AUTHOR=Jiang Lai , Ren Xing , Yang Jinyan , Chen Haiqing , Zhang Shengke , Zhou Xuancheng , Huang Jinbang , Jiang Chenglu , Gu Yuheng , Tang Jingyi , Yang Guanhu , Chi Hao , Qin Jianhua TITLE=Mitophagy and clear cell renal cell carcinoma: insights from single-cell and spatial transcriptomics analysis JOURNAL=Frontiers in Immunology VOLUME=15 YEAR=2024 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2024.1400431 DOI=10.3389/fimmu.2024.1400431 ISSN=1664-3224 ABSTRACT=Background

Clear Cell Renal Cell Carcinoma (ccRCC) is the most common type of kidney cancer, characterized by high heterogeneity and complexity. Recent studies have identified mitochondrial defects and autophagy as key players in the development of ccRCC. This study aims to delve into the changes in mitophagic activity within ccRCC and its impact on the tumor microenvironment, revealing its role in tumor cell metabolism, development, and survival strategies.

Methods

Comprehensive analysis of ccRCC tumor tissues using single cell sequencing and spatial transcriptomics to reveal the role of mitophagy in ccRCC. Mitophagy was determined to be altered among renal clear cells by gene set scoring. Key mitophagy cell populations and key prognostic genes were identified using NMF analysis and survival analysis approaches. The role of UBB in ccRCC was also demonstrated by in vitro experiments.

Results

Compared to normal kidney tissue, various cell types within ccRCC tumor tissues exhibited significantly increased levels of mitophagy, especially renal clear cells. Key genes associated with increased mitophagy levels, such as UBC, UBA52, TOMM7, UBB, MAP1LC3B, and CSNK2B, were identified, with their high expression closely linked to poor patient prognosis. Particularly, the ubiquitination process involving the UBB gene was found to be crucial for mitophagy and its quality control.

Conclusion

This study highlights the central role of mitophagy and its regulatory factors in the development of ccRCC, revealing the significance of the UBB gene and its associated ubiquitination process in disease progression.