scholarly journals Scaffold-mediated CRISPR-Cas9 delivery system for acute myeloid leukemia therapy

2021 ◽  
Vol 7 (21) ◽  
pp. eabg3217
Author(s):  
Tzu-Chieh Ho ◽  
Hye Sung Kim ◽  
Yumei Chen ◽  
Yamin Li ◽  
Mark W. LaMere ◽  
...  

Leukemia stem cells (LSCs) sustain the disease and contribute to relapse in acute myeloid leukemia (AML). Therapies that ablate LSCs may increase the chance of eliminating this cancer in patients. To this end, we used a bioreducible lipidoid-encapsulated Cas9/single guide RNA (sgRNA) ribonucleoprotein [lipidoid nanoparticle (LNP)–Cas9 RNP] to target the critical gene interleukin-1 receptor accessory protein (IL1RAP) in human LSCs. To enhance LSC targeting, we loaded LNP-Cas9 RNP and the chemokine CXCL12α onto mesenchymal stem cell membrane–coated nanofibril (MSCM-NF) scaffolds mimicking the bone marrow microenvironment. In vitro, CXCL12α release induced migration of LSCs to the scaffolds, and LNP-Cas9 RNP induced efficient gene editing. IL1RAP knockout reduced LSC colony-forming capacity and leukemic burden. Scaffold-based delivery increased the retention time of LNP-Cas9 in the bone marrow cavity. Overall, sustained local delivery of Cas9/IL1RAP sgRNA via CXCL12α-loaded LNP/MSCM-NF scaffolds provides an effective strategy for attenuating LSC growth to improve AML therapy.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4697-4697
Author(s):  
Olga Blau ◽  
Wolf-Karsten Hofmann ◽  
Claudia D Baldus ◽  
Gundula Thiel ◽  
Florian Nolte ◽  
...  

Abstract Abstract 4697 Bone marrow mesenchymal stroma cells (BMSC) are key components of the hematopoietic microenvironment. BMSC from patients with acute myeloid leukemia (AML) and myelodisplasic syndrome (MDS) display functional and quantitative alterations. To gain insight into these questions, we carried out cytogenetic analyses, FISH, FLT3 and NPM1 mutation examinations of both hematopoietic (HC) and BMSC derived from 53 AML and 54 MDS patients and 35 healthy donors after in vitro culture expansion. Clonal chromosomal aberrations were detectable in BMSC of 12% of patients. Using FISH we have assume that cytogenetic markers in BMSC were always distinct as the aberrations in HC from the same individual. 17% and 12% of AML patients showed FLT3 and NPM1 mutations in HC, respectively. In BMSC, we could not detect mutations of NPM1 and FLT3, independent from the mutation status of HC. For control analysis, BMSC cultures from 35 healthy donors were prepared under the same conditions. BMSC from healthy donors did show normal diploid karyotypes and absence of specific DNA-mutations of NPM1 and FLT3. Our data indicate that BMSC from MDS and AML patients are not a part of malignant clone and characterized by genetic aberrations. Lack of aberrations as detected in HC and appearance of novel clonal rearrangements in BMSC may suggest enhanced genetic susceptibility and potential involvement of BMSC in the pathogenesis of MDS and AML. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1425-1425 ◽  
Author(s):  
Kim R Kampen ◽  
Arja ter Elst ◽  
André B Mulder ◽  
Megan E Baldwin ◽  
Klupacs Robert ◽  
...  

