Inhibition of nicotinamide phosphoribosyltransferase (NAMPT) with OT-82 induces DNA damage, cell death, and suppression of tumor growth in preclinical models of Ewing sarcoma

Abstract NAMPT mediates the rate-limiting step of the NAD salvage pathway, which maintains cellular bioenergetics and provides a necessary substrate for functions essential to rapidly proliferating cancer cells. In this study, we evaluated the efficacy and mechanisms of action of OT-82, a novel, high-potency NAMPT inhibitor with a favorable toxicity profile, in preclinical models of Ewing sarcoma (EWS), an aggressive pediatric malignancy with previously reported selective sensitivity to NAMPT inhibition. We show that OT-82 decreased NAD concentration and impaired proliferation of EWS cells in a dose-dependent manner, with IC50 values in the single-digit nanomolar range. Notably, genetic depletion of NAMPT phenocopied pharmacological inhibition. On-target activity of OT-82 was confirmed with the addition of NMN, the product of NAMPT, which rescued NAD concentration and EWS cellular viability. Mechanistically, OT-82 treatment resulted in impaired DNA damage repair through loss of PARP activity, G2 cell-cycle arrest, and apoptosis in EWS cells. Additional consequences of OT-82 treatment included reduction of glycolytic and mitochondrial activity. In vivo, OT-82 impaired tumor growth and prolonged survival in mice bearing EWS xenografts. Importantly, antitumor effect correlated with pharmacodynamic markers of target engagement. Furthermore, combining low-dose OT-82 with low doses of agents augmenting DNA damage demonstrated enhanced antitumor activity in vitro and in vivo. Thus, OT-82 treatment represents a potential novel targeted approach for the clinical treatment of EWS.

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The mechanism of low molecular weight heparin (LMWH) inhibition of tumor growth

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.13093 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 13093-13093 ◽

Cited By ~ 4

Author(s):

S. L. Smiley ◽

D. O. Henry ◽

M. K. Wong

Keyword(s):

Endothelial Cells ◽

Tumor Growth ◽

Dependent Manner ◽

Concentration Dependent Manner ◽

Receptor System ◽

Fgf Receptor ◽

Tumor Inhibition ◽

Inhibition Of Tumor Growth

13093 Background: Clinical studies show that LMWHs improve survival in cancer patients. There is compelling and mounting evidence that non-anticoagulation factors are at play, and that these may be contributing in a major way to improved patient outcome. Methods and Results: Dalteparin, enoxaparin, and tinzaparin were tested for their in vivo ability to inhibit tumor lines engineered for aggressive angiogenesis-driven growth. Therapeutic daily doses of drug administered the day following tumor inoculation resulted in significant angiogenesis and tumor inhibition. We previously showed that LMWHs inhibit fibroblast growth factor (FGF) -induced mitogenesis of Tumor Derived Endothelial Cells (TDECs) in a time and concentration dependent manner in vitro. We now show that this endothelial inhibition occurs through LMWHs-mediated reduction of phosphorylation and down stream signaling through ERK. The potency of LMWH was significantly reduced when TDECs were pretreated with heparinase- suggesting that the molecular target for LMWH may be the cell surface, low affinity FGF receptor system. Both our in vivo and in vitro studies demonstrate that angiogenesis and tumor inhibition are greatest for dalteparin > tinzaparin > enoxaparin. Clues to the heparin-TDECs interaction comes from tracking the real-time movement of FGF using a highly fluorescent nanocrystal bead decorated on its surface with FGF. High resolution video-microscopy shows FGF binding onto TDEC surfaces, but once heparin enters the environment, FGF detaches from the TDECs and migrates to the heparin. This ultimately results in significant TDEC growth inhibition as compared to controls. Conclusion: LMWH treatment at pharmacologic doses significantly blunts tumor growth and angiogenesis. This inhibition resides in part via heparin’s ability to sequester FGF from the low affinity receptor system on tumor endothelial cells. No significant financial relationships to disclose.

