Análise imuno-histoquímica da Yes-Associated Protein (YAP) e sua influência sobre a proliferação celular e a apoptose em lesões odontogênicas epiteliais benignas / Immunohistochemical analysis of Yes-Associated Protein (YAP) and its influence on cell proliferation and apoptosis in benign epithelial odontogenic lesions

Introdução: Os cistos e tumores odontogênicos são lesões que apresentam comportamento biológico heterogêneo e patogênese ainda não totalmente esclarecida. A Yes-associated protein (YAP) atua como um regulador transcricional de genes envolvidos na proliferação celular e na apoptose, participando da ativação de vias associadas ao crescimento cístico e à progressão neoplásica. Objetivo: Analisar a expressão imuno-histoquímica da proteína YAP e correlacioná-la com marcadores envolvidos na proliferação celular e na apoptose em lesões odontogênicas epiteliais benignas. Metodologia: A amostra consistiu de 95 casos de lesões odontogênicas - 25 cistos dentígeros (CDs), 30 CO não sindrômicos (COs), 30 AMB convencionais (AMB-Cs) e 10 AMB unicísticos (AMB-Us) -, além de 10 espécimes de folículo dentários (FD). Foi realizada coleta dos dados clinico-demográficos dos casos, bem como análise morfológica para melhor caracterização da amostra. Os cortes histológicos foram submetidos à técnica imuno-histoquímica através da utilização dos anticorpos YAP, ciclina D1, Ki-67 e Bcl-2, e a análise da expressão destes foi realizada quali-quantitativamente, mediante metodologia adaptada. Os dados coletados seguiram para análise descritiva e estatística (p ≤ 0,05). Resultados: Houve discreta predileção por mulheres (n = 55; 57,6%) e por indivíduos na faixa etária dos 21 aos 40 anos (n = 50; 47,6%), sendo a região posterior de mandíbula mais afetada (64%). A análise da imunoexpressão de YAP revelou maiores níveis de expressão em COs, especialmente nas camadas basal e parabasal, seguido dos AMB-Us e AMB-Cs, que demonstraram moderada imunorreatividade, predominantemente nas células periféricas. Além disso, houve diferenças significativas quanto à imunoexpressão de YAP entre os grupos analisados, com existência de correlações positivas e estatisticamente significativas entre YAP e ciclina D1 em CDs e AMB-Us, e entre YAP e Ki-67 em AMB-Us (p < 0,05). Todavia, entre a imunoexpressão YAP e Bcl-2, foi verificada ausência de correlação estatisticamente significativa. Conclusões: A YAP pode exercer influência sobre a proliferação celular do epitélio de cistos e tumores odontogênicos, auxiliando, assim, na progressão das diferentes lesões odontogênicas (AU).

Background: Odontogenic cysts and tumors present heterogeneous biological behavior, and their etiopathogenesis is not fully understood yet. Yes-associated protein (YAP) acts as a transcriptional regulator of genes involved in cell proliferation and apoptosis, activating pathways associated with cystic growth and neoplastic progression. Objective: To analyze the immunohistochemical expression of YAP protein and correlate it with markers involved in cell proliferation and apoptosis in benign epithelial odontogenic lesions. Methods: The sample consisted of 95 cases of odontogenic lesions - 25 dentigerous cysts (DCs), 30 non-syndromic odontogenic keratocyst (OKCs), 30 conventional AMB (C-AMBs), and 10 unicystic AMB (UAMBs) -, in addition to 10 specimens of dental follicles (DF). Clinicodemographic data collection was carried out, as well as morphological analysis for better characterization of the sample. The histological sections were submitted to the immunohistochemical technique using YAP, cyclin D1, Ki-67, and Bcl-2 antibodies, and their immunoexpression analysis was performed qualitatively and quantitatively, through an adapted methodology. The collected data were submitted for descriptive and statistical analysis (p ≤ 0.05). Results: There was a slight predilection for women (n = 55; 57.6%) and individuals aged between 21 and 40 years (n = 50; 47.6%), with the posterior region of the mandible as the most affected site (64%). Analysis of YAP immunoexpression revealed higher expression levels in OKCs, especially in the basal and parabasal layers, followed by U-AMBs and C-AMBs, which showed moderate immunoreactivity, predominantly in peripheral cells. In addition, there were significant differences in YAP immunoexpression between the analyzed groups, with positive and statistically significant correlations between YAP and cyclin D1 in DCs and U-AMBs, and between YAP and Ki-67 in U-AMBs (p < 0.05). However, between YAP and Bcl-2 immunoexpression, there was no statistically significant correlation. Conclusions: YAP may influence on the cell proliferation of odontogenic cysts and tumors epithelium, thus helping with the progression of the different odontogenic lesions (AU) .

