scholarly journals A Novel Bispecific Antibody Targeting EGFR and VEGFR2 Is Effective against Triple Negative Breast Cancer via Multiple Mechanisms of Action

Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1027
Author(s):  
Nishant Mohan ◽  
Xiao Luo ◽  
Yi Shen ◽  
Zachary Olson ◽  
Atul Agrawal ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tumor Growth ◽  
Mechanisms Of Action ◽  
Breast Cancers ◽  
Single Chain ◽  
Cancer Cell Growth ◽  
Anti Tumor Activity ◽  
Enhance Tumor Growth

Both EGFR and VEGFR2 frequently overexpress in TNBC and cooperate with each other in autocrine and paracrine manner to enhance tumor growth and angiogenesis. Therapeutic mAbs targeting EGFR (cetuximab) and VEGFR2 (ramucirumab) are approved by FDA for numerous cancer indications, but none of them are approved to treat breast cancers. TNBC cells secrete VEGF-A, which mediates angiogenesis on endothelial cells in a paracrine fashion, as well as promotes cancer cell growth in autocrine manner. To disrupt autocrine/paracrine loop in TNBC models in addition to mediating anti-EGFR tumor growth signaling and anti-VEGFR2 angiogenic pathway, we generated a BsAb co-targeting EGFR and VEGFR2 (designated as anti-EGFR/VEGFR2 BsAb), using publicly available sequences in which cetuximab IgG backbone is connected to the single chain variable fragment (scFv) of ramucirumab via a glycine linker. Physiochemical characterization data shows that anti-EGFR/VEGFR2 BsAb binds to both EGFR and VEGFR2 in a similar binding affinity comparable to parental antibodies. Anti-EGFR/VEGFR2 BsAb demonstrates in vitro and in vivo anti-tumor activity in TNBC models. Mechanistically, anti-EGFR/VEGFR2 BsAb not only directly inhibits both EGFR and VEGFR2 in TNBC cells but also disrupts autocrine mechanism in TNBC xenograft mouse model. Furthermore, anti-EGFR/VEGFR2 BsAb inhibits ligand-induced activation of VEGFR2 and blocks paracrine pathway mediated by VEGF secreted from TNBC cells in endothelial cells. Collectively, our novel findings demonstrate that anti-EGFR/VEGFR2 BsAb inhibits tumor growth via multiple mechanisms of action and warrants further investigation as a targeted antibody therapeutic for the treatment of TNBC.

Abstract 23: Microrna302-367 Sphingosine 1 Phosphate Receptor 1 Pathway Prevents Tumor Growth via Restricting Angiogenesis and Enhancing Vascular Stability

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Jinjiang Pi ◽  
Ting Tao ◽  
Tao Zhuang ◽  
Huimin Sun ◽  
Xiaoli Chen ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tumor Growth ◽  
Ex Vivo ◽  
Downstream Target ◽  
Sprouting Angiogenesis ◽  
Pathological Angiogenesis ◽  
Vascular Stability ◽  
Sphingosine 1 Phosphate

Angiogenic hypersprouting and leaky immature vessels of pathological angiogenesis are essential for tumor growth. MicroRNAs have unique therapeutic advantages by targeting multiple pathways of tumor-associated angiogenesis, but the function of individual miRNAs in angiogenesis and tumors has not yet been fully evaluated. Here, we show that miR302-367 elevation in endothelial cells reduces retina sprouting angiogenesis and promotes vascular stability in vivo, ex vivo and in vitro. Erk1/2 are identified as direct targets of miR302-367, and down-regulation of Erk1/2 upon miR302-367 elevation in endothelial cells increases the expression of Klf2 and in turn S1pr1 and its downstream target VE-cadherin, suppressing angiogenesis and improving vascular stability. Conversely, both pharmacological blockade and genetic deletion of S1pr1 in endothelial cells reverse the anti-angiogenic and vascular stabilizing effect of miR302-367 in mice. Pathological angiogenesis in tumors shares features of developmental angiogenesis, and endothelial specific elevation of miR302-367 reduces tumor growth by restricting sprout angiogenesis and decreasing vascular permeability via the same Erk1/2-Klf2-S1pr1 pathways. In conclusion, miR302-367 regulation of an Erk1/2-Klf2-S1pr1 pathway in the endothelium advances our understanding of angiogenesis, meanwhile also provides opportunities for therapeutic intervention of tumor growth.