Abstract Abstract 1425 Previously, it was demonstrated that exogenous addition of vascular endothelial growth factor C (VEGFC) increased the leukemic cell viability, reduced apoptosis via activation of Bcl-2, and decreased chemotherapy induced apoptosis via its receptor FLT-4 (Further revert to as VEGFR3) (Dias et al. Blood 2002). Furthermore, it was shown that VEGFC promotes angiogenesis by induction of COX-2 through VEGFR3 activation in THP-1 cells (Chien et al. Carcinogenesis 2005). We have previously found that endogenous VEGFC expression is associated with decreased drug responsiveness in childhood acute myeloid leukemia (AML), both in vitro as well as in vivo (de Jonge et al. Clinical Cancer Research 2008). In addition, high VEGFC mRNA expression is strongly associated with reduced complete remission and overall survival in adult as well as pediatric AML (de Jonge et al. Blood 2010). It was thought that the leukemic blast population is organized as a hierarchy, whereby leukemia initiating cells (LICs) reside at the top of this hierarchy, and it is only these cells that have the capacity to engraft in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice. The LIC is thought to be enriched in the CD34+ leukemic cell fraction and is shown to expand in vitro using a myeloid cytokine mix of IL-3, TPO, and G-CSF in colony forming cell (CFC) assays and long-term culture-initiating cell (LTC-IC) assays (Guan et al. Exp. Hematol. 2002, van Gosliga et al. Exp. Hematol. 2007). Moreover, LTC-IC assays performed in limiting dilution detect the in vitro outgrowth potential of stem-like cells that reside underneath the stromal cell layer. In this study, we set out to investigate the potential of anti-VEGFC treatment as an inhibitor of the outgrowth of LICs within the CD34+ fraction of primary AML samples. First, we determined the possibility of an autocrine loop for VEGFC in AML. Pediatric AML cell (n=7) derived VEGFC levels were found to be 1.4-fold increased (P =.008) compared to secreted VEGFC levels from normal bone marrow (NBM) cells (n=4). Pediatric AML blast cells showed KDR (further revert to as VEGFR2) membrane expression in 44 out of 50 patient samples (varying 8–99% of the total blast population), whereas on NBM cells VEGFR2 expression was below 5%. VEGFR3 expression was below 5% on both leukemic blasts and NBM cells. We evaluated the effect of anti-VEGFC (VGX-100, kindly provided by Vegenics, used at a concentration of 30 μg/ml) treatment on the CD34+ isolated compartment of pediatric AML bone marrow samples. Anti-VEGFC treatment reduced the outgrowth potential of AML derived CD34+ cells (n=2) with >25% in CFC assays. Interestingly, morphological analysis revealed a 3-fold enhanced formation of macrophages. LTC-IC assays demonstrated a (15% to 50%) decrease in the long-term growth of CD34+ isolated AML cells in 3 out of 4 patient samples. Morphological characterization of the suspension cells suggested a shift in development along the myelomonocytic lineage after two weeks of anti-VEGFC treatment. With FACS analysis, these cells showed a higher number of cells stained positive for CD11b, and CD14, and lower numbers where positive for CD34. Anti-VEGFC treated LTC-IC assays in limiting dilution demonstrated a (44% and 74%) reduction in the outgrowth potential of long-term cultured CD34+ isolated AML cells and blocked the erythroid colony formation in 2 out of 3 patient samples. Anti-VEGFC treatment did not have an effect on the outgrowth of CD34+ sorted NBM cells in the various assays (n=2). In conclusion, anti-VEGFC treatment of the CD34+ isolated fraction from primary pediatric AML samples showed a reduction of AML outgrowth. Differentiating cells are skewed to the myelomonocytic lineage upon anti-VEGFC treatment. We hypothesize that deprivation of VEGFC in primary CD34+ AML cell cultures results in enhanced leukemic cell death and abates an important proliferation signal for AML cells. Yet, further investigations are warranted.Figure 1.Skewing of LTC-IC assay suspension cells towards the myelomonocytic lineage upon anti-VEGFC treatment. MGG stained cytospins of suspension cells of the LTC-IC co-culture obtained during demi-depopulation at week 2.Figure 1. Skewing of LTC-IC assay suspension cells towards the myelomonocytic lineage upon anti-VEGFC treatment. MGG stained cytospins of suspension cells of the LTC-IC co-culture obtained during demi-depopulation at week 2. Disclosures: Baldwin: Circadian Technologies Limited: Employment. Robert:Circadian Technologies Limited: Employment, Membership on an entity's Board of Directors or advisory committees.