Role of heteroplasmic mutations in the mitochondrial genome and the ID4 gene promoter methylation region in the pathogenesis of chronic aplastic anemia in patients suffering from Kidney yin deficiency / 中国结合医学杂志

<p><b>OBJECTIVE</b>To 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.</p><p><b>METHODS</b>Bone 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.</p><p><b>RESULTS</b>Higher 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%).</p><p><b>CONCLUSIONS</b>These 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.</p>

Quantitative Detection of ID4 Gene Aberrant Methylation in the Differentiation of Myelodysplastic Syndrome from Aplastic Anemia / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The 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).</p><p><b>METHODS</b>The 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.</p><p><b>RESULTS</b>The 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]).</p><p><b>CONCLUSIONS</b>These results showed that the detection of ID4 methylation positivity rates and levels could be a useful biomarker for MDS diagnosis.</p>

Clinical Significance of ID4 Gene Mehtylation in Demethylation-Treated MDS Cell Line and 2 MDS Patients / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To evaluate significance of ID4 gene mehtylation in demethylating myelodysplastic syndrome(MDS) cell Line MUTZ1 and 2 patients with MDS.</p><p><b>METHODS</b>The 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.</p><p><b>RESULTS</b>The 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.</p><p><b>CONCLUSION</b>ID4 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.</p>

Clinical significance of ID4 methylation detection by quantitative methylation-specific PCR in acute leukemia / 中国实验血液学杂志

The advances of treatment improved the prognosis of the patients with acute leukemia (AL) in the last decade, but the lack of general biomarker for predicting relapse in AL, which is one of the most important factors influencing the survival and prognosis. DNA methylation of ID4 gene promoter occurred frequently in patients with AL and was found to be highly related to the tumor progression. Based on the previous work of the setup of methylation-specific quantitative PCR system for ID4 gene, this study was designed to investigate the relation between the quantitative indicator of methylation density, percentage of methylation reference(PMR) value, and different disease status of AL. PMR of ID4 was detected by MS-PCR in bone marrow (BM) samples of 17 healthy persons and 54 AL patients in the status of newly diagnosis, complete remission and disease relapse. The results showed that at different disease status, PMR value in newly diagnosed group was significantly lower than that in complete remission group (P = 0.031). Among serial samples, PMR value remained very low at the status of patients with continuous complete remission (<1.5‰), and increased along with the accumulation of tumor cells at relapse. In 1 relapse case, the abnormal rise of PMR value occurred prior to morphological relapse. PMR value seemed to be related to body tumor cell load. It is concluded that the quantitative indicator of methylation density and PMR value may reflect the change of tumor cell load in acute leukemia patients. Dynamic monitoring of PMR maybe predict leukemia relapse.

Establishment of methylation-specific quantitative PCR system for ID4 gene in acute leukemia cells and its specificity and sensitivity / 中国实验血液学杂志

DNA methylation of ID4 gene promoter occurred frequently in patients with acute leukemia and was found to be highly related to the tumor progression. Due to lack of the appropriate methylation detection methods, the relation between the quantification of ID4 methylation and the states of acute leukemia is still unclear. This study purposed to set up a methylation-specific quantitative PCR system for ID4 and investigate the specificity and sensitivity of this methylation detection. The plasmids combined with target gene as well as with internal reference were constructed, and the standard curves were set up by using above mentioned plasmids. The specificity of this detection system in cell lines was verified through techniques of MSP and quantitative MSP. The sensitivity of this detection system was verified by mixing methylation-positive and negative cell lines in varying proportions and through amplification of qualitative MSP. The results showed that the standard curves were establish successfully. The results of quantitative MS-PCR in cell lines were consistent with those of MS-PCR, and as low as 1: 10(-5) of ID4 methylation positive cells could be detected by the new methylation detection assay. In newly diagnosed acute leukemia patients, the positive rate of quantitative MSP was higher. It is concluded that a complete quantitative MSP system for ID4 methylation detection has been established and this quantitative MSP method has good specificity and high sensitivity.

