Serum Levels of Glycosaminoglycans (GAGs) and Insulin Like Growth Factor-1 (IGF-1) as New Diagnostic Markers for Hepatocellular Carcinoma. Ahmad S. Ibrahim*, Hala A. Attia**, Ahmad M. Rabea* and Amal M. El-Gayar*. * Department of Biochemistry, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt. ** Department of Pharmacology, Faculty of Pharmacy, King Saud University, Riyadh, KSA Introduction Hepatocellular carcinoma (HCC) is one of the most common malignancies, and the death rate due to this tumor has been increasing over the past years (1). Liver cirrhosis is one of the predisposing factors leading to HCC but the mechanisms of hepato-carcinogenesis are still poorly understood. Consequently, surveillance programs based on periodic ultrasound examination and serum α-fetoprotein (AFP) determination are recommended for patients with cirrhosis (2). However, the effectiveness of these programs has not been assessed fully, and the need for new predictors for individual patients remains very high. Elevated serum AFP value in HCC patients was a common finding; however, still others had low or normal values. Because both false positive and false negative results are obtained when AFP is used as a serum marker for HCC, the search for other HCC markers is still continuous. GAGs are un-branched heteropolysaccharides found in extracellular space in multicellular organisms, where they produce a viscous extracellular matrix that resists compression (3). They are produced by fibroblasts throughout the body, mainly in synovial tissue, and are quickly cleared almost exclusively in the liver by a very efficient and specific receptor mechanism in sinusoidal endothelial cells (SEC). IGF-1 is an active somatomedin polypeptide with structural resemblance to proinsulin (4). The majority of circulating IGF-1 is produced by the liver. Fibroblasts and other cells of mesenchymal origin are the primary extra- hepatic sources of IGF-1 in vivo (5). Aim of the work The present work aimed to evaluate the significant use of serum levels of GAGs and IGF-1 as new diagnostic markers for HCC. Patients and Methods The present study was carried out on 50 patients with HCC selected from the Oncology Center, Mansoura University Hospital. Since most of HCC patients have cirrhosis, so, a group of 30 cirrhotic patients without HCC was used to nullify the effect of cirrhosis co-existence on GAGs or IGF-1 levels. Cirrhotic patients were selected from the out-patient and in- patient clinics of the Specialized Internal Medicine Hospital, Mansoura University Hospitals. The control group was comprised of 10 apparently healthy subjects. Clinical, radiological and pathological investigations were carried out in the Oncology Center and Specialized Internal Medicine Hospital. Blood samples were collected and divided into three portions: The first portion was used for blood cell counting. The second portion was collected into sodium citrate and used for determination of prothrombin time. The third portion was allowed to coagulate and centrifuged for 10 minutes at 3000 rpm. Serum was used for determination of routine liver function, AFP, GAGs and IGF-1. AFP and IGF-1 were determined using ELISA assay, while GAGs were estimated using the modified naphthoresorcinol method. Results Fig. (1): Mean serum levels of GAGs in cirrhotic and HCC patients as compared to control group. $: significance versus control group. #: significance versus cirrhotic group. Fig. (2): Mean serum levels of IGF-1 in cirrhotic and HCC patients as compared to control group. $: significance versus control group. #: significance versus cirrhotic group. Table (1): Serum AFP in HCC patients as compared to control (Mean ± SEM). Groups Serum AFP (ng/ml) Control group (n=10) 5.99 ± HCC patients With normal serum AFP (<15 ng/ml) (n=10) ±1.6 With AFP levels ng/ml (n=18) $ ± With AFP levels >400 ng/ml (n=22) $* ± $: significance versus control group. *: significance versus HCC patients with AFP levels ng/ml. Groups IGF-1 (ng/ml) Control group ± 12.2 HCC patients with normal AFP levels 17.4 $ ± 4 HCC patients with AFP levels ng/ml 22.8 $ ± HCC patients with AFP > 400 ng/ml 24.7 $ ± 4.57 Table (2): Serum IGF-1 level in HCC patients with normal AFP levels, those with AFP ( ng/ml) and those with AFP> 400 ng/ml. Discussion &Conclusions The significant increase in GAGs level in both cirrhotic and HCC patients (Fig.1) may be due to the impairment of SEC receptor removal of GAGs. SEC dysfunction may result in increased deposition of extracellular matrix. Since GAGs level may increase in other diseases such as inflammatory and rheumatologic conditions, the combined measurement of serum levels of GAGs and IGF-1 provide a more sensitive marker for liver diseases. In opposite to other malignancies such as prostate (6), breast (7) and colorectal cancer (8), IGF-1 levels reduced significantly in HCC patients (Fig. 2) reflecting the possible specificity of IGF- 1 for HCC. 10 HCC patients had normal serum AFP level (Table 1). Serum IGF-1 in those patients was decreased significantly from the control (Table 2) suggesting that, serum IGF-1 may be an important marker for the diagnosis of HCC, particularly in those patients with low level of serum AFP. References 1- Aizawa, Y. et al. Cancer, 2000; 89: Briux, I et al. J. Hepatol., 2001; 35: Zubay, G. (1998): Biochemistry. Wm. C. Brown Publishers; London, p Rinderknecht, E. and Humbel, R.E Proc. Natl. Acad. Sci. USA,1976; 73:2365–9. 5- LeRoith, D. N. Engl. J. Med., 1997; 336:633– Chan, J.M et al. Science,1998 ; 279: Hankinson, S.E. et al. Lancet., : Ma, J.; Giovanucci, E.; Pollak, M.N. and Stampfer, M.J. J. Natl. Cancer Inst., $: significance versus control group.