The expression levels of (A)
CCNA1, (B)
SNCA, and (C)
ZNF549 in normal lung tissues (NLT) obtained from cancer-free
never smokers (NLT-NS) and smokers (NLT-S), tumor-normal pairs from lung cancer
patients, and NSCLC cell lines were quantified using gene-specific expression
assays. The distant normal lung tissue (DNLT) and tumor pairs were all from
smoker LUAD cases with or without COPD. Thus, they were separated into the
following 4-groups: DNLT without COPD (DNLT-COPD) or with COPD (DNLT+COPD) and
tumors without COPD (Tumor-COPD) or with COPD (Tumor+COPD). Expression is
measured relative to the level in NLT-NS and the significant changes from NLT-NS
(✭), NLT-S (◆), DNLT-COPD (Δ), DNLT+COPD (☐), or
Tumor-COPD (■) are shown. D) RNA-seq data for the expression
of CCNA1, SNCA, and ZNF549 in
normal lung tissues and LUAD samples from TCGA database was used to
independently validate the repression of these genes.