Expression of Id1 and Id3 in endometrial carcinoma and their roles in regulating biological behaviors of endometrial carcinoma cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the expression of inhibitor of DNA differentiation/DNA binding 1 (Id1) and Id3 in endometrial carcinoma and explore their roles in regulating the proliferation, invasion, migration and adhesion of endometrial carcinoma cells in vitro.</p><p><b>METHODS</b>Id1 and Id3 expression in 4 fresh endometrial cancer tissue specimens and matched adjacent tissues were detected using Western blotting. Two endometrial cancer cell lines, HEC-1-B and RL-952, were both divided into 4 groups, namely the untreated group, blank virus group, promoter group and Id1/Id3 double-knockdown group, and their expressions of MMP2, CXCR4 and P21 were detected by qRT-PCR and Western blotting. The proliferation, invasion, migration and adhesion of the cells were evaluated with MTT, Transwell, wound-healing, and adhesion assays.</p><p><b>RESULTS</b>Endometrial carcinoma tissues showed significantly higher Id1 and Id3 expression than the adjacent tissues (P<0.05). In the two endometrial carcinoma cell lines, Id1/Id3 double-knockdown significantly decreased MMP2 and CXCR4 expression and increased P21 expression at both mRNA and protein levels (P<0.05), and resulted in suppressed cell proliferation, invasion, migration and adhesion.</p><p><b>CONCLUSION</b>Id1 and Id3 expressions are up-regulated in endometrial carcinoma to promote the proliferation, invasion, migration and adhesion of the tumor cells by increasing MMP2 and CXCR4 expression and reducing P21 expression. Therapies targeting Id1/Id3 can be a novel strategy for treatment of endometrial carcinoma.</p>

FHL2 inhibits the Id3-promoted proliferation and invasive growth of human MCF-7 breast cancer cells / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Id3 plays a key role in the progression of breast cancer. Previously, four and a half LIM protein (FHL2) was identified as a repressor of Id family proteins by interacting with them. This study aimed to investigate the effects of FHL2 on the transcriptional regulation and oncogenic activities of Id3 in human breast cancer cells.</p><p><b>METHODS</b>Cell transfection was performed with SuperFect reagent. Stable transfectants that overexpressed Id3 were obtained by selection on G418. The level of Id3 protein was determined by Western blotting analysis. Dual luciferase assays were used to measure the effect of Id3 and FHL2 on E47-mediated transcriptional activity in MCF-7 human breast cancer cells. The MTT assay was used to measure cell proliferation. The transwell assay was used to measure the invasive capacity of MCF-7 cancer cells.</p><p><b>RESULTS</b>Id3 markedly repressed transcription mediated by the basic helix-loop-helix (bHLH) factor E47 in MCF-7 cells. This Id3-mediated repression was effectively antagonized by FHL2. Overexpression of Id3 markedly promoted the proliferation and invasive capacity of MCF-7 cells; however, these effects were significantly suppressed by the overexpression of FHL2.</p><p><b>CONCLUSIONS</b>FHL2 can inhibit the proliferation and invasive growth of human breast cancer cells by repressing the functional activity of Id3. The functional roles of FHL2-Id3 signaling in the development of human breast cancer need further research.</p>

