were compared according to the following criteria: Child–Pugh score, clinical stage of liver cirrhosis, tumor size, and Barcelona Clinic Liver Cancer (BCLC) stage. Then, the diagnostic value of AFP was evaluated in different stratifications of PLC by receiver operating characteristic curves. For PLC cases in which AFP played little role, the diagnostic values of carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA 19-9), gamma-glutamyl transferase (GGT), and AFP were analyzed.

RESULTS

The roles of high-risk factors differed in stratified PLC. The incidence of smoking and drinking history was higher in PLC with Child–Pugh scores of C (P < 0.0167). The hepatitis B virus (HBV) infection rate in PLC with cirrhosis was more than in PLC without cirrhosis (P < 0.0167). Small tumors were more prone to cirrhosis than large tumors (P < 0.005). BCLC stage D PLC was more likely to be associated with HBV infection and cirrhosis (P < 0.0083). AFP levels were higher in PLC with cirrhosis, diffuse tumors, and BCLC stage D disease. In diagnosing PLC defined as Child–Pugh A, B, and C, massive hepatoma, diffuse hepatoma, BCLC stage B, C, and D, and AFP showed significant diagnostic value [all area under the curve (AUC) > 0.700]. However, these measures were meaningless (AUC < 0.600) in small hepatomas and BCLC A stage PLC, but could be replaced by the combined detection of CEA, CA 19-9, GGT, and AFP (AUC = 0.810 and 0.846, respectively).

CONCLUSION

Stratification of PLC was essential for precise diagnoses and benefited from evaluating AFP levels.

Non-Coding RNAs in Hepatocellular Carcinoma

Liver cancer ranks as the fourth leading cause of cancer-related deaths. Despite extensive research efforts aiming to evaluate the biological mechanisms underlying hepatocellular carcinoma (HCC) development, little has been translated towards new diagnostic and treatment options for HCC patients. Historically, the focus has been centered on coding RNAs and their respective proteins. However, significant advances in sequencing and RNA detection technologies have shifted the research focus towards non-coding RNAs (ncRNA), as well as their impact on HCC development and progression. A number of studies reported complex post-transcriptional interactions between various ncRNA and coding RNA molecules. These interactions offer insights into the role of ncRNAs in both the known pathways leading to oncogenesis, such as dysregulation of p53, and lesser-known mechanisms, such as small nucleolar RNA methylation. Studies investigating these mechanisms have identified prevalent ncRNA changes in microRNAs, snoRNAs, and long non-coding RNAs that can both pre- and post-translationally regulate key factors in HCC progression. In this review, we present relevant publications describing ncRNAs to summarize the impact of different ncRNA species on liver cancer development and progression and to evaluate recent attempts at clinical translation.

miR-2392 functions as tumour suppressor and inhibits malignant progression of hepatocellular carcinoma via directly targeting JAG2

BACKGROUND & AIMS

Dysregulation of microRNA (miRNA) expression in various cancers and their vital roles in malignant progression of cancers are well investigated. Our previous studies have analysed miRNAs that promote malignant progression in hepatocellular carcinoma (HCC); this study aims to systematically elucidate the mechanism of metastasis suppressor miRNAs in HCC.

METHODS

High-throughput RNA sequencing was used to identify anti-metastatic miRNAs. The relative expression levels of miRNAs were confirmed by qRT-PCR. The biological functions of miRNAs were detected in vitro and in vivo. Circulating tumour cells (CTCs) were enriched from blood samples of HCC patients and cultured by three-dimensional (3D) system. Kaplan-Meier and Cox regression were used to analyse the value of potential target mRNAs on overall survival.

RESULTS

miR-2392 was significantly down-regulated in HCC. Overexpression of miR-2392 suppressed proliferation, clonogenicity, mobility, spheroid formation and maintenance of cancer stem cells (CSC)-like characteristics in HCC cells. CTCs from HCC patients with lower serum miR-2392 level had stronger cell spheroid formation ability. A negative correlation between the content of miR-2392 in serum and the number of CTC spheroids had been found. We identified Jagged2 (JAG2) as a direct target of miR-2392. miR-2392 inhibited the expression of JAG2 by targeting 3'-UTR of JAG2. Down-regulation of JAG2 inhibited the overexpression effects of miR-2392 in vitro and in vivo. JAG2 is highly expressed in HCC and is closely related to poor prognosis and survival of patients.

