DDX5 Functions as a Tumor Suppressor in Tongue Cancer

Simple Summary In this study, we demonstrate that DDX5 serves as a tumor suppressor in the specific context of tongue cancer, which is contrary to its documented oncogenic role in a vast array of cancers. The high expression of DDX5 in tongue cancer is correlated with a better prognosis in clinical patients. The knockdown of DDX5 promotes, while the overexpression of DDX5 inhibits, tongue cancer proliferation, development, and cisplatin resistance. Moreover, we found that the expression of DDX5 in tongue cancer is associated with immune cell infiltration in the tumor microenvironment. Specifically, the expression of DDX5 is associated with a reduced infiltration of M2 macrophages and an increased infiltration of T cell clusters, which may contribute to anticancer effects in the tumor microenvironment. Our study establishes DDX5 as a valuable prognostic biomarker and an important tumor suppressor in tongue cancer.Abstract DEAD-box polypeptide 5 (DDX5), a DEAD-box RNA helicase, is a multifunctional protein that plays important roles in many physiological and pathological processes. Contrary to its documented oncogenic role in a wide array of cancers, we herein demonstrate that DDX5 serves as a tumor suppressor in tongue cancer. The high expression of DDX5 is correlated with better prognosis for clinical tongue cancer patients. DDX5 downregulates the genes associated with tongue cancer progression. The knockdown of DDX5 promotes, while the overexpression of DDX5 inhibits, tongue cancer proliferation, development, and cisplatin resistance. Furthermore, the expression of DDX5 in tongue cancer is associated with immune cell infiltration in the tumor microenvironment. Specifically, the expression of DDX5 is associated with the reduced infiltration of M2 macrophages and increased infiltration of T cell clusters, which may contribute to anticancer effects in the tumor microenvironment. In this study, we establish DDX5 as a valuable prognostic biomarker and an important tumor suppressor in tongue cancer.