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

OBJECTIVE: To investigate the influence and mechanism of atorvastatin on glycolysis of adriamycin resistant acute promyelocytic leukemia (APL) cell line HL-60/ADM. METHODS: HL-60/ADM cells in logarithmic growth phase were treated with different concentrations of atorvastatin, then the cell proliferation activity was measured by CCK-8 assay, the apoptosis was detected by flow cytometry, the glycolytic activity was checked by glucose consumption test, and the protein expressions of PTEN, p-mTOR, PKM2, HK2, P-gp and MRP1 were detected by Western blot. After transfection of PTEN-siRNA into HL-60/ADM cells, the effects of low expression of PTEN on atorvastatin regulating the behaviors of apoptosis and glycolytic metabolism in HL-60/ADM cells were further detected. RESULTS: CCK-8 results showed that atorvastatin could inhibit the proliferation of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.872, r=0.936), and the proliferation activity was inhibited most significantly when treated with 10 μmol/L atorvastatin for 24 h, which was decreased to (32.3±2.18)%. Flow cytometry results showed that atorvastatin induced the apoptosis of HL-60/ADM cells in a concentration-dependent manner (r=0.796), and the apoptosis was induced most notably when treated with 10 μmol/L atorvastatin for 24 h, which reached to (48.78±2.95)%. The results of glucose consumption test showed that atorvastatin significantly inhibited the glycolytic activity of HL-60/ADM cells in a concentration-dependent and time-dependent manner (r=0.915, r=0.748), and this inhibition was most strikingly when treated with 10 μmol/L atorvastatin for 24 h, reducing the relative glucose consumption to (46.53±1.71)%. Western blot indicated that the expressions of p-mTOR, PKM2, HK2, P-gp and MRP1 protein were decreased in a concentration-dependent manner (r=0.737, r=0.695, r=0.829, r=0.781, r=0.632), while the expression of PTEN protein was increased in a concentration-dependent manner (r=0.531), when treated with different concentrations of atorvastatin for 24 h. After PTEN-siRNA transfected into HL-60/ADM cells, it showed that low expression of PTEN had weakened the promoting effect of atorvastatin on apoptosis and inhibitory effect on glycolysis and multidrug resistance. CONCLUSION Atorvastatin can inhibit the proliferation, glycolysis, and induce apoptosis of HL-60/ADM cells. It may be related to the mechanism of increasing the expression of PTEN, inhibiting mTOR activation, and decreasing the expressions of PKM2 and HK2, thus reverse drug resistance.
Humans ; Atorvastatin/pharmacology* ; PTEN Phosphohydrolase/pharmacology* ; Sincalide/metabolism* ; Drug Resistance, Neoplasm/genetics* ; TOR Serine-Threonine Kinases/metabolism* ; Leukemia, Promyelocytic, Acute/drug therapy* ; Doxorubicin/pharmacology* ; Apoptosis ; RNA, Small Interfering/pharmacology* ; Glycolysis ; Glucose/therapeutic use* ; Cell Proliferation

OBJECTIVE: To investigate the effects of mTOR inhibitors everolimus (EVE) and gemcitabine (GEM) on the proliferation, apoptosis and cell cycle of diffuse large B-cell lymphoma (DLBCL) cell line U2932, and further explore the molecular mechanisms, so as to provide new ideas and experimental basis for the clinical treatment of DLBCL. METHODS: The effect of EVE and GEM on the proliferation of U2932 cells was detected by CCK-8 assay, the IC₅₀ of the two drugs was calculated, and the combination index (CI=) of the two drugs was calculated by CompuSyn software. The effect of EVE and GEM on apoptosis of U2932 cells was detected by flow cytometry with AnnexinV-FITC/PI staining. Flow cytometry with propidium iodide (PI) staining was used to detect the effect