Το ουροθηλιακό καρκίνωμα προέρχεται από το ουροθήλιο το οποίο αντιστοιχεί στο επιθήλιο που επενδύει την ουροφόρο οδό. Αποτελεί έναν από τους συχνότερους καρκίνους του ανθρώπου καταλαμβάνοντας την 5η θέση μεταξύ όλων των καρκίνων στο δυτικό κόσμο. Οι σημαντικότεροι παράγοντες κινδύνου για την ανάπτυξη ουροθηλικού καρκινώματος είναι το κάπνισμα και η επαγγελματική έκθεση σε αρωματικές αμίνες. Τα ουροθηλιακά καρκινώματα διακρίνονται σε δύο φαινοτυπικές ποικιλίες με διαφορετική βιολογική συμπεριφορά και πρόγνωση αλλά και διαφορετικούς μηχανισμούς ανάπτυξης. Έτσι έχουμε τα χαμηλού βαθμού κακοήθειας νεοπλάσματα και τους διηθητικούς όγκους (υψηλού βαθμού κακοήθειας). Επιπλέον, ιδιαίτεροι παθογενετικοί μηχανισμοί χαρακτηρίζουν τα ουροθηλιακά νεοπλάσματα της ανώτερης ουροφόρου οδού. Στα χαμηλού βαθμού κακοήθειας νεοπλάσματα τα οποία προέρχονται από υπερπλαστικές αλλοιώσεις συναντάμε μεταλλάξεις των υποδοχέων FGFR3 και EGFR καθώς και του ογκογονιδίου H-RAS με αποτέλεσμα την ενεργοποίηση του μονοπατιού των RAS-MAP κινασών. Στους υψηλού βαθμού κακοήθειας (διηθητικους) όγκους οι οποίοι αναπτύσσονται de novo ή προέρχονται από καρκίνωμα in situ συναντάμε μεταλλάξεις των ογκογονιδίων p53, RB και p57. Επιπλέον χαρακτηρίζονται από υπερέκφραση της αντιαποπτωτικής πρωτεϊνης survivin, των καβεολινών 1 και 2, της COX-2, των μεταλλοπρωτεϊνασών και των επαγωγέων της αγγειογένεσης VEGF, VEGFR και bFGF, καθώς και από διαταραχή της έκφρασης των μορίων του κυτταροσκελετού. Τέλος έχει βρεθεί υπερέκφραση του παράγοντα OCT-4, ρυθμιστή της αυτοανανέωσης και της διαφοροποίησης στα εμβρυϊκά stem κύτταρα, δικαιώνοντας τη θεωρία των καρκινικών stem κυττάρων. Η απώλεια ετεροζυγωτίας του χρωμοσώματος 9 παίζει επίσης σημαντικό ρόλο στη ανάπτυξη ουροθηλιακών καρκινωμάτων και θεωρείται ότι εμπλέκεται στα πρώιμα στάδια της ογκογένεσης απαντώμενη έτσι και στις δύο φαινοτυπικές ποικιλίες. Αντίθετα, τα ουροθηλιακά νεοπλάσματα της ανώτερης ουροφόρου οδού χαρακτηρίζονται από ένα είδος γενετικής αστάθειας, την αστάθεια των μικροδορυφόρων. Η καλύτερη κατανόηση των παθογενετικών μηχανισμών ανάπτυξης των ουροθηλιακών καρκινωμάτων θα συμβάλλει τόσο στη δημιουργία νέων και αποτελεσματικότερων φαρμάκων όσο και στην εύρεση νέων μοριακών δεικτών. Ο προσδιορισμός τέτοιων βιολογικών δεικτών, θα βελτιώσει το screening και τη διάγνωση και θα βοηθήσει στον καλύτερο προσδιορισμό του κακοήθους δυναμικού αλλά και της πρόγνωσης των ουροθηλιακών καρκινωμάτων. / Urothelial cancer derives from urothelium which is the epithelium lining the urinary tract. It is one of the most frequent human cancers occupying the 5th position among all cancers in the Western World. The most important risk factors for the development of urothelial cancer are smoking and occupational exposure to aromatic amines. Urothelial cancers are divided into two dinstict categories according to their biological behaviour and pathogenetic background: low grade neoplasms and high grade tumors (infiltrative). Interestingly, the neoplasms of the upper urinary tract have a distinct pathogenetic mechanism. Low grade urothelial carcinomas, known to derive from hyperplastic lesions, have been found to bear mutations of the FGFR3 and EGFR receptors as well as of the H-RAS oncogene which leads to the activation of the RAS-MAPK signal transduction pathway. High grade tumors may develop de novo or they may derive from carcinoma in situ. They are commonly characterized by mutations of the oncogenes p53, Rb and p57. Additionaly, in high grade urothelial carcinomas there is overexpression of the antiapoptotic protein survivin as well as caveolin1 and 2, COX-2, metalloproteases and angiogenetic factors such as VEGF, VEGFR and bFGF. There is also disrupted expression of the cytoskeleton’s molecules. Overexpression of the transcription factor OCT-4, a regulator of self renewal and differentiation of embryonic stem cells, has been also recently reported. Loss of heterozygosity of chromosome 9 plays an important role in the development of urothelial cancer and it is considered to be implicated in the early steps of oncogenesis. In contrast, urothelial cancers of the upper urinary tract have been associated with microsatellite instability, an indicative marker of genomic instability. Elucidating the pathogenesis of urothelial cancersmay contribute to the development of novel and more effective anticancer treatments as well as to the identification of new biological markers with prognostic significance.

