Terezinha Morato Bastos de Almeida, Regina Maria Cubero Leitão, Flair José Carrilho, Ana Maria Gonçalves da Silva and Shigueko Sonohara
Data on the onset and progression of fibrosis related to c-MYC protein expression in chronic hepatitis by C virus are scarce. In this work we evaluated by immunohistochemical method the expression of c-MYC protein in the liver parenchyma without fibrosis, and during its progression. Seventy-eight liver samples from Hepatitis C virus infected patients with different degrees of fibrosis (F0 to F4) were studied. Eleven healthy liver samples were included. All samples from chronic hepatitis were stained by hematoxylin-eosin method, and classified by METAVIR scoring system. The expression of c-MYC protein was evaluated in 1000 hepatocytes from each parenchyma area by immunohistochemistry. Results showed that c-MYC expression in hepatocytes from fibrosis samples (F1-F4) was higher, and statistically significant (P<0.05) when compared with the control group. The same results were obtained when comparing F4 vs F0; F1; F2 and F3. In contrast, the comparisons between F0 vs control; F1 vs F2; F1 vs F3; and F2 vs F3 did not present significant differences (P>0.05). In conclusion, our study showed that c-MYC protein is present in the initial degrees of fibrosis, but over-expressed in F4. This fact suggests that alteration of c-MYC expression may induce genetic instability, deregulating the cell cycle and/or apoptosis, which might contribute to progression of fibrosis and ultimately predisposing to the development of hepatocellular carcinoma.