OBJECTIVE: To investigate the effect of U2AF1 gene mutation to inflammatory cytokine in SKM-1 cell of human myelodysplastic syndromes (MDS), and whether the above effects were mediated by FOXO3a-Bim signaling pathway. METHODS: Wide-type U2AF1 and mutant U2AF1 (the serine residue 34 was replaced by phenylalanine, and named as S34F) recombinant expression plasmids were constructed. Lentiviruses were packaged and transfected into SKM-1 cells. The expression of FOXO3a was up-regulated by lentiviruses, and its transfection rate was investigated. The cell proliferation was detected by CCK-8 method. Flow cytometry was used to detect the apoptosis and cycle of the cells. The expression pro-inflammatory cytokine IL-1β, IL-6, TNF-α and anti-inflammatory cytokine IL-4 were detected by qRT-PCR. FOXO3a, Bim, Bcl-2 and Bax protein expression levels were detected by Western blot. RESULTS: Compared with the control group, the cell apoptosis rate, pro-inflammatory cytokine IL-1β and TNF-α transcription levels were significantly increased in the S34F group (P<0.05); cell cycle was blocked at the G CONCLUSION U2AF1 S34F mutation can regulate inflammatory phenotype in SKM-1 cells, which may be mediated through FOXO3a-Bim signaling pathway.
Cytokines ; Forkhead Box Protein O3/metabolism* ; Humans ; Mutation ; Signal Transduction ; Splicing Factor U2AF

Age-dependent loss of skeletal muscle mass and function is a feature of sarcopenia, and increases the risk of many aging-related metabolic diseases. Here, we report phenotypic and single-nucleus transcriptomic analyses of non-human primate skeletal muscle aging. A higher transcriptional fluctuation was observed in myonuclei relative to other interstitial cell types, indicating a higher susceptibility of skeletal muscle fiber to aging. We found a downregulation of FOXO3 in aged primate skeletal muscle, and identified FOXO3 as a hub transcription factor maintaining skeletal muscle homeostasis. Through the establishment of a complementary experimental pipeline based on a human pluripotent stem cell-derived myotube model, we revealed that silence of FOXO3 accelerates human myotube senescence, whereas genetic activation of endogenous FOXO3 alleviates human myotube aging. Altogether, based on a combination of monkey skeletal muscle and human myotube aging research models, we unraveled the pivotal role of the FOXO3 in safeguarding primate skeletal muscle from aging, providing a comprehensive resource for the development of clinical diagnosis and targeted therapeutic interventions against human skeletal muscle aging and the onset of sarcopenia along with aging-related disorders.
Animals ; Humans ; Sarcopenia/metabolism* ; Forkhead Box Protein O3/metabolism* ; Muscle, Skeletal/metabolism* ; Aging/metabolism* ; Primates/metabolism*

OBJECTIVE: To investigate the drug resistant related FOXO3/Bcl-6 signaling pathway in K562/G cell line and its related microRNA(miRNA) mechanisms. METHODS: The drug resistance potency of imatinib on K562/G was detected by MTT assay. The expression of FOXO3 and Bcl-6 proteins in K562 and K562/G cells was detected by Western blot. Real-time PCR (RT-PCR) was used to detect the expression of FOXO3 and Bcl-6 mRNA. The miRNA expression profiling in K562 and K562/G cells was analyzed by microarray technique, and the miRNA targeted to FOXO/Bcl-6 signaling pathway was identified. RESULTS: The expression of FOXO3 and Bcl-6 protein was significantly increased in K562/G cells as compared with that in K562 cells (P<0.01), the expression level of Bcl-6 mRNA showed no increase in K562/G cells. However, FOXO3 mRNA was up-regulated in K562/G cells (P<0.05). MiRNA microarray results showed that 109 miRNAs were expressed differentially in K562 and K562/G cells. The expression of 81 miRNAs were up-regulated while 28 miRNAs were down-regulated. Through reverse prediction by bioinformatics, miR-6718-5p, miR-5195-5p, miR-4711-3p, miR-4763-5p, miR-4664-5p and miR-3176 were related to FOXO/Bcl-6 signaling pathway. CONCLUSION The FOXO3/Bcl-6 signaling pathway contributes to imatinib resistance in K562/G cell line, and the miRNA expression profiles showed significant differences between K562/G and K562 cells.
Forkhead Box Protein O3/genetics* ; Humans ; Imatinib Mesylate/pharmacology* ; K562 Cells ; MicroRNAs/genetics* ; RNA, Messenger ; Signal Transduction

