Background: MicroRNAs (miRs) are a group of small non-coding and single-stranded RNAs of 18
to 25 nucleotides. The study of microRNAs is one of the new ways to detect cancer. In this study, the serum
expression of miR-223 in patients with GC was measured and compared with the control group.
Methods: This case-control study was conducted on 39 patients with GC and 39 control subjects who visited the
Reza Radiotherapy and Oncology Center, Mashhad, Iran, due to gastrointestinal complaints. The demographic
information was collected, and the serum levels of miR-223 were measured using the real-time PCR technique
in all study subjects. The association between the GC of miR-223 and tumor staging and cancer progression was
Results: The miR-223 expression in GC patients was 3.10-fold higher than that of the control group
(p<0.0001). The miR-223 expression was significantly higher in the GC stages and grades compared to the
control group (p<0.0001 each). However, there was no significant effect for age, smoking, and gender on miR-
223 expression in GC and controls. At the optimal cutoff value of 0.7436, the maximal sensitivity of 89.74%
and specificity of 84.62% were achieved for miR-223 (p<0.001). The sensitivity and specificity for miR-223 for
differentiating low grades from high grade were 92.31% and 73.08% (p=0.0003), and for differentiating low
stages from the high stage was 81.82% and 39.29% respectively (p=0.696).
Conclusion: This study revealed that miR-223 could be considered as a non-invasive diagnostic marker in the
early diagnosis of GC.