In the tumor microenvironment, metabolic reprogramming can impact metabolic characteristics of T cells, thus inducing immunosuppression to promote tumor immune escape. The mammalian target of rapamycin (mTOR) signaling pathway plays an important role in regulating diverse functions of various immune cells. This review mainly focuses on the molecular mechanism of mTOR signaling in regulating cellular energy metabolism process, and the activation status of mTOR signaling under different nutritional environments. In addition, it also summarizes the role of the mTOR signaling in regulatory T cell (Tregs) metabolism and function in current studies, and evaluates the potential of mTOR as a clinical immunotherapeutic target and its current application challenges.
Immunosuppression Therapy ; Metabolic Reprogramming ; Signal Transduction ; Sirolimus ; T-Lymphocytes, Regulatory ; TOR Serine-Threonine Kinases ; Humans

OBJECTIVE: To investigate the effect and possible mechanism of hydroxysafflor yellow A (HSYA) on human immortalized keratinocyte cell proliferation and migration. METHODS: HaCaT cells were treated with HSYA. Cell proliferation was detected by the cell counting kit-8 assay, and cell migration was measured using wound healing assay and Transwell migration assay. The mRNA and protein expression levels of heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF), EGF receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), protein kinase B (AKT), mammalian target of rapamycin (mTOR), and hypoxia-inducible factor-1α (HIF-1α) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot, respectively. Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA. The expression of circ_0084443 was detected by qRT-PCR. RESULTS: HSYA (800 µmol/L) significantly promoted HaCaT cell proliferation and migration (P<0.05 or P<0.01). It also increased the mRNA and protein expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and increased the phosphorylation levels of PI3K and AKT (P<0.05 or P<0.01). Furthermore, HSYA promoted HaCaT cell proliferation and migration via the HBEGF/EGFR and PI3K/AKT/mTOR signaling pathways (P<0.01). Circ_0084443 attenuated the mRNA expression levels of HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α (P<0.05). HSYA inhibited the circ_0084443 expression, further antagonized the inhibition of circ_0084443 on HBEGF, EGFR, PI3K, AKT, mTOR and HIF-1α, and promoted the proliferation of circ_0084443-overexpressing HaCaT cells (P<0.05 or P<0.01). However, HSYA could not influence the inhibitory effect of circ_0084443 on HaCaT cell migration (P>0.05). CONCLUSION HSYA played an accelerative role in HaCaT cell proliferation and migration, which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways, and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Phosphatidylinositol 3-Kinase ; Phosphatidylinositol 3-Kinases/metabolism* ; ErbB Receptors/genetics* ; TOR Serine-Threonine Kinases/metabolism* ; Cell Proliferation ; RNA, Messenger/genetics* ; Cell Movement ; Cell Line, Tumor ; Chalcone/analogs & derivatives* ; Quinones

OBJECTIVE: To explore the mechanism of electroacupuncture (EA) in promoting recovery of the facial function with the involvement of autophagy, glial cell line-derived neurotrophic factor (GDNF), and phosphatidylinositol-3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway. METHODS: Seventy-two male Sprague-Dawley rats were randomly allocated into the control, sham-operated, facial nerve injury (FNI), EA, EA+3-methyladenine (3-MA), and EA+GDNF antagonist groups using a random number table, with 12 rats in each group. An FNI rat model was established with facial nerve crushing method. EA intervention was conducted at Dicang (ST 4), Jiache (ST 6), Yifeng (SJ 17), and Hegu (LI 4) acupoints for 2 weeks. The Simone's 10-Point Scale was utilized to monitor the recovery of facial function. The histopathological evaluation of facial nerves was performed using hematoxylin-eosin (HE) staining. The levels of Beclin-1, light chain 3 (LC3), and P62 were detected by immunohistochemistry (IHC), immunofluorescence, and reverse transcription-polymerase chain reaction, respectively. Additionally, IHC was also used to detect the levels of GDNF, Rai, PI3K, and mTOR. RESULTS: The facial functional scores were significantly increased in the EA group than the FNI group (P<0.05 or P<0.01). HE staining showed nerve axons and myelin sheaths, which were destroyed immediately after the injury, were recovered with EA treatment. The expressions of Beclin-1 and LC3 were significantly elevated and the expression of P62 was markedly reduced in FNI rats (P<0.01); however, EA treatment reversed these abnormal changes (P<0.01). Meanwhile, EA stimulation significantly increased the levels of GDNF, Rai, PI3K, and mTOR (P<0.01). After exogenous administration with autophagy inhibitor 3-MA or GDNF antagonist, the repair effect of EA on facial function was attenuated (P<0.05 or P<0.01). CONCLUSIONS EA could promote the recovery of facial function and repair the facial nerve damages in a rat model of FNI. EA may exert this neuroreparative effect through mediating the release of GDNF, activating the PI3K/mTOR signaling pathway, and further regulating the autophagy of facial nerves.
Rats ; Male ; Animals ; Rats, Sprague-Dawley ; Electroacupuncture ; Phosphatidylinositol 3-Kinase/metabolism* ; Facial Nerve Injuries/therapy* ; Phosphatidylinositol 3-Kinases/metabolism* ; Beclin-1 ; Glial Cell Line-Derived Neurotrophic Factor ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism* ; Autophagy ; Mammals/metabolism*