Estrogen receptor β represses breast tumor growth and angiogenesis in vivo

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 10101-10101
Author(s):  
J. Hartman ◽  
K. Lindberg ◽  
J. Inzunza ◽  
J. Wan ◽  
A. Ström ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Tumor Growth ◽  
Cancer Cells ◽  
Breast Tumor ◽  
Breast Cancer Cells ◽  
Cancer Cell Growth ◽  
Breast Cancer Cell Growth ◽  
Angiogenic Effect

10101 Background: Estrogens are well known stimulators of breast cancer cell growth in vitro as well as in vivo. Two different estrogen receptors exist, namely estrogen receptor (ER) α and β. ERα mediates the proliferative effect of estrogen in breast cancer cells and we have earlier shown that ERβ inhibits cell-cycle progression in vitro. Estrogens are well known stimulators of in vivo breast cancer cell growth as well as angiogenesis, and the effect is mediated through ERα. The function of ERβ in this context is not well understood. Methods: We have used ERα-positive T47D breast cancer cells stably transfected with a Tet/Off regulated ERβ expression vector system. The ERβ-inducible tumor cells are studied in vitro as well as in vivo. Results: By transplanting ERβ-inducible breast cancer cells into SCID-mice, we show that ERβ inhibits tumor growth and reduces the volume of established tumors. Furthermore, we show by immunohistochemistry, that the number of blood microvessels in the tumor periphery is decreased by ERβ expression, counteracting the well-known pro-angiogenic effect of ERα. By Western blot analysis on tumor extracts, we show that the concentration of the important pro-angiogenic growth factors VEGF and bFGF, normally expressed by breast tumor cells, is decreased in the ERβ-expressing tumors compared to the normal tumors. To exclude that the observed anti-angiogenic effect is just a result of reduced tumor growth, we incubated Tet/Off regulated ERβ expressing cells in vitro, during non-hypoxic conditions. We found that the expression of ERβ leads to decreased expression of VEGF and PDGFβ at the mRNA and protein-levels. In transient transfection assays, we found estrogen-ERα mediated up regulation of VEGF, PDGFβ and bFGF-promoter activities in T47D cells, and these activities were all suppressed following co-transfection with an ERβ-expression vector. Conclusions: We conclude that ERβ inhibits growth factor expression at transcriptional level in breast cancer cells; taken together, our data indicates that ERβ inhibits growth and angiogenesis of tumors formed by T47D breast cancer cells. This makes ERβ an interesting therapeutic target in breast cancer and perhaps treatment with the newly designed ERβ-selective ligands might work as a new anti-proliferative and anti-angiogenic therapy. No significant financial relationships to disclose.

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

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13093-13093 ◽  
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.

Evaluation of the Anti-Tumor Activity of Niclosamide Nanoliposomes Against Colon Carcinoma

2020 ◽  
Vol 13 (3) ◽  
pp. 245-250
Author(s):  
Mahdi Hatamipour ◽  
Mahmoud R. Jaafari ◽  
Amir A. Momtazi-Borojeni ◽  
Mahin Ramezani ◽  
Amirhossein Sahebkar
Keyword(s):  
Tumor Growth ◽  
Experimental Model ◽  
Colon Carcinoma ◽  
Carcinoma Cells ◽  
In Vivo Studies ◽  
Colon Carcinoma Cells ◽  
Ct26 Colon Carcinoma ◽  
Anti Tumor Activity

