Heme oxygenase-1 in colorrectal carcinoma

GONZALEZ DONNA M.L.; GANDINI N.A.; ANDRÉS N.C.; FERRO A.; SALOMÓN D.G.; FERMENTO M.E.; GRIOLI S.; FACCHINETTI M.M.; CURINO A.C.

Barcelona

Conferencia; ESMO conference 12th Word Conference on Gastrointestinal Cancer; 2010

European Society for Medical Oncology

Background: Similar histopathologically classified tumors in colorrectal cáncer (CRC) show important differences in disease progression and response to treatment, thus reflecting the need to find new molecular targets for therapeutic intervention. An increasing amount of evidence indicates that heme oxygenase-1 (HO-1) activation may play a role in carcinogenesis and can potently influence the growth and metastasis of tumors. The aim of this work was to study the expression of HO-1 in human metastatic CRC biopsies and try to define its role in CRC using an animal model. Methods: Immunohistochemistry for HO-1 was performed in tissue samples from 35 patients with metastatic CRC. Results: We found positive staining in 76% of specimens and protein expression was stronger in tumor than in non-malignant adjacent areas (p=0.02). HO-1 immunoreactivity was observed in apical cells within the normal epithelia, being basal cells devoid of HO-1 staining. In order to better study the significance of HO-1 in CRC, we assessed the expression of HO-1 in tissue samples from 30 Wistar rats induced with 1,2-dimethylhydrazine. Normal epithelia, polyps and carcinoma tissues were obtained at different times of disease progression. We found positive staining in 15/15 (100%) of carcinoma specimens and protein expression showed similar immunostaining localization as the human samples. We also performed Western Blot for HO-1, and observed an increase in the expression of the protein with the progression of the disease. Conclusions: Our results corroborate higher rates of HO-1 protein expression in human CRC than in normal epithelia and show an increase in HO-1 expression with malignant progression.