Background:
Variations in mitochondrial DNA copy number (mtDNA-CN) of
peripheral blood leukocytes (PBLs), as a potential biomarker for gastric
cancer (GC) screening has currently been subject to controversy.
Herein, we have assessed its efficiency in GC screening, in parallel and
in combination with serum pepsinogen (sPG) I/II ratio, as an
established indicator of gastric atrophy.
Methods:
The study population included GC (n = 53) and non-GC (n = 207)
dyspeptic patients. The non-GC group was histologically categorized into
CG (n = 104) and NM (n = 103) subgroups. The MtDNA-CN of PBLs was
measured by quantitative real-time PCR. The sPG I and II levels and
anti-H. pylori serum IgG were measured by ELISA.
Results:
The mtDNA-CN was found significantly higher in GC vs. non-GC (OR =
3.0; 95% CI = 1.4, 6.4) subjects. Conversely, GC patients had
significantly lower sPG I/II ratio than the non-GC (OR = 3.2; CI = 1.4,
7.2) subjects. The combination of these two biomarkers yielded a
dramatic amplification of the odds of GC risk in double-positive (high
mtDNA-CN-low sPGI/II) subjects, in reference to double-negatives (low
mtDNA-CN-high sPGI/II), when assessed against non-GC (OR = 27.1; CI =
5.0, 147.3), CG (OR = 13.1; CI = 2.4, 72.6), or NM (OR = 49.5; CI = 7.9,
311.6) groups.
Conclusion:
The combination of these two biomarkers, namely mtDNA-CN in PBLs
and serum PG I/II ratio, drastically enhanced the efficiency of GC risk
assessment, which calls for further validations.