A family of transcription factors known as Id proteins, or inhibitor of DNA binding and differentiation, is capable of regulating cell proliferation, survival and differentiation, and is often upregulated in multiple types of tumors. Due to their ability to promote self-renewal, Id proteins have been considered as oncogenes, and potential therapeutic targets in cancer models. On the contrary, certain Id proteins are reported to act as tumor suppressors in the development of Burkitt's lymphoma in humans, and hepatosplenic and innate-like T cell lymphomas in mice. The contexts and mechanisms by which Id proteins can serve in such contradictory roles to determine tumor outcomes are still not well understood. In this review, we explore the roles of Id proteins in lymphocyte development and tumorigenesis, particularly with respect to inhibition of their canonical DNA binding partners known as E proteins. Transcriptional regulation by E proteins, and their antagonism by Id proteins, act as gatekeepers to ensure appropriate lymphocyte development at key checkpoints. We re-examine the derailment of these regulatory mechanisms in lymphocytes that facilitate tumor development. These mechanistic insights can allow better appreciation of the context-dependent roles of Id proteins in cancers and improve considerations for therapy.
Carcinogenesis ; metabolism ; Cell Physiological Phenomena ; Inhibitor of Differentiation Protein 1 ; metabolism ; Lymphocytes ; physiology ; Transcription Factors ; Tumor Suppressor Proteins ; metabolism

Research on innate lymphoid cells (ILC) has recently been a fast paced topic of immunological research. As ILCs are able to produce signature Th cytokine, ILCs have garnered considerable attention and have been described to represent the innate counterpart of the CD4 T helper (Th) cells. The development and function of ILCs are precisely regulated by a network of crucial transcription factors, which are also involved in the development or differentiation of conventional natural killer (cNK) cells and T cells. In this review, we will summarize the key transcriptional regulators and their functions through each phases of ILC development. With the phase of ILC lineage commitment, we will focus in particular on the roles of the transcription regulators Id2 and GATA-3, which in collaboration with other transcriptional factors, are critically involved in the generation of ILC fate determined progenitors. Once an ILC lineage has been established, several other transcription factors are required for the specification and functional regulation of distinct mature ILC subsets. Thus, a comprehensive understanding of the interactions and regulatory mechanisms mediated by these transcription factors will help us to further understand how ILCs exert their helper-like functions and bridge the innate and adaptive immunity.
Animals ; GATA3 Transcription Factor ; immunology ; Humans ; Immunity, Innate ; physiology ; Inhibitor of Differentiation Protein 2 ; immunology ; Killer Cells, Natural ; immunology ; T-Lymphocytes, Helper-Inducer ; immunology

OBJECTIVETo study the effects of LIF combined with bFGF on the proliferation, stemness and senescence of hUC-MSC.

METHODSExperiments were divided into 4 groups: control group, in which the cells were treated with complete medium (α-MEM containing 10% FBS); group LIF, in which the cells were treated with complete medium containing 10 ng/ml LIF; group bFGF, in which the cells were treated with complete medium containing 10 ng/ml bFGF; combination group, in which the cells were treated with complete medium containing 10 ng/ml LIF and 10 ng/ml bFGF. The growth curves of hUC-MSC at passage 4 in different groups were assayed by cell counting kit 8. Cellular morphologic changes were observed under inverted phase contrast microscope; hUC-MSC senescence in different groups was detected by β-galactosidase staining. The expression of PCNA, P16, P21, P53, OCT4 and NANOG genes was detected by RT-PCR.

RESULTSThe cell growth curves of each group were similar to the S-shape; the cell proliferation rate from high to low as follows: that in the combination group > group bFGF > group LIF > control group. Senescence and declining of proliferation were observed at hUC-MSC very early in control group; the cells in group LIF maintained good cellular morphology at early stage, but cell proliferation was slow and late senescence was observed; a few cells in group bFGF presented signs of senescence, but with quick proliferation; the cells in combination group grew quickly and maintained cellular morphology of hUC-MSC for long time. The LIF and bFGF up-regulated the expression of PCNA, OCT4 and NANOG, while they down-regulated the expression of P16, P21, P53, and their combinative effects were more significant.

CONCLUSIONLIF combined with bFGF not only can promote the proliferation and maintenance of stemness of hUC-MSC, but also can delay the senescence of hUC-MSC.