To study the effect of Huangqin Qingre Chubi Capsules containing serum on the protein expressions of AMPK and FoxO3 a in peripheral blood mononuclear cells of patients with rheumatoid arthritis(RA), in order to explore the mechanism of anti-oxidation. Peripheral anticoagulant was collected from patients and normal people. Monocytes(PBMC) were isolated through density gradient centrifugation, and the logarithmic phase cells were cultured. Drug containing serum was prepared through intragastric admini-stration to SD rats. The rats were divided into five groups, namely normal group, model group, AMPK blocker group(compound C 10 μmol·L~(-1)), medium-dose HQC+AMPK blocker group, and middle-dose HQC group. The cell inhibition rate was calculated by MTT method. The levels of IL-1β, IL-4, LPO, MDA, SOD and TAOC were detected by ELISA. The expressions of AMPK, p-AMPK, p-FoxO3 a and FoxO3 a were detected by Western blot. The HQC containing serum had an inhibitory effect on human monocytes in peripheral blood. The best concentration was observed in middle-dose HQC, and the best time was 24 hours. Middle-dose HQC group was better than model group, AMPK blocker group and middle-dose HQC + AMPK blocker group in terms of increase of SOD, p-AMPK, p-FoxO3 a and decrease of LPO. It was better than model group and AMPK blocker group in terms of increase of IL-4, TAOC, AMPK, FoxO3 a and decrease of IL-1β, MDA. The differences were statistically significant(P<0.05 or P<0.01). The HQC containing serum may increase the levels of TAOC and SOD, decrease the level of MDA and LPO, activate AMPK, directly phosphorylate FOXO3 a, enhance its transcriptional activity, and improve the state of oxidative stress in RA patients.
AMP-Activated Protein Kinases ; Animals ; Arthritis, Rheumatoid ; Capsules ; Forkhead Box Protein O3 ; Humans ; Leukocytes, Mononuclear ; Oxidative Stress ; Rats ; Rats, Sprague-Dawley ; Scutellaria baicalensis

The forkhead family members of transcription factors (FoxOs) are expected to be potential cancer-related drug targets and thus are being extremely studied recently. In the present study, FoxO3a, one major member of this family, was identified to be down-regulated in colorectal cancer through micro-array analysis, which was confirmed by RT-PCR and Western blot in 28 patients. Moreover, immunohistochemistry (IHC) showed that the expression levels of FoxO3a were remarkably reduced in 99 cases of primary colorectal cancer, liver metastasis, and even in metaplastic colorectal tissue. IHC also revealed an exclusion of FoxO3a from the nucleus of most cells of tumor-associated tissues. Silencing FoxO3a by siRNA led to elevation of G2-M phase cells. We conclude that the downregulation of FoxO3a may greatly contribute to tumor development, and thus FoxO3a may represent a novel therapeutic target in colorectal cancer.
Cell Cycle Checkpoints ; Colon ; metabolism ; pathology ; Colorectal Neoplasms ; metabolism ; pathology ; Down-Regulation ; Female ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; metabolism ; Humans ; Liver Neoplasms ; metabolism ; pathology ; secondary ; Male ; Metaplasia ; metabolism ; pathology ; Rectum ; metabolism ; pathology ; Tumor Cells, Cultured

