Abstract：
BACKGROUND: Hepatocellular carcinoma (HCC), the most primary malignant liver tumor and is ranked as the fifth most common malignancy worldwide. Despite various therapeutic approaches being used in clinical practice, the overall effectiveness remains insufficient. Stigmasterol, a compound known for its anti-tumor properties and ability to induce apoptosis in tumor cells, has been found to influenced the composition of the intestinal microbiota. However, the mechanism through which stigmasterol influences the intestinal microbial-host crosstalk in HCC remains elusive.
OBJECTIVE: This study was to investigate whether stigmasterol can remodel gut microbiota, and suppress tumor volume by regulating Treg and IFN-γ+ CD8+ cell in the host with HCC.
METHODS: Stigmasterol (at dosages of 0, 50, 100, or 200 mg/kg) was orally administered to Balb/c mice with subcutaneous tumor once every 2 days for 3 weeks.
RESULTS: We first found that tumors volume in the group treated with 100 mg/kg stigmasterol were significantly decreased compared with those in the control group (P < 0.05), which exhibited a similar effect as the sorafenib treatment in mice with HCC. This resulted in a significant upregulation of Caspase3, Bax, and P53 expressions, as well as a decrease in Cyclin D1 expression, ultimately leading to a reduction in tumor volume. Additionally, stigmasterol can alter the α and β diversity of the intestinal flora and significantly increase the abundance of Lactobacillus_johnsonii, Lactobacillus_murinus, and Lactobacillus_reuteri (P<0.05), which can lead to a decrease in the ratio of regulatory T cells (Tregs) to CD8+ T cells in the intestinal tract and tumor tissue, and consequently enhance immune response in the tumor microenvironment (TME) in the host with HCC.
CONCLUSIONS: In this study, we initially utilized different dosages of stigmasterol to intervene in mice with HCC and confirmed its inhibitory effects on tumor growth in vivo, and discovered that stigmasterol affected Lactobacillus johnsonii, Lactobacillus murinus, and Lactobacillus reuteri, resulting in an increased proportion of IFN-γ+ CD8+ T cells and Treg cells in both the intestinal mucosa and tumor tissues, and ultimately leading to increased levels of apoptotic proteins and the subsequent death of tumor cells, which shed light on the effect of stigmasterol on host intestinal tissue and intratumoral immune cells by reshaping the intestinal microbiota, and provide a theoretical foundation for the potential clinical application of stigmasterol in the treatment of HCC.
OBJECTIVE: This study was to investigate whether stigmasterol can remodel gut microbiota, and suppress tumor volume by regulating Treg and IFN-γ+ CD8+ cell in the host with HCC.
METHODS: Stigmasterol (at dosages of 0, 50, 100, or 200 mg/kg) was orally administered to Balb/c mice with subcutaneous tumor once every 2 days for 3 weeks.
RESULTS: We first found that tumors volume in the group treated with 100 mg/kg stigmasterol were significantly decreased compared with those in the control group (P < 0.05), which exhibited a similar effect as the sorafenib treatment in mice with HCC. This resulted in a significant upregulation of Caspase3, Bax, and P53 expressions, as well as a decrease in Cyclin D1 expression, ultimately leading to a reduction in tumor volume. Additionally, stigmasterol can alter the α and β diversity of the intestinal flora and significantly increase the abundance of Lactobacillus_johnsonii, Lactobacillus_murinus, and Lactobacillus_reuteri (P<0.05), which can lead to a decrease in the ratio of regulatory T cells (Tregs) to CD8+ T cells in the intestinal tract and tumor tissue, and consequently enhance immune response in the tumor microenvironment (TME) in the host with HCC.
CONCLUSIONS: In this study, we initially utilized different dosages of stigmasterol to intervene in mice with HCC and confirmed its inhibitory effects on tumor growth in vivo, and discovered that stigmasterol affected Lactobacillus johnsonii, Lactobacillus murinus, and Lactobacillus reuteri, resulting in an increased proportion of IFN-γ+ CD8+ T cells and Treg cells in both the intestinal mucosa and tumor tissues, and ultimately leading to increased levels of apoptotic proteins and the subsequent death of tumor cells, which shed light on the effect of stigmasterol on host intestinal tissue and intratumoral immune cells by reshaping the intestinal microbiota, and provide a theoretical foundation for the potential clinical application of stigmasterol in the treatment of HCC.