CONCLUSIONS

miR-2392 may play a role as a tumour suppressor to guide the individualized precise treatment of HCC.

The role of miR-370 and miR-138 in the regulation of BMP2 suppressor gene expression in colorectal cancer: preliminary studies

PURPOSE

Colorectal cancer (CRC) is the fourth-most common cancer worldwide and the second most common cancer cause of death in the world. The components of the TGFβ-signalling pathway, which are often affected by miRNAs, are involved in the regulation of apoptosis and cell cycle. Therefore, in the current study, the expression of BMP2 gene in CRC tissues at different clinical stages compared to the non-tumour tissues has been assessed. Moreover, the plasma BMP2 protein concentration in the same group of CRC patients has been validated. Due to the constant necessity to conduct further research of the correlation between specific miRNAs and mRNAs in CRC, in silico analysis has been performed to select miRNAs that regulate BMP2 mRNA.

METHODS

The cDNA samples from tumor and non-tumor tissue were used in a qPCR reaction to determine the mRNA expression of the BMP2 gene and the expression of selected miRNAs. The concentration of BMP2 protein in plasma samples was also measured.

RESULTS

It was indicated that BMP2 was downregulated in CRC tissue. Moreover, miR-370 and miR-138 expression showed an upward trend. Decreased BMP2 with accompanied increasing miR-370 and miR-138 expression was relevant to the malignant clinicopathological features of CRC and consequently poor patient prognosis.

CONCLUSION

Our data suggest that miR-370 with its clear expression in plasma samples may be a potential diagnostic marker to determine the severity of the disease in patients at a later stage of colorectal cancer.

Dampened VEPH1 activates mTORC1 signaling by weakening the TSC1/TSC2 association in hepatocellular carcinoma

BACKGROUND & AIMS

Abnormal activation of mTORC1 signaling occurs at high frequency in hepatocellular carcinoma (HCC). However, the underlying causes of this aberrant activation remain elusive. In this study, we identified ventricular zone expressed pleckstrin homology domain-containing 1 (VEPH1) as a novel tumor suppressor that acts via the mTORC1 axis.

METHODS

We performed quantitative reverse-transcription PCR (92 pairs), western blot (30 pairs), and immunostaining (225 cases) assays in HCC tissue samples to evaluate VEPH1 expression. We explored the functional effects of VEPH1 on tumor growth and metastasis. Molecular and biochemical strategies were used to gain insight into mechanisms underlying the tumor-suppressive function of VEPH1.

RESULTS

VEPH1 is frequently silenced in HCC tissues, primarily resulting from let-7d upregulation. Decreased VEPH1 expression is associated with poor prognosis and aggressive tumor phenotypes in patients with HCC. VEPH1 mediates its tumor-suppressing activity through regulation of cell proliferation, migration and invasion in vitro and in vivo. The VEPH1 fragments 580-625aa and 447-579 aa bind directly to TSC1 (719-1,164aa) and TSC2 (1-420 aa), respectively, enhancing TSC1/TCS2 binding and promoting translocation of TSC2 to the membrane, which leads to increased TSC2 Ser¹³⁸⁷ phosphorylation. Subsequently, Rheb is inactivated by the GTPase activity of TSC2, inhibiting mTORC1 signaling and contributing to changes in HCC carcinogenesis and metastasis. Rapamycin, the mTOR inhibitor, can inhibit the pro-tumorigenic effect of VEPH1 knockdown. Loss of VEPH1 correlates with decreased TSC2 Ser¹³⁸⁷ phosphorylation and increased mTOR activity in HCC specimens.

CONCLUSIONS

The loss of VEPH1 leads to aberrantly activated mTORC1 signaling in HCC; rapamycin (or rapalogs) may serve as an effective treatment option for patients with HCC and dampened VEPH1 expression.

LAY SUMMARY

Abnormally activated mammalian target of rapamycin (mTOR) signaling is associated with poor tumor differentiation, early tumor recurrence and worse overall survival in patients with hepatocellular carcinoma. Herein, we identify low VEPH1 expression as a potential cause of abnormally activated mTOR signaling in hepatocellular carcinoma tissues. mTOR inhibitors could thus be an effective treatment option for patients with HCC and low VEPH1 expression.