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Cytotoxic effect of Montivipera bornmuelleri’s venom on cancer cell lines: in vitro and in vivo studies

PeerJ ◽

10.7717/peerj.9909 ◽

2020 ◽

Vol 8 ◽

pp. e9909

Author(s):

Carol Haddoub ◽

Mohamad Rima ◽

Sandrine Heurtebise ◽

Myriam Lawand ◽

Dania Jundi ◽

...

Keyword(s):

Tumor Growth ◽

Cell Lines ◽

Cytotoxic Effect ◽

In Vivo Studies ◽

Dependent Manner ◽

In Vivo Testing ◽

Murine Fibrosarcoma ◽

Dose Dependent

Background Montivipera bornmuelleri’s venom has shown immunomodulation of cytokines release in mice and selective cytotoxicity on cancer cells in a dose-dependent manner, highlighting an anticancer potential. Here, we extend these findings by elucidating the sensitivity of murine B16 skin melanoma and 3-MCA-induced murine fibrosarcoma cell lines to M. bornmuelleri’s venom and its effect on tumor growth in vivo. Methods The toxicity of the venom on B16 and MCA cells was assessed using flow cytometry and xCELLigence assays. For in vivo testing, tumor growth was followed in mice after intratumoral venom injection. Results The venom toxicity showed a dose-dependent cell death on both B16 and MCA cells. Interestingly, overexpression of ovalbumin increased the sensitivity of the cells to the venom. However, the venom was not able to eradicate induced-tumor growth when injected at 100 µg/kg. Our study demonstrates a cytotoxic effect of M. bornmuelleri’s venom in vitro which, however, does not translate to an anticancer action in vivo.

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4SC-202 Exerts An Anti-tumor Effect in Cervical Cancer By Targeting PRLR Signaling Pathway

10.21203/rs.3.rs-1072706/v1 ◽

2021 ◽

Author(s):

Huijuan Zhang ◽

Mingxia Li ◽

Wen Yang ◽

Mingxia Ye ◽

Hua Li ◽

...

Keyword(s):

Cervical Cancer ◽

Tumor Growth ◽

Western Blotting ◽

Prolactin Receptor ◽

Cell Cycle Distribution ◽

Dependent Manner ◽

Siha Cells ◽

Serum Biochemical

Abstract The aim of the present study is to investigate whether 4SC-202, a selective class I histone deacetylase inhibitor (HDACi), plays an anti-tumor role in cervical cancer (CC) by targeting prolactin receptor (PRLR). CCK-8 and colony formation assays were used to evaluate the effects of 4SC-202 on the proliferation of CC cells in vitro. Effects of 4SC-202 on the cell cycle distribution and apoptosis in SiHa cells were determined by flow cytometry and western blotting, respectively. Immunofluorescence and western blotting were performed to detect the activities of PRLR-related pathways and PRLR expression in CC cells. A xenograft tumor model in nude mice was established to examine effects of 4SC-202 on the tumor growth, apoptosis and PRLR-related pathways in vivo. The biochemical analyzer and H&E staining were used to detect the serum biochemical indexes and organ toxicity. 4SC-202 inhibited the proliferation of CC cells (SiHa, HeLa, and CaSki) in vitro in a time- and dose-dependent manner. SiHa cells were treated with 1 or 5 μM 4SC-202 for 72 h and then subjected to various functional assays. The assays showed that 4SC-202 significantly induced G2/M phase arrest and apoptosis, while inhibiting the activities of PRLR-related pathways and PRLR expression. In addition, 4SC-202 reduced tumor growth and induced apoptosis in vivo. 4SC-202 down-regulated the expression of PRLR and activities of PRLR-related pathways in the mouse model, displayed no effects on serum biochemical indicators and caused no toxicity to mouse organs. This finding suggests that 4SC-202 may serve as a novel therapeutic agent for CC.

