However, it is known that decreased mRNA expression of PcG genes is associated with poorer tumor differentiation and unfavorable prognosis for NSCLC patients [30]; this result complies with our finding that decreased BMI1 mRNA expression in peripheral whole blood of advanced patients is associated with a poor prognosis, potentially indicating the specific biological role of BMI1 in NSCLC progression. The gene discussed is BMI1; the disease is non-small cell lung carcinoma.