IMP3 expression in urothelial carcinomas of the urinary bladder

Objective: Superficial tumors including Ta, Tis, and T1 make up 75% of urothelial carcinomas of the bladder. While the behavior of these superficial urothelial cancers is relatively benign, invasive tumors have a significant mortality rate. However, Ta and T1 tumors might display different biological behavior. There is therefore a great need for biomarkers that can accurately distinguish the behavior of urothelial carcinomas in addition to tumor grade and stage. Our aim was to determine the immunohistochemical expression profile of insulin like growth factor II mRNA binding Protein 3 (IMP3) and its correlation with tumor stage and grade in benign urothelium and bladder urothelial carcinomas. Material and Method: The expression of IMP3 in 91 patients with benign urothelium (20 cases), low grade invasive (17 cases) / noninvasive (20 cases) urothelial carcinoma and high grade invasive (20 cases) / non-invasive (14 cases) urothelial carcinoma was evaluated by immunohistochemistry in this study. Results: IMP3 was not expressed in benign urothelium, low-grade non-invasive urothelial carcinoma and high grade non-invasive urothelial carcinoma. Expression of IMP3 was found in 11.76% of low-grade invasive urothelial carcinomas and 55% of high grade invasive urothelial carcinomas. Statistical analysis including χ2 tests showed that IMP3 expression of invasive urothelial carcinomas was statistically significant (p<0.000). Conclusion: The detection of IMP3 only in invasive carcinomas although some of them were low grade showed that the expression of IMP3 may be related to aggressive behavior of urothelial carcinomas

Benign ürotelyum ile düşük ve yüksek dereceli invaziv/non-invaziv ürotelyal karsinomlarda IMP3 ekspresyon profilinin belirlenmesi, tümör evresi ve diferansiyasyon derecesi ile korelasyonun saptanması

Urothelial carcinoma is the most common type of urinary bladder cancer and accounts for about 95% of malignant bladder tumors. Identification of prognosis and treatment of urothelial cancers are mainly based on the tumor grade and stage. However, the biological behavior of the same stage tumors may be significantly different. None of the markers used in urothelial carcinoma related studies have been adopted in clinical practice. IMP3 is an oncofetal protein which is a member of insulin-like growth factor (IGF)-II mRNA binding protein family. Several studies have shown that IMP3 is associated with aggressive tumors in various organs including bladder.In this study, the expression of IMP3 in 91 patients with benign urothelium (20 cases), low grade invasive (17 cases) / non-invasive (20 cases) urothelial carcinoma and high grade invasive (20 cases) / non-invasive (14 cases) urothelial carcinoma was evaluated by immunohistochemistry. Our study shows that IMP3 is not expressed in benign urothelium, low-grade non-invasive urothelial carcinoma and high grade non-invasive urothelial carcinoma. Expression of IMP3 was found in 11.76% of low-grade invasive urothelial carcinomas and 55% of high grade invasive urothelial carcinomas. According to these data, statistical analysis including ?2 tests showed that IMP3 expression of invasive urothelial carcinomas were statistically significant (p0.000).Our results were similar with literature and showed that the expression of IMP3 may be related to aggressive behavior of urothelial carcinomas.Ürotelyal karsinom mesanede en sık görülen kanser tipi olup, malign mesane tümörlerinin yaklaşık %95'ini oluşturur. Mesane tümörlerinin prognozunu ve tedavi şemasını belirlemede en önemli iki etken histolojik evre ve derecedir. Bununla birlikte, aynı evre tümörlerin biyolojik davranışları anlamlı derecede farklı olabilmektedir. Ürotelyal karsinomla ilgili çalışmalarda kullanılan belirteçlerin hiçbirisi, klinik uygulamaya geçirilememiştir. IMP3, insülin-like growth factor (IGF)-II m-RNA bağlayıcı protein ailesine ait bir onkofetal proteindir. Mesane de dahil çeşitli organlarda yapılan birçok çalışmada IMP3, agresif tümörlerle ilişkili bulunmuştur.Bu çalışmada 91 hastaya ait benign ürotelyum (20 olgu), düşük dereceli invaziv (17 olgu) / non-invaziv (20 olgu) ürotelyal karsinom ve yüksek dereceli invaziv (20 olgu) / non-invaziv (14 olgu) ürotelyal karsinom tanısı almış olgular immünohistokimyasal olarak IMP3 ekspresyonu açısından değerlendirildi. Benign ürotelyum, düşük dereceli non-invaziv ürotelyal karsinom ve yüksek dereceli non-invaziv ürotelyal karsinom tanısı almış olgularda IMP3 ekspresyonu saptanmadı. Düşük dereceli invaziv ürotelyal karsinom olgularının %11,76'sında, yüksek dereceli invaziv ürotelyal karsinom olgularının %55'inde IMP3 ekspresyonu saptandı. Bu verilere göre ?2 testi ile yapılan istatistiksel analizde, invaziv tümörler ile IMP3 ekspresyonu arasında anlamlı ilişki saptandı (p0.000).Bulgularımız, literatür ile benzer şekilde olup, IMP3 ekspresyonunun ürotelyal karsinomlarda agresif tümör davranışı ile ilişkili olabileceğini düşündürmektedir