Fig. 7: RFC4 is amplified in NSCLC and correlates with NSCLC progression.

a GSEA analysis of the TCGA lung cancer datasets by Kolmogorov–Smirnov test shows correlation between RFC4 and tumor metastasis- and stemness-associated signatures. b Images of IHC staining for RFC4 and NICD1 in the same set of consecutive tissue slices of primary tumors from 219 NSCLC patients with or without LN metastasis, and the percentages of specimens expressing low or high RFC4 from these NSCLC patients. Two representative cases are shown. Scale bar: 100 μm. c Kaplan–Meier analysis of the LN metastasis-free survival of our cohort of 219 NSCLC patients by log-rank test, who were divided into low- or high RFC4 and low- or high-NICD1 expression subgroups. The medians of RFC4 and NICD1 expression were used as the cut-off value. d The percentages of RFC4 genetic alterations in LUAD and LUSC patients from the TCGA lung cancer datasets. e The RFC4 DNA quantities in 10 pairs of NSCLC tissues and adjacent non-cancerous lung tissues. f The percentages of RFC4 genetic alterations with or without metastasis from the TCGA lung cancer datasets, which was analyzed by cross-tabulation with two-tailed Chi-square test. g Images of FISH staining for RFC4 genomic amplification status in primary tumors from NSCLC patients with or without LN metastasis. Two representative cases are shown. Scale bar: 10 μm. h Kaplan–Meier analysis of the correlation between RFC4 DNA levels or amplification status and metastasis-free survival of NSCLC patients from our own cohort by Log-rank test. RFC4 DNA level was used as the cut-off value. i Kaplan–Meier analysis of the correlation between RFC4 amplification status and overall survival of NSCLC patients from TCGA lung cancer datasets by log-rank test. Data in panel b, e are presented as mean ± SD derived from three independent experiments. Two-way ANOVA multiple comparison analysis was used for statistical analysis. Source data are provided as a Source Data file.