Existing studies have underscored the pivotal role of N-acetyltransferase 10 (NAT10) in various cancers. However, the outcomes of protein-protein interactions between NAT10 and its protein partners in head and neck squamous cell carcinoma (HNSCC) remain unexplored. In this study, we identified a significant upregulation of RNA-binding protein with serine-rich domain 1 (RNPS1) in HNSCC, where RNPS1 inhibits the ubiquitination degradation of NAT10 by E3 ubiquitin ligase, zinc finger SWIM domain-containing protein 6 (ZSWIM6), through direct protein interaction, thereby promoting high NAT10 expression in HNSCC. This upregulated NAT10 stability mediates the enhancement of specific tRNA ac⁴C modifications, subsequently boosting the translation process of genes involved in pathways such as IL-6 signaling, IL-8 signaling, and PTEN signaling that play roles in regulating HNSCC malignant progression, ultimately influencing the survival and prognosis of HNSCC patients. Additionally, we pioneered the development of TRMC-seq, leading to the discovery of novel tRNA-ac⁴C modification sites, thereby providing a potent sequencing tool for tRNA-ac⁴C research. Our findings expand the repertoire of tRNA ac⁴C modifications and identify a role of tRNA ac⁴C in the regulation of mRNA translation in HNSCC.
Humans ; DNA-Binding Proteins ; Head and Neck Neoplasms/genetics* ; N-Terminal Acetyltransferases ; RNA, Transfer ; Serine ; Signal Transduction ; Squamous Cell Carcinoma of Head and Neck

Previous studies have shown that high blood glucose-induced chronic microinflammation can cause inflammatory podocyte injury in patients with diabetic kidney disease(DKD). Therein, necroptosis is a new form of podocyte death that is closely associated with renal fibrosis(RF). To explore the effects and mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese herbal medicine Abelmoschus manihot for treating kidney diseases, on podocyte necroptosis and RF in DKD, and to further reveal its scientific connotation with multi-pathway and multi-target, the authors randomly divided all rats into four groups: a namely normal group, a model group, a TFA group and a rapamycin(RAP) group. After the modified DKD rat models were successfully established, four group rats were given double-distilled water, TFA suspension and RAP suspension, respectively by gavage every day. At the end of the 4th week of drug treatment, all rats were sacrificed, and the samples of their urine, blood and kidneys were collected. And then, the various indicators related to podocyte necroptosis and RF in the DKD model rats were observed, detected and analyzed, respectively. The results indicated that, general condition, body weight(BW), serum creatinine(Scr), urinary albumin(UAlb), and kidney hypertrophy index(KHI) in these modified DKD model rats were both improved by TFA and RAP. Indicators of RF, including glomerular histomorphological characteristics, fibronectin(FN) and collagen type Ⅰ(collagen Ⅰ) staining extent in glomeruli, as well as the protein expression levels of FN, collagen Ⅰ, transforming growth factor-β1(TGF-β1) and Smad2/3 in the kidneys were improved respectively by TFA and RAP. Podocyte damage, including foot process form and the protein expression levels of podocin and CD2AP in the kidneys was improved by TFA and RAP. In addition, tumor necrosis factor-α(TNF-α)-mediated podocyte necroptosis in the kidneys, including the morphological characteristics of podocyte necroptosis, the extent and levels of the protein expression of TNF-α and phosphorylated mixed lineage kinase domain like pseudokinase(p-MLKL) was improved respectively by TFA and RAP. Among them, RAP had the better effect on p-MLKL. More importantly, the activation of the receptor interacting serine/threonine protein kinase 1(RIPK1)/RIPK3/MLKL signaling axis in the kidneys, including the expression levels of its key signaling molecules, such as phosphorylated receptor interacting serine/threonine protein kinase 1(p-RIPK1), p-RIPK3, p-MLKL and cysteinyl aspartate specific proteinase-8(caspase-8) was improved respectively by TFA and RAP. Among them, the effect of TFA on p-RIPK1 was superior. On the whole, in this study, the authors demonstrated that TFA alleviates podocyte necroptosis and RF in DKD through inhibiting the activation of the TNF-α-mediated RIPK1/RIPK3/MLKL signaling axis in diabetic kidneys. The authors' findings provide new pharmacological evidence to reveal the scientific connotation of TFA in treating RF in DKD in more depth.
Humans ; Rats ; Animals ; Diabetic Nephropathies/drug therapy* ; Abelmoschus ; Flavones/pharmacology* ; Podocytes ; Tumor Necrosis Factor-alpha/metabolism* ; Necroptosis ; Receptor-Interacting Protein Serine-Threonine Kinases/metabolism* ; Fibrosis ; Threonine/pharmacology* ; Collagen/metabolism* ; Serine/pharmacology* ; Diabetes Mellitus/drug therapy*

