Extracellular Nucleic Acids in Urine: Sources, Structure, Diagnostic Potential

Area of Science:

• Biochemistry
• Molecular Biology
• Urology

Background:

• Cell-free nucleic acids (cfNA) are present in urine from various sources, including cell necrosis, apoptosis, and active secretion by urinary tract cells.
• Circulating nucleic acids (cir-NA) from blood can also enter primary urine.
• Urinary cfNA, though fragmented, holds potential for detecting specific marker sequences.

Purpose of the Study:

• To review current data on the origins of urinary cfNA.
• To discuss the structural characteristics and diagnostic potential of urinary cfNA.
• To summarize factors influencing the stability of cfNA in urine.

Main Methods:

• Literature review of existing studies on urinary cfNA.
• Analysis of data on cfNA sources, structure, and stability.
• Evaluation of the diagnostic utility of cfNA and microRNAs in urine.

Main Results:

• Urinary cfNA originate from both healthy and tumor cells, as well as circulating sources.
• Fragmented urinary DNA and RNA can serve as detectable marker sequences.
• MicroRNAs are also identified as significant diagnostic probes in urine.
• cfNA stability is influenced by their supramolecular packaging and the urine's nuclease activity.

Conclusions:

• Urinary cfNA represent a promising, non-invasive source for molecular diagnostics.
• Understanding the factors affecting cfNA stability is crucial for optimizing their diagnostic application.
• Further research into cfNA structure and stability can enhance their utility in detecting urinary tract conditions.