Advances in the role of miRNAs in the occurrence and development of osteosarcoma

Osteosarcoma (OS) is the most common primary malignant tumor of the skeletal system in the clinic. It mainly occurs in adolescent patients and the pathogenesis of the disease is very complicated. The distant metastasis may occur in the early stage, and the prognosis is poor. MicroRNAs (miRNAs) are non-coding RNAs of about 18–25 nt in length that are involved in post-transcriptional regulation of genes. miRNAs can regulate target gene expression by promoting the degradation of target mRNAs or inhibiting the translation process, thereby the proliferation of OS cells can be inhibited and the apoptosis can be promoted; in this way, miRNAs can affect the metabolism of OS cells and can also participate in the occurrence, invasion, metastasis, and recurrence of OS. Some miRNAs have already been found to be closely related to the prognosis of patients with OS. Unlike other reviews, this review summarizes the miRNA molecules closely related to the development, diagnosis, prognosis, and treatment of OS in recent years. The expression and influence of miRNA molecule on OS were discussed in detail, and the related research progress was summarized to provide a new research direction for early diagnosis and treatment of OS.

Inhibiting effect of MicroRNA-3619-5p/PSMD10 axis on liver cancer cell growth in vivo and in vitro

AIMS

Liver cancer is one of the leading causes of cancer death worldwide owing to its delayed diagnosis and absence of efficient treatment at advanced TNM stages. Increasing evidence demonstrated that microRNAs are implicated in tumorgenesis and cancer development by regulating cancer-related proteins. This study aimed to explore the effect of miR-3619-5p on cell growth in liver cancer.

MAIN METHODS

The effect of miR-3619-5p on cell proliferation was measured by quantitative real-time PCR, MTT assay, flow cytometry, and Immunofluorescence assay. The interaction between miR-3619-5p and PSMD10 was validated using dual-luciferase. The expression of PSMD10 and Ki67 was further determined by immunohistochemistry.

KEY FINDINGS

MiR-3619-5p over-expression remarkably inhibited cell proliferation and induced G1 phase arrest, accompanied with reduced expression of proliferating cell nuclear antigen. The expression of miR-3619-5p was negatively correlated to that of PSMD10, and PSMD10 was validated to be a downstream target of miR-3619-5p. Moreover, miR-3619-5p induced suppressed proliferation and G1 phase arrest were abrogated by elevated the expression of PSMD10 in liver cancer cells. PSMD10 over-expression also induced phosphorylation of signal transducer and activator of transcription 3 (STAT3) and retinoblastoma protein (Rb1). Besides, elevated cyclin A, cyclin D1 and cyclin E expression supported that PSMD10 promoted the progress of cell cycle. In addition, miR-3619-5p inhibited tumor growth in vivo by targeting PSMD10, accompanied with blocked cell cycle.

SIGNIFICANCE

In conclusion, our findings revealed that miR-3619-5p inhibits cancer cell proliferation by targeting PSMD10, and miR-3619-5p as a potential therapeutic target for the treatment of liver cancer.

Diagnostic value of fibrinogen to prealbumin ratio and gamma-glutamyl transpeptidase to platelet ratio in the progression of AFP-negative hepatocellular carcinoma

Background

This study aimed to comprehensively assess the diagnostic value of fibrinogen to prealbumin ratio (FPR) and gamma-glutamyl transpeptidase to platelet ratio (GPR) as single markers or in combination in patients with alpha-fetoprotein-negative (AFP-negative) hepatocellular carcinoma (HCC).

Methods

A total of 199 healthy controls and 515 AFP-negative patients were enrolled in this study, including 180 HCC inpatients, 151 liver cirrhosis (LC) patients, and 184 chronic hepatitis (CH) cases. Mann-Whitney U or Kruskal-Wallis H test were used to analyze differences between groups in laboratory parameters and clinicopathological features. The diagnostic value of FPR and GPR, alone or in combination, in AFP-negative HCC (AFP-NHCC) patients was determined via a receiver operating characteristic (ROC) curve.

Results

The levels of FPR and GPR were gradually increased in the development of AFP-NHCC and positively correlated with the tumor size and Barcelona Clinic Liver Cancer (BCLC) stages. Moreover, GPR was associated with Edmondson-Steiner grades. After univariate logistic regression analysis, FPR and GPR remained independent predictors of adverse outcomes. The combination of FPR and GPR had a good ability to detect AFP-NHCC from the control group (area under curve [AUC] = 0.977), AFP-negative CH (AUC = 0.745), and AFP-negative LC (AUC = 0.666). FPR combined with GPR possessed a larger area (0.943, 0.971) and sensitivity (87.50%, 89.81%) than FPR or GPR alone for differentiating AFP-NHCC with tumor size < 3 cm or at the BCLC-A stage.