Cell Cycle ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Fibroblast Growth Factor 2 ; pharmacology ; Genes, Homeobox ; Humans ; Leukemia Inhibitory Factor ; pharmacology ; Mesenchymal Stromal Cells ; cytology ; drug effects ; Octamer Transcription Factor-3 ; metabolism ; Organic Chemicals ; Proliferating Cell Nuclear Antigen ; metabolism ; Tumor Suppressor Protein p53 ; metabolism ; Umbilical Cord ; cytology

OBJECTIVETo investigate the changes of ID1 expression in tumor cells treated with etoposide, cisplatin and ultraviolet (UV) irradiation, and explore the effect of ID1 on chemotherapeutic drug- and UV-induced apoptosis.

METHODSIn the present study, upon onset of apoptosis induced by various kinds of inducers such as etoposide, cisplatin and UV irradiation, the expression level of ID1 was detected by Western blot and real-time PCR. We also analyzed the half-life of ID1 protein and stability of ID1 mRNA respectively by cycloheximide inhibition test and RT-PCR. Annexin-V assay was carried out to evaluate the contribution of ID1 protein to chemotherapeutic drug- and UV-induced apoptosis.

RESULTSID1 expression presented a profound down-regulation in the HCT116 cells treated with etoposide, cisplatin and UV irradiation(P<0.05 for all). The apoptosis in the UV irradiation group, cisplatin group, etoposide group was (58.70±1.55)%, (35.80±0.92)% and (21.00±0.72)%, respectively, significantly higher than that of the control group(1.10±0.07)%, (1.20±0.13)% and (3.50±0.23)% (P<0.05 for all). Upon etoposide treatment, ID1 expression level was decreased via induction of mRNA instability, but not the protein degradation changes. Additionally, ectopic expression of ID1 in the HCT116 cells alleviated etoposide-, cisplatin- and UV-induced apoptosis. The results of flow eytometry revealed that the percentage of apoptotic cells in the ID1 group under the treatment of etoposide, cisplatin and UV irradiation was (23.80±0.82)%, (17.80±1.34)% and (13.40±0.53)%, respectively, significantly lower than that in the empty vector group (41.10±1.61)%, (30.40±2.67)% and (22.50±3.47)% (P<0.05 for all).

CONCLUSIONSThese observations indicate that the treatment with etoposide reduces the amount of ID1 by induction of mRNA instability, and exogenously introduced ID1 protects cells against etoposide-, cisplatin- and UV irradiation-induced apoptosis. Inhibition of the ID1 bioactivity may become a new strategy in cancer treatment.

Antineoplastic Agents ; pharmacology ; Apoptosis ; Cisplatin ; pharmacology ; Down-Regulation ; Etoposide ; pharmacology ; HCT116 Cells ; drug effects ; metabolism ; radiation effects ; Half-Life ; Humans ; Inhibitor of Differentiation Protein 1 ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Real-Time Polymerase Chain Reaction ; Ultraviolet Rays

OBJECTIVETo analyze changes in gene amplification in the mitochondrial genome and in the ID4 gene promoter methylation region in patients with chronic aplastic anemia (CAA) suffering from Kidney (Shen) yin deficiency or Kidney yang deficiency.

METHODSBone marrow and oral epithelium samples were collected from CAA patients with Kidney yin deficiency or Kidney yang deficiency (20 cases). Bone marrow samples were collected from 20 healthy volunteers. The mitochondrial genome was amplified by polymerase chain reaction (PCR), and PCR products were used for sequencing and analysis.

RESULTSHigher mutational rates were observed in the ND1-2, ND4-6, and CYTB genes in CAA patients suffering from Kidney yin deficiency. Moreover, the ID4 gene was unmethylated in bone marrow samples from healthy individuals, but was methylated in some CAA patients suffering from Kidney yin deficiency (positive rate, 60%) and Kidney yang deficiency (positive rate, 55%).

CONCLUSIONSThese data supported that gene mutations can alter the expression of respiratory chain enzyme complexes in CAA patients, resulting in energy metabolism impairment and promoting the physiological and pathological processes of hematopoietic failure. Functional impairment of the mitochondrial respiration chain induced by gene mutation may be an important reason for hematopoietic failure in patients with CAA. This change is closely related to maternal inheritance and Kidney yin deficiency. Finally, these data supported the assertion that it is easy to treat disease in patients suffering from yang deficiency and difficult to treat disease in patients suffering from yin deficiency.