of EVE and GEM on the cell cycle of U2932 cells. Western blot assay was used to detect the effects of EVE and GEM on the channel proteins p-mTOR and p-4EBP1, the anti-apoptotic proteins MCL-1 and Survivin, and the cell cycle protein Cyclin D1. RESULTS: Both EVE and GEM could significantly inhitbit the proliferation of U2932 cells in a time- and dose-dependent manner (r=0.465, 0.848; 0.555, 0.796). According to the calculation of CompuSyn software, EVE combined with GEM inhibited the proliferation of U2932 cells at 24, 48 and 72 h with CI=<1, which had a synergistic effect. After treated U2932 cells with 10 nmol/L EVE, 250 nmol/L GEM alone and in combination for 48 h, both EVE and GEM induced apoptosis, and the difference was statistically significant compared with the control group (P<0.05). The apoptosis rate was significantly enhanced after EVE in combination with GEM compared with single-agent (P<0.05). Both EVE and GEM alone and in combination significantly increased the proportion of cells in G₁ phase compared with the control group (P<0.05). The proportion of cells in G₁ phase was significantly increased when the two drugs were combined (P<0.05). The expression of p-mTOR and effector protein p-4EBP1 was significantly downregulated in the EVE combined with GEM group, the expression of anti-apoptotic proteins MCL-1, Survivin and cell cycle protein cyclin D1 was downregulated too (P<0.05). CONCLUSION EVE combined with GEM can synergistically inhibit the proliferation of U2932 cells, and the mechanism may be that they can synergistically induce apoptosis by downregulating the expression of MCL-1 and Survivin proteins and block the cell cycle progression by downregulating the expression of Cyclin D1.
Humans ; Gemcitabine ; Everolimus/pharmacology* ; Survivin/pharmacology* ; Cyclin D1/pharmacology* ; Myeloid Cell Leukemia Sequence 1 Protein ; Cell Line, Tumor ; Cell Proliferation ; TOR Serine-Threonine Kinases ; Apoptosis ; Apoptosis Regulatory Proteins ; Cell Cycle Proteins ; Lymphoma, Large B-Cell, Diffuse

BACKGROUND: Juvenile amyotrophic lateral sclerosis (JALS) is an uncommon form of amyotrophic lateral sclerosis whose age at onset (AAO) is defined as prior to 25 years. FUS mutations are the most common cause of JALS. SPTLC1 was recently identified as a disease-causative gene for JALS, which has rarely been reported in Asian populations. Little is known regarding the difference in clinical features between JALS patients carrying FUS and SPTLC1 mutations. This study aimed to screen mutations in JALS patients and to compare the clinical features between JALS patients with FUS and SPTLC1 mutations. METHODS: Sixteen JALS patients were enrolled, including three newly recruited patients between July 2015 and August 2018 from the Second Affiliated Hospital, Zhejiang University School of Medicine. Mutations were screened by whole-exome sequencing. In addition, clinical features such as AAO, onset site and disease duration were extracted and compared between JALS patients carrying FUS and SPTLC1 mutations through a literature review. RESULTS: A novel and de novo SPTLC1 mutation (c.58G>A, p.A20T) was identified in a sporadic patient. Among 16 JALS patients, 7/16 carried FUS mutations and 5/16 carried respective SPTLC1 , SETX , NEFH , DCTN1 , and TARDBP mutations. Compared with FUS mutation patients, those with SPTLC1 mutations had an earlier AAO (7.9 ± 4.6 years vs. 18.1 ± 3.9 years, P  < 0.01), much longer disease duration (512.0 [416.7-607.3] months vs. 33.4 [21.6-45.1] months, P  < 0.01), and no onset of bulbar. CONCLUSION Our findings expand the genetic and phenotypic spectrum of JALS and help to better understand the genotype-phenotype correlation of JALS.
