Lower Serum miR-145 Predicts Poor Prognosis in Patients with Acute Myeloid Leukemia.

BACKGROUND: The current study mainly aims to evaluate the role and clinical significance of miR-145 in the progression of AML. METHODS: Serum and bone marrow nucleated cells (BMNc) were collected and the level of miR-145 was detected by RT-PCR. Pearson's correlation assay was carried out to analyze the correlation between serum miR-145 and clinical index. The receiver operating characteristic (ROC) curve was constructed to determine the diagnosis value of serum miR-145. RESULTS: MiR-145 was significantly decreased in serum and BMNc of patients with AML compared with the control group. Pearson's correlation assay showed that serum miR-145 was positively correlated with miR-145 levels in BMNc. Further study showed that the level of serum miR-145 was much lower in AML patients with initial WBC count ≥ 50 x 109/L than that of WBC count < 50 x 109/L. Moreover, the level of serum miR-145 in prednisone poor responders was significantly lower than that in prednisone good responders. Compared with minimal residual disease (MRD) < 0.01% group, serum miR-145 was much lower in AML patients with MRD ≥ 0.01% group. Pearson's correlation analysis showed that serum miR-145 was positively correlated with MRD. In addition, miR-145 diagnosed AML with an AUC of 0.915 (95% confidence interval: 0.828 to 1.000; p < 0.001). CONCLUSIONS: The level of miR-145 in serum and BMNc of AML patients was significantly lower than those of the control group. Serum miR-145 was related to poor prognosis and disease recurrence of AML.

Impact of "a" determinant mutations on detection of hepatitis B surface antigen (HBsAg) in HBV strains from Chinese patients with occult hepatitis B.

This study was designed to detect mutations that occur within the "a" determinant in the S gene of the hepatitis B virus (HBV) in patients with occult hepatitis B (OHB), and to analyze the influence of these mutations on expression and reactivity of the hepatitis B surface antigen (HBsAg). Twenty-three certified OHB samples were compared to 32 HBsAg positive samples from patients with chronic hepatitis B. The median HBV DNA levels in the OHB group were significantly lower than those in the control group (P < 0.0001). Mutations within the "a" determinant were analyzed by gene amplification and sequencing. This revealed mixed infections in which clones within a sample displayed either different mutations or mutations in association with clones that exhibited wild type amino acid patterns. Sequencing analysis also showed a significant difference between the proportions of amino acid mutations observed in the OHB and control groups. Seven recombinant S (rS) proteins with corresponding OHB mutations and three wild type alleles were expressed and purified in the Pichia pastoris expression system to preserve conformational attributes, and their reactivity analyzed using six commercial HBsAg assays. The OHB sera were HBsAg nonreactive while the rS proteins with corresponding OHB mutations were universally reactive. Thus, we postulate that the reduced binding affinity between mutated HBsAg and its antibody may not be as important in defining OHB as is the effect of specific mutations in the preS/S region of the genome that affect the synthesis and secretion of the S protein and/or the virion.

Molecular analysis of the hepatitis B virus presurface and surface gene in patients from eastern China with occult hepatitis B.

This study was designed to detect and analyze mutations that occur within the presurface and surface (pre-S/S) gene of HBV in patients with occult hepatitis B, and determine their relationship to that disorder. Among 254 HBsAg negative samples of blood collected in eastern China, 183 were positive for anti-HBc alone, 61 were positive for anti-HBe alone, and 10 samples were positive for HBeAg. Within this group, 15 samples were found to be HBV DNA positive by real-time PCR and were designated Group I. A control group of 28 HBsAg positive samples were chosen at random from patients with chronic hepatitis B and designated Group II. The HBV pre-S/S gene was amplified by PCR and subjected to sequencing analysis. Occult hepatitis B was found in 1.6% of the patients with anti-HBc alone and in 3.3% of those with anti-HBe alone. Occult hepatitis B also was found in all HBsAg negative but HBeAg positive samples. Sequencing analysis showed a significant correlation between point mutations within the "a" determinant and occult hepatitis B (P < 0.0001), and a close relationship between pre-S deletion mutations and occult hepatitis B (P = 0.06). There were unique amino acid mutations at the G145 position other than G145R. The HBV DNA levels in patients with occult hepatitis B were significantly lower than those found in the control group. The "a" determinant mutations and pre-S deletions may play important roles in occult hepatitis B by affecting the expression, synthesis and secretion of the S protein and by impeding viral release and replication.

PreS deletion mutations of hepatitis B virus in chronically infected patients with simultaneous seropositivity for hepatitis-B surface antigen and anti-HBS antibodies.

Hepatitis B surface antigen (HBsAg) and anti-HBs antibodies (anti-HBs) may coexist in certain chronic hepatitis B (CHB) patients. This study was designed to further explore the relationship between this coexistence and hepatitis B Virus (HBV) preS deletions. Sera of 28 patients carrying both HBsAg and anti-HBs (Group I) and those of another 28 HBsAg positive but anti-HBs negative patients (Group II) were collected from CHB patients. Direct sequencing of polymerase chain reaction products or sequencing of clones was applied to both groups to determine sequences of HBV preS and S genes. Genotyping of the S gene indicated that all sampled HBVs were either Genosubtype Ba or Genosubtype Ce. Seven samples in Group I harbored HBV preS deletion mutations. Three of the seven samples showed large deletion mutations in 3' terminus of preS1 and co-existence of the mutant type and the full-length wild type, and the remaining four samples showed deletion mutations in 5' terminus of preS2. All mutant strains were found to be genosubtype Ce. Only two samples in Group I showed G145R/A mutation. Only one sample in Group II contained preS deletion mutation. It is therefore concluded that HBV preS deletion mutations are likely to be related to the coexistence of HBsAg and anti-HBs in CHB patients (P-value = 0.024). Some immune reactions may select for the preS deletion in CHB patients with anti-HBs, the possible marker for immune selection.