Conclusions

The pretreatment levels of FPR and GPR played vital roles in the development of AFP-NHCC, especially in patients with early or small AFP-NHCC.

Systems biology based meth-miRNA-mRNA regulatory network identifies metabolic imbalance and hyperactive cell cycle signaling involved in hepatocellular carcinoma onset and progression

Background

Hepatocellular carcinoma (HCC) is one of the leading cause of cancer associated deaths worldwide. Independent studies have proposed altered DNA methylation pattern and aberrant microRNA (miRNA) levels leading to abnormal expression of different genes as important regulators of disease onset and progression in HCC. Here, using systems biology approaches, we aimed to integrate methylation, miRNA profiling and gene expression data into a regulatory methylation-miRNA–mRNA (meth-miRNA–mRNA) network to better understand the onset and progression of the disease.

Methods

Patients’ gene methylation, miRNA expression and gene expression data were retrieved from the NCBI GEO and TCGA databases. Differentially methylated genes, and differentially expressed miRNAs and genes were identified by comparing respective patients’ data using two tailed Student’s t-test. Functional annotation and pathway enrichment, miRNA–mRNA inverse pairing and gene set enrichment analyses (GSEA) were performed using DAVID, miRDIP v4.1 and GSEA tools respectively. meth-miRNA–mRNA network was constructed using Cytoscape v3.5.1. Kaplan–Meier survival analyses were performed using R script and significance was calculated by Log-rank (Mantel-Cox) test.

Results

We identified differentially expressed mRNAs, miRNAs, and differentially methylated genes in HCC as compared to normal adjacent tissues by analyzing gene expression, miRNA expression, and methylation profiling data of HCC patients and integrated top miRNAs along with their mRNA targets and their methylation profile into a regulatory meth-miRNA–mRNA network using systems biology approach. Pathway enrichment analyses of identified genes revealed suppressed metabolic pathways and hyperactive cell cycle signaling as key features of HCC onset and progression which we validated in 10 different HCC patients’ datasets. Next, we confirmed the inverse correlation between gene methylation and its expression, and between miRNA and its targets’ expression in various datasets. Furthermore, we validated the clinical significance of identified methylation, miRNA and mRNA signatures by checking their association with clinical features and survival of HCC patients.

Conclusions

Overall, we suggest that simultaneous (1) reversal of hyper-methylation and/or oncogenic miRNA driven suppression of genes involved in metabolic pathways, and (2) induction of hyper-methylation and/or tumor suppressor miRNA driven suppression of genes involved in cell cycle signaling have potential of inhibiting disease aggressiveness, and predicting good survival in HCC.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0804-3) contains supplementary material, which is available to authorized users.

Current Status and Perspective Biomarkers in AFP Negative HCC: Towards Screening for and Diagnosing Hepatocellular Carcinoma at an Earlier Stage

Hepatocellular carcinoma (HCC) is one of the most malignant cancer with high morbidity and mortality which lead to a serious burden to society. AFP (alpha-fetoprotein) is the most widely used serum biomarker to detect HCC worldwide. However, no AFP elevation have been found in many HCC and AFP analysis can't be used to screen HCC in these cases. Currently, many studies have been carried out to find reliable biomarker in diagnosing AFP-negative HCC. Such biomarker would help the diagnosis of AFP-negative HCC, ensuring the timely initiation of treatment. In this review, we highlight the important role of biomarkers that can differentiate AFP-negative HCCs, and discuss their potential clinical applications as biomarkers for the diagnosis of AFP-negative HCC.