Adult ; Anemia, Aplastic ; genetics ; Base Sequence ; Biopsy ; Bone Marrow ; pathology ; Case-Control Studies ; Child ; Chronic Disease ; DNA Methylation ; genetics ; DNA, Mitochondrial ; genetics ; Electrophoresis, Agar Gel ; Female ; Genome, Mitochondrial ; genetics ; Humans ; Inhibitor of Differentiation Proteins ; genetics ; Kidney ; pathology ; Male ; Middle Aged ; Mutation ; genetics ; Polymorphism, Genetic ; Promoter Regions, Genetic ; genetics ; Yin Deficiency ; genetics ; Young Adult

Objective To explore the expressions of inhibitors of DNA binding-1 (Id-1) and matrix metalloproteinase-9 (MMP-9) in colorectal carcinoma tissues and its correlation with microvessel density (MVD). Methods The expressions of Id-1 and MMP-9 as well as CD34-labelled MVD in colorectal adenocarcinoma tissues (n=50) and normal adjacent tissues (n=50) were examined by immunohistochemistry. Results The positive expressions of Id-1 and MMP-9 were seen in 72.00% (36/50) and 78.00%(39/50) of colorectal adenocarcinoma tissues,which were significantly higher than those [24.00%(12/50) and 28.00% (14/50)] in normal adjacent tissues (P=0.000). The MVD value (17.22±2.08) in colorectal adenocarcinoma tissues was significantly higher than that (5.36±2.17) in normal adjacent tissues (P=0.000). The expressions of Id-1 and MMP-9 and MVD were significantly correlated with serosa invasion,TNM stage,carcinoembryonic antigen(+),lymph node metastasis,vascular invasion,and liver metastasis (all P<0.05) but not with the patient's age,gender,tumor size,and differentiation degree (all P>0.05). The MVD value with Id-1 and MMP-9 positive expression were significantly higher than those with Id-1 and MMP-9 negative expression (all P=0.000). The expression of Id-1 in colorectal adenocarcinoma tissues showed significantly positive correlation with that of MMP-9 (r=0.429,P=0.000). Cox multivariate analysis showed that Id-1 and MMP-9 expressions were independent prognostic factors for colorectal carcinoma. Conclusions The high expressions of Id-1 and MMP-9 have high correlations with the development and progression of colorectal adenocarcinoma and have positive correlation with MVD. Both of them may be involved in the microvascular generation and the invasion and hematogenous metastasis of colorectal carcinoma.
Adenocarcinoma ; blood supply ; metabolism ; Colorectal Neoplasms ; blood supply ; metabolism ; Disease Progression ; Humans ; Immunohistochemistry ; Inhibitor of Differentiation Protein 1 ; metabolism ; Liver Neoplasms ; Lymphatic Metastasis ; Matrix Metalloproteinase 9 ; metabolism ; Microcirculation ; Microvessels ; Neovascularization, Pathologic

OBJECTIVETo evaluate significance of ID4 gene mehtylation in demethylating myelodysplastic syndrome(MDS) cell Line MUTZ1 and 2 patients with MDS.

METHODSThe methylation-specific PCR (MS-PCR) and reverse transcription-PCR (RT-PCR) were applied to identify the methylation status and gene expression of ID4 gene in MDS cell line MUTZ1, a patient with aplastic anemia(AA) and a donor with normal bone marrow (NBM). RT-PCR was applied to detect the ID4 gene expression status in MUTZ1 cell line treated with decitabine at 3 different concentrations. Then bisulfite sequencing PCR (BSP) was applied to detect ID4 gene methylation status in 2 MDS parients treated with decitabine.

RESULTSThe MDS cell line MUTZ-1 displayed a complete methylation of ID4 gene promoter with little mRNA expression. Inversely, bone marrow of an AA patient and NBM showed complete unmethylation of this gene with intensity mRNA expression. With the increase of decitabine concentration, ID4 gene mRNA expression was more and more increased. After decitabine treatment, ID4 gene methylation-positive frequencies of both the 2 MDS patients were much more decreased than that of the first treatment. So, ID4 gene mRNA expression inhibited by promoter hypemethylation could be recovered by using demethylation medicine.

CONCLUSIONID4 as a new potential anti-oncogene suggests that its methylation may become a marker for selection and assessment of therapeutic schedules in patients with MDS.