Purpose: To determine the expressions of bcl-2, p53, Ki-67 and PTEN on the basis of immunohistochemistry methods in upper urinary transitional cell carcinoma (TCC), and to correlate their presentations in specimens with clinical tumor stage, grade and patient survival. Material and Method: Paraffin-embedded primary upper urinary TCC specimens were divided into 2 groups for immunohistochemical study: Group 1 including 91 cases were treated with bcl-2, p53 and Ki-67 antibodies; group 2 including 93 specimens contained both tumor and benign tissues were treated with PTEN antibody. Semi- quantitatively, according to the amount of the stained cells, they were divided into 3 levels: level 1, scanty; level 2, focal; and level 3, diffuse. Association of immunoreactivity with tumor grade and stage was examined. Prognostic significance of tumor marker expression in patients¡¦ survival was accessed. Results: Group1: Of the 91 tumors most (98.9%) of the specimens showed level 1 bcl-2 expression and only 1 patient had level 2 expression. The p53 mutations were identified level 3 expression in 48.4% of the cases, followed by level 2 (26.4%) and level 1 (25.3%) identifications. The Ki-67 expression was recognized level 3 in 6 patients, level 2 in 21 and level 1 in 66 cases. Significant correlations were seen between p53 expression and tumor grading (p=0.004) and between immunostain of Ki-67 and clinical stage (p=0.031). The p53, bcl-2 and Ki-67 expressions in upper urinary tract TCC specimens were not a significant factor of patients¡¦ survival. Group 2: Of the tumors all cytoplasm has level 3 PTEN expressions and the nuclei, 18 (19.4%) showed scanty expression, 35 (37.6%) revealed focal expression, and diffuse expression was noted in 40 (43.0%) cases. Loss of PTEN expression in tumor nuclei was positively correlated with pathologic stage (p=0.019). Of the fibrocytes adjacent to tumor cells, the nuclei showed 24 (25.8%) scanty, 59 (63.4%) focal and 10 (10.8%) diffuse distribution of PTEN expressions. Poorly differentiated tumor (grade 3) specimens were correlated with loss of PTEN expression in fibrocytic nuclei adjacent to tumor (p=0.028). Most (58%) fibrocytic cytoplasm was scanty PTEN expression, followed by 23 (24.7%) diffuse and 16 (17.2%) focal immunostaining. PTEN expressions in upper urinary tract TCC specimens were not a significant factor of patients¡¦ survival. Conclusions: We examined 93 surgical specimens of upper urinary tract TCC for the expression of PTEN and 91 cases for bcl-2, p53 and Ki-67 by immunohistochemical stained. Correlation between tumor grading and p53 mutations and correlation between clinical stage and Ki-67 immunoreactivity were observed. Meanwhile, loss of PTEN expression in tumor nuclei of upper urinary TCC is correlated significantly with advanced tumor stage, and poorly differentiated tumor specimens were correlated with loss of PTEN expression in normal nuclei adjacent to tumor cells. However, no correlation between overall survival rate and tumor markers was identified. Thus, the detection of p53, bcl-2, Ki-67 and PTEN would be not enough for evaluation the prognosis of upper TCC.

