New insights of acylation stimulating protein in modulating the pathological progression of metabolic syndromes.

Obesity is associated with insulin resistance, hypertension, and coronary artery diseases which are grouped as metabolic syndrome. Rather than being a storage for energy, the adipocytes could synthesis and secret diverse hormones and molecules, named as adipokines. Under obese status, the adipocytes are dysfunctional with excessively producing the inflammatory related cytokines, such as interleukin 1 (IL-1), IL-6, and tumor necrosis factor α (TNF-α). Concerning on the vital role of adipokines, it is proposed that one of the critical pathological factors of obesity is the dysfunctional adipocytic pathways. Among these adipokines, acylation stimulating protein, as an adipokine synthesized by adipocytes during the process of cell differentiation, is shown to activate the metabolism of triglyceride (TG) by regulating the catabolism of glucose and free fatty acid (FFA). Recent attention has paid to explore the underlying mechanism whereby acylation stimulating protein influences the biological function of adipocyte and the pathological development of obesity. In the present review, we summarized the progression of acylation stimulating protein in modulating the physiological and hormonal catabolism which affects fat distribution. Furthermore, the potential mechanisms which acylation stimulating protein regulates the metabolism of adipose tissue and the process of metabolic syndrome were also summarized.

Relationship between inflammatory-related cytokines with aortic dissection.

Aortic dissection, characterized by severe intramural hematoma formation and acute endometrial rupture, is caused by excessive bleeding within the aortic wall or a severe tear within the intimal layer of the aorta, which subsequently promotes the separation or dissection in the layers of the aortic wall. Epidemiological surveys showed that aortic dissection was most observed among those patients from 55 to 80 years of age, with a prevalence of approximately 40 cases per 100,000 individuals per year, posing serious risks to future health and leading to high mortality. Other risk factors of aortic dissection progression contained dyslipidemia, hypertension, and genetic disorders, such as Marfan syndrome. Currently, emerging evidence indicates the pathological progression of aortic dissection is significantly complicated, which is correlated with the aberrant infiltration of pro-inflammatory cells into the aortic wall, subsequently facilitating the apoptosis of vascular smooth muscle cells (VSMCs) and inducing the aberrant expression of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interferon (IF). Other pro-inflammatory-related cytokines, including the colony-stimulating factor (CSF), chemotactic factor, and growth factor (GF), played an essential function in facilitating aortic dissection. Multiple studies focused on the important relationship between pro-inflammatory cytokines and aortic dissection, which could deepen the understanding of aortic dissection and further guide the therapeutic strategies in clinical practice. The present review elucidated pro-inflammatory cytokines' functions in modulating the risk of aortic dissection are summarized. Moreover, the emerging evidence that aimed to elucidate the potential mechanisms wherebyvarious pro-inflammatory cytokines affected the pathological development of aortic dissection was also listed.

[Significance of Morphological Examination, Cytochemical Staining Combined with Bone Marrow Biopsy in Differential Diagnosis of Myelodysplastic Syndrome with Low Blasts and Hemolytic Anemia].

OBJECTIVE: To explore the value of morphological examination, cytochemical staining combined with bone marrow biopsy in the differential diagnosis between myelodysplastic syndrome (MDS) with low blasts and hemolytic anemia (HA). METHODS: The clinical data of 85 cases of myelodysplastic syndrome with low blasts (< 5%) and 61 patients with hemolytic anemia in Chinese PLA's Gerneral hospital from September 2009 to March 2015 were retrospectively analysed. The clinical characteristics, cytogenetic and molecular features, bone marrow cell count and morphology features, cytochemical staining results and bone marrow biopsy features of above-methioned patients were compared. RESULTS: There was no significant difference (P > 0.05) in clinical data between MDS group and HA group. Megakaryocytic dysplasia-positive rate, and ring sideroblasts positive rate, and PAS positive rate were significantly higher in MDS group than those that in HA group (P < 0.05). Abnormal localization of immature precursors (ALIP) and megakaryocytic dysplasia positive rate in bone marrow biopsy were significantly higher in MDS group than those that in HA group (P < 0.05), 90.6% of MDS with low blasts patients were identifiable by combined detections. CONCLUSION: Combining detection of morphology, cytochemistry staining and bone marrow biopsy has been confirmed to be more useful for differential diagnosis between MDS with low blasts and HA.

Quantitative Detection of ID4 Gene Aberrant Methylation in the Differentiation of Myelodysplastic Syndrome from Aplastic Anemia.

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

[Clinical Implications on ZO-1 Gene Methylation in Myelodysplastic Syndrome Progression].

