xenograft mice
Recently Published Documents


TOTAL DOCUMENTS

178
(FIVE YEARS 92)

H-INDEX

16
(FIVE YEARS 5)

2021 ◽  
Author(s):  
Feiliang Zhong ◽  
Tingting Chen ◽  
Jia Liu ◽  
Ying Wang ◽  
Mingdong Yao ◽  
...  

Abstract Background: Melanoma is the most serious skin cancer with gradually increased incidence and poor prognosis mainly as the result of cancer stem cell (CSC) expansion and drug resistance. Some studies have suggested that dysregulated cholesterol homeostasis increasing tumorigenicity and metastasis in cancers. In the present study, our objective was to elucidate the contribution of 24-Dehydrocholesterol reductase (DHCR24) towards melanoma progression and drug resistance.Methods: Immunohistochemistry and HE staining were performed for determing the expression of DHCR24 in melanoma patients, lentivirus perturbation and functional assays were used to evaluate the ability of turmorigenesis of DHCR24 altered melanoma cells and melanoma stem-like cells. RNA sequencing (RNA-seq) and targeted metabolomics were carried out for identifying metabolites which contributes melanoma stem-like cell expansion and vemurafenib treatment resistance.Results: DHCR24 was over-expressed in melanoma patients while knockdown of DHCR24 blocked melanoma cells in S phase and lead to significant inhibition in proliferation and migration. Meanwhile, forced expression of DHCR24 promotes the growth of melanoma cells in xenograft mice. We further demonstrated that DHCR24 promotes the proliferation of melanoma stem-like cell populations by activating Rap1/AKT signaling and result in accumulation of cellular 27-Hydroxycholesterol (27-HC) contents. Next, we validated that both CYP27A1 and 27-HC administration contributed to melanoma stem-like cells formation and vemurafenib resistance through AKT-308/309 phosphorylation. Conclusions: Our data confirmed the oncogenic role of DHCR24 in melanoma stem-like cells proliferation and vemurafenib resistance by regulating 27-HC. These findings established the basis of targeting DHCR24 as a potential therapeutic target for advanced melanoma.


Cancers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 5866
Author(s):  
Minhua Chen ◽  
Yutong Li ◽  
Yu Wu ◽  
Siqi Xie ◽  
Jie Ma ◽  
...  

Natural killer (NK) cells have shown great therapeutic potential against a wide range of cancers due to their pan-specific target recognition. Numerous reports indicate that NK cell immunotherapy is an effective therapeutic approach for treating hematological malignancies, but shows limited effects against solid tumors. In this study, several models of ovarian cancer (OC) were used to test the anti-cancer effects of NK cells derived from human peripheral blood mononuclear cells and expanded using a feeder cell-free expansion system (eNKs). The results show that eNKs exhibit potent inhibitory activity on tumor growth in different ovarian cancer xenograft mice (i.e., solid tumors, abdominal metastatic tumors, and ascites), importantly, in a dose-dependent manner. Moreover, adoptive transfer of eNKs resulted in significant reduction in ascites formation in OC peritoneal tumor models, and especially in reducing intraperitoneal ascites. We found that eNKs could migrate to the tumor site, retain their activity, and proliferate to maintain high cell counts in cutaneous xenograft mice. In addition, when increased the infusion with a high dose of 12 × 107 cells/mouse, Graft-versus-host disease could be induced by eNK. These data show that eNK cell immunotherapy could be a promising treatment strategy for ovarian cancers, including solid tumors and ascites.


PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259563
Author(s):  
Yi-Fan Xu ◽  
Xiaohui Xu ◽  
Kritisha Bhandari ◽  
Amy Gin ◽  
Chinthalapally V. Rao ◽  
...  

