Ju Bai

Serum peptidome based biomarkers searching for monitoring minimal residual disease in adult acute lymphocytic leukemia

BackgroundThe persistence of minimal residual disease (MRD) during therapy is the strongest adverse prognostic factor in acute lymphocytic leukemia (ALL). This study was to identify serum candidate peptides for monitoring MRD in adult ALL.ResultsA total of 33 peptides in the molecular weight range of 1000-10000 Da were detected using ClinProt system and statistically different between adult patients with ALL and healthy controls. Quick classifier (QC) algorithm was used to obtain a diagnostic model consisting of five peptides that could discriminate patients with ALL from controls with a high sensitivity (100%) and specificity (96.67%). The peptides in the QC model were identified as fibrinogen alpha chain (FGA), glutathione S-transferase P1 (GSTP1), isoform 1 of fibrinogen alpha chain precursor, platelet factor 4 (PF4) by high pressure/performance liquid chromatography mass spectrometry/mass spectrometry. Relative intensities of the five peptides were compared among ALL different groups for the potential importance of MRD evaluation in ALL. The peptides with increased relative intensities in newly diagnosed (ND) ALL patients were found to be decreased in their relative intensities after complete remission (CR) of adult ALL. When ALL patients were refractory & relapsed (RR), relative intensities of the peptides were elevated again. Peptides with decreased relative intensities in ND and RR ALL patients were found to be increased in their relative intensities when ALL patients achieved CR. The findings were validated by ELISA and western blot. Further linear regression analyses were performed to eliminate the influence of platelet and white blood cell counts on serum protein contents and indicated that there were no correlations between the contents of all four proteins (PF4, connective tissue active peptide III, FGA and GSTP1) and white blood cell or platelet counts in ALL different groups and healthy control.ConclusionsWe speculate the five peptides, FGA, isoform 1 of fibrinogen alpha chain precursor, GSTP1, PF4 and connective tissue active peptide III would be potential biomarkers for forecasting relapse, monitoring MRD and evaluating therapeutic response in adult ALL.

MicroRNA: an important regulator in acute myeloid leukemia

MicroRNAs (miRNAs) are a general class of endogenous non‐coding RNAs with a length of 22 nucleotides, widely existing in diverse species and playing important roles in malignancies initiation and progression. MiRNAs are essential to many in vivo biological processes such as cell proliferation, apoptosis, immune response, and tumorigenesis. Significant progress till date has been made in understanding the roles of microRNAs in normal hematopoiesis and hematopoietic malignant diseases. In this review, we summarize the particular signatures of microRNAs in acute myeloid leukemia (AML) patients with specific karyotype and the clinical significance of microRNAs in early diagnosis and treatment. MicroRNAs hypermethylation was also proved to correlate with the pathogenesis of AML. However, the target genes and exact pathways of microRNAs participating in these processes are still unknown and more efforts need to be made in the near future.

Expression, regulation and function of miR-495 in healthy and tumor tissues (Review)

MicroRNA-495 (miR-495) is a small non-coding RNA encoded by a gene located on chromosome 14 (14q32.31). Its expression is regulated by the transcription factors EF12 and EF47, in addition to promoter methylation status and the fusion oncoprotein mixed-lineage leukemia-AF9. Previous studies suggest that miR-495 is involved in various developmental, immunological and inflammatory processes in healthy tissue, and in the proliferation, invasion, metastasis and drug resistance of cancer cells. The role miR-495 serves in tumors is controversial. miR-495 primarily functions as a tumor suppressor; however, in a number of cases it acts as an oncogene. miR-495 has potential applications as a diagnostic and prognostic marker, and as a therapeutic target for genetic and pharmacological manipulation in the treatment of various diseases.

Focusing on long non-coding RNA dysregulation in newly diagnosed multiple myeloma

Aims: Multiple myeloma (MM) is an incurable hematological cancer with a higher rate of relapse. Alterations in the function of long non‐coding RNAs (lncRNAs) promote the progression and metastasis of cancer. We carry out this study to explore the expression profile of differently expressed lncRNAs in newly diagnosed MM. Main methods: The Bone marrows we analyzed were obtained from five MM and five IDA patients (serving as controls). Arraystar Human LncRNA Array V4.0 was used to profile expression of lncRNAs and mRNAs. Gene ontology (GO) and pathway analysis were utilized to understand the biological roles of differently expressed genes, while Database for Annotation, Visualization and Integrated Discovery (DAVID) was used for constructing the lncRNA‐mRNA co‐expression network. Quantitative polymerase chain reaction (qRT‐PCR) was performed to confirm the expressions of dysregulated lncRNAs. Key findings: Bioinformatic analysis of the lncRNA expression identified >3000 dysregulated lncRNAs (difference ≥ 2‐fold) in MM samples. GO and pathway analysis revealed that ECM‐receptor and cell cycle pathway‐related genes were significantly associated with MM. Four dysregulated lncRNAs were confirmed by qRT‐PCR. Among them, the expression of ST3GAL6‐AS1, LAMA5‐AS1and RP11‐175D17.3wereassociated with stage and risk status of MM. On the basis of GEO public database analysis, LAMA5‐AS1 was related with an overall survival rate of MM patients. Significance: These results reveal the feasible functions of lncRNAs in pathogenesis of MM. Further studies are required to explore whether these lncRNAs could serve as candidate therapeutic targets and new molecular biomarkers for MM.

