[The role of TMPRSS2 in tumor development and viral infection].

TMPRSS2 is a member of a family of proteins localized to the cell membrane and characterized by a conserved serine protease domain. Previous studies have demonstrated its involvement in the initiation and progression of various cancers in the human body. Its serine protease activity can degrade extracellular matrix components, disrupt the integrity of the basement membrane, and promote tumor cell invasion and metastasis. In addition, its expression level is closely related to the degree of immune cell infiltration and may affect tumor immune escape by regulating local inflammatory responses. In terms of viral infection, TMPRSS2 also plays a critical role, especially in the process of coronavirus infection, where it can stimulate the activation of viral particles and enhance infection. Recent studies on COVID-19 have further shown that TMPRSS2-mediated cleavage of the viral spike protein is essential for the activation and entry of the SARS-CoV-2 into the host cells. This review summarizes the current understanding of the structure and function of TMPRSS2, as well as its role in SARS-CoV-2 infection, with the aim of elucidating the underlying mechanisms by which TMPRSS2 facilitates viral entry and propagation within the host. These insights may contribute to the development of targeted therapeutics and vaccines.