Metastatic disease is a main cause of mortality in prostate cancer and remains to be uncurable despite emerging new treatment agents. Development of novel treatment agents are confined within the boundaries of our knowledge of bone metastatic prostate cancer. Exploration into the underlying mechanism of metastatic tumorigenesis and treatment resistance will further expose novel targets for novel treatment agents. Up to date, many of these researches have been conducted with animal models which have served as classical tools that play a pivotal role in understanding the fundamental nature of cancer. The ability to reproduce the natural course of prostate cancer would be of profound value. However, currently available models cannot reproduce the entire process of tumorigenesis to bone metastasis and are limited to reproducing small portions of the entire process. Therefore, knowledge of available models and understanding the strengths and weaknesses for each model is key to achieve research objectives. In this article, we take an overview of cell line injection animal models and patient-derived xenograft models that have been applied to the research of human prostate cancer bone metastasis.

Bladder cancer is one of most common malignant urinary tract tumor types, and transurethral resection of nonmuscle invasive bladder cancer followed by intravesical instillation of immunochemotherapy is the standard treatment approach to minimize recurrence and delay progression of bladder cancer. In general, conventional intravesical immunochemotherapy lacks selectivity for tumor tissues and the effect of drug is reduced with the excretion of urine leading to frequent administration and bladder irritation symptoms. Recently, nanomedicines which adhere to the bladder tumors for a long time, and continuously and efficiently release drug to bladder cancers may overcome all the above problems. Moreover, the advances in nanomedicine based targeted therapy have led to significant improvements in drug efficacy and precision of targeted drug delivery. This review shows the available nano-systems of targeted drug delivery to bladder cancer tissues.