Study on the correlation between Chinese medical syndrome types and ID4 gene promoter methylation in human acute myeloid leukemia / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To investigate the correlation between Chinese medical syndrome type (CMST) and the ID4 gene promoter methylation state in the bone marrow cells of acute myeloid leukemia (AML) patients, and to discuss the correlation between ID4 gene methylation and the occurrence, development of AML.</p><p><b>METHODS</b>Thirty-five inpatients or outpatients from the Department of Hematology, the Affiliated Hospital of Shandong University of Traditional Chinese Medicine were recruited as the test group, while 10 healthy volunteers from the health medical center of the Affiliated Hospital, Shandong University of Traditional Chinese Medicine were recruited as the control group. The ID4 gene promoter methylation states were detected using methylation specific polymerase chain reaction (MS-PCR) in the two groups. Inter-group comparison was performed and CMSTs were compared to analyze the correlation between CMSTs and the gene promoter methylation.</p><p><b>RESULTS</b>Twenty-seven AML patients (77.1%) had methylation of ID4 gene, showing statistical difference when compared with the control group (P < 0.01). The ID4 methylation positive rate of ID4 gene promoter methylation was sequenced from low to high as qi and yin deficiency syndrome < inter-accumulation of blood stasis and phlegm syndrome < toxic heat inflaming syndrome, showing statistical difference when compared with the control group (P < 0.05). The peripheral white blood cells and the bone marrow blast cells were higher in ID4 methylation positive patients than in the ID4 methylation negative control patients with statistical difference (P < 0.05).</p><p><b>CONCLUSIONS</b>Patients of inter-accumulation of blood stasis and phlegm syndrome and toxic heat inflaming syndrome were more likely to have ID4 gene methylation. The ID4 methylation positive expression has verified the essence of evil domination in the early AML at the molecular level. It can also reflect the degree of malignancy of AML to some extent.</p>

Expression of ID3 protein in prostate cancer and its clinicopathological significance / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the expression of the ID3 protein in prostate cancer and its clinicopathological significance.</p><p><b>METHODS</b>We detected the expression of the ID3 protein in PC-3M cells by indirect immunofluorescence, and that in 29 prostate cancer and 15 prostate hyperplasia specimens by immunohistochemistry. Then we analyzed the correlation between the expression level of ID3 and the clinicopathological parameters.</p><p><b>RESULTS</b>The ID3 protein was expressed predominantly in the nucleus of PC-3M cells. Its expression rate was 82.7% (24/29) in the prostate cancer specimens, significantly higher than 6.6% (1/15) in prostate hyperplasia (P < 0.05), and was positively correlated with the Gleason score of prostate cancer (P < 0.05).</p><p><b>CONCLUSION</b>The ID3 protein is expressed in prostate cancer, and is elevated with the increase of Gleason score.</p>

ID4 promoter methylation in acute myeloid leukemia / 中国实验血液学杂志

Objective of this study was to investigate the ID4 gene methylation status in patients with acute myeloid leukemia (AML). Methylation-specific PCR (MS-PCR) was used to detect the promoter methylation status of ID4 gene in bone marrow samples from 46 AML patients with different subtypes and stage of disease and from 10 patients with iron deficiency anemia (IDA) as a control. The results showed that ID4 gene in bone marrow of IDA patients was completely non-methylated, while ID4 gene methylation was found in 39 out of 46 AML patients (positive rate 84.8%). The positive rates of ID4 gene methylation in different FAB types M₁, M₂, M₃, M₄, M₅, M₆ were 100% (4/4), 75% (9/12), 100% (8/8), 77.8% (7/9), 81.8% (9/11), 100% (2/2) respectively. The positive rates of ID4 gene methylation in newly diagnosed and complete remitted of AML patients were 90% (27/30) and 63.3% (7/11) respectively; ID4 methylation was detected in 5 relapsed and refractory AML patients. There were statistically significant differences in ID4 gene methylation between AML and IDA patients (p < 0.01). It is concluded that compared with IDA patients, ID4 gene methylation changes of different degrees occur in AML patients with different subtypes and stages, which suggests that ID4 gene methylation may be an early molecular event in the process of AML.

Effect of 5-Aza-CdR on biological activity and inhibitor of DNA binding 4 gene expression in human erythroleukemia cell line K562 / 中国实验血液学杂志