OBJECTIVE: To investigate the clinical significance of ZO-1 gene methylation level in MDS progression in order to provide a theoretical basis for evaluating progrosis of MDS patients. METHODS: The methylation specific PCR (MS-PCR) was performed to evaluate the ZO-1 gene methylation status in bone marrow samples of normal persons as control (NC). MDS and AML patients, the bisulfite sequencing PCR (BSP) was applied to detect the ZO-1 gene methylation status in serial bone marrow samples of MDS-RA, MDS-RAEB and AML stages of a MDS patients. RESULTS: The possitive rate of ZO-1 gene methylation in samples of NC, MDS and AML patients displayed significant difference; in sample of NC group the positive of ZO-1 gene methylation was not observed, but the positive rate of ZO-1 gene methylation in samples of AML patients was highest (65.0%), the proportion of ZO-1 gene methylation in myeloid blast count of MDS/AML patients was higher (P=0.000). The serial samples in one MDS patient showed that along with progress of disease, the positive rate of ZO-1 gene methylation in MDS-RA, MDS-RAEB and AML stages was found to be obvious different (P=0.000), the positive rate of ZO-1 gene methylation in AML stage was highest (64.65%). CONCLUSION: The high methylation in promoter region of ZO-1 gene has been found in MDS/AML patients, and along with clonal proliferation, the positive rate of ZO-1 methylation and positive froguency of methylation sites increase graduatly which suggests that the MDS progresses in a certain degree, and the ZO-1 gene methylation level may be used as an new indicator for monitoring desease progression from MDS to AML.

[Clinical significance of bone marrow morphological examination and tumor marker detection for lymphoma diagnosis and prognosis].

OBJECTIVE: This study was aimed to evaluate the significance of bone marrow(BM) morphological examination and many tumor marker(TM) detection, especially carcinoembryonic antigen (CEA), cancer antigen 125(CA125), cancer antigen 15-3 (CA15-3) and serum ferritin (SF) for lymphoma diagnosis and prognosis. METHODS: A total of 47 confirmed patients with lymphoma in our hospital from January 2012 to October 2013 and 20 health peoplels as normal controls were performed with bone marrow morphological examination, at the same time, the electrochemistry luminescent technique was applied for detecting levels of TM (especially CEA, CA125, CA15-3 and SF) in serum samples of lymphoma patient and normal controls, then the BM immature lymphocyte counts of these people and clinical parameters were analyzed for diagnosis and prognosis. RESULTS: There was significant differences in all the four TM levels between serum samples of lymphoma patients and normal control (P=0.029, P=0.000, P=0.005, P=0.000). These TM levels had no correlation with age, sex white blood cell, lymphocyte, platelet counts and anemia of lymphoma patients (P>0.05). It was also found that the patients with elevated TM levels had high BM immature lymphocytes (lymphoma cells) counts, B symptoms, advanced clinical stage and high IPI index (P<0.05). The CA15-3 and SF levels in serum samples of lymphoma patients with BM infiltration were higher than that in lymphoma patients without BM infiltration (P=0.002, P=0.000). CONCLUSION: Combination of BM morphological examination with serum TM level detection plays an important role in diagnosis, clinical stage and prognosis evaluation of lymphoma patients. It is also very important for assessing BM infiltration status of lymphoma patients.

[Clinical Significance of ID4 Gene Mehtylation in Demethylation-Treated MDS Cell Line and 2 MDS Patients].

OBJECTIVE: To evaluate significance of ID4 gene mehtylation in demethylating myelodysplastic syndrome(MDS) cell Line MUTZ1 and 2 patients with MDS. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Clinical implications of the quantitative detection of ID4 gene methylation in myelodysplastic syndrome.

BACKGROUND: Myelodysplastic syndrome (MDS) eventually transforms into acute leukemia (AL) in about 30% of patients. Hypermethylation of the inhibitor of DNA binding 4 (ID4) gene may play an important role in the initiation and development of MDS and AL. The aim of this study was to quantitatively assess ID4 gene methylation in MDS and to establish if it could be an effective method of evaluating MDS disease progression. METHODS: We examined 142 bone marrow samples from MDS patients, healthy donors and MDS-AL patients using bisulfite sequencing PCR and quantitative real-time methylation-specific PCR. The ID4 methylation rates and levels were assessed. RESULTS: ID4 methylation occurred in 27 patients (27/100). ID4 gene methylation was more frequent and at higher levels in patients with advanced disease stages and in high-risk subgroups according to WHO (P < 0.001, P < 0.001, respectively) and International Prognostic Scoring System (IPSS) (P = 0.002, P = 0.007, respectively) classifications. ID4 methylation levels changed during disease progression. Both methylation rates and methylation levels were significantly different between healthy donor, MDS patients and patients with MDS-AL (P < 0.001, P < 0.001, respectively). Multivariate analysis indicated that the level of ID4 methylation was an independent factor influencing overall survival. Patients with MDS showed decreased survival time with increased ID4 methylation levels (P = 0.011, hazard ratio (HR) = 2.371). Patients with ID4 methylation had shorter survival time than those without ID4 methylation (P = 0.008). CONCLUSIONS: Our findings suggest that ID4 gene methylation might be a new biomarker for MDS monitoring and the detection of minimal residual disease.