microRNAs (miRNA) in extracellular vesicles (EVs) have been investigated as potential biomarkers for pancreatic ductal adenocarcinoma (PDAC). However, a mixed population of EVs is often obtained using conventional exosome isolation methods for biomarker development. EVs are derived from different cellular processes and present in various sizes, therefore miRNA expression among them is undoubtedly different. We developed a simple protocol utilizing sequential filtration and ultracentrifugation to separate PDAC EVs into three groups, one with an average diameter of more than 220 nm, named operational 3 (OP3); one with average diameters between 100–220 nm, named operational 2 (OP2); and another with average diameters around 100 nm, named operational 1 (OP1)). EVs were isolated from conditioned cell culture media and plasma of human PDAC xenograft mice and early stage PDAC patients, and verified by nanoparticle tracking, western blot, and electronic microscopy. We demonstrate that exosome specific markers are only enriched in the OP1 group. qRT-PCR analysis of miRNA expression in EVs from PDAC cells revealed that expression of miR-196a and miR-1246, two previously identified miRNAs highly enriched in PDAC cell-derived exosomes, is significantly elevated in the OP1 group relative to the other EV groups. This was confirmed using plasma EVs from PDAC xenograft mice and patients with localized PDAC. Our results indicate that OP1 can be utilized for the identification of circulating EV miRNA signatures as potential biomarkers for PDAC.


Author(s):  
Marion Arnaud ◽  
Johanna Chiffelle ◽  
Raphael Genolet ◽  
Blanca Navarro Rodrigo ◽  
Marta A. S. Perez ◽  
...  

AbstractThe identification of patient-specific tumor antigens is complicated by the low frequency of T cells specific for each tumor antigen. Here we describe NeoScreen, a method that enables the sensitive identification of rare tumor (neo)antigens and of cognate T cell receptors (TCRs) expressed by tumor-infiltrating lymphocytes. T cells transduced with tumor antigen-specific TCRs identified by NeoScreen mediate regression of established tumors in patient-derived xenograft mice.


Author(s):  
Ting Zhu ◽  
Bo Liu ◽  
Di Wu ◽  
Gang Xu ◽  
Yang Fan

Background: The discovery of ferroptosis is a major breakthrough in the development of cancer treatments. However, the mechanism by which ferroptosis contributes to acute lymphoblastic leukemia (ALL) is to be clarified. Here, we explored erastin-induced ferroptosis in ALL cells and the impact of autophagic activity on this process.Materials and Methods: Cell viability was evaluated in various ALL cell lines following erastin treatment by the MTS assay, while cell death was evaluated via a trypan blue assay. Immunoblotting and quantitative real-time PCR were used to detect protein and mRNA expression, respectively. The UbiBrowser database was used to predict the E3 ligase of VDAC3, which was confirmed by immunoprecipitation. The role of FBXW7 in erastin-induced ferroptosis in vitro was evaluated via lentiviral-mediated silencing and overexpression. ALL xenograft mice were used to observe the impact of autophagy on erastin-induced ferroptosis.Results: Resistance to erastin-induced ferroptosis was higher in Jurkat and CCRF-CEM cells than in Reh cells. The sensitivity could be modified by the autophagy activator rapamycin (Rapa) and the autophagy inhibitor chloroquine (CQ). Rapa sensitized ALL cells to erastin-induced ferroptosis. In ALL xenograft mice, the combination treatment of Rapa and erastin resulted in longer survival time than those observed with erastin or Rapa treatment alone. VDAC3 was regulated by autophagy post-transcriptionally, mainly via the ubiquitin-proteasome system (UPS). FBXW7 was verified as a specific E3 ligase of VDAC3. FBXW7 knockdown attenuated VDAC3 degradation by suppressing its ubiquitination, thereby increasing the sensitivity of ALL cells to erastin.Conclusion: Autophagy regulated erastin-induced ferroptosis via the FBXW7-VDAC3 axis. Rapa sensitized ALL cells to erastin-induced ferroptosis both in vitro and in vivo. Our findings provide potential therapeutic targets for ALL.


2021 ◽  
Author(s):  
Hezhi Wang ◽  
Xiaoxiao Wang ◽  
Xueshuai Ye ◽  
Yi Ju ◽  
Nana Cao ◽  
...  

