| Introduction: Bladder cancer is the 5th most common malignancy and the 4th leadingcause of cancer death of men in the United States. Clinically, the most important distinctionis that between papillary and invasive TCCB. Papillary cancers typically exhibit activationof the MAPK pathway, as a consequence of oncogenic mutations in FGFR3 or H-ras, withincreased Cyclin D1 expression. In the other way, invasive TCCB are characterized bysevere disturbances in proximate cell cycle regulators, e.g. Rb1 and CDKN2A/p16INK4A,which decrease dependency on mitogenic signaling. In addition, these disturbances permit,promote and are in turn exacerbated by chromosomal instability, which is further enhancedby loss of TP53 function. Intriguingly, neither canonical WNT/b-Cateninn nor hedgehogsignaling appear to play major roles in TCCB. This may reflect its origin from moredifferentiated urothelial cells possessing a high regenerative potential rather than a stem cellpopulation.Like urothelia, keratinocytes is not directly originated from stem cells and bothWNT and hedgehog signaling which have important crosstalk with Notch family are notactive. Notch factors in keratinocytes act as tumor suppressors, which is quite differentfrom other tumors. It inspired us to investigate the function of Notch family in TCCB.Notch signaling participates in the development by maintaining the self-renewalpotential of some tissues and can positively or negatively influence proliferation,differentiation, and apoptosis depending on the cell types. To date, 4 Notch receptors havebeen identified (Notch 1-4) in humans, with corresponding ligands including Delta-like-1,Delta-like-3, Delta-like-4, Jagged-1 and Jagged-2. Involvement of Notch in cancer was firsthighlighted in human T-cell leukaemia, fuelling the notion that aberrant Notch signalingpromotes tumorigenesis. However, there is mounting evidence that Notch signaling is notexclusively oncogenic. It can instead function as a tumor suppressor in the skin. Theseapparently contradictory functions of Notch signaling strongly indicate that the outcome ofNotch activation is dependent on the cellular context. To date, the Notch pathway has been rarely associated with TCCB. In this study, theexpression of Notch ligands and receptors was detected in normal and tumorous humanbladder transitional epithelia, respectively. The relationship between the expression patternof them and prognosis of bladder cancer patient was also evaluated.MATERIALS AND METHODS: Patients and Tissue Samples: Fresh tumor tissuesnap-frozen in liquid nitrogen in the operating room was obtained from single hospitalbetween January 2000 and December 2006. All tumors were primary and diagnosedaccording to the WHO/ISUP classification of urothelial tumors and staged according to theTNM system as TaG1 in 35, T1G2 in 2, T2G2 in 16 and T3G3 in 17. These tissues werefrom 41 men and 29 women with the mean age at diagnosis being 59 years old (range 28 to75). None of them had received any preoperative therapy. For comparison, 10 cases ofnormal urothelia were obtained from surgical specimens. The pathological characteristics ofthese urothelia were confirmed by hematoxylin and eosin staining.Immunohistochemical staining: Section preparation andimmunostaining were done aspreviously described. Two observers evaluated the staining pattern of the protein separatelyand scored each specimen for the percentage of positive cells identified. An average of 20fields was observed for each specimen. The immunoreactivity of a tissue sample wasconsidered negative (-) if less than 10% of the cells showed the same staining intensity asthe positive control in arterial endothelia, low expression level (+) if 11%-20% of the cellsshowed the staining above, medium expression level (++) if 21%-60% of the cells showedthe staining above and high expression level (+++) if more than 60% of the cells showedthe staining above.Total RNA was extracted with TRIzol (Invitrogen) reagent. Two-step RT-PCR wascarried out in 25μl volume on indicated amounts of RNA by use of a gene specific primer.Western Blotting: Protein levels were determined by the Bradford assay. Protein extractswere mixed with SDS sample buffer and electrophoresed in 10%. The signals werevisualized with the ECL system (DuPont NEN, Wilmington DE, USA).Statistical Analyses: The association between the expression of Notch factors intumors and the various clinicopathological variables was examined using the chi-square testor Fisher's exact test. Mann-Whitney U test was performed for continuous variables.Survival analyses were conducted according to the Kaplan-Meier method and survival characteristics were compared using log rank tests. Disease-flee survival was defined as theperiod between surgery and the detection of initial local recurrence, distant metastasis orstudy end. The Cox proportional hazards regression model was used to compare the relativeinfluences of different prognostic factors. The statistical software package SPSS 11.0 (SPSS,Inc., Chicago, Illinois) was used for all statistical analyses, with p＜0.05 indicatingstatistical significance.RESULTS: In the present study tumors were divided into 2 groups of papillary (pTa)and invasive (pT1-pT3), respectively. All of the 5 kinds of Notch factors were intensivelystained in normal bladder transitional epithelia, but their expression was significantlydecreased in tumor tissues. Moreover, the expression level of the 5 proteins in the papillarytumors was lower than that in the invasive tumors (P＜0.05). In tumor cells, the immuneactivity of Notch factors was observed on the membranes of papillary tumor cells, while itbecame diffused and turned to cytoplasm in invasive ones. The expression of Notch factorswas not related with patients' age at diagnosis, sex, vascular invasion or lymph nodeinvolvement. No differences in immune activity of all the antibodies were found betweenthe basal cell layer and papillary layer of urothelia.To further confirm the IHC results, the tissue samples were subjected to RT-PCR andWestern blot analysis. The papillary tumors showed weak immunoreactive bands of theexpected Notch factors molecular weight in western blot, whereas the normal and invasivetissues had intense expression. Among the three groups, each two of them had statisticaldifference.Kaplan-Meier analyses revealed that the decreased expression of Notch-1 and Jagged-1was associated with an increased disease-free survival in papillary TCCB (p = 0.024 and0.003 respectively). Survival time of patients with low expression of both Notch-1 andJagged-1 was significantly shorter than that with other expression patterns in papillarytumors (p = 0.002). The expression pattern of other Notch factors was not correlated withthe survival time of the patients with invasive or all types of TCCB.CONCLUSION: There are two expression patterns of Notch family in TCCB betweenpapillary and invasive tumors. The expression of Notch-1 and Jagged-1 is correlated withdisease-survival of papillary TCCB patients. BACKGROUND: Tuberculous ureteral obstruction is a major cause of progressiveuropathy commonly complicates renal tuberculosis. The effect of chemotherapy andconcomitant fibrosis compounds the problem and results in renal loss. The possible benefitof early ureteral stenting in patients with renal tuberculosis is uncertain.METHODS: We performed a multicenter, randomized clinical trial on patients withrenal tuberculosis comparing the efficacy of medication only with medication plus earlyureteral stenting. The lest follow-up period was 2 years. The primary outcome was the timeof glomerular filtration rate (GFR) reduced to 10 ml/min.RESULTS: A total of 298 patients were randomly assigned to undergo either themedication only management or the early ureteral stenting procedure. The renal functioncould be better preserved by early ureteral stenting (P= 0.012). The rate of treatment failurewas lower in patients who underwent the early ureteral stenting procedure than in thosereceiving medication only (P= 0.001). After the first 4 week's of assignment, patientssubject to early ureteral stenting procedure had higher scores on the Medical OutcomesStudy 36-Item Short-Form General Health Survey questionnaire (P = 0.003).CONCLUSIONS: Early ureteral stenting in patients with renal tuberculosis wasbeneficial to preservation of renal function, decreased the possibility of renal loss andimproved life quality.
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