الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Summary
Hepatocellular carcinoma (HCC) is the most common type
of primary liver cancer, accounting for between 85% and 90% of
it. It is a challenging malignancy of global importance, associated
with a high rate of mortality with roughly 550,000 - 600,000 new
HCC cases globally each year. Hepatitis C virus (HCV) is one of
the major risk factors for the development of HCC. Egypt is
considered as a country with rising incidence of HCC.
Unfortunately, approximately 85% of HCC patients are being
presented at a late stage. MicroRNAs (miRNAs) are a non-coding
family of genes involved in post-transcriptional gene regulation.
These transcripts play important role in hepatocarcinogenesis
where they control several cell processes such as cell
proliferation, cell differentiation, and cell death.
The aim of the present study was to explore the potential
usefulness of some liver diseases-associated serum miRNAs
namely miR-17, miR-21, miR-25, miR-30c, miR-93, miR-106b
and miR-222 as novel noninvasive markers for diagnosis of
HCV-related hepatocellular carcinoma in Egyptian patients.
Another aim is to find the concordance in both serum and tissue
samples.
A total of 25 patients with HCC and 52 patients with HCV
were selected to participate in the study. Control group included
Summary
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50 serum samples which obtained from normal blood donors who
were negative for HBV, HCV and HCC. For tissue study, six
tissue biopsied were obtained from 6 healthy volunteers who
donate a part of their liver “lobe of their liver” in transplantation
surgery under the approval of ethics) (they were also negative for
HBV, HCV and HCC) and used as controls.
Total RNAs extraction was performed in all groups, cDNA
was synthesized and quantitative RT-PCR was done for detection
of expression pattern of the candidate miRNA, namely miR-17,
miR-21, mi-25, miR-30c, miR-93, miR-106b and miR-222. Then
the relative gene expression of the target miRNAs was calculated
according to the Livak’s 2-ΔΔCt equation in relation to miR-16 and
RNU6B as internal control genes. Statistical analyses were then
performed using IBM SPSS (V.20).
Deregulation in serum level of miRNAs was detected in 6
out of 7 miRNA studied in HCC patients. Four were up-regulated
namely miR-21, miR-25, miR-30c and miR-222 and two were
down-regulated namely miR-17 and miR-106b as compared to
healthy normal controls. In patients with HCV infection, miR-21,
miR-25, miR-93 and miR-222 serum expression levels were
elevated while serum expression level of miR-30c was decreased
compared to healthy controls. Five miRNAs (miR-17, miR-21,
miR-30c, miR-106b and miR-222) were found to be significantly
deregulated in serum of HCC-patients compared to HCV-infected
Summary
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patients. Matching was observed only in miR-106b and miR-222
expression levels between serum and tissue samples in HCC
patients. Therefore, it was decided to study the potential of these
2 miRNAs in detection of HCC among HCV-infected patients.
No correlation was detected between the relative
expression level of miR-106b and clinico-pathological
parameters. A significant correlation was detected between the
relative expression level of miR-222 and liver cirrhosis
(P=0.048). On the other hand, a significant correlation (P < 0.001)
was detected between the expression levels of the 2 miRNAs.
Receiver Operating characteristics (ROC) analysis has
shown that the serum level of miR-106b has moderate sensitivity
(46.2%) and high specificity (84%) in HCC diagnosis; while miR-
222 has moderate specificity (59.6%) and sensitivity (72%). In
addition, by combining either the miRNA-106b or the miR-222
levels with the AFP level, the sensitivity was notably increased
compared with AFP alone, suggesting that both serum miRNA-
106b and miR-222 have some diagnostic potential, both
individually and in combination with AFP. Further analysis is
needed to evaluate the diagnostic power of circulating miR-106b
and miR-222 for hepatocellular carcinoma. Future studies will
focus on developing a clinically useful early diagnostic test for
HCC using these biomarkers and will validate our current data in
a larger sample size study