Based on the androgen receptor(AR)/mammalian target of rapamycin(mTOR)signaling pathway, the effects of Xihuang Pills-medicated serum on the proliferation and apoptosis of prostate cancer LNCaP cells were investigated. The drug-containing serum of SD rats was prepared by intragastric administration of Xihuang Pills suspension. The effects of low-, medium-, and high-dose Xihuang Pills-containing serum on the in vitro proliferation of LNCaP cells were detected by cell counting kit-8(CCK-8). Flow cytometry was used to detect the apoptosis level of LNCaP cells after intervention with different concentrations of Xihuang Pills. Protein expression of cleaved cysteinyl aspartate-specific proteinase caspase-3(cleaved caspase-3), B-cell lymphoma-2(Bcl-2), and AR as well as the phosphorylation level of mTOR protein were detected by Western blot. The results showed that compared with the blank serum, the drug-medicated serum could blunt the activity of LNCaP cells. Low-, medium-, and high-dose Xihuang Pills-containing serum could significantly increase the cell apoptosis rate, increase the expression of cleaved caspase-3 protein, decrease the expression of Bcl-2 protein, reduce the expression of AR protein, and down-regulate the level of phosphorylated mTOR(p-mTOR). To study the effect of Xihuang Pills on the growth of LNCaP cells in vivo, different doses of Xihuang Pills were used to intervene in the subcutaneous graft model in nude mice inoculated with LNCaP cells. The expression levels of AR, mTOR, p-mTOR, Bcl-2, and cleaved caspase-3 were detected by Western blot. The results showed that the volumes of subcutaneous graft tumor in the low-dose, medium-dose, and high-dose Xihuang Pills groups significantly decreased compared with that in the model group. The weight of subcutaneous transplanted tumor in each group with drug intervention was significantly lower than that in the model group. Compared with the model group, the low-dose, medium-dose, and high-dose Xihuang Pills groups showed increased cleaved caspase-3 protein expression, decreased Bcl-2 and AR protein expression, and reduced p-mTOR protein expression. Further experiments showed that AR agonist R1881 could block the anti-proliferation and pro-apoptotic effects of Xihuang Pills. The mechanism of Xihuang Pills against prostate cancer is related to the inhibition of the AR/mTOR signaling pathway, inhibition of LNCaP cell proliferation, and induction of apoptosis in cancer cells.
Humans ; Male ; Mice ; Rats ; Animals ; Caspase 3/metabolism* ; Mice, Nude ; Cell Line, Tumor ; Rats, Sprague-Dawley ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism* ; Prostatic Neoplasms/pathology* ; Cell Proliferation ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Mammals/metabolism*