Humans ; Amyotrophic Lateral Sclerosis/genetics* ; DNA Helicases/genetics* ; Genetic Association Studies ; Multifunctional Enzymes/genetics* ; Mutation/genetics* ; RNA Helicases/genetics* ; RNA-Binding Protein FUS/genetics* ; Serine C-Palmitoyltransferase/genetics* ; Child, Preschool ; Child ; Adolescent ; Young Adult

OBJECTIVE: This study investigated the effects of bis (2-butoxyethyl) phthalate (BBOP) on the onset of male puberty by affecting Leydig cell development in rats. METHODS: Thirty 35-day-old male Sprague-Dawley rats were randomly allocated to five groups mg/kg bw per day that were gavaged for 21 days with BBOP at 0, 10, 100, 250, or 500 mg/kg bw per day. The hormone profiles; Leydig cell morphological metrics; mRNA and protein levels; oxidative stress; and AKT, mTOR, ERK1/2, and GSK3β pathways were assessed. RESULTS: BBOP at 250 and/or 500 mg/kg bw per day decreased serum testosterone, luteinizing hormone, and follicle-stimulating hormone levels mg/kg bw per day (P < 0.05). BBOP at 500 mg/kg bw per day decreased Leydig cell number mg/kg bw per day and downregulated Cyp11a1, Insl3, Hsd11b1, and Dhh in the testes, and Lhb and Fshb mRNAs in the pituitary gland (P < 0.05). The malondialdehyde content in the testis significantly increased, while Sod1 and Sod2 mRNAs were markedly down-regulated, by BBOP treatment at 250-500 mg/kg bw per day (P < 0.05). Furthermore, BBOP at 500 mg/kg bw per day decreased AKT1/AKT2, mTOR, and ERK1/2 phosphorylation, and GSK3β and SIRT1 levels mg/kg bw per day (P < 0.05). Finally, BBOP at 100 or 500 μmol/L induced ROS and apoptosis in Leydig cells after 24 h of treatment in vitro (P < 0.05). CONCLUSION: BBOP delays puberty onset by increasing oxidative stress and apoptosis in Leydig cells in rats. UNLABELLED The graphical abstract is available on the website www.besjournal.com.
Rats ; Male ; Animals ; Leydig Cells/metabolism* ; Testosterone ; Glycogen Synthase Kinase 3 beta/pharmacology* ; Rats, Sprague-Dawley ; Sexual Maturation ; Testis ; Oxidative Stress ; TOR Serine-Threonine Kinases/metabolism* ; Apoptosis

The present study observed the regulatory effect of total flavonoids of Ziziphora clinopodioides on autophagy and the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin(mTOR) signaling pathways in ApoE~(-/-) mice and explored the mechanism of total flavonoids of Z. clinopodioides against atherosclerosis(AS). ApoE~(-/-) mice were fed on a high-fat diet for eight weeks to induce an AS model. The model mice were randomly divided into a model group, a positive control group, and low-, medium-and high-dose groups of total flavonoids of Z. clinopodioides, while C57BL/6J mice fed on a common diet were assigned to the blank group. The serum and aorta samples were collected after intragastric administration for 12 weeks, and the serum levels of total cholesterol(TC), triglyceride(TG), low density lipoprotein-cholesterol(LDL-C), and high density lipoprotein-cholesterol(HDL-C) were detected by an automatic biochemical analyzer. The serum expression levels of intercellular adhesion molecule-1(ICAM-1), vascular cell adhesion molecule-1(VCAM-1), matrix metalloproteinase-2(MMP-2), and matrix metalloprotei-nase-9(MMP-9) were detected by enzyme-linked immunosorbent assay(ELISA). Oil red O staining was used to observe the aortic plaque area in mice. Hematoxylin-eosin(HE) staining was used to observe the aortic plaque and pathological changes in mice. The expression of P62 and LC3 in the aorta was detected by the immunofluorescence method. The protein expression of LC3Ⅱ/Ⅰ, Beclin-1, P62, p-PI3K, p-Akt, and p-mTOR in the aorta of mice was detected by Western blot. The results showed that compared with the blank group, the serum levels of TC, TG, LDL-C, ICAM-1, VCAM-1, MMP-2 and MMP-9 in the model group were significantly increased(P<0.01 or P<0.05), the content of HDL-C was decreased(P<0.05), intra-aortic plaque area was enlarged(P<0.01), the expression of LC3 in the aorta was significantly down-regulated, P62 expression was