Abstract 6797: CCR5/CCL4 axis in lung cancer clinicopathological significance and its therapeutic application

Abstract Lung cancer (LC) is the most prevalent type of cancer globally and the leading cause of cancer-related deaths. Based on the histology and type of treatments, LC is divided into small-cells and non-small cell lung cancer (NSCLC) carcinomas, which are more aggressive and less responsive to chemotherapy. Since LC is known to be a highly heterogeneous cell population, treatment is challenging. It has been observed that chemokine receptor-ligand interaction is essential for cancer cells homing to distant sites. Most malignancies, including LC, have established disease status indicators concerning elevated levels of CCL4, a structurally unique chemokine, and its receptor (CCR5). Therefore, treatment strategies that inhibit the LC cell's tumor environment may improve patients' quality of life. However, the CCR5/CCL4 interface in LC invasion and metastasis is poorly understood. In this study, we examined the expression and function of the CCR5/CCL4 axis in the development and invasiveness of LC patient's clinical tissues and cell lines. We conducted immunohistochemistry (IHC) dual staining of CCR5/CCL4 antibodies in LC tissues. Our findings demonstrated significantly (p 0. 001) higher expression of CCR5 and CCL4 in advanced-stage malignant tissues than in normal tissues. The in-vitro analysis of the human LC cell lines NCI-H1437, NCI-H1573, and NCI-H1975 revealed CCL4 activation expressing higher CCR5, determined by immunofluorescence, western blots, flow cytometry, 3D-invasion assay, and RT-qPCR methods. Further, a calcium mobilization assay confirmed the direct interaction between CCR5 and CCL4. However, treating with Maraviroc, a small molecule inhibitor of CCR5, to LC cells blocks their ability to proliferate, demonstrating the crucial role that CCR5-CCL4 chemotaxis plays in LC metastasis. Our findings show both the biological and clinical significance of CCR5 and CCL4 expression, which may serve as potential indicators for metastatic LC. Therefore, inhibiting the CCR5/CCL4 interaction may offer a more effective therapeutic approach for managing the progression of LC. Citation Format: Santosh K. Singh, Rajesh Singh. CCR5/CCL4 axis in lung cancer clinicopathological significance and its therapeutic application abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 6797.