1997 ◽  
Vol 21 (6) ◽  
pp. 519-527 ◽  
Author(s):  
Meir Wetzler ◽  
Razelle Kurzrock ◽  
Zeev Estrov ◽  
Steve Barone ◽  
Elihu Estey ◽  
...  

Blood ◽  
1982 ◽  
Vol 59 (4) ◽  
pp. 816-821
Author(s):  
K Swart ◽  
A Hagemeijer ◽  
B Lowenberg

Bone marrow or blood of patients with acute myeloid leukemia was subjected to cell separation and the cells investigated for in vitro colony growth. Discontinuous albumin density gradient centrifugation and depletion of E-rosette-forming cells resulted in purified fractions of acute myeloid leukemia cells. From these fractions, growth of large leukemic colonies was obtained in the PHA-leukocyte feeder (PHA-LF) colony technique in 12 of 14 patients. The standard double agar layer techniques with a leukocyte feeder for granulocyte-macrophage colony forming cells (GM-CFC) supported colony formation in only four cases. The PHA-LF leukemic colony-forming cells (CFC) were found to be of low buoyant density (always less than or equal to 1.062 g.ml-1) when compared to normal marrow GM-CFC (peak at 1.065 g.ml-1). The density profile of PHA-LF CFC paralleled the distribution of the nucleated cells in 8 cases, but in 4 patients, the cFC peak was found at a distinctly lower density; this suggested that a specific leukemic subpopulation had a colony-forming capacity. In three of the four patients with colony growth in the double layer agar technique, it was evident that these CFC had density properties different from those of PHA-LF CFC. These findings suggest that cells giving rise to large colonies in the PHA-LF and double layer agar assays represent distinct leukemic subpopulations.


Cancers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1663 ◽  
Author(s):  
Arne Velthaus ◽  
Kerstin Cornils ◽  
Jan K. Hennigs ◽  
Saskia Grüb ◽  
Hauke Stamm ◽  
...  

Leukemia-initiating cells reside within the bone marrow in specialized niches where they undergo complex interactions with their surrounding stromal cells. We have identified the actin-binding protein Plastin-3 (PLS3) as potential player within the leukemic bone marrow niche and investigated its functional role in acute myeloid leukemia. High expression of PLS3 was associated with a poor overall and event-free survival for AML patients. These findings were supported by functional in vitro and in vivo experiments. AML cells with a PLS3 knockdown showed significantly reduced colony numbers in vitro while the PLS3 overexpression variants resulted in significantly enhanced colony numbers compared to their respective controls. Furthermore, the survival of NSG mice transplanted with the PLS3 knockdown cells showed a significantly prolonged survival in comparison to mice transplanted with the control AML cells. Further studies should focus on the underlying leukemia-promoting mechanisms and investigate PLS3 as therapeutic target.


Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5040-5040
Author(s):  
Bing Xu ◽  
Rongwei Li ◽  
Huijuan Dong ◽  
Feili Chen ◽  
Yuejian Liu ◽  
...  

