Cell重磅：华人团队发现，这种常用抗抑郁药物，能够帮助免疫系统对抗癌症

Core Viewpoint - Immune checkpoint blockade (ICB) therapies have shown promise in cancer treatment, but their effectiveness is limited to less than 25% of patients, highlighting the need for new immune checkpoints to enhance T cell responses against tumors [1][2]. Group 1: Research Findings - A study published by a team from UCLA identified the serotonin transporter (SERT) as a new immune checkpoint that inhibits antitumor immunity [2]. - Selective serotonin reuptake inhibitors (SSRIs), commonly used antidepressants, significantly enhance T cell anti-cancer capabilities and suppress tumor growth in various cancer models [2][10]. - The research demonstrated that SSRIs reduced tumor size by over 50% on average and improved the effectiveness of T cells in killing cancer cells [10]. Group 2: Mechanism of Action - SERT depletes serotonin secreted by intratumoral T cells, thereby inhibiting CD8 T cell antitumor responses [11]. - SSRIs were found to work synergistically with anti-PD-1 monoclonal antibodies, a common ICB therapy, leading to significant tumor size reduction and even complete remission in some mouse models [16]. Group 3: Clinical Implications - Approximately 20% of cancer patients are on antidepressants, primarily SSRIs, presenting an opportunity to explore their impact on cancer treatment outcomes [18]. - The potential for SSRIs to enhance the efficacy of existing cancer therapies could lead to significant advancements in cancer immunotherapy [19]. - The cost of repurposing FDA-approved drugs like SSRIs for cancer treatment is significantly lower than developing new therapies, making this approach particularly promising [19].