Procalcitonin could be a reliable marker in differential diagnosis of post-implantation syndrome and infection after percutaneous endovascular aortic repair.

BACKGROUND: Thoracic endovascular aortic repair (TEVAR) is an emerging treatment modality, which has been rapidly embraced by clinicians treating thoracic aortic disease. However, the clinical manifestations of systemic inflammatory response after TEVAR as post-implantation syndrome (PIS) resemble the perioperative infection. This study aimed to evaluate changes and diagnostic value of procalcitonin (PCT) and other traditional inflammatory markers for infections after TEVAR. METHODS: We conducted a prospective clinical study that enrolled 162 consecutive aortic dissection cases, who underwent TEVAR in our institution between July 2011 and November 2012. The PCT, C-response protein (CRP), erythrocyte sedimentation rate (ESR) and blood routine examination were monitored before the operation and on days 1, 2, 3 and 5 after the operation. The diagnosis of infection was confirmed by the infection control committee with reference to Hospital Acquired Infection Diagnostic Criteria Assessment, released by the Ministry of Health of the People's Republic of China. RESULTS: Post endovascular repair of thoracic aorta, PCT changes significantly at different time points (χ(2) = 13.225, P = 0.021), without significant difference between the PIS group and the control group (0.24 ± 0.04 vs.0.26 ± 0.10, P = 0.804). PCT values were significantly higher in the first day after TEVAR than the preoperative levels (0.18 ± 0.03 vs. 0.11 ± 0.02, P < 0.001). Compared with PIS patients, the level of PCT, CRP, White blood cell (WBC) and neutrophil (NEU) in the infection patients elevated significantly (relatively χ(2) = 6.062, P = 0.048; χ(2) = 6.081, P = 0.048; χ(2) = 11.030, P = 0.004; χ(2) = 14.632, P = 0.001). According to the ROC analysis, the PCT levels in the first day after TEVAR (AUC = 0.785, P = 0.012) had better predictive values of infection than WBC, NEU CRP and ESR (AUC = 0.720, P = 0.040; AUC = 0.715, P = 0.045; AUC = 0.663, P = 0.274; AUC = 0.502, P = 0.991). The best predictive index was the changes of PCT between preoperative and postoperative (PCT), which possess AUC as 0.803 (P = 0.014). And PCT = 0.055 could be considered as an infection diagnosis cutoff value with a sensitivity of 83.3% and specificity 69.0%. CONCLUSIONS: PCT provides better diagnostic value of infection compared with other inflammatory markers. The potential applications of PCT in differential diagnosis of PIS and infection after percutaneous TEVAR deserve further studies.

[Clinical significance of ID4 methylation detection by quantitative methylation-specific PCR in acute leukemia].

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].

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.

Association between lymphoma prognosis and aberrant methylation of ID4 and ZO-1 in bone marrow and paraffin-embedded lymphoma tissues of treatment-naive patients.

The aim of the present study was to investigate the association between lymphoma prognosis and aberrant methylation of inhibitor of DNA binding factor 4 (ID4) and tight junction protein 1 (ZO-1) genes in samples isolated from the bone marrow and paraffin-embedded lymphoma tissues of treatment-naive lymphoma patients. The bone marrow biopsy and paraffin-embedded lymphoma tissue samples from treatment-naive lymphoma patients were obtained, along with corresponding control samples from subjects without lymphoma and from lymph nodes of chronic cholecystitis and reactive lymphadenitis patients. Methylation-specific PCR (MSP) reactions were performed to analyze the methylation status on the promoter regions of ID4 and ZO-1. ID4 and ZO-1 promoter regions in the control group were completely unmethylated, whereas the rates of methylation of ID4 and ZO-1 in paraffin-embedded lymphoma tissues of the lymphoma patients were 80.4 and 84.3%, respectively. The methylation positivity rates of both the ID4 or ZO-1 genes in lymphoma patients were 92.2%, which was significantly higher compared to the rates in the control group (0%). The methylation positivity rates of the ID4 and ZO-1 genes in the bone marrow and paraffin-embedded lymphoma tissues of non-Hodgkin lymphoma patients were significantly higher compared to the rates in the Hodgkin lymphoma patients. The survival rate of lymphoma patients with methylated ID4 was significantly lower compared to that of patients with unmethylated ID4. The methylation of the ID4 and ZO-1 genes may be a specific molecular marker for lymphoma diagnosis. The methylation of the ID4 gene may be an indicator of poor prognosis in lymphoma patients.

