This kit provides a fast, reliable and convenient method to purify and concentrate high quality, high purity and inhibitor-free cell-free circulating RNA, including exosomal RNA as well as viral RNA from fresh, preserved or frozen urine samples from volumes ranging from 250 µL to 2 mL. All components for the purification are provided in one convenient and fast kit for the easy processing of small input volumes of bodily fluids. The purified urine RNA is fully compatible with all downstream applications including PCR, qPCR, methylation-sensitive reverse transcription qPCR, reverse transcription PCR, Northern blotting, RNase protection and primer extension, expression array assays, and NGS.
Recent evidence indicates that cell-free circulating RNA (cf-RNA) including exosomal RNA in urine contains valuable information for the discovery of biomarkers that can help for the early detection of certain cancer types and for monitoring the disease status as well as for the detection of any infectious pathogens. Exosomes can be found in saliva, blood, urine, amniotic fluid and malignant ascitic fluids, among other biological fluids. Evidence has been accumulating recently that these vesicles act as cellular messengers, conveying information to distant cells and tissues within the body. These exosomes may play a functional role in mediating adaptive immune responses to infectious agents and tumours, tissue repair, neural communication and transfer of pathogenic proteins. For this reason exosomal RNAs may serve as biomarkers for various diseases including cancer. The advantage for using urine as a source for cancer biomarkers is that it can be acquired in large quantities without using invasive procedures. In addition, repeated sampling from the same individual is applicable, which facilitates longitudinal studies. There are many advantages favouring the use of urinary nucleic acid for cancer biomarker discovery over blood, tissue samples or other bodily fluids, including: (1) urine is non-infectious for HIV and less infectious for many other pathogens; (2) the profile of urinary nucleic acid is similar to that in plasma or serum but with a lower concentration; (3) Nucleic acid purification from urine is technically much easier because of its low protein concentration (1000-fold lower than blood).