Objective To investigate the expression of intercellular junction proteins claudin18.2(Claudin18.2) and E-Cadherin in colon cancer (CC) tissues and observe their correlations with clinicopathological features and prognosis of CC patients.

Methods A total of 106 patients diagnosed with CC by pathology and treated at Wuxi Xinrui Hospital from February 2021 to February 2024 were selected as study subjects. All patients underwent surgical resection, and cancer tissue and adjacent tissue samples, along with clinicopathological data were collected. Immunohistochemistry was used to detect the protein expression of Claudin18.2 and E-Cadherin in the tissues. After a 1-year follow-up, patients were divided into survival group (n=69) and death group (n=37) based on their prognosis. Cox regression analysis was performed to identify factors affecting the survival of CC patients. Kaplan-Meier curves were used to observe the relationships of the expression of Claudin18.2 and E-Cadherin with the survival rate of CC patients.

Results The positive expression rate of Claudin18.2 in cancer tissues was 48.11% (51/106), which was higher than 12.26% (13/106) in adjacent tissues. The positive expression rate of E-Cadherin in cancer tissues was 37.74% (40/106), which was lower than 66.98%(71/106) in adjacent tissues (P < 0.05). Among CC patients with positive Claudin18.2 expression, the proportions of patients in Dukes stage C 68.63% (35/51) and with lymph node metastasis 64.71% (33/51) were higher than that in patients with negative expression (P < 0.05). Among CC patients with positive E-Cadherin expression, the proportions of patients in Dukes stage A to B 67.50% (27/40) and without lymph node metastasis 72.50% (29/40) was higher than those in patients with negative expression (P < 0.05). Compared with the survival group, the death group had a higher proportion of patients in Dukes stage C, with lymph node metastasis, and with positive Claudin18.2 expression, and a lower proportion of patients with positive E-Cadherin expression, with statistically significant differences (P < 0.05). Kaplan-Meier survival analysis showed that the 1-year overall survival rate of patients with positive Claudin18.2 expression was 33.33% (17/51), which was lower than 94.55% (52/55) of patients with negative expression (Log Rank χ²=48.456, P < 0.001). The 1-year overall survival rate of patients with positive E-Cadherin expression was 90.00% (36/40), which was higher than 50.00% (33/66) of patients with negative expression (Log Rank χ²=18.304, P < 0.001). Dukes stage C, lymph node metastasis, and positive Claudin18.2 expression were all risk factors for poor prognosis in CC (P < 0.05), while positive E-Cadherin expression was a protective factor against poor prognosis in CC (P < 0.05).

Conclusion Positive Claudin18.2 expression and negative E-Cadherin expression are associated with poor prognosis in CC patients. They have an antagonistic effect and can be used as indicators for evaluating patient prognosis, providing certain value for assessing clinical outcomes and formulating diagnosis and treatment strategies.