This study was aimed to investigate the effect of 5-Aza-CdR on the biological activity of human erythroleukemia cell line K562 and the expression of inhibitor of DNA binding 4 (ID4). ID4 methylation in K562 cell line was detected by methylation-specific PCR. RQ-PCR was used to analyze the expression levels of ID4 mRNA in K562 cell line treated by different concentrations of 5-Aza-CdR. Cell apoptosis rate and cell cycle were analyzed by flow cytometry. The result showed that ID4 gene methylation existed in K562 cells, ID4 mRNA expression in K562 cells treated with 5-Aza-CdR increased in a concentration-dependent manner, the difference between experimental groups was statistical significant (p < 0.01). The 5-Aza-CdR could enhance the apoptotic rate of K562 cells in time and dose-dependent manner, the apoptotic rate of K562 cells highly correlated to relative expression level of ID4 mRNA (r = 0.95). After the K562 cells were treated by 5-Aza-CdR for 48 hours, cells in G(0)/G(1) phase increased, cells in G(2)/M phase decreased along with enhancement of drug concentration. It is concluded that methyltransferase inhibitor 5-Aza-CdR can re-express the silent ID4 gene in K562 cells. The upregulation of ID4 may be a key factor to give rise to cell apoptosis, and the cell cycle of K562 cells can be arrested by 5-Aza-CdR.

Methylation status of id4 gene promoter in patients with chronic myeloid leukemia / 中国实验血液学杂志

This study was purposed to investigate the methylation status of id4 gene promoter in patients with chronic myeloid leukemia (CML) and explore the relationship between methylation of the id4 gene and progress of CML. The methylation status of id4 gene in 48 chronic myeloid leukemia patients and 10 healthy individuals was detected by using methylation-specific polymerase chain reaction (MS-PCR). The results showed that id4 gene was unmethylated in bone marrow samples from both healthy individuals and CML patients in chronic phase (CP). The rate of id4 gene methylation in both CML patients in accelerated phase (AP) and blast crisis (BC) was 66%, and was higher than those of CML patients in CP phase. There was significant difference between them (p < 0.05). In one CML patient who received a serial observations, the status of id4 was unmethylated in CP, but it was methylated in AP and BC phase. It is concluded that the id4 gene in CML patients is unmethylated in CP, while it is methylated in AP or BC. The detection of id4 gene methylation status may be useful for monitoring disease advance in CML and may be used as a marker of disease progression in CML.

ID4 methylation patterns in childhood T line and B line lymphocytic leukemia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the relationship of methylation of inhibitor of DNA binding 4 (ID4) gene core promoter region with childhood T line, B line and T/B acute lymphocytic leukemia (ALL).</p><p><b>METHODS</b>Methylation-specific polymerase chain reaction (MS-PCR) was used to detect the methylation status of ID4 promoter region in 18 children with newly-diagnosed ALL (2 cases of T-ALL, 13 cases of B-ALL and 3 cases of T/B-ALL). Thirty-four hospitalized children with non-tumor disease served as the control group.</p><p><b>RESULTS</b>The complete methylation rate of ID4 gene promoter region (15/18, 83%) was significantly higher than the partial methylation rate (3/18, 17%) in the 18 ALL children (P<0.05). The complete methylation rate of ID4 gene promoter region in children with T-ALL, B-ALL and T/B-ALL (50%, 85% and 100% respectively) was significantly higher than that in the control group (18%; P<0.05). In contrast, the partial methylation rate and non-methylation rate in the three ALL groups were significantly lower than those in the control group (P<0.05). There were no statistically significant differences in the methylation patterns among the B-ALL, T-ALL and T/B-ALL cases.</p><p><b>CONCLUSIONS</b>The methylation of ID4 promoter region may be related to the pathogenesis of childhood ALL. The methylation patterns of ID4 promoter region are identical in B-ALL, T-ALL and T/B-ALL.</p>

Cloning of ID4 gene expression regulation promoter and subcloning of recombinant ID4 promoter luciferase reporter / 中国实验血液学杂志