Circ-ANAPC7 is Upregulated in Acute Myeloid Leukemia and Appears to Target the MiR-181 Family

Background/Aims: Circular RNAs (circRNAs) are a family of novel non-coding RNAs associated with various diseases, especially cancer. Recent studies have demonstrated that circRNAs participate in pathogenesis mainly by acting as microRNA (miRNA) sponges. The expression profile of circRNAs in acute myeloid leukemia (AML) has rarely been reported. Methods: Profiles of circRNAs were analyzed using an Arraystar human circRNA microarray with 5 bone marrow samples from patients with newly diagnosed AML and 5 from patients with iron-deficiency anemia. Quantitative reverse transcription PCR was used to validate the expression pattern of circRNAs. Furthermore, circRNA–miRNA network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were applied. Results: CircRNA microarray analysis revealed that 698 circRNAs were differentially expressed in AML patients, with 282 circRNAs found to be upregulated and 416 to be downregulated. Quantitative reverse transcription PCR showed that circ-ANAPC7 was significantly upregulated in AML. Bioinformatics analysis predicted that circ-ANAPC7 acts as a sponge for the miR-181 family, KEGG analysis revealed that it is associated with cancer-related pathways, and GO analysis indicated that most of its target genes are involved in biological processes. Conclusions: These findings show that circ-ANAPC7 is a promising biomarker for AML, and that it might participate in AML pathogenesis by acting as a sponge for the miR-181 family.

Expression profile analysis of long non-coding RNA in acute myeloid leukemia by microarray and bioinformatics

Long non‐coding RNAs (lncRNAs) are transcripts longer than 200 nt that are involved in tumorigenesis and play a key role in cancer progression. To determine whether lncRNAs are involved in acute myeloid leukemia (AML), we analyzed the expression profile of lncRNAs and mRNAs in AML. Five pairs of AML patients and iron deficiency anemia (IDA) controls were screened by microarray. Through coexpression analysis, differently expressed transcripts were divided into modules, and lncRNAs were functionally annotated. We further analyzed the clinical significance of crucial lncRNAs from modules in public data. Finally, the expression of three lncRNAs, RP11‐222K16.2, AC092580.4, and RP11‐305O.6, were validated in newly diagnosed AML, AML relapse, and IDA patient groups by quantitative RT‐PCR, which may be associated with AML patients’ overall survival. Further analysis showed that RP11‐222K16.2 might affect the differentiation of natural killer cells, and promote the immunized evasion of AML by regulating Eomesodermin expression. Analysis of this study revealed that dysregulated lncRNAs and mRNAs in AML vs IDA controls could affect the immune system and hematopoietic cell differentiation. The biological functions of those lncRNAs need to be further validated.

Granulocyte colony stimulating factor priming chemotherapy is more effective than standard chemotherapy as salvage therapy in relapsed acute myeloid leukemia

INTRODUCTION AND OBJECTIVE To improve the complete remission (CR) rate of newly diagnosed acute myeloid leukemia (AML) patients and alleviate the severe side effects of double induction chemotherapy, we combined a standard regimen with granulocyte colony-stimulating factor (G-CSF) priming chemotherapy to compose a new double induction regimen for AML patients who failed to achieve CR after the first course. PATIENTS AND METHODS Ninety-seven patients with AML who did not achieve CR after the first course of standard chemotherapy were enrolled. Among them, 45 patients received G-CSF priming combined with low-dose chemotherapy during days 20-22 of the first course of chemotherapy, serving as priming group, 52 patients were administered standard chemotherapy again, serving as control group. RESULTS Between the two groups there were no differences in the French-American-British (FAB) classification, risk status, the first course of chemotherapy, blood cell count or blasts percentage of bone marrow before the second course. But the CR rate was significantly higher and the adverse effect was much lower in the priming group than the control group. Cox multivariate regression analysis showed that WBC level before the second course and the selection of the second chemotherapy regimen were two independent factors for long survival of patients. DISCUSSION These results elucidate that standard chemotherapy followed by G-CSF priming new double induction chemotherapy is an effective method for AML patients to improve CR rate and reduce adverse effects.