Abstract:

Objective To investigate the serum level of fatty acid binding protein 1 （FABP1） and its relationship with Helicobacter pylori （Hp） infection in patients with gastric cancer. Methods Forty gastric cancer patients （gastric cancer group） who were hospitalized in Affiliated Hospital of Qinghai University from August 2021 to August 2022 were selected as the research subjects，and 40 physical examination subjects during the same period were selected as the normal control group and 40 chronic atrophic gastritis patients were selected as the CAG group. The Hp infection were detected by ¹³C breath test，and the levels of serum FABP1 were detected by enzyme-linked immunosorbent assay. The Hp infection status，serum FABP1 levels，and the relationship between the two in the three groups of study subjects were analyzed. And the relationships between the level of serum FABP1 and the clinicopathological features of gastric cancer patients were analyzed. The diagnostic value of serum FABP1，CA19-9，CA72-4 and combined test of 3 indexes were evaluated by receiver operating characteristic （ROC） curve. Results The Hp infection rates in the control group，CAG group，and gastric cancer group were 32.50% （13/40），55.00% （22/40），and 60.00% （24/40），respectively，with a statistically significant difference （χ²=6.87，P=0.032）. Among them，the Hp infection rate in the control group was compared with that in the gastric cancer group，with a statistically significant difference （P<0.05），and there were no statistically significant differences between the CAG group and the control group，the gastric cancer group （both P>0.05）. The levels of serum FABP1 in the control group，CAG group，and gastric cancer group were [63.47 （37.53，71.59）] ng/ml，[65.26 （51.15，79.67）] ng/ml，and [72.84 （53.44，82.25）] ng/ml，respectively，with a statistically significant difference （H=6.62，P=0.037）. Among them，there was a statistically significant difference between the control group and the gastric cancer group （H=19.93，P=0.031），while there were no statistically significant differences between the CAG group and the control group，the gastric cancer group （H=1.50，P=0.133； H=1.09，P=0.277）. Among all study subjects，the levels of serum FABP1 in the Hp positive group （n=59） and Hp negative group （n=61） were [77.05 （68.90，83.54）] ng/ml and [47.80 （37.76，63.32）] ng/ml，respectively，with a statistically significant difference （Z=7.45，P<0.001）. In the control group，the levels of FABP1 in the serum of Hp positive and Hp negative persons were [77.34 （68.84，86.31）] ng/ml and [39.79 （36.83，63.75）] ng/ml，respectively，with a statistically significant difference （Z=4.46，P<0.001）. In the CAG group，the levels of FABP1 in the serum of Hp positive and Hp negative patients were [76.51 （65.30，80.97）] ng/ml and [49.34 （39.92，59.41）] ng/ml，respectively，with a statistically significant difference （Z=4.32，P<0.001）. In the gastric cancer group，the levels of FABP1 in the serum of Hp positive and Hp negative patients were [77.15 （72.62，84.13）] ng/ml and [50.57 （44.54，68.97）] ng/ml，respectively，with a statistically significant difference （Z=4.32，P<0.001）. There were significant correlations between the serum level of FABP1 and smoking （t=2.54，P=0.015），tumor diameter （t=2.23，P=0.035），and lymph node metastasis （t=3.22，P=0.003） in gastric cancer patients. And there were no significant correlations between FABP1 and gender （t=0.98，P=0.333），age （t=1.60，P=0.117），alcohol consumption （Z=0.10，P=0.925），tumor site （F=1.06，P=0.356），degree of differentiation （t=0.61，P=0.545），the depth of infiltration （t=1.41，P=0.166），distant metastasis （Z=1.96，P=0.050） and TNM staging （Z=0.66，P=0.508）. ROC curve analysis showed that the area under the curve （AUC） of serum FABP1 for gastric cancer diagnosis was 0.62，95%CI：0.51-0.72，the sensitivity and specificity were 57.50% and 68.70%，respectively； the AUC of CA19-9 for gastric cancer diagnosis was 0.89，95%CI：0.83-0.95，the sensitivity and specificity were 77.50%，86.30%，respectively； the AUC of CA72-4 for gastric cancer diagnosis was 0.88，95%CI：0.81-0.94，the sensitivity and specificity were 70.00%，93.70%，respectively； the AUC of combined test of 3 indexes for gastric cancer diagnosis was 0.91，95%CI：0.82-0.97，the sensitivity and specificity were 67.50% and 95.00%，respectively. Conclusion The Hp infection rate of gastric cancer patients is higher than that of the health examiners，the serum FABP1 level of gastric cancer patients is higher than that of the healthy health examiners，the serum FABP1 level of Hp positive persons is higher than that of Hp negative persons，and Hp infection and FABP1 level may have a common carcinogenic mechanism in the occurrence and development of gastric cancer.

Key words: Stomach neoplasms, Fatty acid-binding proteins, Helicobacter pylori