The evaluation of the mechanism of interleukin-6 in immune inactivation of oral cancer

This study demonstrates the potential of sulindac to enhance resistance to tumor proliferation by both blocking tumor-induced immune suppression and stopping the growth of oral tumors. In contrast to adriamycin, sulindac significantly reduces the release of vascular endothelial growth factor (VEGF) and IL-6 from tumor cells by downregulating the NFκB and JNK signaling pathways. Additionally, it reduces the simultaneously induced production of VEGF and IL-6 during contacts between immune cells and tumors. Furthermore, sulindac dramatically reduces VEGF levels in the presence of IL-2-stimulated NK cells, indicating an improved immune response against tumor cells. Even the immunological suppression caused by tumor cells stimulated with TNF-α is reversed by sulindac. Consequently, the combination of sulindac with chemotherapy can effectively inhibit tumor growth and increase resistance to oral malignancies.