<p><b>UNLABELLED</b>The present study was aimed to clone ID4 gene promoter and upstream regulatory region, and to construct a series of recombinant promoter-luciferase reporter for exploring the mechanism of ID4 gene expression regulation.</p><p><b>METHODS AND RESULTS</b>the upstream 5' flanking sequence of 2242 bp from transcriptional start site (TSS) and downstream 5' non-coding region of 212 bp on ID4 gene were searched out and downloaded from human genome databank of NCBI using whole length of ID4 gene cDNA as a probe; On-line promoter analysis softwares, including TESS and Genomax, were employed to analyze the characteristics of ID4 gene promoter and upstream regulatory elements. Then, based on the analytic results, PCR primers were designed and synthesized. Segmental amplification method was adopted to obtain two fragments of 1829 bp and 784 bp. The two fragments were inserted into the plasmid pGEM-T, transformed into TOP10 competent E. coli., and positive recombinants were screened respectively. Subsequently, restriction enzymes KpnI/NheI and KpnI/EcoRI were used to digest the above-mentioned two plasmids pGEM-T and pGL3, and ligation was completed by T4 DNA ligase. After transformation to TOP10 competent E. coli. and screening of positive colonies, the basic recombinant ID4 gene promoter-pGL3 was successfully constructed. KpnI/NheI double digestion and sequencing showed that the target fragment was 2 459 bp and consistent with the corresponding sequence of GenBank; Using the 2459 bp fragment as a template, 5 pairs of primers with identical 3' terminus and different 5' terminus were designed and synthesized for half-nest PCR amplification. 5 fragments with an interval of approximate 400 bp each other, i.e. 2112 bp, 1703 bp, 1290 bp, 784 bp and 496 bp, were produced and inserted into pGEM-T after recovery and purification for transformation to TOP10 competent E. coli. and screening of positive colonies. After that, KpnI/NheI was used to digest the above-mentioned five pGEM-T recombinant plasmids and pGL3 basic vector, and the ligation was completed by T4 DNA ligase. After transformation to TOP10 competent E. coli. and screening for positive colonies, 5 subcloned recombinants of ID4 gene promoter and pGL3 Basic vector cells were constructed. In conclusion, 2.5 kb ID4 gene promoter with upstream expression regulatory sequence was successfully cloned and a series of ID4 promoter subclone-pGL3-Basic recombinant were constructed for further researches on activity, expression regulation and function of ID4 promoter.</p>

Clinical significance of zo-1 and id4 gene abnormal methylation in multiple myeloma / 中国实验血液学杂志

Multiple myeloma (MM) is an incurable heterogeneous disease derived from malignant clonal expansion of plasma cells. The evaluation of prognosis, detection of minimal residual disease (MRD) and treatment of MM are unclear for decades. Recently, Velcade and autotransplantation have been broadly applied to MM patients and achieved better outcomes, but there is yet no effective and universal marker for MRD detection in MM. Both genetic and epigene-tic aberrations play important roles in the pathogenesis and development of cancer. Our preliminary data showed that aberrant promoter methylation of zo-1 and id4 genes was correlated with their gene silencing in several types of hematological malignancies. Therefore, this study was aimed to identify the promoter methylation status of zo-1 and id4 genes in MM and their relationship with the prognosis, MRD and treatment of MM. The methylation status of zo-1 and id4 genes of MM cell lines U266, H929 and IM9 was tested by using MS-PCR; the methylation status of zo-1, id4 gene promoters in bone marrow samples of 20 MM patients and 6 healthy persons was detected by MS-PCR. The results showed that the zo-1, id4 gene in MM cell lines all were methylation positive (complete or partial methylation), the zo-1, id4 gene in samples of 5 healthy persons all were completely unmethylated. The methylation positive rate of zo-1 and id4 genes were 50% and 85% respectively, which were significantly higher than that in normal bone marrow (0%). The coverage rate of zo-1 and id4 gene methylation was 95%. There were no significant differences in the methylation status of both genes among the patients with different heavy chains, different light chains and symptoms. It is concluded that the change of zo-1, id4 genes methylation status occurs in MM patients and has specificity, which may be a new gene marker of MM, methylation analysis of zo-1 and id4 genes may be important for MRD monitoring in patients with MM.

Preliminary study on difference of Id4 gene methylation in various types of myelodysplastic syndromes / 中国实验血液学杂志

The aim of this study was to investigate the difference of Id4 gene promoter methylation in patients with different subtypes of myelodysplastic syndromes (MDS). By using MS-PCR method, the methylation status of Id4 gene was detected in 50 patients with different subtypes of MDS. Id4 methylation was also detected in bone marrow samples from patients with iron deficiency anemia which served as control. The results showed that Id4 gene was unmethylated in all of bone marrow samples from controls. In various subtypes of MDS patients, the rate of Id4 gene methylation was different. No Id4 methylation was found in 6 cases of RA, 2 cases of RARS and 4 cases of MDS-U. Id4 methylations was found in 2 out of 18 patients with RCMD. Id4 methylation in 3 out of 12 patients with RAEBI and other 3 out 8 patients with RAEBII were found. In groups with blast ratio lower or higher than 5%, the incidence of Id4 gene methylation were 6.7% and 30% respectively, so that there was significant difference. In tentative conclusion, Id4 gene methylation possibly is found in MDS patients with higher ratio of blast cells.