up-regulated(P<0.01 or P<0.05), the expressions of LC3Ⅱ/Ⅰ and Beclin-1 in the aortic lysate were significantly down-regulated, and the expressions of p-PI3K, p-Akt, p-mTOR and P62 were significantly increased(P<0.01). The medium-and high-dose groups of total flavonoids of Z. clinopodioides could reduce the serum levels of TC, TG, LDL-C, ICAM-1, VCAM-1, MMP-2, and MMP-9 in AS model mice(P<0.01 or P<0.05), and increase the content of HDL-C(P<0.01 or P<0.05). The aortic plaque area of mice after middle and high doses of total flavonoids of Z. clinopodioides was significantly reduced(P<0.01), the content of foam cells decrease, and the narrowing of the lumen decreased. The total flavonoids of Z. clinopodioides significantly increased the expression of LC3 in the aorta and the expression of LC3Ⅱ/Ⅰ and Beclin-1 in the lysate, and decreased the expression of P62 in the aorta and the expression of p-PI3K, p-Akt, p-mTOR and P62 in the lysate(P<0.01 or P<0.05). The results showed that the total flavonoids of Z. clinopodioides could improve the content of blood lipids and inflammatory factors, and reduce the generation of foam cells and plaques in aortic tissue, and the mechanism may be related to the regulation of PI3K/Akt/mTOR signaling pathway.
Animals ; Mice ; Apolipoproteins E ; Atherosclerosis/genetics* ; Beclin-1 ; Cholesterol, LDL ; Intercellular Adhesion Molecule-1 ; Matrix Metalloproteinase 2/genetics* ; Matrix Metalloproteinase 9/genetics* ; Mice, Inbred C57BL ; Phosphatidylinositol 3-Kinases/metabolism* ; Plaque, Atherosclerotic ; Proto-Oncogene Proteins c-akt/metabolism* ; TOR Serine-Threonine Kinases/genetics* ; Vascular Cell Adhesion Molecule-1/genetics*

In recent years, the clinical treatment of colorectal cancer(CRC) has made great progress, but chemoresistance is still one of the main reasons for reducing the survival rate of patients with colorectal cancer. Therefore, ameliorating chemotherapy resis-tance is an urgent problem to be solved. The purpose of this study was to investigate the regulatory role and related molecular mechanisms of hydroxysafflor yellow A(HSYA) in colorectal cancer cell proliferation, migration, and 5-fluorouracil(5-FU) chemoresistance. In this study, HCT116 and HT-29 cells were used as research subjects. Firstly, methyl thiazolyl tetrazolium(MTT) assay and colony formation assay were used to detect and analyze the effect of HSYA on the proliferation of CRC cells. Secondly, the effect of HSYA on the cell cycle in CRC cells was analyzed by cell cycle assay. Furthermore, the effect of HSYA on the migration of CRC cells was analyzed by wound-healing assay and Transwell assay. Based on the above, the influences of HSYA on 5-FU chemoresistance of CRC cells and related molecular mechanisms were explored and analyzed. The results showed that HSYA significantly inhibited the proliferation and migration of CRC cells, and arrested the cell cycle in G_0/G_1 phase. In addition, HSYA significantly ameliorated the chemoresistance of CRC cells to 5-FU. The results of acridine orange staining and Western blot showed that the autophagy activity of CRC cells in the HSYA and 5-FU combined treatment group was significantly higher than that in the 5-FU single drug treatment group. As compared with the 5-FU single drug treatment group, the phosphorylation levels of protein kinase B(Akt) and mammalian target of rapamycin(mTOR) in the HSYA and 5-FU combined treatment group were significantly reduced, indicating that the Akt/mTOR signaling pathway in the combined treatment group was down-regulated in CRC cells. In conclusion, HSYA may upregulate autophagy activity through the Akt/mTOR signaling pathway, thereby inhibiting the proliferation and migration of CRC cells and ameliorating the chemoresistance to 5-FU.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Drug Resistance, Neoplasm ; Cell Line, Tumor ; TOR Serine-Threonine Kinases/metabolism* ; Fluorouracil/pharmacology* ; Cell Proliferation ; Autophagy ; Colorectal Neoplasms/drug therapy*