Affibodymolekyler är små affinitetsproteiner (6.5 kDa) som föreslås kunna ersätta monoklonala antikroppar i terapeutiska tillämpningsområden, exempelvis i antikropp-läkemedelskonjugat (ADCs) som kan navigera sig fram till biomarkörer som är uttryckta på cancerceller. Affibody-läkemedelskonjugat (AffiDC) kan användas för att målsöka just sådana överuttryckta proteiner, samtidigt som de erbjuder goda egenskaper, såsom snabb transportering och spridning i kroppen, och effektiv penetrering genom tumörer. Dessa AffiDC:er skulle kunna användas inom riktad cancerterapi for de cancersjukdomar som fortfarande är i behov av cancerhämmande behandlingar, såsom urotelial cancer.  Den här studien föreslog tillämpning av ABD-kopplade affibodymolekyler för att målsöka ett nytt målprotein som har visats vara överuttryckt i flera olika cancersjukdomar, exempelvis bröst-, pankreas- och urotelial cancer. Affibodykandidater mot målproteinet har valts ur ett rekombinant bibliotek med 1×1011 transformanter som uttrycks med hjälp av en så kallad metod med E. coli celldisplay där affibodymolekylen visas på cellens ytmembran. De slutliga kandidaterna var sedan identifierade och biokemiskt karaktäriserade i in vitro-studie på människoceller, som visade att två av kandidaterna verkade binda till cancercellinjerna BT-474 och MCF-7 med KD omkring 10 till 100 nM. / Affibody molecules are small affinity proteins (6.5 kDa) suggested to substitute monoclonal antibodies in therapeutic applications, e.g., antibody-drug conjugates (ADCs) targeting biomarker proteins expressed on cancer cells. An affibody-drug conjugate (AffiDC) could be used to target these types of overexpressed proteins on cancer cells while offering attractive properties, such as rapid transportation and distribution in the body, as well as efficient tumour penetration. These AffiDCs could be used as a targeted cancer therapy for cancers that are yet to be treatable and curable, like urothelial cancers.  This study suggested the use of ABD-fused affibodies to target a novel cancer protein that has been shown to be overexpressed on cancer cells, including breast, pancreatic and urothelial cancer. Affibody candidates toward this novel target were selected from a recombinant library, of 1×1011 transformants, that is expressed using E. coli cell display system. The final candidates were subsequently biochemically characterized and assessed for affinity for the target. Three affibodies were finally identified and assessed in in vitro studies on mammalian cells, revealing two affibodies that appear to bind to the cell lines BT-474 and MCF-7 with KD ranging 10 to 100 nM.

Aristolochic acids (AA) are human carcinogens which have also very strong nephrotoxic properties. A mixture of AA is present in Aristolochiacae plant species. These plants were and still are used in traditional medicine in some countries, particularly in Asia. Aristolochic acids participate in development of two types of nephropathies. The first disease is designated as Aristolochic Acid Nephropathy (AAN), the second one is Balkan Endemic Nephropathy (BEN). Both nephropathies are associated with urothelial malignancies, which are caused by AA. One of the common features of ANN and BEN is that not all individuals exposed to AA suffer from nephropathy and tumour development. One cause for these different responses may be individual differences in the activities and expression levels of the enzymes catalyzing the biotransformation of AAI, the major toxic component of AA contained in Aristolochia species. Detailed knowledge of enzymes which participate in metabolism of AAI may contribute to elucidation of inter-individual susceptibility to AAN, BEN and later urothelial malignancies. Aristolochic acid I is either oxidative detoxicated or reductive activated by biotransformation enzymes. Reductive bioactiovation of AAI leads to formation of covalent AA-DNA adducts in organism which result in producing of...

Aristolochic acids (AA) have been considered as toxicants of plants which were found in plants of the family Aristolochiaceae. The most abundant acids in mentioned plants are aristolochic acid I (AAI) and aristolochic acid II (AAII). AA have been considered as causes kidney disease called Aristolochic acid nephropathy (AAN). AAN was initially discovered in patients of one Belgian clinic in Brussels specialized on treatment of patients leading to a decrease in their body weight. The first name of this disease was Chinese herb nephropathy (CHN). Later, it was discovered that one component of herbal preparation was changed by a mistake with the Aristolochiaceae plant. The second type of renal disease caused by AA was discovered in populations of countries along the Danube river, called as Balkan endemic nephropathy (BEN), which was probably caused by the contamination of grains with plants containing AA. These renal diseases (AAN and BEN) are often associated with development of upper urothelial cancer (UUC). AA (AAI + AAII) in organisms are subject to biotransformation leading to its reductive activation or oxidative detoxification. Both cytosolic enzymes [NAD(P)H:quinone oxidoreductase] and microsomal enzymes [cytochromes P450, NADPH:cytochrome P450 reductase] participate in their reduction. The...