Prognosis of rare pathological primary urethral carcinoma

Mierxiati Abudurexiti,1,2,* Jun Wang,1,2,* Ning Shao,1,2 Fang-Ning Wan,1,2 Yao Zhu,1,2 Bo Dai,1,2 Ding-Wei Ye1,2 1Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China; 2Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China *These authors contributed equally to this work Purpose: Urethral carcinoma (UC), as a rare tumor, is not widely studied. There have been no systematic studies of rare pathological types of UC. We conducted this study to further investigate rare pathological types of primary urethral carcinoma (PUC).Materials and methods: We used the population-based Surveillance, Epidemiology, and End Results (SEER) database to evaluate prognostic factors in rare pathological types of PUC. From 1978 to 2015, 2,651 and 257 cases were identified in the SEER database as common and rare pathological types of PUC, respectively. Overall and cancer-specific survival (CSS) times were computed using the Kaplan–Meier method, and the Cox proportional hazards analysis was used to evaluate patient age at diagnosis, gender, race, and TNM stage.Results: The median overall survival (OS) rates were 36 and 59 months for rare and common pathological groups, respectively, and their respective 10-year OS rates were 31.9% and 42.4%, respectively. The median CSS rate was 61 months for the rare pathological group. Through multivariate analysis, it was found that age, race, T stage, and M stage were independent prognostic risk factors for rare pathological type of urethral cancer. In the age group, the HR ratio of patients aged older than 60 years and younger or equal to 60 years was 2.778 (P<0.001). The HR ratio of other races to Whites was 1.444 (P=0.040). In TNM staging, the HR ratio between T3–T4 and Ta–T2 was 2.386 (P=0.046), and the HR value of M1 and M0 was 5.847 (P<0.001).Conclusion: Age, race, T stage, and M stage were predictive of OS and CSS in rare pathological PUC. Keywords: urethral cancer, SEER, age, race, TN

Bio-inspired nanocarriers derived from stem cells and their extracellular vesicles for targeted drug delivery

With their seemingly limitless capacity for self-improvement, stem cells have a wide range of potential uses in the medical field. Stem-cell-secreted extracellular vesicles (EVs), as paracrine components of stem cells, are natural nanoscale particles that transport a variety of biological molecules and facilitate cell-to-cell communication which have been also widely used for targeted drug delivery. These nanocarriers exhibit inherent advantages, such as strong cell or tissue targeting and low immunogenicity, which synthetic nanocarriers lack. However, despite the tremendous therapeutic potential of stem cells and EVs, their further clinical application is still limited by low yield and a lack of standardized isolation and purification protocols. In recent years, inspired by the concept of biomimetics, a new approach to biomimetic nanocarriers for drug delivery has been developed through combining nanotechnology and bioengineering. This article reviews the application of biomimetic nanocarriers derived from stem cells and their EVs in targeted drug delivery and discusses their advantages and challenges in order to stimulate future research