Аңдатпа
Relevance. Circulating microRNAs are promising minimally invasive biomarkers for the diagnosis of non-small cell lung cancer. However, their biological origin remains insufficiently understood. If the primary tumor represents their principal source, surgical tumor resection would be expected to reduce their plasma levels. Objective. To determine whether plasma levels of previously identified diagnostic miRNAs decrease following surgical tumor resection in patients with non-small cell lung cancer. Materials and methods. The study included 18 patients with histologically confirmed non-small cell lung cancer and 41 healthy controls who participated in our previous study. Paired patient plasma samples were collected before surgery and 14–119 days after surgery, prior to adjuvant therapy. The experimental workflow included magnetic bead-based RNA isolation, reverse transcription, TaqMan-based real-time PCR, and normalization to the exogenous spike-in control ath-miR-159a. Statistical analyses included correction for multiple comparisons. Results. Seven miRNAs (miR-130b-3p, miR-1-3p, miR-423-5p, miR-200a-3p, miR-154-5p, miR-376a-3p, and miR-18b-5p) were significantly elevated in preoperative plasma compared with healthy controls. Five remained significantly elevated after surgery. No statistically significant postoperative decrease in NSCLC-associated candidate miRNAs was detected after correction for multiple comparisons. Three miRNAs (miR-495-3p, miR-191-5p, and miR-543) showed postoperative decreases at nominal p < 0.05, but these differences did not remain significant after correction. Their preoperative levels did not differ significantly from those of healthy controls. No statistically significant correlation was detected between postoperative miRNA levels and the time from surgery to postoperative blood sampling in this sample. Conclusions. No statistically significant postoperative decrease in non-small cell lung cancer-associated candidate miRNAs was detected after correction for multiple comparisons. These findings do not establish their cellular origin or validate their utility for postoperative disease monitoring. Larger prospective studies are required.