摘要：
背景：肝细胞癌（HCC），最主要的恶性肝脏肿瘤，并被列为全球第五大最常见的恶性肿瘤。尽管在临床实践中使用了各种治疗方法，总体效果仍然不足。豆甾醇,一种以其抗肿瘤特性和诱导肿瘤细胞凋亡的能力而闻名的化合物，已发现影响肠道微生物群的组成。然而,在HCC中，豆甾醇影响肠道微生物-宿主串扰的机制仍然难以捉摸。
目的：本研究旨在研究豆甾醇是否可以重塑肠道菌群，并通过调节肝癌宿主中的Treg和IFN-γCD8细胞来抑制肿瘤体积。
方法:将豆甾醇(以0、50、100或200mg/kg的剂量)口服给予具有皮下肿瘤的Balb/c小鼠,每2天一次,持续3周。
结果：我们首先发现100mg/kg豆甾醇治疗组的肿瘤体积比对照组明显减少（P<0.05）。在肝癌小鼠中表现出与索拉非尼治疗相似的效果。这导致Caspase3，Bax，和P53表达式，以及细胞周期蛋白D1表达的减少，最终导致肿瘤体积减小。此外,豆甾醇可以改变肠道菌群的α和β多样性，显著增加约氏乳杆菌的丰度，乳杆菌_murinus，和罗伊氏乳杆菌(P<0.05)，这可能导致肠道和肿瘤组织中调节性T细胞（Tregs）与CD8+T细胞的比例降低，并因此增强HCC宿主中肿瘤微环境（TME）的免疫反应。
结论：在这项研究中，我们最初利用不同剂量的豆甾醇干预小鼠肝癌，并证实其在体内对肿瘤生长的抑制作用，发现豆甾醇影响了约翰森氏乳杆菌，鼠乳杆菌,和罗伊氏乳杆菌,导致肠粘膜和肿瘤组织中IFN-γ+CD8+T细胞和Treg细胞的比例增加，并最终导致凋亡蛋白水平升高和随后的肿瘤细胞死亡，通过重塑肠道菌群，揭示了豆甾醇对宿主肠道组织和肿瘤内免疫细胞的影响，为豆甾醇在肝癌治疗中的潜在临床应用提供理论依据。
目的：本研究旨在研究豆甾醇是否可以重塑肠道菌群，并通过调节肝癌宿主中的Treg和IFN-γCD8细胞来抑制肿瘤体积。
方法:将豆甾醇(以0、50、100或200mg/kg的剂量)口服给予具有皮下肿瘤的Balb/c小鼠,每2天一次,持续3周。
结果：我们首先发现100mg/kg豆甾醇治疗组的肿瘤体积比对照组明显减少（P<0.05）。在肝癌小鼠中表现出与索拉非尼治疗相似的效果。这导致Caspase3，Bax，和P53表达式，以及细胞周期蛋白D1表达的减少，最终导致肿瘤体积减小。此外,豆甾醇可以改变肠道菌群的α和β多样性，显著增加约氏乳杆菌的丰度，乳杆菌_murinus，和罗伊氏乳杆菌(P<0.05)，这可能导致肠道和肿瘤组织中调节性T细胞（Tregs）与CD8+T细胞的比例降低，并因此增强HCC宿主中肿瘤微环境（TME）的免疫反应。
结论：在这项研究中，我们最初利用不同剂量的豆甾醇干预小鼠肝癌，并证实其在体内对肿瘤生长的抑制作用，发现豆甾醇影响了约翰森氏乳杆菌，鼠乳杆菌,和罗伊氏乳杆菌,导致肠粘膜和肿瘤组织中IFN-γ+CD8+T细胞和Treg细胞的比例增加，并最终导致凋亡蛋白水平升高和随后的肿瘤细胞死亡，通过重塑肠道菌群，揭示了豆甾醇对宿主肠道组织和肿瘤内免疫细胞的影响，为豆甾醇在肝癌治疗中的潜在临床应用提供理论依据。