MiR-422a targets MAPKK6 and regulates cell growth and apoptosis in colorectal cancer cells

The important role of miR-422a in tumor has been reported in several studies. Recent research discovered that the expression of miR-422a was significantly decreased in colorectal cancer tissues, providing miR-422a as a tumor suppressor in CRC. However, the concrete mechanism of miR-422a regulating CRC cell is still unclear. In this study, we demonstrated that miR-422a could inhibit CRC cell growth and promote cell apoptosis via in vitro analyses. Moreover, computational methods were adopted to identify the targets of miR-422a. We found MAPKK6 was the direct target of miR-422a. Consequently, we further elucidated that miR-422a inhibited CRC cell growth and induced cell apoptosis by inhibiting p38/MAPK pathway. Besides that, we established the tumor xenograft model using nude mice and the inhibitory effects on tumor volumes and weights by miR-422a mimic transfection were also detected. Taken together, these findings demonstrated miR-422a exerted anti-cancer activities on CRC, which could be potentially used for CRC prognosis prediction and treatment.

Involvement of inflammation and its related microRNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most commonly diagnosed type of cancer. The tumor inflammatory microenvironment regulates almost every step towards liver tumorigenesis and subsequent progression, and regulation of the inflammation-related signaling pathways, cytokines, chemokines and non-coding RNAs influences the proliferation, migration and metastasis of liver tumor cells. Inflammation fine-tunes the cancer microenvironment to favor epithelial-mesenchymal transition, in which cancer stem cells maintain tumorigenic potential. Emerging evidence points to inflammation-related microRNAs as crucial molecules to integrate the complex cellular and molecular crosstalk during HCC progression. Thus understanding the mechanisms by which inflammation regulates microRNAs might provide novel and admissible strategies for preventing, diagnosing and treating HCC. In this review, we will update three hypotheses of hepatocarcinogenesis and elaborate the most predominant inflammation signaling pathways, i.e. IL-6/STAT3 and NF-κB. We also try to summarize the crucial tumor-promoting and tumor-suppressing microRNAs and detail how they regulate HCC initiation and progression and collaborate with other critical modulators in this review.

MicroRNA 141 Expression Is a Potential Prognostic Marker of Biliary Tract Cancers

Background/Aims

In recent years, a large number of micro-ribonucleic acids (miRNAs) have been identified as putative prognostic biomarkers for solid cancers because of their role in controlling the expression of oncogenes and tumor suppressor genes. The aim of this study was to verify the utility of miRNA 141 as a prognostic biomarker of biliary tract cancers.

Methods

From June 2010 to June 2012, common bile duct cancer tissue samples and matched noncancerous tissues from the ampulla of Vater were obtained from patients with biliary tract cancer undergoing endoscopic retrograde cholangiopancreatography. Using quantitative real-time polymerase chain reaction assays, we measured the mean relative expression levels of miRNA 141 in both groups of tissues. Overexpression of miRNA 141 was defined as a greater than 2-fold increase in expression levels as determined by the 2^−ΔΔCt method.

Results

In a cohort of 38 patients with biliary tract cancers (seven gallbladder, 13 hilar, and 18 distal bile duct cancers), 26 patients (68.4%) were male, and the median age was 69.5 (52 to 85) years. Nineteen patients (50%) had undergone R0 resection procedures, including three Whipple operations, seven pylorus-preserving pancreaticoduodenectomies, six bile duct resections, and three extended lobectomies. Among the patients who had undergone R0 resection, the overexpression of miRNA 141 was significantly associated with shorter disease-free survival and a greater risk of angiolymphatic invasion. Among the patients who did not undergo R0 resection, miRNA 141 overexpression was significantly associated with reduced overall survival.

Conclusions

Overexpression of miRNA 141 is an indicator of a poor prognosis in patients with biliary tract cancer, suggesting that miRNA 141 may be a valuable prognostic biomarker of this disease.

Regulatory role of miR-211-5p in hepatocellular carcinoma metastasis by targeting ZEB2

Hepatocellular carcinoma (HCC) is the most common type of cancer and the rapid tumor growth, drug resistance and metastasis are the major problems for HCC therapy. MicroRNAs (miRNAs) involve in various cell biological processes in HCC. ZEB2 plays crucial roles in HCC progression. ZEB2 is regulated by some identified miRNAs, but there needs to find new miRNAs regulating ZEB2 expression for better understanding the molecular mechanism of HCC. In the present study, ZEB2 was identified as a direct target of miR-211-5p, which was a potential oncogene in cancer. We found that miR-211-5p levels in HCC tissues were lower than the compared normal tissues. ZEB2 expression was higher in HCC tissues and was negatively related to miR-211-5p levels. Overexpression of miR-211-5p in human HCC cell lines (HepG2 and 7721) caused the delay of cell proliferation, apoptosis and drug sensitivity. Summarily, our study demonstrates that miR-211-5p may play a suppressing role in HCC by inhibiting ZEB2 expression.

