Unique Familial MLL(KMT2A)-Rearranged Precursor B-Cell Infant Acute Lymphoblastic Leukemia in Non-twin Siblings

Nestin Regulates Keap1-Nrf2-HO-1-Mediated Antioxidant Responses during Stress and Malignant Hematopoiesis

Objective

To investigate the role of nestin in regulating Keap1-nuclear factor erythroid-2-related factor 2 (Nrf2)-heme oxygenase-1-(HO-1-) mediated antioxidant responses in stress and malignant hematopoiesis.

Methods

The mRNA of peripheral blood mononuclear cells was extracted from 20 leukemia patients and 20 healthy people who were hospitalized in the Hematology Department of our hospital from September 2020 to December 2021, and the mRNA levels of nestin, Keap1, Nrf2, and HO-1 were detected by real-time- (RT-) PCR.

Results

Compared with healthy controls, the mRNA of nestin, Keap1, Nrf2, and HO-1 in peripheral blood mononuclear cells of leukemia patients was significantly upregulated.

Conclusion

The occurrence and development of leukemia are closely related to nestin regulating Keap1-Nrf2-Ho-1 signal pathway. Research Significance. This study determined the effect of nestin on the biological behavior of leukemia cells and its possible mechanism and confirmed that nestin may be a marker of tumor and tumor blood vessels.

Risk assessment of FLT3 and PAX5 variants in B-acute lymphoblastic leukemia: a case-control study in a Pakistani cohort

AIMS

B-cell acute lymphoblastic leukemia (B-ALL) is amongst the most prevalent cancers of children in Pakistan. Genetic variations in FLT3 are associated with auto-phosphorylation of kinase domain that leads to increased proliferation of blast cells. Paired box family of transcription factor (PAX5) plays a critical role in commitment and differentiation of B-cells. Variations in PAX5 are associated with the risk of B-ALL. We aimed to analyze the association of FLT3 and PAX5 polymorphisms with B cell leukemia in Pakistani cohort.

METHODS

We collected 155 B-ALL subject and 155 control blood samples. For analysis, genotyping was done by tetra ARMS-PCR. SPSS was used to check the association of demographic factors of SNPs present in the population with the risk of B-ALL.

RESULTS

Risk allele frequency A at locus 13q12.2 (rs35958982, FLT3) was conspicuous and showed positive association (OR = 2.30, CI [1.20–4.50], P = 0.005) but genotype frequency (OR = 3.67, CI [0.75–18.10], P = 0.088) failed to show any association with the disease. At locus 9p13.2 (rs3780135, PAX5), the risk allele frequency was significantly higher in B-ALL subjects than ancestral allele frequency (OR = 2.17, CI [1.37–3.43], P = 0.000). Genotype frequency analysis of rs3780135 polymorphism exhibited the protective effect (OR = 0.55, CI [0.72–1.83], P = 0.029). At locus 13q12.2 (rs12430881, FLT3), the minor allele frequency G (OR = 1.15, CI [1.37–3.43], P = 0.043) and genotype frequency (OR = 2.52, P = 0.006) reached significance as showed p < 0.05.

CONCLUSION

In the present study, a strong risk of B-cell acute lymphoblastic leukemia was associated with rs35958982 and rs12430881 polymorphisms. However, rs3780135 polymorphism showed the protective effect. Additionally, other demographic factors like family history, smoking and consanguinity were also found to be important in risk assessment. We anticipate that the information from genetic variations in this study can aid in therapeutic approach in the future.

A novel deletion mutation in KMT2A identified in a child with ID/DD and blood eosinophilia

Background

The KMT2A gene encoded lysine methyltransferase plays an essential role in regulating gene expression during early development and hematopoiesis. To date, 92 different mutations of KMT2A have been curated in the human gene mutation database (HGMD), resulting in Wiedemann-Steiner syndrome (WDSTS) and intellectual disability (ID)/developmental delay (DD).

Case presentation

In this report, we present a de novo heterozygous deletion mutation [c.74delG; p. (Gly26Alafs*2)] in the KMT2A gene, which was identified by trio-based whole exome sequencing from a 5.5-year-old boy with ID/DD, stereotypic hand movements and blood eosinophilia. Many deleterious germline mutations of KMT2A have been documented to affect development of central nervous system, oral and craniofacial tissues, but not blood eosinophils.

Conclusions

This is the first report of a rare case with ID/DD as well as eosinophilia, resulting from a previously undescribed null mutation of KMT2A. Our findings expand the phenotypical spectrum in affected individuals with KMT2A mutations, and may shed some insight into the role of KMT2A in eosinophil metabolism.

Electronic supplementary material

The online version of this article (10.1186/s12881-019-0776-0) contains supplementary material, which is available to authorized users.

Relatively favorable prognosis for MLL-rearranged childhood acute leukemia with reciprocal translocations

BACKGROUND

Mixed-lineage leukemia (MLL) with multifarious partner genes leads to aggressive leukemia with dismal outcomes.

METHODS

Using panel-based targeted sequencing, we examined 90 cases with MLL-rearranged (MLL-r) childhood acute leukemia, including 55 with acute lymphoblastic leukemia (ALL) and 35 with acute myeloid leukemia (AML).

RESULTS

MLL breakpoints and complete rearrangements were identified. A total of 37.8% (34/90) of patients displayed a single direct MLL fusion gene, 15.6% (14/90) carried a single reciprocal fusion, and 27.8% (25/90) had both reciprocal MLL fusion alleles. The remaining 17 MLL-r cases exhibited complex translocations with homozygous disruptions on chromosome 11 or two breakpoints on the same MLL allele with a deletion of functional regions. A total of 77 patients (45 ALL and 32 AML) received chemotherapy with a median follow-up of 2.5 years. Unexpectedly, we identified children with reciprocal MLL fusions who exhibited relatively favorable outcomes compared with those in children with complex translocations or a single direct MLL fusion allele (66.1% vs. 24.6% and 27.6%, P = 0.001). Reciprocal MLL fusion may be functionally rescued by a partially truncated MLL protein.

CONCLUSION

Comprehensive MLL-r analysis by targeted next-generation sequencing can provide detailed molecular information and is helpful for precise stratified treatment and clinical prognosis determination.