Background: Stem cell injection therapies have been proposed to overcome the limited efficacy and adverse reactions of bulking agents. However, most have significant limitations, including painful procurement, requirement for anesthesia, donor site infection and a frequently low cell yield. Recently, human amniotic fluid stem cells (hAFSCs) have been proposed as an ideal cell therapy source. In this study, we investigated whether periurethral injection of hAFSCs can restore urethral sphincter competency in a mouse model. Methods: Amniotic fluids were collected and harvested cells were analyzed for stem cell characteristics and in vitro myogenic differentiation potency. Mice underwent bilateral pudendal nerve transection to generate a stress urinary incontinence (SUI) model and received either periurethral injection of hAFSCs, periurethral injection of Plasma-Lyte (control group), or underwent a sham (normal control group). For in vivo cell tracking, cells were labeled with silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate (MNPs@SiO2 (RITC)) and were injected into the urethral sphincter region (n = 9). Signals were detected by optical imaging. Leak point pressure and closing pressure were recorded serially after injection. Tumorigenicity of hAFSCs was evaluated by implanting hAFSCs into the subcapsular space of the kidney, followed two weeks later by retrieval and histologic analysis. Results: Flow activated cell sorting showed that hAFSCs expressed mesenchymal stem cell (MSC) markers, but no hematopoietic stem cell markers. Induction of myogenic differentiation in the hAFSCs resulted in expression of PAX7 and MYOD at Day 3, and DYSTROPHIN at Day 7. The nanoparticle-labeled hAFSCs could be tracked in vivo with optical imaging for up to 10 days after injection. Four weeks after injection, the mean LPP and CP were significantly increased in the hAFSC-injected group compared with the control group. Nerve regeneration and neuromuscular junction formation of injected hAFSCs in vivo was confirmed with expression of neuronal markers and acetylcholine receptor. Injection of hAFSCs caused no in vivo host CD8 lymphocyte aggregation or tumor formation. Conclusions: hAFSCs displayed MSC characteristics and could differentiate into cells of myogenic lineage. Periurethral injection of hAFSCs into an SUI animal model restored the urethral sphincter to apparently normal histology and function, in absence of immunogenicity and tumorigenicity.
New biological prognostic predictors have been studied; however, some factors have limited clinical application due to tissue-specific expression and high cost. There is the need for a promising predictive factor that is simple to detect and that is closely linked to oncological outcomes in patients with urothelial bladder cancer (BC) who have undergone radical cystectomy (RC). Therefore, we investigated the clinical prognostic value of the preoperative De Ritis ratio (aspartate aminotransferase/alanine aminotransferase) on oncological outcomes in patients with urothelial BC after RC. We retrospectively evaluated clinicopathological data of 118 patients with non-metastatic urothelial BC after RC between 2008 and 2013 at a single center. The association between the De Ritis ratio and clinicopathological findings was assessed. The potential prognostic value of the De Ritis ratio was analyzed using the Kaplan-Meier method, and multivariate Cox analyses were performed to identify the independent predictors of metastasis-free survival, cancer-specific survival, and overall survival. According to the receiver operating curve of the De Ritis ratio for metastasis, we stratified the patients into 2 groups using a threshold of 1.3. A high De Ritis ratio was more likely to be associated with old age and the female sex. Kaplan-Meier estimates revealed that patients with a high De Ritis ratio had inferior metastasis-free survival, cancer-specific survival, and overall survival outcomes (P = 0.012, 0.024, and 0.022, respectively). Multivariate analysis revealed that a high De Ritis ratio was an independent prognostic factor for metastasis (hazard ratio [HR], 2.389; 95% confidence interval [CI], 1.161–4.914; P = 0.018), cancer-related death (HR, 2.755; 95% CI, 1.214–6.249; P = 0.015), and overall death (HR, 2.761; 95% CI, 1.257–6.067; P = 0.011). An elevated De Ritis ratio was significantly associated with worse prognosis in patients who underwent RC for urothelial BC. This ratio might further improve the predictive accuracy for prognosis in BC.