Granulocytes as an effector mechanism of BCG therapy for bladder cancer

96DRA-urine: A high throughput sample preparation method for urinary proteome analysis

Mass spectrometry (MS)-based urinary proteomics is increasingly used for clinical research. A critical step in urinary proteomic analysis comprises the implementation of a reliable sample preparation method with high yields of peptides and proteins. In this study, we developed a urinary sample preparation method, DRA-Urine (Direct reduction/alkylation in urine), which urinary proteins were directly reduced/alkylated in urine, and then precipitated by acetone, washed and digestion on an ultrafilter unit. The qualitative and quantitative comparison of different urinary sample preparation methods (in-solution methods and ultrafilter-assisted methods) showed that DRA-Urine could achieve better results. Adapting DRA-Urine protocol to a 96-well format, namely 96DRA-Urine, shortened the time for buffer change and improved sample preparation throughput. The results showed that 96DRA-Urine displayed similar proteomic performance to DRA-Urine. Finally, the 96DRA-Urine method was used in a label-free, small pilot biomarker discovery analysis for differential urinary proteome analysis of bladder cancer urine. The results showed that urinary proteins could differentiate bladder cancer (BCa) patients from healthy controls and distinguish high-grade BCa from low-grade BCa with area under the curve (AUC) values of 0.972 and 0.847, respectively. Consequently, the 96DRA-Urine method might be a high-throughput method for preparing body fluid samples used in clinical research but needs to be further verified.

Mechanisms of BCG in the treatment of bladder cancer-current understanding and the prospect

Over 30 years' successful application of Bacillus Calmette Guerin (BCG) to the clinical treatment of bladder cancer has proved it one of the most promising immunotherapies for cancer. However, the applications and achievements have failed to uncover the mechanism of BCG works on bladder cancer fully. Clinically, the administration of BCG on patients results in no effect, or apparent resistance, and even severe adverse reactions, which are inexplicable. At present, the widely confirmed and accepted immunity mechanism of BCG fall in the processes of the absorption after the instillation of BCG, the internalization of BCG, cytokine release induced by a series of signal transduction pathways, and the effect stage of innate and acquired immune responses. Nonetheless, the limited ascertainments of the mechanism of BCG action cannot fully explain the clinical phenomenon caused by BCG. Therefore, the other mechanisms of BCG action have remained the research hotspot aiming to explore more targeted treatments or to initiate new therapeutic methods avoiding harm. By summarizing the recent research achievements of the mechanism of BCG works on bladder cancer, this review aims to provide clues for researchers to quest more valuable ideas.