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Neuronal Repressor REST Controls Ewing Sarcoma Growth and Metastasis by Affecting Vascular Pericyte Coverage and Vessel Perfusion

Cancers ◽

10.3390/cancers12061405 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1405

Author(s):

Zhichao Zhou ◽

Yuanzheng Yang ◽

Fei Wang ◽

Eugenie S. Kleinerman

Keyword(s):

Tumor Growth ◽

Ewing Sarcoma ◽

Vascular Function ◽

Fusion Gene ◽

Critical Role ◽

Survival Rates ◽

Tumor Vasculature ◽

Tumor Growth And Metastasis

Survival rates for Ewing sarcoma (ES) patients with metastatic disease have not improved in over 20 years. Tumor growth and metastasis are dependent on tumor vasculature expansion; therefore, identifying the regulators that control this process in ES may provide new therapeutic opportunities. ES expresses high levels of repressor element 1 silencing transcription factor (REST), which is regulated by the EWS-FLI-1 fusion gene. However, the role of REST in ES growth and the regulation of the tumor vasculature have not been elucidated. To study this role, we established REST-knockout human TC71 ES cell lines through CRISPR/Cas9 recombination. While knockout of REST did not alter tumor cell proliferation in vitro, REST knockout reduced tumor growth and metastasis to the lung in vivo and altered tumor vascular morphology and function. Tumor vessels in the REST-knockout tumors had a punctate appearance with significantly decreased tumor vascular pericytes, decreased perfusion, and increased permeability. REST-knockout tumors also showed increased apoptosis and hypoxia. These results indicate that REST plays a critical role in ES vascular function, which in turn impacts the ability of ES tumors to grow and metastasize. These findings therefore provide a basis for the targeting of REST as a novel therapeutic approach in ES.

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Studies of pemetrexed and gemcitabine, alone and in combinations, in human lung cancer models

Journal of Clinical Oncology ◽

10.1200/jco.2006.24.18_suppl.17114 ◽

2006 ◽

Vol 24 (18_suppl) ◽

pp. 17114-17114 ◽

Cited By ~ 2

Author(s):

D. C. Chan ◽

V. J. Chen ◽

Z. Zhang ◽

B. Helfrich ◽

F. R. Hirsch ◽

...

Keyword(s):

Tumor Growth ◽

Cell Lines ◽

In Vivo Studies ◽

Human Lung Cancer ◽

Dependent Manner ◽

Antitumor Effects ◽

Nude Rats ◽

Combination Regimens

17114 Background: Gemcitabine (GEM) is a deoxycytidine analog that inhibits DNA synthesis. Pemetrexed (ALIMTA, PEM) is a novel antifolate inhibiting multiple enzymes targets, including thymidylate synthase (TS). This study aimed at evaluating the antitumor effects of these antimetabolites against NSCLC and SCLC tumor models. Methods: In vitro growth inhibition (IC50) studies were done by 6-days MTT assays against a panel of 20 NSCLC and 17 SCLC cell lines. In vivo studies used only NSCLC H2122 tumor line, implanted either subcutaneously in athymic nude mice or orthotopically in athymic nude rats. Drugs were given via the ip route at the designated schedules. Results: Against NSCLC and SCLC cell lines, the averaged IC50s of GEM were 0.015 ± 0.008 μM and 0.055 ± 0.04 μM respectively. The corresponding averaged IC50s for PEM were 0.65 ± 0.2 μM and 0.091±0.018 μM respectively. When H2122 tumors reached 50–100mg, mice were treated with 10 daily doses of PEM at 100, 200 and 300 mg/kg, or three doses of GEM every 4 days at 30, 60 and 120 mg/kg. PEM delayed tumor growth by 12 to 18 days, and GEM delayed by 10 to 14 days, relative to vehicle control. Results of three combination regimens with GEM (30 mg/kg) and PEM (100 mg/kg) were: (1) GEM → PEM gave intermediate activities between the two single agents, but was toxic to animals; (2) PEM and GEM given concurrently were more active than single agents alone and delayed tumor growth by 12 days with some toxic side effects; (3) PEM → GEM was better than the single agents alone, and delayed tumor growth by ∼14 days without toxicity. Athymic nude rats bearing orthotopic H2122 tumors given PEM daily at 50, 100 and 200 mg/kg for 21 days had significantly prolonged survival, but not in a dose-dependent manner. PEM at 50 mg/kg was more effective than doses at 100 or 200 mg/kg. GEM was toxic to nude rats due to poor plasma deamination of GEM. Conclusions: In vitro, PEM was more potent against SCLC than NSCLC cell lines, but GEM had similar activities against all lung lines tested. Studies of H2122 xenografts in rodent supported PEM → GEM as the preferred sequence for the combined administration of these two drugs. [Table: see text]

