Neutropenia and leukemia development: genetic risk factors and prognosis

Case Report: Characterization of known (c.607G>C) and novel (c.416C>G) ELANE mutations in two Mexican families with congenital neutropenia

The most common causes of congenital neutropenia are mutations in the ELANE (Elastase, Neutrophil Expressed) gene (19p13.3), mostly in exon 5 and the distal portion of exon 4, which result in different clinical phenotypes of neutropenia. Here, we report two pathogenic mutations in ELANE, namely, c.607G>C (p.Gly203Arg) and a novel variant c.416C>G (p.Pro139Arg), found in two Mexican families ascertained via patients with congenital neutropenia who responded positively to the granulocyte colony-stimulating factor (G-CSF) treatment. These findings highlight the usefulness of identifying variants in patients with inborn errors of immunity for early clinical management and the need to rule out mosaicism in noncarrier parents with more than one case in the family.

A Longitudinal Study of Sleep Habits and Leukemia Incidence Among Postmenopausal Women

We sought to assess the relationship between sleep duration, sleep disturbance, and leukemia incidence among postmenopausal women. This study included 130,343 postmenopausal women aged 50-79 years who were enrolled in the Women's Health Initiative (WHI) during 1993-1998. Information on self-reported typical sleep duration and sleep disturbance was obtained by questionnaire at baseline, and sleep disturbance level was defined according to the Women's Health Initiative Insomnia Rating Scale (WHIIRS). WHIIRS scores of 0-4, 5-8, and 9-20 comprised 37.0%, 32.6%, and 30.4% of all women, respectively. After an average of 16.4 years (2,135,109 cumulative person-years) of follow-up, 930 of the participants were identified as having incident leukemia. Compared with women with the lowest level of sleep disturbance (WHIIRS score 0-4), women with higher sleep disturbance levels (WHIIRS scores of 5-8 and 9-20) had 22% (95% confidence interval (CI): 1.04, 1.43) and 18% (95% CI: 1.00, 1.40) excess risks of leukemia, respectively, after multivariable adjustment. A significant dose-response trend was found for the association between sleep disturbance and leukemia risk (P for trend = 0.048). In addition, women with the highest level of sleep disturbance had a higher risk of myeloid leukemia (for WHIIRS score 9-20 vs. WHIIRS score 0-4, hazard ratio = 1.39, CI: 1.05, 1.83). Higher sleep disturbance level was associated with increased risk of leukemia, especially for myeloid leukemia among postmenopausal women.

Estrogens revert neutrophil hyperplasia by inhibiting Hif1α-cMyb pathway in zebrafish myelodysplastic syndromes models

Myelodysplastic syndromes (MDS) are characterized by daunting genetic heterogeneity and a high risk of leukemic transformation, which presents great challenges for clinical treatment. To identify new chemicals for MDS, we screened a panel of FDA-approved drugs and verified the neutrophil hyperplasia inhibiting role of 17β-estradiol (E2, a natural estrogen) in several zebrafish MDS models (pu.1^G242D/G242D, irf8^Δ57Δ/57 and c-myb^hyper). However, the protective mechanism of estrogen in the development of hematological malignancies remains to be explored. Here, analyzing the role of E2 in the development of each hematopoietic lineage, we found that E2 exhibited a specific neutrophil inhibiting function. This neutrophil inhibitory function of E2 is attributed to its down-regulation of c-myb, which leads to accelerated apoptosis and decreased proliferation of neutrophils. We further showed that knockdown of hif1α could mimic the neutrophil inhibiting role of E2, and hif1α overexpression could reverse the protective function of E2. Collectively, our findings highlight the protective role of E2 on MDS by inhibiting hif1α-c-myb pathway, suggesting that E2 is a promising and effective drug for hematopoietic tumors associated with abnormal neutrophil hyperplasia.

Saikosaponin a contributed to CCIN treatment by promoting neutrophil bactericidal activity via activation CBL-dependent ERK pathway

BACKGROUND

Despite granulocyte colony-stimulating factor (GCSF) is widely used in clinical, cancer chemotherapy induced neutropenia (CCIN) infection and infection-related mortality is high for lack of functionally mature neutrophils. Generating functional neutrophils is new therapeutic approaches to reduce CCIN-associated infection and mortality. Saikosaponin a (SSA) is one of the major bioactive components of Radix Bupleuri (RB) and exerts immunoregulatory effects.

PURPOSE

The present study aims to investigate the efficacy and mechanism of SSA in CCIN therapy.

METHODS

SSA was applied both in vitro and in vivo to assess the efficacy of CCIN therapy. The differentiation of neutrophils was measured by Nitroblue tetrazolium (NBT) reduction assay and Giemsa staining assay. The neutrophil differentiation related real-time transcription factors were detected by quantitative PCR (RT-qPCR) and Western Blot. Bacteria killing assay was used to assess the ability of fighting infection. Network pharmacology was employed to explore the mechanism network, and the predicted pathways were validated by Western Blot.

RESULTS

We found that SSA contributed to generate functional mature neutrophils which capable of fighting infection both in vitro and in vivo. Network pharmacology prediction showed 55 pathways were predicted involved in SSA against CCIN. Further validation showed that CBL-ERK1/2 pathway was activated by SSA, which could upregulate PU.1 and CEBPβ expression leading to neutrophil differentiation.

CONCLUSIONS

Our findings suggest a natural regimen SSA regenerates microbicidal neutrophils to effectively reduce CCIN-associated infection via activating CBL-ERK1/2 pathway, providing a rationale for future therapeutic approaches.