This study was aimed to investigate the expression and clinical significance of forkhead box protein O3a (FoxO3a) in the patients with acute myeloid leukemia (AML). Western blot was used to detect the FoxO3a protein expression in bone marrow samples from 44 newly diagnosed AML patients and 5 healthy donors. Additionally, 14 patients' samples were reevaluated when they got complete remission (CR). The results showed that FoxO3a expression (FoxO3a/β-actin 0.43 ± 0.19) in newly diagnosed AML patients was much higher than that in healthy donors (FoxO3a/β-actin 0.19 ± 0.06) (P < 0.001). The FoxO3a level was down-regulated when CR was got and there was not significant difference between patients in CR and healthy donors (P > 0.10). The correlation analysis showed that the level of FoxO3a expression positively correlated with the white blood cell count of AML patients at the time of diagnosis. Although FoxO3a expression did not positively correlate with the CR rate, the higher FoxO3a expression in AML patients showed a shorter remission duration. It is concluded that FoxO3a may be a oncoprotein in AML, and the high FoxO3a expression is associated with poor prognosis.
Adolescent ; Adult ; Aged ; Bone Marrow Cells ; metabolism ; Case-Control Studies ; Child ; Female ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; metabolism ; Humans ; Leukemia, Myeloid, Acute ; diagnosis ; metabolism ; Male ; Middle Aged ; Oncogene Proteins ; metabolism ; Prognosis ; Remission Induction ; Young Adult

Targeted therapies include small-molecule inhibitors and monoclonal antibodies, have made treatment more tumor-specific and less toxic, and have opened new possibilities for tailoring cancer treatment. Nevertheless, there remain several challenges to targeted therapies, including molecular identification, drug resistance, and exploring reliable biomarkers. Here, we present several selected signaling pathways and molecular targets involved in human cancers including Aurora kinases, PI3K/mTOR signaling, FOXO-FOXM1 axis, and MDM2/MDM4-p53 interaction. Understanding the molecular mechanisms for tumorigenesis and development of drug resistance will provide new insights into drug discovery and design of therapeutic strategies for targeted therapies.
Aurora Kinases ; metabolism ; Drug Resistance, Neoplasm ; Forkhead Box Protein M1 ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; metabolism ; Humans ; Molecular Targeted Therapy ; Neoplasms ; metabolism ; therapy ; Nuclear Proteins ; metabolism ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins ; metabolism ; Proto-Oncogene Proteins c-mdm2 ; metabolism ; Signal Transduction ; TOR Serine-Threonine Kinases ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVETo explore the effects of EGFR-TKI AG1478 on the expression of FoxMl and FOXO3a genes in non-small cell cancer (NSCLC) cell lines, and explore the effect on cell proliferation and drug sensitivity to AG1478 after down-regulation of FOXMl and FOXO3a expression by RNAi technique.

METHODSHuman lung cancer cells were treated with AG1478 at different concentrations. RT-PCR and Western blot were used to examine the expression of P-EGFR, FOXM1, FOXO3a mRNA and protein. After transient transfection of FOXM1 and FOXO3a siRNA, RT-PCR and Western blot were employed to determine the transfection efficiency and expression of the related proteins. CCK-8 assay, colony formation assay and flow cytometry were performed to evaluate the cell proliferation, colony formation ability and the changes in cell cycle distribution.

RESULTSThe expressions of FOXM1 mRNA and protein were inhibited by AG1478 in a dose-dependent manner (both P < 0.05). After transfection with FOXM1 siRNA, the expressions of FOXM1 mRNA and protein, and proteins of cyclin B1, c-Myc, and Bcl-2 were significantly down-regulated, and the expressions of p21 and cleaved-PARP proteins were significantly up-regulated (all P < 0.05). The colony number of FOXM1siRNA transfection group was 37.3 ± 8.6, significantly lower than that of the blank control (135.3 ± 7.0) and negative control group (125.3 ± 7.5, P < 0.05). The colony formation inhibition rate was (7.40 ± 0.94)% in the negative control group and (72.4 ± 6.09)% in the FOXM1 siRNA transfection group. FOXM1siRNA transfection induced cell cycle arrest at G2/M phase with a percentage of (55.6 ± 4.83)%, significantly higher than that of the blank control [(24.30 ± 1.95)%] and negative control group [(21.3 ± 2.06)%, P < 0.05]. Additionally, the FOXM1siRNA transfection significantly increased the chemosensitivity of A549 cells to AG1478 (P < 0.05). Besides, AG1478 induced expression and nuclear relocation of FOXO3a. After the FOXO3a siRNA transfection, the expression of FOXM1 protein was significantly up-regulated, and resulted in a reduction of AG1478-induced inhibition of FOXM1.

