癌症相关成纤维细胞（CAF）是肿瘤微环境（TME）中最丰富的基质细胞成分。 CAF 有助于肿瘤发生，并已被提议作为抗癌治疗的靶标。同样，SUMO 机械部件的失调会破坏 SUMO 化的平衡，从而导致包括乳腺癌在内的各种癌症的肿瘤发生和耐药性。我们探索了 SUMOylation 在乳腺 CAF 中的作用，并评估了其作为乳腺癌治疗策略的潜力。我们使用药理学和遗传学方法来分析乳腺肿瘤细胞和 CAF 之间的功能串扰。我们用两种不同浓度的 SUMO1 抑制剂银杏酸 (GA) 处理乳腺 CAF，并使用条件培养基分析不同分子亚型乳腺癌细胞的增殖、迁移和侵袭。此外，我们还进行了定量蛋白质组学 (SILAC)，以研究低浓度或高浓度 GA 处理的 CAF 中表达的差异信号通路。我们在体外和体内证实了这些结果。此外，我们使用来自转移性乳腺癌患者的样本来评估 GA 作为治疗策略的使用。银杏酸 (GA) 抑制 SUMO 化会诱导乳腺癌细胞死亡，但不会影响 CAF 的活力，表明 CAF 具有耐药性到这种疗法。虽然 CAF 活力不受影响，但 CAF 条件培养基 (CM) 会被 GA 改变，以不同方式影响肿瘤细胞行为，具体取决于 SUMO1-SUMO 化蛋白失调的总体程度。乳腺癌细胞系对来自 CAF 的条件培养基 (CM) 表现出浓度依赖性反应。在低浓度 GA (10 µM) 下，乳腺癌细胞的增殖、迁移和侵袭有所增加。然而，在较高浓度的 GA (30 µM) 下，这些过程受到抑制。同样，肿瘤发育分析表明，与使用较高浓度 GA (30 µM) 治疗的肿瘤相比，10 µM GA 下的肿瘤更重，且转移程度更大。此外，其中一些效应可以通过 GTPase Rac1 活性的改变和 AKT 信号通路的激活来解释。使用 SILAC 获得的结果表明，不同浓度的 GA 对细胞过程的影响不同，可能影响 CAF 的分泌组。用 GA 治疗转移性乳腺癌证明可以使用 SUMO 化抑制作为替代治疗策略。该研究强调了 SUMO 化在肿瘤微环境中的重要性，特别是在癌症相关成纤维细胞 (CAF) 中。靶向 CAF 中的 SUMO 化会以浓度依赖性方式影响其信号通路和分泌组，从而调节 CAF 的促肿瘤特性。© 2024。作者。

Cancer-associated fibroblasts (CAFs) are the most abundant stromal cellular component in the tumor microenvironment (TME). CAFs contribute to tumorigenesis and have been proposed as targets for anticancer therapies. Similarly, dysregulation of SUMO machinery components can disrupt the balance of SUMOylation, contributing to tumorigenesis and drug resistance in various cancers, including breast cancer. We explored the role of SUMOylation in breast CAFs and evaluated its potential as a therapeutic strategy in breast cancer.We used pharmacological and genetic approaches to analyse the functional crosstalk between breast tumor cells and CAFs. We treated breast CAFs with the SUMO1 inhibitor ginkgolic acid (GA) at two different concentrations and conditioned media was used to analyse the proliferation, migration, and invasion of breast cancer cells from different molecular subtypes. Additionally, we performed quantitative proteomics (SILAC) to study the differential signalling pathways expressed in CAFs treated with low or high concentrations of GA. We confirmed these results both in vitro and in vivo. Moreover, we used samples from metastatic breast cancer patients to evaluate the use of GA as a therapeutic strategy.Inhibition of SUMOylation with ginkgolic acid (GA) induces death in breast cancer cells but does not affect the viability of CAFs, indicating that CAFs are resistant to this therapy. While CAF viability is unaffected, CAF-conditioned media (CM) is altered by GA, impacting tumor cell behaviour in different ways depending on the overall degree to which SUMO1-SUMOylated proteins are dysregulated. Breast cancer cell lines exhibited a concentration-dependent response to conditioned media (CM) from CAFs. At a low concentration of GA (10 µM), there was an increase in proliferation, migration and invasion of breast cancer cells. However, at a higher concentration of GA (30 µM), these processes were inhibited. Similarly, analysis of tumor development revealed that at 10 µM of GA, the tumors were heavier and there was a greater degree of metastasis compared to the tumors treated with the higher concentration of GA (30 µM). Moreover, some of these effects could be explained by an alteration in the activity of the GTPase Rac1 and the activation of the AKT signalling pathway. The results obtained using SILAC suggest that different concentrations of GA affected cellular processes differentially, possibly influencing the secretome of CAFs. Treatment of metastatic breast cancer with GA demonstrated the use of SUMOylation inhibition as an alternative therapeutic strategy.The study highlights the importance of SUMOylation in the tumor microenvironment, specifically in cancer-associated fibroblasts (CAFs). Targeting SUMOylation in CAFs affects their signalling pathways and secretome in a concentration-dependent manner, regulating the protumorigenic properties of CAFs.© 2024. The Author(s).