Significance of Id4 gene methylation in monitoring efficacy of allo-PBSCT for treatment of acute leukemias / 中国实验血液学杂志

This study was purposed to investigate the significance of Id4 gene methylation in monitoring the efficacy of allo-PBSCT for treatment of acute leukemias. MS-PCR method was used to detect Id4 gene methylation in bone marrow samples from 29 patients with acute leukemia before and at 1, 3, 6 and 12 months after allo-PBSCT. The results showed that the Id4 gene was methylated in 18 patients before allo-PBSCT, out of which Id4 gene methylation in 8 patients could be detected sustainedly after allo-PBSCT, whereas among remaining 11 patients with Id4 gene unmethylation before PBSCT, the Id4 gene of only one case was found to be methylated after PBSCT. Out of 9 patients with Id4 gene methylation after allo-PBSCT, 4 had relapse during the follow-up. 20 patients with Id4 gene unmethylation after allo-PBSCT were in continuously complete remission status. Id4 gene methylation was found more frequently between 6 months and 1 year after allo-PBSCT. It is concluded that detecting Id4 gene methylation is important for the AL patients who underwent allo-PBSCT. Choosing the patients with Id4 gene unmethylaiton to receive allo-PBSCT may help to reduce relapse rate. After allo-PBSCT, Id4 gene methylation status can be regarded as an indicator for predicting prognosis of acute leukemias.

Investigation on MS-PCR as a method for detecting minimal residual disease in acute leukemia / 中国实验血液学杂志

The aim of this study was to investigate the feasibility of monitoring minimal residual disease (MRD) of leukemia with methylation specified-polymerase chain reaction (MS-PCR). The HL-60 cells with Id4 gene complete methylation and Hek937 cells with Id4 gene complete unmethylation were mixed in accordance with different ratios of cells and were divided into 3 groups: group A (10% HL-60 + 90% Hek937), group B (1% HL-60 + 99% Hek937) and group C (0.1% HL-60 + 99.9% Hek937). The MS-PCR technique was used to detect the methylation status of Id4 gene in different ratios of leukemia cells. The results indicated that the methylation specific amplification of Id4 gene with 155 bp was observed in HL-60 cells showing complete methylation of Id4 gene; while the unmethylation specific amplication of Id4 gene with 156 bp was found in Hek937 cells, showing complete unmethylation. The methylation specific amplification of Id4 gene with 155 bp and unmethylation specific amplification of Id4 gene with 156 bp were simultaneously detected in A, B and C groups, which showed the expression of Id4 gene methylation. In conclusion, the MS-PCR technique can detect the Id4 gene methylation in leukemia cell sample containing 0.1% of HL-60 cells, moreover the Id4 gene methylation in various leukemia cells shows no significant difference, thereby use of MS-PCR to detect the Id4 methylation level may be a potential approach for monitoring of MRD. Id4 gene promoter methylation is a candidate of biomarker for MRD detection in acute leukemias.

Differential Methylation Pattern of ID4, SFRP1, and SHP1 between Acute Myeloid Leukemia and Chronic Myeloid Leukemia

To gain insight into the differential mechanism of gene promoter hypermethylation in acute and chronic leukemia, we identified the methylation status on one part of 5'CpG rich region of 8 genes, DAB2IP, DLC-1, H-cadherin, ID4, Integrin alpha4, RUNX3, SFRP1, and SHP1 in bone marrows from acute myeloid leukemia (AML) and chronic myeloid leukemia (CML) patients. Also, we compared the methylation status of genes in AML and CML using methylation-specific PCR (MSP). The frequencies of DNA methylation of ID4, SFRP1, and SHP1 were higher in AML patients compared to those in CML patients. In contrast, no statistical difference between AML and CML was detected for other genes such as DLC-1, DAB2IP, H-cadherin, Integrin alpha4, and RUNX3. Taken together, these results suggest that these methylation-controlled genes may have different roles in AML and CML, and thus, may act as a biological marker of AML.