Lung cancer (LC) is a prevalent
malignancy worldwide with increased morbidity and mortality. Mitochondrial
nicotinamide adenine dinucleotide-dependent deacetylase sirtuin-3 (
SIRT3) has been reported to be involved in
tumorigenesis. In this retrospective study, we measured the expression and diagnostic value of
SIRT3 in LC patients.Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to measure serum
SIRT3 mRNA level in 150 LC patients and 52 healthy volunteers.
SIRT3 protein level was detected using western blot for 84 pairs of LC and adjacent normal tissues. The association of
SIRT3 mRNA level with clinical parameters of LC patients was estimated via chi-square test. Receiver operating characteristic curve (ROC) was plotted to evaluate the diagnostic performance of serum
SIRT3 in LC patients.
SIRT3 mRNA and
protein levels were significantly decreased in LC tissues and serum samples, compared with corresponding controls (P < .05). Moreover, the expression of
SIRT3 mRNA was negatively associated with
tumor size (P = .002),
tumor node
metastasis stage (P < .001), and
metastasis (P < .001). ROC curve demonstrated that serum
SIRT3 could distinguish LC patients from healthy individuals, with an area under the curve of 0.918. The optimal cutoff value was 3.12, reaching a sensitivity of 86.4%, and a specificity of 94%.
SIRT3 expression is significantly down-regulated in LC serum and tissues.
SIRT3 may be employed as a promising
biomarker in the early diagnosis of LC.