Tumor cell-derived exosomal microRNA-146a promotes non-small cell lung cancer cell invasion and proliferation by inhibiting M1 macrophage polarization

Zhi Yan; Jian-Xun Wen; Xi-Shan Cao; Wen Zhao; Yu-Ling Han; Xu-Hui Wen; Li Yan; Man Zhang; Ya-Fei Wang; Ling Hai; Ying-Jun Wang; Wen-Qi Zheng; Zhi-De Hu

doi:10.21037/atm-22-5565

Tumor cell-derived exosomal microRNA-146a promotes non-small cell lung cancer cell invasion and proliferation by inhibiting M1 macrophage polarization

Ann Transl Med. 2022 Dec;10(24):1307. doi: 10.21037/atm-22-5565.

Authors

Zhi Yan^#^{1

2}, Jian-Xun Wen^#³, Xi-Shan Cao¹, Wen Zhao¹, Yu-Ling Han^{1

2}, Xu-Hui Wen^{1

2}, Li Yan⁴, Man Zhang⁵, Ya-Fei Wang¹, Ling Hai^{6

7}, Ying-Jun Wang¹, Wen-Qi Zheng^{1

2}, Zhi-De Hu¹

Affiliations

¹ Department of Laboratory Medicine, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China.
² Department of Parasitology, the Basic Medical Sciences College of Inner Mongolia Medical University, Hohhot, China.
³ Department of Medical Experiment Center, the Basic Medical Sciences College of Inner Mongolia Medical University, Hohhot, China.
⁴ Department of Respiratory and Critical Care Medicine, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China.
⁵ Department of Thoracic Surgery, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China.
⁶ Department of Pathology, the College of Basic Medical, Inner Mongolia Medical University, Hohhot, China.
⁷ Department of Pathology, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, China.

^# Contributed equally.

Abstract

Background: Tumor-associated macrophages (TAMs) affects the outcomes of non-small cell lung cancer (NSCLC). NSCLC cells released exosomes to suppress the antitumor activity of TAMs. MiR-146a is a critical regulator in TAM polarization. We hypothesized that NSCLC cells released exosomal miR-146a to regulate TAM polarization and thus affected its antitumor activity.

Methods: We used H1299 cells-derived exosomes to stimulate THP-1 cells that was pretreated with phorbol 12-myristate 13-acetate (M0 macrophage). Flow cytometry and reverse transcription-quantitative polymerase chain reaction (PCR) were used to determine the polarization of macrophages. The conditioned medium of exosome-treated M0 cells was used to culture H1299 cells, and the Cell Counting Kit-8, Ki67, transwell and scratch wound assays were used to determine the biological behavior of H1299 cells. To investigate whether exosomal miR-146a regulates TAM macrophages through targeting tumor necrosis factor receptor-associated factor 6 (TRAF-6) and interleukin-1 receptor-associated kinase 1 (IRAK-1), we used small interfering RNA to knockdown the expressions of them.

Results: Upregulation of miR-146a inhibited M1 polarization and thus impaired the antitumor activity of TAMs. Exosomes released by H1299 cells can be taken by M0 macrophage, and they upregulated the expression of miR-146a in M0 macrophage. The exosome suppresses M1 polarization by exosomal miR-146a. TRAF-6 and IRAK-1 mediated the inhibitive effects of exosomal miR-146a on M1 polarization.

Conclusions: NSCLC cells released exosomal miR-146a to inhibit the expressions of TRAF-6 and IRAK-1 in TAMs, resulting in the impaired antitumor activity of TAMs. NSCLC cell-derived exosomal miR-146a represents a novel therapeutic target for NSCLC treatment.

Keywords: Non-small cell lung cancer (NSCLC); exosome; macrophage; miR-146a.