Reduction of FoxP3<sup>+</sup> Tregs by an immunosuppressive protocol of rapamycin plus Thymalfasin and Huaier extract predicts positive survival benefits in a rat model of hepatocellular carcinoma.
Zhou. Lin L; Pan. Li-Chao LC; Zheng. Yong-Gen YG; Zhang. Xin-Xue XX; Liu. Zhi-Jia ZJ; Meng. Xuan X; Shi. Hai-Da HD; Du. Guo-Sheng GS; He. Qiang Q
Key Findings
- RapamycinâŻ+âŻthymosinâalphaâ1âŻ+âŻHuaier extract sharply reduced FoxP3âș Treg numbers in blood, spleen, and liver
- CD8âș Tâcell levels rose toward normal, correlating with better survival
- Serum AFP and VEGF, plus inhibitory cytokines ILâ10 and TGFâÎČ, fell significantly
Practical Outcomes
- The study hints that thymosinâalphaâ1 could complement rapamycin to shift immunity away from suppression toward antiâtumor activity, but itâs only been shown in rats with liver cancer. Biohackers should wait for human trials before trying this combo, and any use should be under medical guidance.
Summary
In a rat liverâcancer model, giving rapamycin together with the peptide thymosinâalphaâ1 (thymalfasin) and a mushroom extract lowered harmful regulatory Tâcells, boosted antiâtumor CD8âŻTâcells, and lengthened survival, likely by dampening the AKTâmTOR pathway. The work is preâclinical, so it shows a possible immuneâbalancing effect but isnât ready for direct human use.
Abstract
Investigate immunoregulation and anti-tumor immunity of FoxP3<sup>+</sup>Tregs after treatment with rapamycin (RAPA/SRL) plus thymalfasin (Zadaxin) and Huaier extract (PS-T) in a hepatocellular carcinoma (HCC) rat model simulating HCC relapse after liver transplant (LT). We successfully established a rat model simulating HCC relapse after LT using an optimized chemical induction method with TACROLIMUS, methylprednisolone, and diethylnitrosamine as identified by visible liver nodules and hematoxylin-eosin staining. The model rats were then treated with RAPA, Zadaxin, and PS-T. Immune status changes were analyzed by flow cytometry, and protein expression of Akt and mTOR was determined by western blotting. Cytokines were measured by ELISAs. Combined therapy by RAPA plus Zadaxin and PS-T obviously alleviated hepatic pathological changes and significantly decreased the levels of FoxP3<sup>+</sup>Tregs in peripheral blood, the spleen, and the liver (P<0.05) and expression of mTOR protein (P<0.01) in the liver, obviously improved survival time (P=0.02). Moreover, the levels of CD8<sup>+</sup>T cells were increased significantly to almost normal levels (P<0.05) in comparison with no SRL monotherapy protocols. Inhibitory cytokines were also decreased in accordance with FoxP3<sup>+</sup>Tregs. Significant decreases of IL-10 and TGF-β were observed after SRL-based therapy (P<0.01) in comparison with the other groups. Serum alpha fetoprotein (AFP) and vascular endothelial growth factor (VEGF) levels were also decreased significantly (P<0.05). FoxP3<sup>+</sup>Tregs showed a negative correlation with CD8<sup>+</sup> and CD4<sup>+</sup>/CD8<sup>+</sup>T cells and a positive correlation with AFP, and VEGF (P<0.05). SRL-based therapy reduces FoxP3<sup>+</sup>Tregs to decrease secreted inhibitory cytokines which may enhancement the viability and number of CD8<sup>+</sup>T cells to exert anti-tumor effects that are mainly mediated through the AKT-mTOR signaling pathway.
Study Information
pubmed
2020
2020-04-01T00:00:00.000Z
10.21037/atm.2020.03.129
12
67