Anemia, Aplastic ; Azacitidine ; analogs & derivatives ; Bone Marrow ; Cell Line ; DNA Methylation ; Gene Expression ; Genes, Tumor Suppressor ; Humans ; Inhibitor of Differentiation Proteins ; Myelodysplastic Syndromes ; Polymerase Chain Reaction ; Promoter Regions, Genetic

BACKGROUNDThe diagnosis of myelodysplastic syndrome (MDS), especially hypoplastic MDS, and MDS with low blast counts or normal karyotype may be problematic. This study characterized ID4 gene methylation in patients with MDS and aplastic anemia (AA).

METHODSThe methylation status of ID4 was analyzed by bisulfite sequencing polymerase chain reaction (PCR) and quantitative real-time methylation-specific PCR (MethyLight PCR) in 100 patients with MDS and 31 patients with AA.

RESULTSThe MDS group had a higher ID4 gene methylation positivity rate (22.22%) and higher methylation levels (0.21 [0-3.79]) than the AA group (P < 0.05). Furthermore, there were significant differences between the hypoplastic MDS and AA groups, the MDS with low blast count and the AA groups, and the MDS with normal karyotype and the AA groups. The combination of genetic and epigenetic markers was used in much more patients with MDS (62.5% [35/56]) than the use of genetic markers only (51.79% [29/56]).

CONCLUSIONSThese results showed that the detection of ID4 methylation positivity rates and levels could be a useful biomarker for MDS diagnosis.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Anemia, Aplastic ; genetics ; Child ; CpG Islands ; genetics ; DNA Methylation ; genetics ; Female ; Humans ; Inhibitor of Differentiation Proteins ; genetics ; Male ; Middle Aged ; Myelodysplastic Syndromes ; genetics ; Young Adult

Adult ; Aged ; Arsenicals ; pharmacology ; therapeutic use ; Bone Marrow Cells ; drug effects ; metabolism ; DNA Methylation ; drug effects ; Female ; Humans ; Inhibitor of Differentiation Proteins ; metabolism ; Male ; Middle Aged ; Myelodysplastic Syndromes ; metabolism ; therapy ; Oxides ; pharmacology ; therapeutic use ; Treatment Outcome ; Young Adult

OBJECTIVETo investigate the mechanisms by which retinoic acid-induced gene G (RIG-G) protein regulates p21 gene expression.

METHODSWestern blot was used to detect the effects of RIG-G protein overexpression on p21 protein expression level in leukemia cell line NB4 cells and the phosphorylation of both c-Jun and JNK in U937 cells. The c-Jun expression plasmid and p21 gene promoter-containing reporter plasmid were co-transfected into 293T cells, to explore the regulatory effect of c-Jun protein on p21 gene expression by luciferase reporter assay.

RESULTSWestern blot showed that the overexpression of RIG-G protein significantly upregulated p21 protein level in the NB4 cells, and the level of p21 protein largely increased along with the induction of endogenous RIG-G protein during the differentiation of NB4 cells treated by all-trans retinoic acid (ATRA). Moreover, the phosphorylation of both c-Jun and JNK decreased in RIG-G-overexpressing U937 cells while total c-Jun and JNK proteins remained unchanged. After using the JNK inhibitor SP600125 to block JNK phosphorylation, the level of c-Jun phosphorylation was still dramatically reduced in the RIG-G-overexpressing U937T-RIG-G cells, compared with the control U937T-pTRE cells. These results indicated that the inhibitory effect of Rig-G protein on c-Jun phosphorylation could not only be through the JNK pathway, but also via some JNK-independent pathways. Luciferase reporter assay showed that when 0.1, 0.5, 1.0 and 2.0 µg c-Jun-expressing plasmids were respectively transfected into 293T cells, compared with the empty vector-transfected group, the relative luciferase activities were (83.0 ± 1.7)%, (73.7 ± 0.7)%, (68.9 ± 0.9)% and (64.1 ± 0.9)%, indicating that the transcriptional activity of p21 gene could be inhibited by c-Jun protein.

CONCLUSIONSRIG-G protein may suppress the phosphorylation of c-Jun protein through different signal pathways, thereby increasing the expression of p21 gene, arresting the cell cycle and inhibiting the cell growth in U937 cells.

Cell Cycle ; Cell Differentiation ; Cell Line ; Cell Proliferation ; Cyclin-Dependent Kinase Inhibitor p21 ; genetics ; metabolism ; GTP-Binding Proteins ; genetics ; metabolism ; Genes, Reporter ; Phosphorylation ; Signal Transduction ; Transfection ; Tretinoin ; metabolism ; Up-Regulation