Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 24 5 2025 09 16 653 663 EN Ali Rahimi Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Hossein Khorramdelazad Department of Immunology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran Ali Darehkordi Department of Chemistry, Faculty of Science, Vali-e-Asr University of Rafsanjan, Rafsanjan, Iran Gholamhossein Hassanshahi Department of Immunology, School of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran Majid Khoshmirsafa Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Milad Karimi Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Reza Falak Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Elaheh Safari Department of Immunology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran AND Breast Health and Cancer Research Center, Iran University of Medical Sciences, Tehran, Iran AND Immunology Research Center, Iran University of Medical Sciences, Tehran, Iran 2024 11 09 2025 01 11 The impacts of the CXC motif chemokine 12 (CXCL12)/ C-X-C chemokine receptor type 4 (CXCR4) axis on the infiltration of anti-tumor and pro-tumor immune cells in the tumor microenvironment (TME) of breast cancer (BCa) have been noted in previous studies. Accordingly, regulating the downstream signals of this axis can effectively increase CD8+ cytotoxic T cells and decrease the frequency of immunosuppressive cells in the TME. This study investigated the anti-tumor effects of N, N''-thiocarbonylbis (N'-(3,4-dimethylphenyl)-2,2,2 trifluoroacetimidamide) (A1), a novel fluorinated CXCR4 inhibitor on a BCa cell line. In this study, the impacts of A1 on cell viability, proliferation, apoptosis, and cell cycle were examined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry assays. Moreover, the effect of A1 on the number of CXCR4+ 4T1 cells was measured by flow cytometry. A1 treatment exhibited cytotoxic effects on 4T1 cells, promoting cell apoptosis and G2/M cell cycle arrest. In addition, A1-treated cells showed a reduced cell proliferation than CXCL12 treated cells. Furthermore, treatment with A1 alongside CXCL12 significantly decreased the number of CXCR4+ cells compared to the control group treated with only CXCL12 as a proliferator factor. These results indicate that A1 exerts potential anti-tumor effects and may serve as a possible therapeutic agent for BCa treatment; however, further studies are required. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/4242 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/4242/2198