Diagnostic and prognostic potential of serum microRNA-4651 for patients with hepatocellular carcinoma related to aflatoxin B1

Background

The serum microRNAs have been reported as potential biomarkers for hepatitis virus-related hepatocellular carcinoma (HCC); however, their role in aflatoxin B1 (AFB1)-related HCC to has not yet been evaluated.

Materials and Methods

We conducted a case-control study, including 366 HCC cases and 662 controls without any evidence of tumors, to identify and assess diagnostic and prognostic potential of serum microRNAs for AFB1-related HCC. The sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were used to elucidate diagnostic performance, and to compare the microRNAs with α-fetoprotein (AFP) at a cutoff of 20 ng/mL (AFP20) and 400 ng/mL (AFP400).

Results

We found 8 differentially expressed microRNAs via the microRNA array analysis; however, only microRNA-4651 was further identified to detect AFB1-positive HCC but not AFB1-negative HCC. For AFB1-positive HCC, microRNA-4651 showed higher accuracy and sensitivity than AFP400 (AUC, 0.85 vs. 0.72; Sensitivity, 78.1% vs. 43.0%). Compared to AFP20, microRNA-4651 exhibited higher potential in identifying small-size (0.68 vs. 0.84 for AUC and 36.7% vs. 75.5% for sensitivity, respectively) and early-stage HCC (0.69 vs. 0.84 for AUC and 38.7% vs. 75.7% for sensitivity, respectively). Additionally, miR-4651 was also associated with HCC prognosis (hazard risk value, 2.67 for overall survival and 3.62 for tumor recurrence analysis).

Conclusions

These data suggest that serum microRNA-4651 may be a useful marker for HCC diagnosis and prognosis, especially AFB1-positive cases.

Clinicopathological role of miR-30a-5p in hepatocellular carcinoma tissues and prediction of its function with bioinformatics analysis

BACKGROUND

It has been reported that deregulation or dysfunction of microRNAs (miRNAs) plays an essential part in the hepatocarcinogenesis. However, the contribution and mechanism of microRNA-30a-5p (miR-30a-5p) in hepatocellular carcinoma (HCC) remains largely unknown. Therefore, our aim was to investigate the clinicopathological role of miR-30a-5p in HCC tissues and explore its potential pathways in this study.

METHODS

The expression of miR-30a-5p was measured in 95 HCC and adjacent noncancer tissues by real-time reverse transcription quantitative polymerase chain reaction. The relationship between miR-30a-5p expression levels and clinicopathological parameters was also analyzed. Furthermore, the potential target genes of miR-30a-5p were collected via online prediction and literature searching. Gene ontology and pathway enrichment analyses were used to identify the possible function of miR-30a-5p in HCC.

RESULTS

Compared with adjacent noncancer tissues (2.23±0.77), expression level of miR-30a-5p was significantly lower in HCC tissues (1.26±0.66, P<0.001). MiR-30a-5p expression was evidently correlated with tumor nodes, metastasis, tumor-node-metastasis stage, portal vein tumor embolus, vascular invasion, and status of tumor capsule (all P<0.05). A total of 878 genes were finally used for the biological informatics analyses. These prospective target genes were highly enriched in various key pathways, for instance, Ubiquitin-mediated proteolysis, Axon guidance, Neurotrophin signaling pathway, Amyotrophic lateral sclerosis, and ErbB signaling pathway.

CONCLUSION

In conclusion, this study clarifies that the downregulation of miRNA-30a-5p might play a vital part in the incidence and progression of HCC via targeting various prospective genes and pathways. Future validation is required to further explore the prospective molecular mechanism of miR-30a-5p in HCC.

