Inhibitory molecules expressed in T lymphocytes in patients with lung cancer before and after chemotherapy

Objective: The tumongenesis, progression, and metastasis of lung cancer are mostly governed by the immunosuppressive profile. This study aimed to explore the levels of various immunosuppressive inhibitory molecules in lung-cancer patients subjected to different chemotherapy cycles. Methods: Thirty-three patients with advanced lung cancer (ALC; stages III-IV) without receiving prior chemotherapy and 23 healthy subjects were enrolled in our study. Peripheral blood samples were collected from the patients before each chemotherapy cycle. The inhibitory markers expressed in T cells such as TIM3, PD-1, and CTLA4 were analyzed by flow cytometry. Results: The percentages of CD4⁺ T1M3⁺, CD8⁺ TIM3\ CD4⁺ PD-1⁺, CD8⁺ PD-1⁺, CD4⁺ CTLA-4⁺, and CD8⁺ CTLA-4⁺ T cells in the peripheral blood of the ALC patients were significantly higher compared to the controls. The percentage of CD4⁺ TIM3⁺, CD8⁺ TIM3⁺, CD4 ⁺ PD-1⁺, and CD8⁺ PD-1⁺ T lymphocytes in the peripheral blood of patients (n=19) who achieved PR or SD significantly decreased after five cycles of chemotherapy (PO.05). Similarly, the percentages of CD4⁺ CTLA-4⁺ and CD8 ⁺CTLA-4⁺ T cells in the patients also decreased after five cycles of treatment. Conclusion: The immune status of ALC patients was evidently suppressed. Effective chemotherapy successfully potentiated effective immune responses by downregulating inhibitory molecules in T cells.