Page 93 - Haematologica April 2020

ARHGEF12 in erythropoiesis of chemotherapy patients
ber of studies have reported that p38 MAPK is involved in erythroid differentiation,39-41 yet the role of p38 MAPK in stress erythropoiesis is still poorly understood. P38α regu- lates erythroblast enucleation in a cell-autonomous man- ner in vivo during fetal and anemic stress erythropoiesis.42 Remarkably, loss of p38α leads to downregulation of p21Cip1, and decreased activation of the p21Cip1 inacti- vates Rb, both of which are critical regulators of erythrob- last enucleation. Hu et al. suggested P38α could act as a molecular brake to limit over-active erythropoiesis in response to stress-relief of this molecular brake by inhibit- ing P38-enhanced stress erythropoiesis and accelerated recovery from anemia.43 Our observed association of a down-regulated erythroid p38 phosphorylation in patients with the ARHGEF12 polymorphism who need multiple RBC transfusions to overcome chemotherapy-induced anemia also supports the involvement of such a pathway. Pharmacological activation of wild-type p53 is a logical therapeutic strategy for leukemia where the p53 pathway could be down-regulated by abnormalities in p53-regulato- ry proteins.44 It has been reported that p38 kinase can pos- itively regulate p53, and activation of p38 not only pro- motes erythropoiesis, but also potentially maintains a higher level of p53 in cancer cells, which can be a dual ben- efit for cancer patients who carry wild-type p53 alleles.
Several reported GWAS studies related to hematologic traits failed to find a correlation between ARHGEF12 and erythroid phenotypes45,46 in normal populations, which may suggest there are functional redundancies to the ARHGEF12-RhoA-p38 pathway in homeostatic erythro- poiesis. Suboptimal level of guanine nucleotide exchange activity may be compensated by down-regulated RhoA negative regulator, GTPase-activating proteins, or by other guanine nucleotide exchange factors, such as ARHGEF3, which was shown to be important for erythropoiesis through RhoA in a zebrafish model.47 Our GWAS results draw a clear association between ARHGEF12 at rs10892563 with erythrocyte regeneration under chemotherapy stress, suggesting that this gene/SNP status may be considered a biomarker to predict severity of chemotherapy-induced anemia among the patients.
In addition to the erythropoiesis differentiation mecha- nism, genes expressed in HSPC can also be associated with chemotherapy-associated anemia. To this end, we analyzed the primary gene list with expression patterns in the CD34+ cell population before erythroid differentiation with the same database as we did for the erythrocyte-spe- cific genes. Among the genes highly expressed in HSPC, four of the top five have known functional connection with erythropoiesis (Figure 1C). While a correlation analy- sis between RBC transfusion and severity of neutropenia reveals that RBC transfusions had no significant correla- tion with neutropenia, there was a significance in correla- tion with thrombocytopenia (Online Supplymentary Figure S7). This suggests that it is possible that effects on HSPC such as megakaryocyte-erythroid progenitors could be a contributing factor to chemotherapy-induced anemia.
Combining our patient SNPs and phenotype observa- tions, biochemical analyses of patient samples, and human and murine cells, together with the zebrafish genetic model characterizations, our studies unveil a novel SNP related to chemotherapy-induced anemia in ARHGEF12 and the associated signaling pathway. These findings will be useful for future consideration of strate- gies to overcome the chemotherapy-induced anemia in some ALL patients.
Acknowledgments
The authors would like to thank the staff of Shanghai Institute of Hematology for their assistance with zebrafish husbandry, par- ticularly Yi Chen. We thank Yongjuan Zhang for the SNP link- age disequilibrium analysis and Professor Xiaojian Sun for help- ful discussions.
Funding
This research was supported by grants from the National Natural Science Foundation of China (n. 81270623 ), The National Key R&D Program of China, Stem Cell and Translation Research (n. 2016YFA0102000) and The fourth round of Three-Year Public Health Action Plan (2015-2017) (GWIV-25). This research was also supported by the National Natural Science Foundation of China (No. 81900114).
References
1. Sun XJ, Xu PF, Zhou T, et al. Genome-Wide Survey and Developmental Expression Mapping of Zebrafish SET Domain- Containing Genes. PLoS One. 2008;3(1): e1499.
2. Jao LE, Wente SR, Chen W. Efficient multi- plex biallelic zebrafish genome editing using a CRISPR nuclease system. Proc Natl Acad Sci U S A. 2013;110(34):13904–13909.
3. Novershtern N, Subramanian A, Lawton LN, et al. Densely interconnected transcrip- tional circuits control cell states in human hematopoiesis. Cell. 2011;144(2):296–309.
4. Ikuta T, Sellak H, Odo N, Adekile AD, Gaensler KML. Nitric Oxide-cGMP Signaling Stimulates Erythropoiesis through Multiple Lineage- Specific Transcription Factors : Clinical Implications and a Novel Target for Erythropoiesis. Plos One. 2016;11(1):e0144561.
5. Chen C, Lodish HF. Global analysis of induced transcription factors and cofactors
identifies Tfdp2 as an essential coregulator during terminal erythropoiesis. Exp Hematol. 2014;42(6):464–476.
6. Henneberry AL, Wistow G, Mcmaster CR. Cloning, genomic organization, and charac- terization of a human cholinephosphotrans- ferase. J Biol Chem. 2000;8(4):29808–29815.
7. Cocco L, Manzoli L, Faenza I, et al. Advances in Biological Regulation Modulation of nuclear PI-PLCbeta1 during cell differentiation. Adv Biol Regul. 2016;60:1–5.
8. Ferguson PJ, Chen S, Tayeh MK, et al. Homozygous mutations in LPIN2 are responsible for the syndrome of chronic recurrent multifocal osteomyelitis and con- genital dyserythropoietic anaemia (Majeed syndrome). J Med Genet. 2005;42(7):551– 557.
9. Shih YP, Sun P, Wang A, Lo SH. Tensin1 pos- itively regulates RhoA activity through its interaction with DLC1. Biochim Biophys Acta - Mol Cell Res. 2015;1853(12):3258– 3265.
10. Konstantinidis DG, Giger KM, Risinger M,
et al. Cytokinesis failure in RhoA-deficient mouse erythroblasts involves actomyosin and midbody dysregulation and triggers p53 activation. Blood. 2015;126(12):1473–1482.
11. Coste I, Gauchat JF, Wilson A, et al. Unavailability of CD147 leads to selective erythrocyte trapping in the spleen. Blood. 2001;97(12):3984–3988.
12. Ma C, Wang J, Fan L, Guo Y. Inhibition of CD147 expression promotes chemosensitiv- ity in HNSCC cells by deactivating MAPK/ERK signaling pathway. Exp Mol Pathol. 2017;102(1):59–64.
13. Dorn I, Meyer G, Lindner U, Driller B, Schlenke P. The influence of extracellular matrix proteins and mesenchymal stem cells on erythropoietic cell maturation. Vox Sang. 2011;101(1):65–76.
14. Abed M, Balasaheb S, Towhid ST, Daniel C, Amann K, Lang F. Adhesion of Annexin 7 Deficient Erythrocytes to Endothelial Cells. PLoS One. 2013;8(2):1–10.
15. Hayette S, Dhermy D, dos Santos ME, et al. A deletional frameshift mutation in protein 4.2 gene (allele 4.2 Lisboa) associated with
haematologica | 2020; 105(4)
935