ABSTRACT
Objective Currently, there is a lack of clinical precise methods in the early diagnosis of gastric cancer. The article aimed to investigate the effect of serum amyloid A1 (SAA1) on the biological behavior of gastric cancer cells and its role in the early diagnosis of gastric cancer. Methods We collected 82 specimens of gastric cancer patients and 30 specimens of healthy controls. Cultured human gastric cancer SGC-7901 cells were randomly divided into SAA1-siRNA group, NC-siRNA group and blank control group. SAA1-siRNA, NC-siRNA and transfection reagent were transfected into the SGC-7901, and the expression of SAA1 protein in each group was detected by western blot 48 h later. Cell viability in each group was detected by CCK8 and cell invasion ability was measured by Transwell chamber. The ROC curve was used to analyze the efficacy of SAA1 in the diagnosis of gastric cancer. The expression of SAA1 was detected by ELISA, and the correlation between SAA1 and clinicopathological factors was analyzed. Results The SAA1 protein expression in SAA1-siRNA group [(1.12±0.12)μg] was significantly lower than those in NC-siRNA group[(1.97±0.13)μg] and blank control group[(2.09±0.28)μg] (P<0.05). The cell viability of CCK8 assay showed that the cell viability of SAA1-siRNA group(52.44±12.30) was significantly lower than those of NC-siRNA group(77.16±7.70) and blank control group (97.78±11.80). Transwell test results showed that the migration ability of SAA1-siRNA group(22.21±6.53) was significantly lower than those of NC-siRNA group(52.02±4.29) and blank control group(54.10±5.40)(P<0.05). The expression of SAA1 in patients with gastric cancer was (50.03 ± 20.89μg / mL) significantly higher than those of healthy controls (24.06 ± 10.72μg / mL), and the difference was statistically significant (P <0.05). ROC curve analysis showed that the AUC of SAA1 diagnosis of gastric cancer was 0.791 (95% CI: 0.701~0.880), the detection threshold was 31.97μg, and the diagnostic sensitivity and specificity were 0.659 and 0.833, respectively. There was no significant correlation between the expression of SAA1 and gender, age and tumor metastasis of gastric cancer (P> 0.05), while it was correlated with tumor maximum diameter and invasion degree, and increased with tumor invasion degree (P< 0.05). Conclusion The expression of SAA1 in gastric cancer patients increases significantly, which can be used as a new potential marker for the diagnosis of gastric cancer.