Detection of DNA methylated microRNAs in hepatocellular carcinoma.

Irregular methylation, including DNA hypomethylation and/or promoter gene CpG hypermethylation, is involved in the pathogenesis of several solid tumors, including liver cancer. miRNAs are small, endogenous, noncoding RNAs that serve as posttranscriptional regulators of gene expression. Previous research has focused on identifying the factors that regulate the expression of miRNAs in hepatic carcinogenesis. The factors that regulate miRNA expression are not clear; in particular, the role of DNA methylation, an epigenetic regulatory factor that controls miRNA transcription, has not been clarified. The goal of this study is to explore our understanding of the mechanism by which HCC may develop and progress through identification of the role of epigenetically regulated miRNAs influences in the liver carcinogenesis. The current study included 60 patients who were well diagnosed as HCC patients. 60 patients who suffer from liver cirrhosis were also enrolled in the current study and 30 healthy control subjects who serve as control group. All patients will be subjected to: full clinical assessment, abdominal ultrasound, Blood sample will be withdrawn from every patients for both biochemical and serum detection of microRNAs (191-203 -335) by real time PCR. We found that all studied microRNAs were down regulated among HCC patients when compared to cirrhotic patients and controls (p value: 0.005, 0.005 and 0.001 for microRNAs 191, 203 and 335 respectively). Moreover, these microRNAs can discriminate cases of HCC from risky cirrhotic patients. We can conclude that downregulated microRNAs among HCC cases proposed a pattern to explain the role of DNA methylation on miRNA and gene expression in HCC.

Relationship Between Serum microRNA155 and Telomerase Expression in Hepatocellular Carcinoma.

BACKGROUND AND AIMS: Activation of telomerase reverse transcriptase (hTERT) has a role in liver carcinogenesis where telomerase is normally suppressed in most human somatic tissues after birth. In the current study we aimed to detect the significance of hTERT mRNA in early detection of hepatocellular carcinoma (HCC) and to determine the relationship between serum microRNA155 and telomerase expression. METHODS: Serum and liver tissue samples were collected from 40 patients (17 samples from patients with liver cirrhosis and 23 samples from patients with HCC) and 12 blood samples from healthy subjects were collected. Serum miRNA155 levels and blood and tissue hTERT mRNA were detected by real-time quantitative reverse-transcriptase PCR (RT-qPCR) among liver cirrhosis and HCC patients. Moreover, miR-155, blood and tissue hTERT levels were analyzed in relation to clinical and pathological features. RESULTS: Calculated expression of miRNA155 revealed that relative quantity (RQ) miR 155 was overexpressed in sera of HCC patients when compared to patients with liver cirrhosis and controls (p <0.0001). The median values of serum telomerase were significantly increased among HCC patients than in patients with liver cirrhosis and controls (p = 0.04). Moreover, tissue expression of telomerase was significantly higher in malignant tissue more than adjacent nonmalignant tissue among HCC patients (p = 0.02). It was also found that tissue expression of telomerase was significantly decreased in tissue of liver cirrhosis patients (p = 0.03). Interestingly, we found that blood telomerase was directly correlated with serum miRNA155 (p = 0.003). CONCLUSIONS: Both mir 155 and telomerase may have a role in development of HCC and mir 155 could regulate telomerase expression during liver carcinogenesis.

Relation between microRNAs and Apoptosis in Hepatocellular Carcinoma.