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Efficacy of adavosertib therapy against anaplastic thyroid cancer

Endocrine Related Cancer ◽

10.1530/erc-21-0001 ◽

2021 ◽

Author(s):

Yu-Ling Lu ◽

Yu-Tung Huang ◽

Ming-Hsien Wu ◽

Ting-Chao Chou ◽

Richard J Wong ◽

...

Keyword(s):

Thyroid Cancer ◽

Tumor Growth ◽

Single Agent ◽

Xenograft Model ◽

Anaplastic Thyroid Cancer ◽

Therapeutic Effects ◽

Dependent Manner ◽

Cancer Tumor

Wee1 is a kinase that regulates the G2/M progression by inhibition of CDK1, which is critical for ensuring DNA damage repair before initiation of mitotic entry. Targeting Wee1 may be a potential strategy in the treatment of anaplastic thyroid cancer, a rare but lethal disease. The therapeutic effects of adavosertib, a Wee1 inhibitor for anaplastic thyroid cancer was evaluated in this study. Adavosertib inhibited cell growth in three anaplastic thyroid cancer cell lines in a dose-dependent manner. Cell cycle analysis revealed cells were accumulated in the G2/M phase. Adavosertib induced caspase-3 activity and led to apoptosis. Adavosertib monotherapy showed significant retardation of the growth of two anaplastic thyroid cancer tumor models. The combination of adavosertib with dabrafenib and trametinib revealed strong synergism in vitro and demonstrated robust suppression of tumor growth in vivo in anaplastic thyroid cancer xenograft models with BRAFV600E mutation. The combination of adavosertib with either sorafenib or lenvatinib also demonstrated synergism in vitro and had strong inhibition of tumor growth in vivo in an anaplastic thyroid cancer xenograft model. No appreciable toxicity appeared in mice treated with either single agent or combination treatment. Our findings suggest adavosertib holds the promise for the treatment of patients with anaplastic thyroid cancer.

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Synergic Effects of Proteasome Inhibitor PS-341 and Tyrosine Kinase Inhibitor STI571 on Chronic Myeloid Leukemia Cells and BCR-ABL Oncoprotein In Vitro and In Vivo.

Blood ◽

10.1182/blood.v108.11.4771.4771 ◽

2006 ◽

Vol 108 (11) ◽

pp. 4771-4771

Author(s):

