Prevalence of CTLA-4 in patients with lung cancer

Abstract

Background: Immune-based therapies have shown promise in the treatment of patients with lung cancer. In order to perform immunotherapy, the protein should be identified in the cancer tissue. Currently, in our country, there is no research studies that have detected CTLA-4 proteins in lung cancer tissues. Aim: to determine the expression of cytotoxic T lymphocyte-associated protein 4 (CTLA-4) in patients with NSCLC and compare them with those patients’ clinical characteristics. Materials and Methods: Immunohistochemical analysis of CTLA-4 expression was performed in 30 samples from patients with NSCLC. CTLA-4 protein expression in cancer cells was divided into 4 groups according to the number of stained cells, <1%, ≥1%, ≥25%, and ≥50%, and the differences between the groups were analyzed using one-way ANOVA analysis. Results: CTLA-4 positive expression was found in 26 out of 30 (83.3%) specimens and a CTLA-4 score of the tumor greater than 7.3 was observed in 10 of 30 patients, and these patients were considered to have high expression. CTLA-4 with high expression was found in specimens 35% in patients older than 63, 30.7% in smokers, 35.2% in patients with disease stage I-II, and 30.7% in patients with disease stage III-IV, respectively. The association study showed that CTLA4 expression was not significantly associated with the clinical characteristics of the patients, such as gender, age, smoking status, clinical stages, and metastasis. Conclusion: Cytotoxic T lymphocyte-associated protein 4 (CTLA-4) protein expression was in non-small cell lung cancer and suggested that possible to introduce immunotherapy.