Comprehensive investigation of aberrant microRNA profiling in bladder cancer tissues

There has been accumulative evidence that microRNAs (miRNAs) play essential roles in the tumorigenesis and progression of bladder cancer. However, individual studies and small sample size caused discrepant outcomes. Thus, the current study focused on a comprehensive profiling of all differentially expressed miRNAs in a total of 519 bladder cancer tissue samples, based on miRNA microarray data. Altogether, 11 prioritized miRNAs stated by 21 published microarray datasets, including five down-regulated (miR-133a-3p, miR-1-3p, miR-99a-5p, miR-490-5p, and miR-133b) and six up-regulated candidate miRNAs (miR-182-5p, miR-935, miR-518e-3p, miR-573, miR-100-3p, and miR-3171) were analyzed with vote-counting strategy and a Robust Rank Aggregation method. Subsequently, miRNA in silico target prediction and potential pathway enrichment analysis were performed to investigate the prospective molecular mechanism of miRNAs in the tumorigenesis of bladder cancer. We found that most of the relative pathways of the aberrantly expressed miRNAs found in the current study were closely correlated with different biological processes, cellular components, molecular functions, cancer pathogeneses, and some cell signalings, such as Wnt signaling, insulin/IGF, PI3 kinase, and FGF signaling pathways. Hence, a comprehensive overview on the miRNA expression pattern in bladder cancer tissues was gained by the current study. These miRNAs might be involved in the tumorigenesis and deterioration of bladder cancer.

miR-422a is an independent prognostic factor and functions as a potential tumor suppressor in colorectal cancer

AIM: To determine the expression of miR-422a in colorectal cancer (CRC) tissues and to further explore the prognostic value and function of miR-422a in CRC carcinogenesis.

METHODS: miR-422a expression was analyzed in 102 CRC tissues and paired normal mucosa adjacent to carcinoma by quantitative real-time PCR. The relationship of miR-422a expression with clinicopathological parameters was also analyzed. Kaplan-Meier analysis and Cox multivariate analysis were performed to estimate the potential role of miR-422a. Cell proliferation, migration, and invasion were used for in vitro functional analysis of miR-422a.

RESULTS: The levels of miR-422a were dramatically reduced in CRC tissues compared with normal mucosa (P < 0.05), and significantly correlated with local invasion (P = 0.004) and lymph node metastasis (P < 0.001). Kaplan-Meier survival and Cox regression multivariate analyses revealed that miR-422a expression (HR = 0.568, P = 0.015) and clinical TNM stage (HR = 2.942, P = 0.003) were independent prognostic factors for overall survival in CRC patients. Furthermore, in vitro experiments showed that overexpression of miR-422a inhibited the proliferation, migration, and invasion of SW480 and HT-29 cells.

CONCLUSION: Down-regulation of miR-422a may serve as an independent prognosis factor in CRC. MiR-422a functions as a tumor suppressor and regulates progression of CRC.

Identifying microRNA panels specifically associated with hepatocellular carcinoma and its different etiologies

AIM

Deregulation of microRNAs (miRNAs) expression has been identified in hepatocellular carcinoma (HCC), but few results are consistent. The objective of this study is to investigate "HCC tumor type specific" and "tumor common" miRNA panels.

METHODS

The authors integrate and analyze clinical, etiologic and miRNA profiles data from 9 types of solid tumors in The Cancer Genome Atlas (TCGA) and HCC data from Columbia University Medical Center (CUMC).

RESULTS

Levels of 33 miRNAs were significant different between HCC tumor and paired non-tumor tissues (over 2-fold changes) after Bonferroni correction for multiple comparisons, and most (28 miRNAs) were down-regulated in HCC tumors. Using this panel, the authors well classified HCC tumor tissues with 4 misclassifications among 48 paired tissues. Validating this panel in an additional 302 HCC tumor tissues, the authors almost perfectly distinguished tumor from non-tumor tissues with only two misclassifications (99% of HCC tissues correctly classified). Evaluating miRNA profiles in 32 independent HCC paired tissues from CUMC, the authors observed 40 miRNAs significantly deregulated in HCC with over 2-fold changes; 14 overlapped with those identified in TCGA. Subgroup analyses by HCC etiology found that 4 upregulated and 8 downregulated miRNAs were significantly associated with alcohol-related HCC. There were 7 and 4 miRNAs significantly associated with hepatitis B virus- and hepatitis C virus-related HCC, respectively. Data for the first time revealed that miR-24-1, miR-130a and miR-505 were significantly down-regulated only in HCC tumors; miR-142 and miR-455 were significantly down-regulated in HCC, but up-regulated in 5 other solid tumors; suggesting their HCC "tumor type specific" characteristics. A panel of 8 miRNAs was significant in at least 5 tumor types, including HCC, and was identified as "tumor common" marker.

CONCLUSION

The authors concluded that aberrant miRNA panels have HCC "tumor type specificity" and may be affected by etiologic factors.