Abstract Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and the adoptive immunotherapy of which is worth studying. CD133, a kind of cancer stem cell (CSC) antigen, together with glypican-3 (GPC3) have been proved to be highly expressed in HCC cells and both of them are used as targets to generate chimeric antigen receptor (CAR) T cells. But there are limitations like “on-target, off-tumor” toxicity, low transfection efficacy and weak antitumor ability in CAR T cells treatment.Methods: First we fused anti-CD133 and anti-GPC3 single chain Fragment variable (scFv) structures with intracellular domains, respectively. Using non-viral minicircle DNA (mcDNA) vectors to generate co-specific CAR T cells (CoG133-CAR T cells) against CD133 and GPC3 double-positive HCC cells. We exhibited the transduction efficiency of CoG133-CAR T cells and the antigen expression of tumor cell lines. Finally, the antitumor efficacy of CoG133-CAR T cells both in vitro and in vivo was detected. Results: GPC3-CAR and CD133-CAR were successfully prepared using non-viral mcDNA vectors to generate effector cells. For the GPC3 and CD133 double-positive HCC (Huh7) xenograft mice, co-specific CAR T cells possessed stronger tumor growth suppression compared to single-targeted CAR (GPC3-CAR and CD133-CAR) T cells which induced only one antigen-mediated signal pathway. The same results also occurred on the in vitro experiments including cytokine secretion, cytotoxicity and proliferation ability of CAR T cells. Vital organs from CoG133-CAR T cells and normal T cells respectively treated Huh7 xenograft mice were stained by hematoxylin and eosin (H&E), the images showed no difference. Conclusions: The mcDNA vectors loading CAR structures were transfected into T cells by electroporation without genetic mutation or mismatch. Huh7 is an HCC cell line with two antigens of GPC3 and CD133 highly expressed. The antitumor efficacy of co-specific CAR (CoG133-CAR) T cells against Huh7 cells is significantly enhanced. The joint design of two specific targets and non-viral vectors leads much more safety, also.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 733-733
Author(s):  
Anisha M Loeb ◽  
Sommer Castro ◽  
Cynthia Nourigat-Mckay ◽  
LaKeisha Perkins ◽  
Laura Pardo ◽  
...  

Abstract Chimeric antigen receptor (CAR) Ts have been effective in pre-B ALL, but their efficacy in AML has yet to be established. A significant barrier to effective CAR T therapy for AML is the substantial overlap of cell surface antigens expressed on AML and normal hematopoietic cells. To overcome this barrier, we profiled the transcriptome of over 3000 AML cases in children and young adults and contrasted this to normal hematopoietic tissues in search for AML-restricted targets (high expression in AML, silence in normal hematopoiesis). This led to the discovery of over 200 AML-restricted genes. Of these, Preferentially Expressed Antigen in Melanoma (PRAME) is among one of the highest expressing AML-restricted genes (Figure 1A) and, given its previous track record as a target for a variety of cancers, we selected this target for further assessment and therapeutic development in AML. However, PRAME is intracellular and therefore is inaccessible for targeting with conventional CAR T. Recently, a novel approach to target intracellular antigens was developed using TCR mimic (mTCR) antibodies, which recognize peptide/human leukocyte antigen (HLA) complexes on the tumor cell surface in a similar mode of recognition as authentic T Cell Receptors (TCRs). The Pr20 antibody was developed to recognize the PRAME ALY peptide in the context of HLA-A*02. Utilizing this Pr20 antibody, we developed a mTCR CAR T targeting PRAME and evaluated its preclinical efficacy in AML. The VL and VH sequences from Pr20 were used to construct the single-chain fragment variable domain of the 41-BB/CD3ζ CAR vector. We evaluated PRAME mTCR CAR T cells against OCI-AML-2 and THP-1 AML cell lines (PRAME +/HLA-A*02 +), K562 CML cell line (PRAME +/HLA-A*02 -) and HEK293T (293T) (PRAME -/HLA-A*02 +). Using a PE-conjugated Pr20 antibody, we confirmed that OCI-AML2 and THP-1 express PRAME ALY: HLA-A*02 but not K562 and 293T by flow cytometry (Figure 1B). As further confirmation, AML blasts in primary patient samples also stained with the Pr20 antibody (Figure 1C). For in-vivo studies, leukemia-bearing mice were treated with unmodified T or PRAME mTCR CAR T cells at 5x10 6 cells (1:1 CD4:CD8) per mouse 1 week following leukemia injection. Leukemia burden was measured weekly by bioluminescence IVIS imaging. Cells were treated with 10ng/mL of IFN-γ prior to co-incubation with T cells for 16 hours. PRAME mTCR CAR T cells demonstrated potent cytolytic activity against OCI-AML2 and THP1 but not against K562 or 293T cells, following co-incubation with target cells for 24 hours (Figure 1D). Consistent with potent, target-specific reactivity against PRAME ALY: HLA-A*02 positive cells, increased levels of IFN-γ, IL-2 and TNF-α were detected in cocultures of CAR T cells with OCI-AML2 and THP1 but not with K562 and 293T cells (Figure 1D). The cytolytic activity of PRAME mTCR CAR T cells extended to primary AML specimens expressing the PRAME ALY: HLA-A*02 antigen (data not shown). In-vivo efficacy of PRAME mTCR CAR T was demonstrated in OCI-AML2 and THP-1 CDX models (Figure 1E). Treatment with CAR T cells induced leukemia clearance and significantly reduced leukemia burden in OCI-AML2 and THP-1 xenograft mice, respectively, while treatment with unmodified T cells exhibited leukemia progression (Figure 1E). The anti-leukemia activity of CAR T cells resulted in enhanced survival in OCI-AML2 (p=0.0035) and THP-1 (p=0.0047) xenografts (Figure 1F). The in-vivo activity of PRAME mTCR CAR T cells was target specific, as treatment with CAR T cells did not affect leukemia burden and survival in K562 xenograft mice (Figure 1F). Given that IFN-γ promotes PRAME presentation, we investigated whether treatment of IFN-γ would enhance cytolytic activity of PRAME mTCR CAR T cells. OCI-AML2 and THP-1 cells pretreated with IFN-γ were more sensitive to cytolysis compared to untreated controls (Figure 1G). In this study, we demonstrate the therapeutic potential of targeting PRAME with mTCR CAR T cells in AML. We show potent, target-specific reactivity of PRAME mTCR CAR T cells against PRAME ALY: HLA-A*02 positive AML cells, both in-vitro and in-vivo. We further demonstrate that the activity of PRAME mTCR CAR T cells can be enhanced with IFN-γ treatment, providing a useful strategy to increase efficacy. Thus, the results presented provide a novel approach to target PRAME with CAR T cells and compelling data to evaluate PRAME mTCR CAR T cells in AML clinical trials. Figure 1 Figure 1. Disclosures Pardo: Hematologics, Inc.: Current Employment. Hylkema: Quest Diagnostics Inc: Current equity holder in publicly-traded company; Moderna: Current equity holder in publicly-traded company. Scheinberg: Eureka Therapeutics: Current equity holder in publicly-traded company.


