Establishment of a prognostic model toward lung squamous cell carcinoma based on mG-related genes in the cancer genome atlas.

Lung squamous cell carcinoma (LUSC) is a non-small cell lung cancer with a poor prognosis owing to late diagnosis. New molecular markers are urgently needed to improve the diagnosis and prognosis of LUSC. 7-Methylguanosine (mG) modifications, a tRNA modification, are common in eubacteria, eukaryotes, and a few archaea. These modifications promote the turnover and stability of some mRNAs to prevent mRNA decay, improve translation efficiency, and reduce ribosomal pausing but are associated with poor survival in human cancer cells. However, expression of mG-related genes in LUSC and their association with prognosis remain unclear. In the present study, we identified nine differentially expressed genes related to prognosis by comparing the expression profiles of tumor tissues (502 LUSC reports) with normal tissues (49 adjacent nontumor lung tissue reports). The genes included six upregulated genes (, , , , , and ) and three downregulated genes (, , and ). Based on these nine genes, patients with LUSC were classified into low- and high-risk groups to analyze the trends in prognosis. We found that the nine mG-related genes play important roles in immune regulation, hormone regulation, and drug sensitivity through pathways including antigen processing and presentation, adherent plaques, extracellular matrix receptor interactions, drug metabolism of cytochrome -450, and metabolism of cytochrome -450 to xenobiotics; the functions of these genes are likely accomplished in part by mA modifications. The effect of mG-related genes on the diagnosis and prognosis of LUSC was further indicated by population analysis. Based on the differential expression of 7-methylguanosine (mG) modification-associated genes between normal and lung squamous cell carcinoma (LUSC) tissues, and considering the performance of our mG-related gene risk profiles as independent risk factors in predicting overall survival, we conclude that mG modification is closely linked to the development of LUSC. In addition, this study offers a new genetic marker for predicting the prognosis of patients with LUSC and presents a crucial theoretical foundation for future investigations on the relationship between mG modification-related genes, immunity, and drug sensitivity in LUSC.