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INTRODUCTION: Overexpression of epidermal growth factor receptor (EGFR) has been described in several solid tumors including bladder cancer. Transforming growth factor alpha (TGFα) is frequently deregulated in neoplastic cells and plays a role in the development of bladder cancer. TGFα-EGFR ligand-receptor combination constitutes an important event in multistep tumorigenesis. METHODS: This study was done on 30 bladder biopsies from patients with urothelial carcinoma, 15 with squamous cell carcinoma, 10 with cystitis and 5 normal control bladder specimens. All were immuohistochemically stained with EGFR and TGFα antibodies. RESULTS: EGFR and TGFα were over-expressed in higher grades and late stages of bladder cancer. Moreover, they show higher expression in squamous cell carcinoma compared to urothelial carcinoma and in schistosomal associated lesions than in non-schistosomal associated lesions. CONCLUSION: EGFR and TGFα could be used as prognostic predictors in early stage and grade of bladder cancer cases, especially those with schistosomal association. In addition they can help in selecting patients who can get benefit from anti-EGFR molecular targeted therapy.
RESUMO
BACKGROUND: Praziquantel (PZQ) is an isoquinoline derivative (2-cyclohexylcarbonyl-1, 2, 3, 6, 7, 11b-hexahydro-4H-pyrazino{2,1-a}-isoquinoline-4-one), and is currently the drug of choice for all forms of schistosomiasis. Silymarin, a standardized milk thistle extract, of which silibinin is the main component, is known for its hepatoprotective, anti-inflammatory, antioxidant activities, and hepatocyte regeneration. This study investigates the anti-inflammatory/anti-fibrotic effects of silymarin and/or PZQ on schistosomal hepatic fibrosis. METHODS: Schistosoma mansoni-infected mice were divided into two large groups (I & II), each with four subgroups and were run in parallel. (i) Infected untreated; (ii) treated with silymarin, starting from the 4th (3 weeks before PZQ therapy) or 12th (5 weeks after PZQ therapy) weeks post infection (PI); (iii) treated with PZQ in the 7th week PI; and (iv) treated with silymarin, as group (ii) plus PZQ as group (iii). Comparable groups of uninfected mice run in parallel with the infected groups. Mice of groups I and II were killed 10 and 18 weeks PI, respectively. Hepatic content of hydroxyproline (HYP), serum levels and tissue expression of matrix metalloproteinase-2 (MMP-2), transforming growth factor-ß1 (TGF-ß1) and number of mast cells were determined. In addition, parasitological, biochemical and histological parameters that reflect disease severity and morbidity were examined. RESULTS: Silymarin caused a partial decrease in worm burden; hepatic tissue egg load, with an increase in percentage of dead eggs; modulation of granuloma size, with significant reduction of hepatic HYP content; tissue expression of MMP-2, TGF-ß1; number of mast cells, with conservation of hepatic reduced glutathione (GSH). PZQ produced complete eradication of worms, eggs and alleviated liver inflammation and fibrosis. The best results were obtained, in most parameters studied, in groups of mice treated with silymarin in addition to PZQ. CONCLUSIONS: Our results point to silymarin as a promising anti-inflammatory and anti-fibrotic agent; it could be introduced as a therapeutic tool with PZQ in the treatment of schistosomal liver fibrosis, but further studies on mechanisms of silymarin and PZQ in chronic liver diseases may shed light on developing therapeutic methods in clinical practice.