Saikosaponin d contributed to cancer chemotherapy induced neutropenia therapy by promoting neutrophil differentiation via activation CBL-dependent ERK pathway

Cancer chemotherapy induced neutropenia (CCIN) is one of the most common toxicity caused by cytotoxic anticancer agents. Despite granulocyte colony-stimulating factor (GCSF) is widely used in clinical practice, the infection and infection-related mortality rate is still high for lack of functionally mature neutrophils. Saikosaponin d (SSD) is one of the major bioactive constituents of Radix Bupleuri (RB), which exerts immune-modulatory properties. We explored the function of SSD in CCIN therapy, we found that SSD contributed to generate functional mature neutrophils which capable of fighting infection both in vitro and in vivo. Network pharmacology was employed to explore the mechanism, 61 signal pathways might play an important role in CCIN treatment. Western Blot was employed to further confirm the potential pathway involved. We found CBL-ERK1/2 pathway was activated by SSD, followed by upregulating PU.1 and CEBPβ expression and leading to neutrophil differentiation. Our findings suggest a natural regimen SSD which could regenerate microbicidal neutrophils to effectively reduce CCIN-associated infection via activating CBL-ERK1/2, providing a rationale for future therapeutic approaches.

Essential thrombocythemia: a hemostatic view of thrombogenic risk factors and prognosis

Essential thrombocythemia (ET) is a classical myeloproliferative neoplasm that is susceptible to hypercoagulable state due to impaired hemostatic system, so that thrombotic complications are the leading cause of mortality in ET patients. The content used in this article has been obtained by the PubMed database and Google Scholar search engine from English-language articles (2000-2019) using the following keywords: "Essential thrombocythemia," "Thrombosis," "Risk factors" and "Hemostasis. In this neoplasm, the count and activity of cells such as platelets, leukocytes, endothelial cells, as well as erythrocytes are increased, which can increase the risk of thrombosis through rising intercellular interactions, expression of surface markers, and stimulation of platelet aggregation. In addition to these factors, genetic polymorphisms in hematopoietic stem cells (HSCs), including mutations in JAK2, CALR, MPL, or genetic abnormalities in other genes associated with the hemostatic system may be associated with increased risk of thrombotic events. Moreover, disruption of coagulant factors can pave the way for thrombogeneration. Therefore, the identification of markers related to cell activation, genetic abnormalities, or alternation in the coagulant system can be used together as diagnostic and prognostic markers for the occurrence of thrombosis among ET patients. Thus, because thrombotic complications are the main factors of mortality in ET patients, a hemostatic viewpoint and risk assessment of cellular, genetic, and coagulation factors can have prognostic value and contribute to the choice of effective treatment and prevention of thrombosis.

PEAR1 polymorphisms as a prognostic factor in hemostasis and cardiovascular diseases

Platelet Endothelial Aggregation Receptor (PEAR1), as a platelet receptor, plays a vital role in hemostasis. This receptor, by its extracellular part, causes platelet adhesion and consequently initiates platelet aggregation. Dysfunction of PEAR1 can disrupt platelet aggregation in patients with cardiovascular diseases (CVDs). The content used in this paper has been taken from English language articles (2005-2020) retrieved from Pubmed database and Google scholar search engine using "Cardiovascular Disease", "PEAR1", "Polymorphism", and "Platelet Aggregation" keywords. Some PEAR1 polymorphisms can disrupt homeostasis and interfere with the function mechanism of cardiac drugs. Since polymorphisms in this gene affect platelet function and the platelet aggregation process, PEAR1 could be further studied in the future as an essential factor in controlling the treatment process of patients with cardiovascular diseases. PEAR1 polymorphisms through disruption of the platelet aggregation process can be a risk factor in patients with CVDs. Therefore, controlling patients through genetic testing and the evaluation of PEAR1 polymorphisms can help improve the treatment process of patients. According to the studies on the PEAR1 gene and the effect of different polymorphisms on some crucial issues in CVDs patients (changes in platelet activity), it is clear that if there is a significant relationship between polymorphisms and CVDs, they can be used as prognostic and diagnostic markers. This study aims to evaluate the prognosis and drug treatment of the PEAR1 gene in CVDs patients.

Deep vein thrombosis: a less noticed complication in hematologic malignancies and immunologic disorders

Deep vein thrombosis (DVT) is a common complication in hematologic malignancies and immunologic disorders that coagulation and inflammatory factors play a crucial role in its occurrence. The content used in this article has been obtained by PubMed database and Google Scholar search engine of English-language articles (1980-2019) using the "Deep vein thrombosis," "Hematologic malignancies," "Immunologic disorders" and "Treatment." Increased levels of coagulation factors, the presence of genetic disorders, or the use of thrombotic drugs that stimulate coagulation processes are risk factors for the development of DVT in patients with hematologic malignancies. Inflammatory and auto-anti-inflammatory factors, along with coagulant factors, play an essential role in the formation of venous thrombosis in patients with immunological disorders by increasing the recruitment of inflammatory cells and adhesion molecules. Therefore, anti-coagulants in hematologic malignancies and immunosuppressants in immune disorders can reduce the risk of developing DVT by reducing thrombotic and inflammatory activity. Considering the increased risk of DVT due to impaired coagulation and inflammation processes, analysis of coagulation and inflammatory factors have prognostic values in patients with immunologic deficiencies and hematologic malignancies. Evaluation of these factors as diagnostic and prognostic biomarkers in the prediction of thrombotic events could be beneficial in implementing effective treatment strategies for DVT.