Guangbiao Zhou ◽

Zheng Hu ◽

Dapeng Liu ◽

Fuqun Wu ◽

Jiang Zhu ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Tumor Growth ◽

Proteasome Inhibitor ◽

Myeloid Leukemia ◽

K562 Cells ◽

Leukemic Cells ◽

Great Promise ◽

Dependent Manner

Abstract STI571/Gleevec/imatinib, a rationally-designed agent that occupies the ATP-binding site of BCR-ABL and stabilizes the protein in its closed, inactive conformation, has been a remarkable success for the treatment of chronic myeloid leukemia (CML). However, a significant proportion of patients chronically treated with STI571 develop resistance because of the acquisition of mutations in the kinase domain of BCR-ABL. Furthermore, the effects of STI571 on CML patients in accelerated phase or blastic crisis are unsatisfactory since many patients relapse after transient remission. Hence, additional drugs or STI571-based combination regimens are desired to circumvent resistance and to improve response rates. Here we reported that PS-341, a proteasome inhibitor which offers great promise to patients with multiple myeloma (MM), significantly enhanced the antileukemia activity of STI571 in vitro and in vivo. We found a synergy exists between low concentrations of PS-341 (5–10 nM) and STI571 (0.1–0.2 μM) in inhibition of cell growth and induction of apoptosis in K562 cell line and CD34+ leukemic cells isolated from CML patients. In K562 cells, combined use of PS-341 and STI571 accelerated activation of caspase-3, 9, and facilitated cleavage of poly-(ADP-ribose) polymerase (PARP) as compared to those in cells treated with PS-341 or STI571 alone. Moreover, PS-341/STI571 combination resulted in potentiated degradation of BCR-ABL and downregulation of phosphorylated BCR-ABL as compared to those in mono treatment. In nude mice inoculated subcutaneously with K562 cells, treatment with PS-341 (injected intraperitoneally, ip) alone (at doses of 0.05, 0.5, 1 mg/kg/d, twice a week for 4 weeks, respectively) decreased tumor growth in a dose-dependent manner. STI571 (ip) at 10 mg/kg/d also inhibited tumor growth. Intriguingly, combinatory administration of low dose PS-341 (0.05 mg/kg/d, twice a week for 4 weeks) and STI571 (10 mg/kg/d) yielded a much more profound inhibition of tumor growth and even clearance of leukemic cells in mice compared to either monotherapy. Taken together, these results demonstrate synergic effects of PS-341 and STI571, and provide the rationale to evaluate PS-341/STI571 combination in treating CML aiming to further improve clinical outcome of patients.

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Dysregulated heparan sulfate proteoglycan metabolism promotes Ewing sarcoma tumor growth

10.1101/2021.05.25.445683 ◽

2021 ◽

Author(s):

Elena Vasileva ◽

Mikako Warren ◽

Timothy J Triche ◽

James F Amatruda

Keyword(s):

Extracellular Matrix ◽

Tumor Growth ◽

Heparan Sulfate ◽

Ewing Sarcoma ◽

Target Genes ◽

Genetic Model ◽

Rapid Onset ◽

Relapsed Disease

The Ewing sarcoma family of tumors is a group of malignant small round blue cell tumors (SRBCTs) that affects children, adolescents and young adults. The tumors are characterized by reciprocal chromosomal translocations that generate chimeric fusion oncogenes, the most common of which is EWSR1-FLI1. Survival is extremely poor for patients with metastatic or relapsed disease, and no molecularly-targeted therapy for this disease currently exists. The absence of a reliable genetic animal model of Ewing sarcoma has impaired investigation of tumor cell/microenvironmental interactions in vivo. We have developed a new genetic model of Ewing sarcoma based on Cre-inducible expression of human EWSR1-FLI1 in wild type zebrafish, which causes rapid onset of SRBCTs at high penetrance. The tumors express canonical EWSR1-FLI1 target genes and stain for known Ewing sarcoma markers including CD99. Growth of tumors is associated with activation of the MAPK/ERK pathway, which we link to dysregulated extracellular matrix metabolism in general and heparan sulfate catabolism in particular. Targeting heparan sulfate proteoglycans with the specific heparan sulfate antagonist Surfen reduces ERK1/2 signaling and decreases tumorigenicity of Ewing sarcoma cells in vitro and in vivo. These results highlight the important role of the extracellular matrix in Ewing sarcoma tumor growth and the potential of agents targeting proteoglycan metabolism as novel therapies for this disease.

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O-Acetyl-GD2 as a Therapeutic Target for Breast Cancer Stem Cells

Frontiers in Immunology ◽

10.3389/fimmu.2021.791551 ◽

2022 ◽

Vol 12 ◽

Author(s):

Jing-Yan Cheng ◽

Jung-Tung Hung ◽

Juway Lin ◽

Fei-Yun Lo ◽

Jing-Rong Huang ◽

...

