Association between the miRNA Signatures in Plasma and Bronchoalveolar Fluid in Respiratory Pathologies

Abstract

Abstract. The identification of new less invasive biomarkers is necessary to improve the detection and prognostic outcome of respiratory pathological processes. The measurement of miRNA expression through less invasive techniques such as plasma and serum have been suggested to analysis of several lung malignancies including lung cancer. These studies are assuming a common deregulated miRNA expression both in blood and lung tissue. The present study aimed to obtain miRNA representative signatures both in plasma and bronchoalveolar cell fraction that could serve as biomarker in respiratory diseases. Ten patients were evaluated to assess the expression levels of 381 miRNAs. We found that around 50% miRNAs were no detected in both plasma and bronchoalveolar cell fraction and only 20% of miRNAs showed similar expression in both samples. These results show a lack of association of miRNA signatures between plasma and bronchoalveolar cytology in the same patient. The profiles are not comparable; however, there is a similarity in the relative expression in a very small subset of miRNAs (miR-17, miR-19b, miR-195 and miR-20b) between both biological samples in all patients. This finding supports that the miRNAs profiles obtained from different biological samples have to be carefully validated to link with respiratory diseases.

MicroRNA clusters: dysregulation in lung adenocarcinoma and COPD

“…Moreover, the biological specimens employed for profiling have to be taken into account as it may significantly contribute to the widely variable results observed. In this regard it should be pointed out, as we have previously reported, that there is a very poor correlation between expression patterns observed in circulating plasma miRNAs compared to those assessed in BAL cell fraction-derived miRNAs from the same patient [11]. In our opinion, however, BAL fluid is likely more informative of the actual lung pathological conditions under study.…”

“…Total RNA, containing small RNA, was extracted from the cell fraction of BAL samples and quantified as previously described [11]. Expression of 381 human miRNAs was quantified in the training cohort using the TaqMan Human MicroRNA A Array v2.0 (Applied Biosystems (Life Technologies S.A.), Madrid, Spain) according to the manufacturer's instructions.…”

Expression profile of plasma microRNAs in nonsyndromic cleft lip and their clinical significance as biomarkers

“…Because of plasma miRNAs' high stability under handling and storage conditions [17], they have the potential to become novel diagnostic biomarkers for cancer [18,19], respiratory diseases [20], and other conditions. Nonsyndromic cleft lip is one type of oral clefting without cleft palate or other developmental syndromes.…”

Extracellular Nucleic Acids and Cancer

“…When cfmiRNAs from serum and cerebrospinal fluid from patients with neurological diseases were profiled by NGS, there were (as one could expect) substantial differences found [261]. A similar observation was made when miRNA signatures from plasma and bronchial lavage fluid from the same patients were compared [262]. For the detection of genetic alterations associated with tumors of the gastro-intestinal tract gastric juice, pancreatic juice and/or feces/lavage fluid obtained during colonoscopy might be better suited than either plasma or serum.…”