CONCLUSIONSThe expression of FOXM1 is down-regulated by AG1478 via FOXO3a in the NSCLC cell lines, and then increases the chemosensitivity of A549 cells to AG1478. It suggests that FOXM1 could be a potential target for the therapy and drug exploitation for NSCLC.

Adenocarcinoma ; metabolism ; pathology ; Apoptosis ; Cell Cycle ; Cell Line, Tumor ; Cell Proliferation ; Dose-Response Relationship, Drug ; Down-Regulation ; Forkhead Box Protein M1 ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; genetics ; metabolism ; Humans ; Lung Neoplasms ; metabolism ; pathology ; Quinazolines ; administration & dosage ; pharmacology ; RNA, Messenger ; metabolism ; RNA, Small Interfering ; genetics ; Receptor, Epidermal Growth Factor ; antagonists & inhibitors ; Transfection ; Tyrphostins ; administration & dosage ; pharmacology

The FOXO3a and FOXM1 forkhead transcription factors are key players in cancer initiation, progression, and drug resistance. Recent research shows that FOXM1 is a direct transcriptional target of FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling cascade. In addition, FOXM1 and FOXO3a also antagonize each other's activity by competitively binding to the same target genes, which are involved in chemotherapeutic drug sensitivity and resistance. Understanding the role and regulation of the FOXO-FOXM1 axis will provide insight into chemotherapeutic drug action and resistance in patients, and help to identify novel therapeutic approaches as well as diagnostic and predictive biomarkers.
Antineoplastic Agents ; pharmacology ; therapeutic use ; Carcinogenesis ; genetics ; metabolism ; Drug Resistance, Neoplasm ; Forkhead Box Protein M1 ; Forkhead Box Protein O3 ; Forkhead Transcription Factors ; genetics ; metabolism ; Humans ; Neoplasms ; drug therapy ; metabolism ; pathology ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Signal Transduction

OBJECTIVETo explore the mechanisms of neuroprotective effects of c-Jun N-terminal kinase (JNK)/FOXO3a transcription factor signaling pathway inhibition on hypoxic-ischemic neuronal apoptosis in neonatal rats with hypoxic-ischemic brain damage (HIBD).

METHODSSixty-four 7-day-old Sprague-Dawley rats were divided into four groups: hypoxia-ischemia (HI), sham-operated, JNK specific inhibitor AS601245-treated, and DMSO vehicle. Rats' cerebral cortexes were collected at 24 hours after HI. Western blot was used to detect the protein expression of JNK, p-JNK, FOXO3a, nuclear and cytoplasmic FOXO3a, Bim, and CC3. TUNEL staining was used to detect the apoptotic cells.

RESULTSCompared with the sham-operated group, p-JNK protein increased (P<0.01), nuclear protein of FOXO3a increased (P<0.01), cytoplasmic protein decreased (P<0.01), and pro-apoptotic proteins Bim and CC3 increased 24 hours after HI (P<0.01). Compared with the HI and DMSO vehicle groups, p-JNK protein was reduced (P<0.01), nuclear protein of FOXO3a was also reduced (P<0.01), cytoplasmic protein increased (P<0.01), and Bim and CC3 proteins decreased (P<0.01) in the AS601245-treated group 24 hours after HI. TUNEL positive cells were reduced in the AS601245-treated rats compared with the HI and DMSO vehicle groups 24 hours after HI (P<0.01).

CONCLUSIONSJNK activity increases in the neonatal rat brain with HI damage. JNK activity inhibition can inhibit FOXO3a translocation from cytoplasm to nucleus and downregulate the levels of pro-apoptotic proteins Bim and CC3, leading to the reduction of neuronal apoptosis.

Active Transport, Cell Nucleus ; Animals ; Animals, Newborn ; Apoptosis ; Cell Nucleus ; metabolism ; Female ; Forkhead Box Protein O3 ; metabolism ; Hypoxia-Ischemia, Brain ; pathology ; JNK Mitogen-Activated Protein Kinases ; physiology ; Male ; Neurons ; pathology ; Rats ; Rats, Sprague-Dawley