MicroRNA Profile Predicts Tumor Spread Through Air Spaces in Resected Lung Adenocarcinomas: A Pilot Study

Spread through air spaces (STAS), a mode of lung cancer progression, is recognized as a poor prognostic factor, although its pathogenesis remains unclear. This study aimed to identify microRNAs (miRNAs) associated with STAS.

Differentially expressed miRNAs were identified using miRNA array analysis of primary lung cancer tumor tissues and tissues suspected of STAS obtained from patients who underwent surgery for lung adenocarcinoma. We collected 20 samples (10 from the main tumor tissue; 10 from STAS lesions) from 10 patients.

With two samples exhibiting an RNA integrity number > 7, we performed miRNA analysis of the main tumor tissues and STAS lesions, identifying miRNAs differentially expressed in both cases. In both cases, miR-3136-5p was upregulated, and miR-3934-5p and miR-4793-3p were downregulated. We identified miRNAs with dysregulated expression in STAS tissues compared with those in tumor tissues.

We identified three miRNAs involved in STAS of lung cancer, and these miRNAs may be potential diagnostic and prognostic targets for STAS treatment. As research and development of small RNA-targeted therapeutics targeting cancer, inflammatory diseases, and cardiovascular diseases are progressing, the analysis of miRNA expression levels in STAS of lung cancer may lead to the development of diagnostic markers and potential treatment strategies for lung cancer with STAS.

Registry: Kagawa University.

2021-031. Date of registration: May 28, 2021.