Significant Upregulation of HERV-K (HML-2) Transcription Levels in Human Lung Cancer and Cancer Cells

Caiqin Yang; Xin Guo; Jianjie Li; Jingwan Han; Lei Jia; Hong-Ling Wen; Chengxi Sun; Xiaolin Wang; Bohan Zhang; Jingyun Li; Yujia Chi; Tongtong An; Yuyan Wang; Ziping Wang; Hanping Li; Lin Li

doi:10.3389/fmicb.2022.850444

Significant Upregulation of HERV-K (HML-2) Transcription Levels in Human Lung Cancer and Cancer Cells

Front Microbiol. 2022 Mar 10:13:850444. doi: 10.3389/fmicb.2022.850444. eCollection 2022.

Authors

Caiqin Yang¹, Xin Guo², Jianjie Li³, Jingwan Han¹, Lei Jia¹, Hong-Ling Wen⁴, Chengxi Sun⁵, Xiaolin Wang¹, Bohan Zhang¹, Jingyun Li¹, Yujia Chi³, Tongtong An³, Yuyan Wang³, Ziping Wang³, Hanping Li¹, Lin Li¹

Affiliations

¹ Department of Virology, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, AMMS, Beijing, China.
² Department of Nutrition and Food Hygiene, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China.
³ Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Thoracic Medical Oncology, Peking University Cancer Hospital & Institute, Beijing, China.
⁴ Key Laboratory for the Prevention and Control of Infectious Diseases, Department of Microbiological Laboratory Technology, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China.
⁵ Department of Clinical Laboratory, Cheeloo College of Medicine, Shandong University, Jinan, China.

Abstract

Lung cancer is the second most common cancer worldwide and the leading cause of cancer death in the world. Therefore, there is an urgent need to develop new and effective biomarkers for diagnosis and treatment. Under this circumstance, human endogenous retroviruses (HERVs) were recently introduced as novel biomarkers for cancer diagnosis. This study focused on the correlation between lung cancer and HERV-K (HML-2) transcription levels. At the cellular level, different types of lung cancer cells and human normal lung epithelial cells were used to analyze the transcription levels of the HERV-K (HML-2) gag, pol, and env genes by RT-qPCR. At the level of lung cancer patients, blood samples with background information from 734 lung cancer patients and 96 healthy persons were collected to analyze the transcription levels of HERV-K (HML-2) gag, pol, and env genes. The results showed that the transcriptional levels of the HERV-K (HML-2) gag, pol, and env genes in lung cancer cells and lung cancer patient blood samples were significantly higher than those in the healthy controls, which was also verified by RNAScope ISH technology. In addition, we also found that there was a correlation between the abnormal transcription levels of HERV-K (HML-2) genes in lung cancer patients and the clinicopathological parameters of lung cancer. We also identified the distribution locations of the gag, pol, and env primer sequences on each chromosome and analyzed the function of these loci. In conclusion, HERV-K (HML-2) genes may be a potential biomarker for the diagnosis of lung cancer.

Keywords: HERV-K; RT–qPCR; biomarker; cell culture; diagnosis; in situ hybridization; lung cancer.