Expression of Wnt3, β - catenin and MMP - 7 in gastric cancer and precancerous lesions and their correlations with Helicobacter pylori infection.

Objectives: To compare the expression of the Wnt signaling-associated proteins (Wnt3, β-catenin, MMP-7) in gastric cancer and precancerous lesions with positive and negative Helicobacter pylori ( H.pylori , Hp ) infection, and to further explore the mechanisms underlying the Wnt signaling pathway involving in the formation of gastric cancer and its relationship with Hp infection.

Methods: The complete paraffin samples with pathologically confirmed diagnosis, who came from the First Hospital of Changsha from January 2018 to April 2020, were collected. All samples were randomly divided into a gastric cancer group ( n =57), a precancerous lesion group ( n =84), and a chronic superficial gastritis group ( n =25). Improved Giemsa staining was used to detect Hp infection, and according the results of Hp infection the above groups were divided into a Hp positive subgroup and a negative subgroup. The expressions of Wnt3, β-catenin and MMP-7 were examined with immunohistochemistry.

Results: The Wnt3, β-catenin, and MMP-7 were highly expressed in the gastric cancer group and the gastric precancerous lesion group. The Wnt3 and MMP-7 were highly expressed in cytoplasm, and β-catenin showed a tendency of cell membrane transferring to cytoplasm and nucleus, which was characterized by "nuclear translocation". The positive rates of the Wnt3, β-catenin, and MMP-7 expressions in the gastric cancer group were higher than those in the precancerous lesion group and the chronic superficial gastritis group (all P <0.05), which showed a gradually increasing trend with the deterioration of differentiation degree. In addition, the expressions of Wnt3, β-catenin, and MMP-7 in the Hp positive subgroup in the gastric cancer group and the precancerous lesion group were higher than those in the Hp negative subgroup (all P <0.05).

Conclusions: Aberrant activation of Wnt signaling pathway is involved in the occurrence and development of precancerous lesions and gastric cancer, and which is related with Hp infection. Meanwhile, the Wnt3, β-catenin and MMP-7 may be used as molecular markers for early diagnosis of gastric cancer and indicators to judge the degree of differentiation and malignancy of gastric cancer.