Keyword(s):

Breast Cancer ◽

Stem Cells ◽

Cancer Stem Cells ◽

Tumor Growth ◽

Dependent Manner ◽

Breast Cancer Stem Cells ◽

Lipid Molecule ◽

Mammosphere Formation

SynopsisA sugar-lipid molecule called OAcGD2 is a novel marker for breast cancer stem cells. Treatment with anti-OAcGD2 mAb8B6 may have superior anticancer efficacy by targeting cancer stem cells, thereby reducing metastasis and recurrence of cancer.BackgroundCancer stem cells (CSCs) that drive tumor progression and disease recurrence are rare subsets of tumor cells. CSCs are relatively resistant to conventional chemotherapy and radiotherapy. Eradication of CSCs is thus essential to achieve durable responses. GD2 was reported to be a CSC marker in human triple-negative breast cancer, and anti-GD2 immunotherapy showed reduced tumor growth in cell lines. Using a specific anti-OAcGD2 antibody, mAb8D6, we set out to determine whether OAcGD2+ cells exhibit stem cell properties and mAb8D6 can inhibit tumor growth by targeting OAcGD2+CSCs.MethodOAcGD2 expression in patient-derived xenografts (PDXs) of breast cancer was determined by flow cytometric analyses using mAb8D6. The stemness of OAcGD2+ cells isolated by sorting and the effects of mAb8B6 were assessed by CSC growth and mammosphere formation in vitro and tumor growth in vivo using PDX models.ResultWe found that the OAcGD2 expression levels in six PDXs of various molecular subtypes of breast cancer highly correlated with their previously defined CSC markers in these PDXs. The sorted OAcGD2+ cells displayed a greater capacity for mammosphere formation in vitro and tumor initiation in vivo than OAcGD2− cells. In addition, the majority of OAcGD2+ cells were aldehyde dehydrogenase (ALDH+) or CD44hiCD24lo, the known CSC markers in breast cancer. Treatment of PDXs-bearing mice with mAb8B6, but not doxorubicin, suppressed the tumor growth, along with reduced CSCs as assessed by CSC markers and in vivo tumorigenicity. In vitro, mAb8B6 suppressed proliferation and mammosphere formation and induced apoptosis of OAcGD2+ breast cancer cells harvested from PDXs, in a dose-dependent manner. Finally, administration of mAb8B6 in vivo dramatically suppressed tumor growth of OAcGD2+ breast CSCs (BCSCs) with complete tumor abrogation in 3/6 mice.ConclusionOAcGD2 is a novel marker for CSC in various subtypes of breast cancer. Anti-OAcGD2 mAb8B6 directly eradicated OAcGD2+ cells and reduced tumor growth in PDX model. Our data demonstrate the potential of mAb8B6 as a promising immunotherapeutic agent to target BCSCs.

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POGZ modulates the DNA damage response in a HP1-dependent manner

10.1101/2021.06.28.447216 ◽

2021 ◽

Author(s):

John Heath ◽

Estelle Simo Cheyou ◽

Steven Findlay ◽

Vincent Luo ◽

Edgar Pinedo Carpio ◽

...

Keyword(s):

Dna Damage ◽

Dna Repair ◽

Dna Damage Response ◽

Genome Stability ◽

Dependent Manner ◽

Dna Double Strand Breaks ◽

Humoral Immune ◽

Damage Response

The heterochromatin protein HP1 plays a central role in the maintenance of genome stability, in particular by promoting homologous recombination (HR)-mediated DNA repair. However, little is still known about how HP1 is controlled during this process. Here, we describe a novel function of the POGO transposable element derived with ZNF domain protein (POGZ) in the regulation of HP1 during the DNA damage response in vitro. POGZ depletion delays the resolution of DNA double-strand breaks (DSBs) and correlates with an increased sensitivity to different DNA damaging agents, including the clinically-relevant Cisplatin and Talazoparib. Mechanistically, POGZ promotes homology-directed DNA repair pathways by retaining the BRCA1/BARD1 complex at DSBs, in a HP1-dependent manner. In vivo CRISPR inactivation of Pogz is embryonic lethal and Pogz haplo-insufficiency (Pogz+/Δ) results in a developmental delay, a deficit in intellectual abilities, a hyperactive behaviour as well as a compromised humoral immune response in mice, recapitulating the main clinical features of the White Sutton syndrome (WHSUS). Importantly, Pogz+/Δ mice are radiosensitive and accumulate DSBs in diverse tissues, including the spleen and the brain. Altogether, our findings identify POGZ as an important player in homology-directed DNA repair both in vitro and in vivo, with clinical implications for the WHSUS.

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