[Transcriptome sequencing-based classification and quantification of IKZF1 transcript isoforms in B-cell acute lymphoblastic leukemia].

Objective: To classify and quantify IKZF1 mutant transcripts in B-cell acute lymphoblastic leukemia (B-ALL) by RNA sequencing (RNA-seq) and bioinformatics analysis. Methods: A cohort of 263 B-ALL cases was enrolled at Hebei Yanda Ludaopei Hospital from September 2018 to September 2020. An integrated bioinformatics pipeline was developed to adapt the classification and quantification of IKZF1 transcripts from RNA-seq and was applied to sequencing data of these cases. The IKZF1 mutant transcripts classified by RNA-seq analysis were compared with the qualitative reverse transcription PCR (RT-PCR). Results: IKZF1 mutant transcripts were identified in 53 B-ALL patients by RT-PCR and Sanger sequencing, among which IK6 and IK10 transcripts accounted for 67.9% (36/53) and 28.3% (15/53) respectively. Additionally, 2 patients were double positive for IK6 and IK10. RNA-seq analysis identified 51 patients with IKZF1 mutant transcripts. Compared with the RT-PCR result, the detection sensitivity and specificity of RNA-seq analysis reached 94.3% (50/53) and 99.5% (209/210), respectively. Among the 50 patients with IKZF1 mutant transcripts both in RNA-seq and RT-PCR analysis, the ratio of mutant transcripts to total IKZF1 transcripts in 6 patients was 0.14 (0.11, 0.35), which was significantly lower than that of the other 44 patients [0.88 (0.35, 0.97), Z=-3.945,P<0.001]. IKZF1 mutations mostly occurred in Ph+and Ph-like B-ALL, characterized by abnormal JAK-STAT pathway, and B-ALL with PAX5 translocation. Conclusions: Through the optimized bioinformatics analysis process, RNA-seq data can be used to classify and quantitatively analyze IKZF1 transcripts in B-ALL. Furthermore, the relative expression of mutant IKZF1 transcripts was found to cluster into two groups, and IKZF1 mutation was found often accompanied with PAX5 translocations.

[ABO gene subtypes and gene expression analysis in three cases of hematological malignancies patients].

Objective: To explore the application and discovery of genotyping, gene sequencing, and gene expression analysis in the determination of ABO blood group subtypes and antigen expression abnormalities in hematological malignancies patients. Methods: From June 2019 to May 2020, three clinical cases were found with forward and reverse ABO typing discrepancy or atypical serologic agglutination pattern in the laboratory and blood transfusion department of Hebei Yanda Ludaopei Hospital were selected. Sequence-specific primer PCR (PCR-SSP) and Sanger sequencing of ABO gene coding regions were performed to determine the ABO genotypes, and whole transcriptome sequencing was used to analyze ABO and FUT1 gene expression levels. Results: A 12-year-old female acute lymphoblastic leukemia patient was determined as O.01.02 and BA.04 sub-genotype, corresponding to the serological B(A) subtype, and her ABO gene expression was normal (354.80). A 41-year-old female acute myeloid leukemia patient was determined as A1.02 and B.01 genotype, corresponding to the serological A(1)B phenotype, and her ABO gene expression was significantly reduced (45.70). A 42-year-old male with myelodysplastic syndrome and myelofibrosis was determined as A1.02 and A2.05 sub-genotype, corresponding to the serological A(1) and A(2) phenotype, respectively, and his ABO expression was negative. FUT1 expression was in the normal range in all three cases. The clinical blood product infusion strategy was formulated according to the genotype and the corresponding immunological subtype, and no significant transfusion-related adverse reactions occurred. Conclusion: Blood group sub-genotypes or aberrant gene expression can lead to ambiguities in serological blood group determination in hematological malignancies patients. ABO genotyping and gene expression analysis can help in this scenario and escort blood product infusion safety.

[The impact of KIT and other concomitant gene mutations on the prognoses of patients with core-binding factor acute myeloid leukemia].

Objective: To study the impact of KIT and other concomitant gene mutations on the prognoses of patients with core-binding factor acute myeloid leukemia (CBF-AML). Methods: A total of 104 newly diagnosed patients with CBF-AML in Hebei Yanda Lu Daopei Hospital from January 2014 to February 2018 were analyzed, and high-throughput gene sequencing for the detection of mutations among 58 genes was executed. Also, the clinical features of KIT mutation-positive CBF-AML (KIT+CBF-AML) patients and the effects of other concomitant gene mutations on the prognoses of patients were also analyzed. Results: A total of 56 cases (53.85%) with KIT mutations were found in 104 CBF-AML patients. Among this, KIT D816 mutation was the most common (32 patients), followed by the N822 mutation (17 patients). Patients with KIT+CBF-AML have a higher proportion of bone marrow blasts at the time of diagnoses and are more likely to have sex chromosome loss. Among the 52 patients with KIT+CBF-AML who were followed up, the allogeneic hematopoietic stem cell transplantation (allo-HSCT) group had a higher overall survival rate (OS) than that of the chemotherapy group (88.9% vs 57.1%, χ(2)=6.076, P<0.05). The event-free survival (EFS) and OS of patients with KIT+CBF-AML with FLT3 mutation were both significantly lower than those of the FLT3 mutation-negative group (EFS: 40.0% vs 72.3%, χ(2)=6.557, P<0.05; OS: 60.0% vs 87.2%, χ(2)=8.305, P<0.05). The OS of the patient with TET2 mutation was lower than that of the TET2 mutation-negative group (50.0% vs 87.5%, χ(2)=4.130, P<0.05). Conclusion: Patients with KIT+CBF-AML with concomitant gene mutations, especially FLT3 and TET2, have poor prognoses, which can be improved by allo-HSCT.