This study explored the effects of Buyang Huanwu Decoction(BYHWD) on platelet activation and differential gene expression after acute myocardial infarction(AMI). SD rats were randomly divided into a sham-operated group, a model group, a positive drug(aspirin) group, and a BYHWD group. Pre-treatment was conducted for 14 days with a daily oral dose of 1.6 g·kg~(-1) BYHWD and 0.1 g·kg~(-1) aspirin. The AMI model was established using the high ligation of the left anterior descending coronary artery method. The detection indicators included myocardial infarct size, heart function, myocardial tissue pathology, peripheral blood flow perfusion, platelet aggregation rate, platelet membrane glycoprotein CD62p expression, platelet transcriptomics, and differential gene expression. The results showed that compared with the sham-operated group, the model group showed reduced ejection fraction and cardiac output, decreased peripheral blood flow, and increased platelet aggregation rate and CD62p expression, and activated platelets. At the same time, TXB_2 content increased and 6-keto-PGF1α content decreased in serum. Compared with the model group, BYHWD increased ejection fraction and cardiac output, improved blood circulation in the foot and tail regions and cardiomyocytes arrangement, reduced myocardial infarct size and inflammatory infiltration, down-regulated platelet aggregation rate and CD62p expression, reduced serum TXB_2 content, and increased 6-keto-PGF1α content. Platelet transcriptome sequencing results revealed that BYHWD regulated mTOR-autophagy pathway-related genes in platelets. The differential gene expression levels were detected using real-time quantitative PCR. BYHWD up-regulated mTOR, down-regulated autophagy-related FUNDC1 and PINK genes, and up-regulated p62 gene expression. The results demonstrated that BYHWD could regulate platelet activation, improve blood circulation, and protect ischemic myocardium in AMI rats, and its mechanism is related to the regulation of the mTOR-autophagy pathway in platelets.
Rats ; Animals ; Rats, Sprague-Dawley ; Drugs, Chinese Herbal/therapeutic use* ; Myocardial Infarction/genetics* ; Myocardium/metabolism* ; Aspirin/therapeutic use* ; TOR Serine-Threonine Kinases/metabolism* ; Membrane Proteins/metabolism* ; Mitochondrial Proteins

This study aimed to investigate the effect and molecular mechanism of sinomenine on proliferation, apoptosis, metastasis, and combination with inhibitors in human hepatocellular carcinoma HepG2 cells and SK-HEP-1 cells. The effect of sinomenine on the growth ability of HepG2 and SK-HEP-1 cells were investigated by CCK-8 assay, colony formation assay, and BeyoClick~(TM) EdU-488 staining. The effect of sinomenine on DNA damage was detected by immunofluorescence assay, and the effect of sinomenine on apoptosis of human hepatocellular carcinoma cells was clarified by Hoechst 33258 staining and CellEvent~(TM) Cystein-3/7Green ReadyProbes~(TM) reagent assay. Cell invasion assay and 3D tumor cell spheroid invasion assay were performed to investigate the effect of sinomenine on the invasion ability of human hepatocellular carcinoma cells in vitro. The effect of sinomenine on the regulation of protein expression related to the protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription 3(STAT3) signaling pathway in HepG2 and SK-HEP-1 cells was examined by Western blot. Molecular docking was used to evaluate the strength of affinity of sinomenine to the target cysteinyl aspartate specific proteinase-3(caspase-3) and STAT3, and combined with CCK-8 assay to detect the changes in cell viability after combination with STAT3 inhibitor JSI-124 in combination with CCK-8 assay. The results showed that sinomenine could significantly reduce the cell viability of human hepatocellular carcinoma cells in a concentration-and time-dependent manner, significantly inhibit the clonogenic ability of human hepatocellular carcinoma cells, and weaken the invasive ability of human hepatocellular carcinoma cells in vitro. In addition, sinomenine could up-regulate the cleaved level of poly ADP-ribose polymerase(PARP), a marker of apoptosis, and down-regulate the protein levels of p-Akt, p-mTOR, and p-STAT3 in human hepatocellular carcinoma cells. Molecular docking results showed that sinomenine had good affinity with the targets caspase-3 and STAT3, and the sensitivity of sinomenine to hepatocellular carcinoma cells was diminished after STAT3 was inhibited. Therefore, sinomenine can inhibit the proliferation and invasion of human hepatocellular carcinoma cells and induce apoptosis, and the mechanism may be attributed to the activation of caspase-3 signaling and inhibition of the Akt/mTOR/STAT3 pathway. This study can provide a new reference for the in-depth research and clinical application of sinomenine and is of great significance to further promote the scientific development and utilization of sinomenine.
Humans ; Carcinoma, Hepatocellular/genetics* ; Proto-Oncogene Proteins c-akt/metabolism* ; Caspase 3/metabolism* ; Liver Neoplasms/genetics* ; Molecular Docking Simulation ; Sincalide/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; Hep G2 Cells ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis

