Association between active pulmonary tuberculosis and circulating microRNAs: a preliminary study from Turkey

Area of Science:

• Biochemistry
• Molecular Biology
• Immunology

Background:

• Tuberculosis remains a significant global public health challenge requiring novel diagnostic biomarkers.
• MicroRNAs (miRNAs) play crucial roles in immune responses and disease progression, making them potential diagnostic indicators.
• The diagnostic value of specific miRNAs in active pulmonary tuberculosis (APT) within the Turkish population has not been previously explored.

Purpose of the Study:

• To investigate the potential diagnostic value of specific microRNAs in serum for active pulmonary tuberculosis (APT).
• To assess the expression levels of candidate microRNAs in the Turkish population with APT compared to healthy controls.
• To evaluate the utility of different reference genes for microRNA expression analysis in APT.

Main Methods:

• Quantitative polymerase chain reaction (qPCR) was employed to measure serum microRNA expression levels.
• Expression of selected microRNAs was compared between APT patients and healthy individuals.
• Normalization was performed using two different reference genes, U6 and miR-93, to assess their impact on results.

Main Results:

• Down-regulation of miR-144 was observed in APT patients irrespective of the normalization reference (U6 or miR-93).
• Significant decreases in miR-125b and miR-146a expression were noted when normalized with miR-93, but not with U6.
• Receiver operating characteristic analysis indicated that miR-144 is a potential biomarker for differentiating APT patients from controls.

Conclusions:

• miR-144 demonstrates potential as a diagnostic biomarker for active pulmonary tuberculosis.
• The choice of a single reference gene for microRNA expression analysis can be misleading.
• Combined use of U6 and miR-93 is recommended for reliable normalization of serum microRNA expression data in tuberculosis research.