الفهرس 
INTRODUCTION AND AIM OF THE WORKOnly 14 pages are availabe for public view
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Abstract
Hepatocellular carcinoma (HCC) is one of the most aggressive human cancers and the third leading cause of death worldwide. Despite the recent advance in diagnosis and treatment of HCC, it remains a highly lethal disease due to recurrence and /or metastasis. HCC is an example of inflammation-related cancer, as the chronic inflammatory state appears to be necessary for the initiation and development of liver cancer.
Hepatitis C virus (HCV) infection is a major cause of chronic liver disease, which can lead to the development of liver cirrhosis and hepatocellular carcinoma. Recently, the activation of cyclooxygenase-2 (Cox-2) has been implicated in the HCV-associated hepatocellular carcinoma. Cox-2 is inducible by a variety of stimuli, including oncogenes, mitogens, cytokines, growth factors, inflammatory molecules, endotoxins, and tumor promoters.
The present study included 17 HCC tissue samples and 21 adjacent non-tumor liver tissues obtained from 22 HCC patients underwent curative hepatectomy at the National Cancer Institute, Cairo University during the period from December, 2003 to August, 2005. Eight histologically normal liver tissue samples collected from age and sex matched normal donors for liver transplant patients and four cancer cell lines (HepG2, MCF-7, HCT 116 and HeLa) were served as control.
Before surgery, all patients were subjected to complete blood picture (CBC), liver function tests (LFT), viral markers (HBs Ag and anti- HCV antibody), and preoperative serum α-fetoprotein (AFP) as well as radiological evaluation by abdominal U/S and computed tomography (CT) scan.
Diagnosis was confirmed for all cases by histopathological examination of the removed hepatectomy specimens at the Pathology department of the National Cancer Institute, Cairo University by two independent pathologists.
After surgery, all Patients were followed up for up to 95 months for disease-free (DFS) and overall survival (OS).
Cells and tissue samples were subjected to total RNA extraction using SV Total RNA Isolation System (Promega, Cat.# Z3100 ), Reverse transcription polymerase chain reaction (RT-PCR) for COX-2 expression was performed in Mx 3000P QPCR Thermocycler (Stratagene) by using Qiagen one step RT-PCR kit (Catalog no. 210212) and normalized against the expression of β2MG, housekeeping gene, as an internal control . The amplified PCR products for COX-2 and β2MG (756 bp and 116 bp respectively) were electrophoresed on 2% agarose gel (Sigma) stained with ethidium bromide (50µg/µl) and visualized under ultraviolet illumination.
The results of the present study can be summarized in the following points:
1. Cyclooxygenase-2 mRNA expression was detected in ten HCC tissues (58.8%), while the remaining seven HCC tissues were COX-2 negative (41.2%).
2. Six adjacent non-tumor liver tissues were shown to be Cyclooxygenase-2 positive (28.6%), while the other 15 adjacent non-tumor liver tissues were COX-2 negative (71.4%).
3. All normal liver tissue samples, MCF-7 cell line, HCT 116 cell line and HeLa cell lines were Cyclooxygenase-2 negative (100%), while human hepatocellular carcinoma cell line (HepG2 cell line) was Cyclooxygenase-2 positive.
4. A statistically significant association was found between the mean level of sGOT (AST) and COX-2 mRNA expression in the HCC tissues (p= 0.007).
5. However, there was no significant correlation between COX-2 mRNA expression in HCC tissues and any of the other clinicopathological and histopathological HCC patient’s characteristics.
6. There was no difference in the disease free survival (DFS) between patients expressing COX-2 in their HCC tissues and those who were negative for COX-2 expression (37 vs 38 months).
7. By studying the sensitivity and specificity of COX-2 mRNA expression in HCC, we found that COX -2 expression was 100% specific and 58.8% sensitive for the detection of HCC. While COX -2 expression was 71.4% specific and 58.8 % sensitive for disease prognosis.
8. Receiver Operating characteristic (ROC) analysis curve and the corresponding area under the curve were calculated for providing the accuracy of sGOT (s AST) levels in differentiating between HCC patients expressing COX-2 gene in their tumor tissues or not and the Roc curve values for s GOT yielded a cut off of 50 IU/L and we expect that, if the serum GOT (s AST) is > 50 IU/L the COX-2 sensitivity is 80% and specificity is 100%.