This study aims to investigate the mechanism of Astragali Radix-Curcumae Rhizoma(HQEZ) in the treatment of gastric cancer based on network pharmacology. Further, the SGC7901 cell model of gastric cancer was employed to validate the efficacy and key targets of the herb pair. Firstly, the CCK-8 assay was employed to evaluate the direct effect of HQEZ on the proliferation of gastric cancer SGC7901 cells. Then, network pharmacology methods were employed to investigate the active ingredients, key targets, and key signaling pathways involved in the treatment of gastric cancer with HQEZ. The results showed that HQEZ contained 18 potential active ingredients, such as quercetin, naringenin, and curcumin. The results of gene ontology(GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment suggested that the main targets of HQEZ in treating gastric cancer were involved in the regulation of protein serine/threonine kinase activity, activation of mitogen-activated protein kinase(MAPK) activity, cysteine-type endopeptidase activity, and negative regulation of protein serine/threonine kinase activity. The hypoxia-inducible factor-1(HIF-1) signaling pathway, ATP-binding cassette(ABC) transporters, cytochrome P450-mediated metabolism of xenobiotics, p53 signaling pathway, and cell apoptosis were key signaling pathways of HQEZ in treating gastric cancer. The cell experiments demonstrated that HQEZ significantly downregulated the expression of ATP-binding cassette subfamily B member 1(ABCB1), epidermal growth factor receptor(EGFR), phosphorylated serine/threonine kinase(p-AKT), hypoxia inducible factor 1 subunit alpha(HIF1A), B-cell lymphoma 2(BCL2), breast cancer susceptibility protein 1(BRCA1), DNA polymerase theta(POLH), ribonucleotide reductase M1(RRM1), and excision repair cross-complementation group 1(ERCC1), and upregulated the expression of tumor protein P53(TP53) and cysteinyl aspartate-specific proteinase(CAPS3). Finally, a multivariate COX regression model was adopted to study the relationship between gene expression and clinical information data of gastric cancer patients in the TCGA database, which demonstrated that the key targets of HQEZ were associated with the poor prognosis in gastric cancer patients. Further feature selection using the LASSO algorithm showed that EGFR, HIF1A, TP53, POLH, RRM1, and ERCC1 were closely associated with the survival of gastric can-cer patients. In conclusion, HQEZ regulates the expression of genes involved in DNA repair, survival, and apoptosis in gastric cancer cells via multiple targets and pathways, assisting the treatment of gastric cancer.
Humans ; Stomach Neoplasms/genetics* ; Tumor Suppressor Protein p53 ; Network Pharmacology ; ErbB Receptors ; Protein Serine-Threonine Kinases ; Serine ; Adenosine Triphosphate ; Molecular Docking Simulation ; Drugs, Chinese Herbal/pharmacology*

This study investigated the effect and mechanism of morin in inducing autophagy and apoptosis in hepatocellular carcinoma cells through the protein kinase B(Akt)/mammalian target of rapamycin(mTOR)/signal transducer and activator of transcription protein 3(STAT3) pathway. Human hepatocellular carcinoma SK-HEP-1 cells were stimulated with different concentrations of morin(0, 50, 100, 125, 200, and 250 μmol·L~(-1)). The effect of morin on the viability of SK-HEP-1 cells was detected by Cell Counting Kit-8(CCK-8). The effect of morin on the proliferation and apoptosis of SK-HEP-1 cells was investigated using colony formation assay, flow cytometry, and BeyoClick~(TM) EdU-488 with different concentrations of morin(0, 125, and 250 μmol·L~(-1)). The changes in the autophagy level of cells treated with morin were examined by transmission electron microscopy and autophagy inhibitors. The impact of morin on the expression levels of proteins related to the Akt/mTOR/STAT3 pathway was verified by Western blot. Compared with the control group, the morin groups showed decreased viability of SK-HEP-1 cells in a time-and concentration-dependent manner, increased number of apoptotic cells, up-regulated expression level of apoptosis marker PARP, up-regulated phosphorylation level of apoptosis-regulating protein H2AX, decreased number of positive cells and the colony formation rate, an upward trend of expression levels of autophagy-related proteins LC3-Ⅱ, Atg5, and Atg7, and decreased phosphorylation levels of Akt, mTOR, and STAT3. These results suggest that morin can promote apoptosis, inhibit proliferation, and induce autophagy in hepatocellular carcinoma cells, and its mechanism of action may be related to the Akt/mTOR/STAT3 pathway.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Carcinoma, Hepatocellular/pathology* ; Liver Neoplasms/pathology* ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis ; Autophagy ; Cell Proliferation ; Cell Line, Tumor ; STAT3 Transcription Factor/metabolism*