An ANCCA/PRO2000-miR-520a-E2F2 regulatory loop as a driving force for the development of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in Asia especially in China. We previously identified that ANCCA/PRO2000 as an important proliferation-associated protein predicted poor prognosis of patients with HCC. However, the molecular mechanisms of ANCCA/PRO2000 leading to hepatocarcinogenesis and progression are still obscure. In the present study, we found that ANCCA/PRO2000 overexpression in HCC specimens correlated with aggressive tumor behavior and poor survival. Furthermore, ANCCA/PRO2000 exerts strong oncogenic function in HCC and promotes cell proliferation by regulating E2F2 expression, a critical cell cycle regulator. Notably, miR-520a is an intermediate regulator between ANCCA/PRO2000 and E2F2. Mechanistically, ANCCA/PRO2000 not only interacts with E2F2 but also negatively regulates miR-520a that inhibits E2F2 to cooperatively promote in vitro and in vivo growth of HCC cells. Moreover, we demonstrated that ANCCA/PRO2000 enhances the migratory capacity of HCC cells partially by suppressing ERO1L and G3BP2 expression. Additional research identified that miR-372, as a prognostic factor for HCC, could directly target ANCCA/PRO2000. Our results suggest the ANCCA/PRO2000-miR-520a-E2F2 regulatory loop as a driving force for HCC development and ANCCA/PRO2000 as a potential therapeutic target for HCC.

MicroRNA-101 sensitizes hepatocellular carcinoma cells to doxorubicin-induced apoptosis via targeting Mcl-1

MicroRNAs (miRNAs/miRs) are important regulators of multiple cellular processes, and their dysregulation is a common event in tumorigenesis, including the development of hepatocellular carcinoma (HCC). Studies have shown that certain miRNAs are associated with resistance to chemotherapy or drug sensitization; however, the underlying mechanisms have largely remained elusive. Multiple drug resistance is a major barrier for the treatment of advanced HCC. In the present study, miR-101 was observed to be downregulated in a panel of HCC cell lines, suggesting that it has a tumor suppressor role. Furthermore, transfection of miR-101 significantly enhanced the cytotoxicity of doxorubicin to HepG2 cells. While overexpression of miR-101 did not influence the accumulation of doxorubicin, it promoted the apoptosis-inducing effect of doxorubicin in HepG2 cells. A bioinformatics analysis predicted that miR-101 directly targeted the 3'-untranslated region of myeloid cell leukemia 1 (Mcl-1), which was verified by a luciferase reporter assay. Finally, transfection of HepG2 cells with Mcl-1 expression plasmid inhibited apoptosis caused by doxorubicin plus miR-101 expression. In conclusion, the present study showed that miR-101 is a negative regulator of Mcl-1 in HCC, and the combination of miR-101 expression with doxorubicin may represent a novel approach for the treatment of HCC.

Fucoidan Elevates MicroRNA-29b to Regulate DNMT3B-MTSS1 Axis and Inhibit EMT in Human Hepatocellular Carcinoma Cells

Accumulating evidence has revealed that fucoidan exhibits anti-tumor activities by arresting cell cycle and inducing apoptosis in many types of cancer cells including hepatocellular carcinoma (HCC). Exploring its effect on microRNA expression, we found that fucoidan markedly upregulated miR-29b of human HCC cells. The induction of miR-29b was accompanied with suppression of its downstream target DNMT3B in a dose-dependent manner. The reduction of luciferase activity of DNMT3B 3'-UTR reporter by fucoidan was as markedly as that by miR-29b mimic, indicating that fucoidan induced miR-29b to suppress DNMT3B. Accordingly, the mRNA and protein levels of MTSS1 (metastasis suppressor 1), a target silenced by DNMT3B, were increased after fucoidan treatment. Furthermore, fucoidan also down-regulated TGF-β receptor and Smad signaling of HCC cells. All these effects leaded to the inhibition of EMT (increased E-cadherin and decreased N-cadherin) and prevention of extracellular matrix degradation (increased TIMP-1 and decreased MMP2, 9), by which the invasion activity of HCC cells was diminished. Our results demonstrate the profound effect of fucoidan not only on the regulation of miR-29b-DNMT3B-MTSS1 axis but also on the inhibition of TGF-β signaling in HCC cells, suggesting the potential of using fucoidan as integrative therapeutics against invasion and metastasis of HCC.