Immune Effect of T Lymphocytes Infiltrated by Tumors on Non-Small-Cell Lung Cancer

Abstract

Lung cancer is increasing every year and it has high morbidity and mortality. Antitumor immunotherapy is a new method for the treatment of lung cancer. Currently, tumor immunotherapy mainly includes classical immunotherapy and immune-targeted therapy To explore the influence of tumor T-lymphocyte (T-cell) infiltration in non-small-cell lung cancer (NSCLC) patients, 100 NSCLC patients diagnosed and treated in Changde Second People’s hospital were recruited. Patients were followed up for 3 years. The subjects were divided into a survival group (group S) and a death group (group D). The patient’s pathological tissue sections were made, and the degree of T-cell infiltration was counted by H&E (Hematoxylin and eosin) staining. The infiltration degree was graded, and the positive rate of T-cell subsets was calculated by immunohistochemical staining. The 3-year positive rate was 48%, with 48 cases in group S and 52 cases in group D. The positive rate of H&E staining of group S was 100%, including 0 cases of grade 0, 5 cases of grade 1 (10.42%), 16 cases of grade 2 (33.33%), and 27 cases of grade 3 (56.25%). The positive rate of group D was 86.54%, including 4 cases of grade 0 (8.89%), 10 cases of grade 1 (22.22%), 25 cases of grade 2 (55.56%), and 6 cases of grade 3 (13.33%). The total number of T-cell infiltrates in group S was much higher than that in group D ( $P<0.05$ ). Immunohistochemical results showed that the mean positive rate of CD8+ T-cell infiltration was 72.1% in group S and 47.6% in group D, with a considerable difference ( $P<0.05$ ). No remarkable difference was found in CD4+ and CD25+ ( $P<0.05$ ). CD8+ + CD4+, CD8+/CD4+, CD25+/CD8+, CD25+/CD4+, and CD25+/(CD8+ + CD4+) positive rates were calculated, and the difference between group S and group D was substantial in CD8+ + CD4+ ( $P<0.05$ ). The results showed that T cells infiltrated by tumors had an immunosuppressive effect on tumor cells.