[Poliovirus receptor on surface of acute B lymphoid leukemia cells modulated by epigenetic mechanism].

The aim of this study was to identify if the expression of poliovirus receptor (PVR) on the surface of acute B lymphoid leukemia (B-ALL) cells RS4:11 and SUP-B15 is modulated by epigenetic mechanism. B-ALL cell lines RS4:11 and SUP-B15 were treated with demethylation agent. Bisulfite PCR was performed to detect percentage change of the methylated CpG islands in the promoter region of PVR. In the meantime, the expression levels of PVR at the translation and transcription levels were detected by flow cytometry and RT-PCR respectively. The B-ALL cell lines were also treated with histone deacetylase (HDAC) inhibitor. The expression level of the gene mRNA and protein was detected too. The results indicated that after treated with 5-azacytidine, the hypermethylated status of PVR promoter region was partly reversed, and the expression of PVR at both mRNA and protein levels was restored in the meanwhile. HDAC inhibitor suberoylanilide hydroxamic acid could also increase the PVR expression. But there was no synergistic function between hypermethylation and HDAC as for repressing PVR transcription in B-ALL cell lines. It is concluded that the expression of PVR in B-ALL cells is modulated by epigenetic mechanisms. Treatment with corresponding inhibitors can partly restore the gene's expression in both mRNA and protein levels.

Modulation of the poliovirus receptor expression in malignant lymphocytes by epigenetic alterations.

Malignant lymphocytes are characterized by their low expression of poliovirus receptor (PVR), ligand for the activating natural killer (NK) cell receptors, which may explain their insensitivity toward NK cell-based therapeutic approaches. Here, we have studied the mechanism of this defective expression of PVR. We demonstrated that the characterization of NK-insensitive cell lines was of low expression of PVR in both mRNA and surface levels, and that PVR of RAJI cells able to resist NK cells has hypermethylated promoter-associated CpG islands. After treating with 5-azacytidine (5-AZA) (ie, hypomethylation agent) and suberoylanilide hydroxamic acid (SAHA) (ie, histone deacetylase inhibitor), respectively or simultaneously, the abnormal epigenetic status became partly reversed, and the mRNA and surface expression of PVR restored. The expression restoration of the gene enhanced susceptibility of RAJI cells to NK cells but, when the RAJI cells were incubated with the specific blocking antibody for PVR's receptor, the enhanced susceptibility would diminish. Patients with acute myeloid leukemia expressed higher PVR than patients with acute lymphoblastic leukemia in both mRNA and surface levels. Epigenetic modulation of hypermethylation and histone deacetylase is involved in repressing PVR expression in malignant lymphocytes resistant to NK cells.

[Significance of methylation status of zo-1 gene in differential diagnosis for myelodysplastic syndrome].

It is hard to discriminate myelodysplastic syndrome(MDS) from many benign hematological diseases. To identify the methylation status of zo-1 gene in MDS, the methylation specific PCR (MS-PCR) and reverse transcription-PCR (RT-PCR) were applied to detect the MDS cell line MUTZ-1, bone marrow of a healthy donor and an aplastic anemia patient. MS-PCR was also employed to detect the bone marrow of 72 patients with benign hematological diseases, 35 MDS-RA patients, and 20 MDS-like patients. The results showed that MDS cell line MUTZ-1 displayed complete methylation of zo-1 promoter without mRNA expression. Inversely, a patient with benign hematological disease and a donor with normal bone marrow showed complete unmethylation of this gene with unaffected mRNA expression. No zo-1 promoter methylation was detected in patients with benign hematological diseases, while aberrant hypermethylation of zo-1 gene promoter were found in 48.6% (18/37) of MDS-RA patients. The positive rate of zo-1 methylation in MDS-RA patients was higher than that in patients with benign hematological diseases (p < 0.05). Seven suspected MDS patients manifested hypermethylation status of zo-1 gene (7/20), 2 were followed up for 1 year and transformed into MDS. It is concluded that relatively high hypermethylation rate of zo-1 promoter is observed in MDS-RA, and no methylation in patients with benign hematological diseases. Therefore, zo-1 gene hypermethylation may be served as a useful epigenetic marker in the differential diagnosis for MDS.