Abstract Background Disulfiram(DS), an old drug clinically used for alcoholism, was reported to have antitumor effects, recent studies have found that Copper(Cu) can significantly enhance the DS-induced cell death in vitro in a variety of tumor cells. Our previous studies also demonstrated that disulfiram/copper (DS/Cu) couldtarget human leukemia cell lines(like KG1α,Molt4) through the activation of JNK, in vitro. However, there is few report about the ability of DS/Cu in killing cancer cells in vivo. Aims This study aims to explore the effect of DS/Cu on acute myeloid leukemia cell line KG1αin vivo and clarify the underlining mechanism. Methods 6-8 week old female NOD/SCID mice were sublethally irradiated with 2Gy X-ray the day before transplantation, followed by intravenous injection of KG1α cells (1×107 cells) suspended in 0.2 mL of PBS. 5 weeks after transplantation mice were randomly divided into three treatment groups: vehicle (0.9% saline), a combination of DS and Cu daily for 2 weeks, Ara-C alone twice before killing. Mice were sacrificed after 2 weeks treatment with tissues of spleen, liver, bone marrow being observed using histopathology method to detect the invasion of leukemia. The DS/Cu-induced p-c-jun activation was also examined by western blot using tissues of spleen, liver, bone marrow. Statistical analysis was carried out with one-way ANOVA to assess statistical significance (*p < 0.05). Results 4 weeks after transplantation, mice were dispirited with low appetite, down-bent gait, wrinkled fur, slow move, just like suffered from leukemia. What’s more, immature blasts like morphology similar to KG1α were found in the peripheral blood of the mice(11%±3.41). All the mice were sacrificed after 2 weeks treatment, mice in control group were observed with slightly larger spleen and liver with the morphology of invasion of leukemia such as a granular appearance than the other two groups. Histopathology examination showed that leukemia cells infiltrate liver, spleen and bone marrow, and the immunohistochemistry examination found that the leukemia cells in spleen, liver and bone marrow expressed human specific antigen CD45 with the highest expression level in the control group. Moreover, solid tumor could be observed in the peritoneal cavity of two mice in the control group with expression of human specific antigen CD45detected by immunohistochemistry examination. Western blot in this study showed DS/Cu complex induced phosphorylation of c-Jun expression in the spleen, liver and bone marrow. Conclusion DS/Cu complex could effectively target the acute myeloid leukemia cells in the acute leukemia NOD/SCID mice while inhibiting the invasion of leukemia to some extent, and the activation of JNK might play a functional role in DS/Cu mediated antileukemic effects. Disclosures: No relevant conflicts of interest to declare.


2020 ◽  
Vol 4 (13) ◽  
pp. 3000-3010 ◽  
Author(s):  
Jan Habbel ◽  
Lucas Arnold ◽  
Yiyang Chen ◽  
Michael Möllmann ◽  
Kirsten Bruderek ◽  
...  

Abstract Acute myeloid leukemia (AML) is characterized by a high relapse rate and dismal long-term overall survival which is related to persistence of leukemia-initiating cells in their niche. Different animal models of myeloid malignancies reveal how neoplastic cells alter the structural and functional characteristics of the hematopoietic stem cell niche to reinforce malignancy. Understanding and disruption of the microenvironmental interactions with AML cells are a vital need. Malignant niches frequently go along with inflammatory responses, but their impact on cancerogenesis often remains unexplored. Here, we uncovered an aberrant production of inflammatory cytokines in untreated AML bone marrow that was proved to promote the proliferation of leukemia cells. This inflammatory response induced an activation of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway in AML blasts as well as bone marrow stromal cells that also fostered leukemia proliferation. Inhibition of JAK/STAT signaling using the selective JAK1/2 inhibitor ruxolitinib resulted in significant antileukemic activity in AML in vitro which is mediated through both cell-autonomous and microenvironment-mediated mechanisms. However, in a xenograft transplantation model, monotherapy with ruxolitinib did not achieve substantial antileukemic activity, possibly suggesting a complementary function of JAK1/2 inhibition in AML.


Blood ◽  
1979 ◽  
Vol 54 (2) ◽  
pp. 530-533
Author(s):  
JH McCarthy ◽  
JR Sullivan ◽  
B Ungar ◽  
D Metcalf

In vitro agar culture patterns of bone marrow cells in acute myeloid leukemia may show several growth patterns, including cultures where no colonies or clusters develop, cultures with varying numbers of clusters and no colonies, or colony and cluster formation with an extremely high ratio of clusters to colonies. Twelve cases of carcinoma of the lung are described, of which two show an in vitro growth pattern of cluster formation alone, characteristic of that seen in acute myeloid leukemia. The remaining ten patients showed slightly reduced colony numbers compared to normal.


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