AIM: To determine the relation between serum microRNAs and apoptotic markers as regards development of HCC to understand the underlying mechanism of HCV related hepatocarcinogenesis. PATIENTS AND METHODS: A total of 65 serum samples (25 samples from controls, 20 samples from hepatitis and 20 samples from HCC patients) were collected for miRNAs (mir 21, mir 199-a, and mir 155) detection. Human Programmed cell death protein-4 (PDCD-4) and Human Cytochrome-C (CYT-C) were determined. RESULTS: miRNAs 21 and 155 were over expressed in sera of patients with HCC compared to patients with chronic hepatitis (p < 0.0001). While serum means values of miR 199a was significantly decreased among HCC group patients when compared to patients with chronic hepatitis (p < 0.0001). The serum levels of PCDC4 and CYTC were increased in patients with HCC when compared to chronic hepatitis patients. They were also increased in patients with chronic hepatitis when compared to controls (p < 0.05, significant). There was direct correlations between apoptotic markers and oncomirs miRNAs 21 and 155 while apoptotic markers were inversely correlated with miRNA 199-a. CONCLUSION: Both microRNAs and apoptotic markers have roles in HCC pathogenesis. It seems that oncogenic microRNAs induce liver carcinogenesis in HCV patients irrespective of suppression of apoptosis.

The potential role of miRNAs 21 and 199-a in early diagnosis of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is regarded as one of the most common malignancies and among the leading causes of cancer death among the whole world. The most urgent needs are to find sensitive markers for early diagnosis for HCC. MicroRNAs (miRNAs) are reported as a group of small non-coding RNAs that can function as endogenous RNA interference to regulate expression of the targeted genes. This study was conducted to detect the serum and tissue expression of miR 21 and miR 199-a to be applied as early detectors for HCC. METHODS: A total of 40 serum and tissue samples (17 samples from chronic hepatitis and 23 samples from HCC patients) were collected. The levels of the two mature miRNAs (miR-21 and miR-199-a) were detected by real time quantitative reverse-transcriptase PCR (RT-qPCR) in sera and tissues of chronic hepatitis and HCC patients. Besides, miR-21 and miR-199-a levels in relation to clinical and pathological factors were explored. RESULTS: We found that the expression of serum miR-21 was distinctly increased in HCC compared with chronic hepatitis (P<0.001). miR 199-a was distinctly decreased in HCC compared with chronic hepatitis (P<0.001). In addition, median of miR 21 was increased in malignant when compared to adjacent non-malignant tissues without significant differences (P=0.191) while miR 199-a was significantly decreased in malignant when compared to adjacent nonmalignant tissues (P<0.001). ROC analysis showed that miR-21 and miR-199-a might be potential biomarkers for HCC. CONCLUSIONS: In conclusion, the expression of miR-21 was significantly up-regulated and miR-199-a was significantly down regulated in serum of patients with HCC. Due to their reasonable sensitivity and specificity for disease progression, miR-21 and miR-199-a could be used as potential circulating biomarkers for HCC.

The possible role of Cytochrome c and programmed cell death protein 4 (PDCD4) on pathogenesis of hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is regarded as one of the most common malignancies and among the leading causes of cancer death in the whole world. Apoptosis is a fundamental process controlling cell death and plays a critical role in normal development of multicellular organisms. When abnormalities occur in apoptosis, a variety of diseases are caused, including cancer. The aim of the current study was to determine the serum expression of Cytochrome c and PDCD4 among patients with hepatocellular carcinoma and chronic hepatitis. PATIENTS AND METHODS: A total of 40 serum and tissue samples (17 samples from chronic hepatitis and 23 samples from HCC patients) were collected. Apoptotic markers in serum were carried out using the quantitative sandwich enzyme immunoassay technique. RESULTS: We found that serum levels of PCDC4 and Cytochrome c were increased in patients with HCC when compared to chronic hepatitis patients. They were also increased in patients with chronic hepatitis when compared to controls (p < 0.05, significant). Analyzing the impact of HCC characters on serum values of PDCD4 and Cytochrome c revealed that the mean values of both PDCD4 and Cytochrome c are significantly higher in cases with single lesion of HCC (p < 0.05, significant). Right lobe location of HCC lesions has the highest mean values of PDCD4 (p < 0.05, significant). As regards grade of differentiation, grade П has higher mean values of Cytochrome c (p < 0.05, significant). CONCLUSION: Serum levels of Cytochrome c and PDCD4 are increased in patients with cirrhosis and hepatocellular carcinoma and could be used as diagnostic aid for HCC.