[Methylation status of id4 gene promoter in patients with chronic myeloid leukemia].

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.

[Clinical significance of zo-1 and id4 gene abnormal methylation in multiple myeloma].

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.

[Methylation status of zo-1 gene promoter in acute leukemia].

This study was purposed to investigate the difference of zo-1 gene promoter methylation between healthy individuals and acute leukemia patients. BS-PCR method was used to detect the status of zo-1 gene methylation in healthy individuals, acute leukemia patients and leukemic cell line NB4 cells. The results showed that zo-1 gene was hypomethylated in bone marrow samples from healthy individuals (1.9%). In newly diagnosed AL and relapsed patients, the rate of zo-1 gene methylation was 93.2% and 66.9% respectively, while it was 16.4% in AL patients in complete remission, which was much higher than that in healthy individuals. There was significant difference between them. It is concluded that as compared with healthy individuals, zo-1 gene in acute leukemia patients is hypermethylated and with different degrees in various phases of leukemia. Analysis of zo-1 gene methylation status may be useful to monitor the development of acute leukemia.

[Methylation status of ZO-1 gene in patients with myelodysplastic syndrome].

The objective of this study was to investigate the methylation status of zonula occluden protein-1 (ZO-1) gene in patients with myelodysplastic syndrome (MDS) and to identify its roles in pathogenesis, development and classification of MDS. 85 patients with MDS and 30 healthy individuals were tested by methylation specific polymerase chain reaction (MS-PCR). The results indicated that no ZO-1 promoter methylation could be detected in healthy controls. methylation of ZO-1 gene promoter of bone marrow was found in 56.5% (48/85) MDS patients. The difference between these two kinds of subjects was statistically significant (p<0.05). The methylation status of ZO-1 gene promoter region in the subtypes of MDS was as following: RA (18/37, 48.6%), RAS (4/6, 67%), RCMD (19/30, 63%), RAEB (7/12, 58%). Every subtype of MDS patients had statistical difference from healthy people (p<0.05), but between the subtypes of MDS there were no significant statistical differences in the methylation status of ZO-1 gene, while the level of ZO-1 promoter methylation in group of RA was lower than that in other groups. It is concluded that the ZO-1 promoter region in bone marrow of MDS patient shows a hypermethylation status, which is specific for MDS. MDS is a common hematologic malignancy with clonal proliferation, it is difficult to differentiate from many other hematologic malignancies in clinical diagnosis. However, the change of ZO-1 gene methylation status is closely related to pathogenesis of MDS, therefore the ZO-1 gene as valuable diagnostic marker has important clinical significance. The ZO-1 gene may be a potential gene related to hematologic malignancies.

Methylation pattern of LRP15 gene in leukemia.

OBJECTIVE: To investigate the methylation status of LRP15 gene in acute leukemia (AL) patients and its role in the tumorigenesis. METHODS: The methylation of LRP15 promoter and first exon of bone marrow mononuclear cells in 73 patients with AL, 10 with chronic leukemia (CL), 9 with hematological benign diseases, and 20 healthy transplantation donors was analyzed by using methylation specific polymerase chain reaction. The methylation of LRP15 gene promoter and first exon in COS7, K562, and HL60 cell lines was also assayed. RESULTS: No LRP15 gene promoter methylation was detected in COS7 cell line. LRP15 gene promoter was methylated in K562 and HL60 cell lines. No deletion of LRP15 gene was detected in all samples. In nearly all French-American-British leukemia subtypes, we found that frequency of LRP15 methylation in adult patients with AL was 71.23% (52/73). There was no detectable methylation in any of the 20 healthy donors and 8 chronic myeloid leukemia patients. The difference in frequency of LRP15 methylation between AL patients and healthy donors or CL patients (10.00%, 1/10) was significant (P < 0.01). Hypermethylation of LRP15 gene was found in 57.14% (16/28) of newly diagnosed AL patients, 83.33% of relapsed AL patients respectively, which was significantly different (P < 0.05). We also demonstrated LRP15 methylation in 55.56% (5/9) adults with benign hematological diseases. CONCLUSIONS: LRP15 methylation changes are common abnormalities in leukemia. LRP15 is postulated to be a tumor suppressor gene.