2021 ◽  
Vol Volume 16 ◽  
pp. 7685-7695
Author(s):  
Lei Xia ◽  
Li Wen ◽  
Xiangxi Meng ◽  
Nina Zhou ◽  
Xiaoyi Guo ◽  
...  

Author(s):  
Oxana Schmidt ◽  
Nadja Nehls ◽  
Carolin Prexler ◽  
Kristina von Heyking ◽  
Tanja Groll ◽  
...  

Abstract Background Histone acetylation and deacetylation seem processes involved in the pathogenesis of Ewing sarcoma (EwS). Here histone deacetylases (HDAC) class I were investigated. Methods Their role was determined using different inhibitors including TSA, Romidepsin, Entinostat and PCI-34051 as well as CRISPR/Cas9 class I HDAC knockouts and HDAC RNAi. To analyze resulting changes microarray analysis, qRT-PCR, western blotting, Co-IP, proliferation, apoptosis, differentiation, invasion assays and xenograft-mouse models were used. Results Class I HDACs are constitutively expressed in EwS. Patients with high levels of individual class I HDAC expression show decreased overall survival. CRISPR/Cas9 class I HDAC knockout of individual HDACs such as HDAC1 and HDAC2 inhibited invasiveness, and blocked local tumor growth in xenograft mice. Microarray analysis demonstrated that treatment with individual HDAC inhibitors (HDACi) blocked an EWS-FLI1 specific expression profile, while Entinostat in addition suppressed metastasis relevant genes. EwS cells demonstrated increased susceptibility to treatment with chemotherapeutics including Doxorubicin in the presence of HDACi. Furthermore, HDACi treatment mimicked RNAi of EZH2 in EwS. Treated cells showed diminished growth capacity, but an increased endothelial as well as neuronal differentiation ability. HDACi synergizes with EED inhibitor (EEDi) in vitro and together inhibited tumor growth in xenograft mice. Co-IP experiments identified HDAC class I family members as part of a regulatory complex together with PRC2. Conclusions Class I HDAC proteins seem to be important mediators of the pathognomonic EWS-ETS-mediated transcription program in EwS and in combination therapy, co-treatment with HDACi is an interesting new treatment opportunity for this malignant disease.


Sign in / Sign up

Export Citation Format

Share Document