Background and Aims: Niclosamide is an established anti-helminthic drug, which has recently been shown to inhibit the growth of various cancer cells. To exploit the potential anti-tumor activity of this drug for systemic use, the problem of low aqueous solubility should be addressed. The present study tested the in vivo anti-tumor effects of a recently developed nanoliposomal preparation of niclosamide in an experimental model of colon carcinoma. Methods : The cytotoxicity of nanoliposomal niclosamide on CT26 colon carcinoma cells was evaluated using the MTT test. Inhibition of tumor growth was investigated in BALB/c mice bearing CT26 colon carcinoma cells. The animals were randomly divided into 4 groups including: 1) untreated control, 2) liposomal doxorubicin (15 mg/kg; single intravenous dose), 3) liposomal niclosamide (1 mg/kg/twice a week; intravenously for 4 weeks), and 4) free niclosamide (1 mg/kg/twice a week; intravenously for 4 weeks). To study therapeutic efficacy, tumor size and survival were monitored in 2-day intervals for 40 days. Results: In vitro results indicated that nanoliposomal and free niclosamide could exert cytotoxic effects with IC50 values of 4.5 and 2.5 μM, respectively. According to in vivo studies, nanoliposomal niclosamide showed a higher growth inhibitory activity against CT26 colon carcinoma cells compared with free niclosamide as revealed by delayed tumor growth and prolongation of survival. Conclusion : Nnaoliposomal encapsulation enhanced anti-tumor properties of niclosamide in an experimental model of colon carcinoma.

Methionine gamma-lyase-encapsulated into red blood cells (ERY-MET) antitumor activity in gastric carcinoma.

2017 ◽  
Vol 35 (4_suppl) ◽  
pp. 78-78
Author(s):  
Vanessa Bourgeaux ◽  
Karine Sénéchal ◽  
Karine Aguera ◽  
Fabien Gay ◽  
Françoise Horand
Keyword(s):  
Gastric Carcinoma ◽  
Tumor Growth ◽  
Red Blood Cells ◽  
Cell Lines ◽  
Blood Cells ◽  
Half Life ◽  
Anti Tumor Activity ◽  
Methionine Gamma Lyase

78 Background: Methionine (Met) requirement is a cancer specific–metabolic defect that seems a promising target, especially in gastric cancers. Methionine gamma–lyase (MGL), a pyridoxal–5′–phosphate (PLP)–dependent enzyme, is an emerging approach consisting in tumors Met starvation via systemic Met depletion. ERY-MET is a new therapeutic product overcoming the short in vivo half-life of free MGL by its encapsulation into Red Blood Cells (RBCs). Indeed, ERY-MET works as a bioreactor degrading Met that passively diffuses inside the RBC. In addition, entrapped MGL activity can be controlled by supplying Vitamin B6 (PN), the precursor of MGL’s cofactor (PLP), converted inside RBCs. ERY-MET anti-tumor activity was evaluated in vivo in NMRI nudemice bearing subcutaneous gastric carcinoma. Methods: First, in vitro sensitivity of NCI-N87 and AGS human gastric cell lines to free MGL was assessed by IC50 determination using CCK–8 assay. MGL encapsulated into mouse RBCs by hypotonic dialysis was injected once in CD1 mice to determine PK-PD parameters with or without PN supplementation. The anti-tumor activity of weekly ERY-MET injections (x5) at 116 IU/kg ± 25% was assessed with or without PN supplementation in female NMRI nudemice (n = 10/group) xenografted with NCI-N87 cells. Met depletion was determined 6 days after each cumulative injection while tumor growth was followed twice a week by caliper measurement. Results: In vitro studies showed that NCI-N87 as well as AGS cell lines displayed a sensitivity to free MGL with IC50 of 0.35 ± 0.01 and 0.12 ± 0.02 IU/mL, respectively. ERY-MET with daily PN supplementation significantly increased active MGL half-life in vivo (from < 24h to 8–9 days). ERY-MET induced 80% inhibition of tumor growth at day 45 (p < 0.0001). Response rate obtained was 76% of treated mice (15/20). Besides, PN supplementation induced a slow-down of tumor growth during the supplementation period and improved ERY-MET efficacy. Conclusions: Theses results suggest that ERY-MET can induce tumor growth inhibition in mice bearing human gastric adenocarcinoma and that its effect can be regulated by PN supplementation. As such, ERY-MET seems a promising anti-tumor drug to treat gastric cancers.

Spleen cells of whole body X-irradiated W/Fu rats enhance tumor growth in vivo and non-specific cytotoxicity in vitro

1980 ◽  
Vol 6 (2) ◽  
pp. 183-192 ◽  
Author(s):  
Harold Moroson ◽  
Melvin Schechter ◽  
Thomas Herskovic ◽  
Ilene Kurzman ◽  
Marvin Rotman ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Whole Body ◽  
Spleen Cells ◽  
Specific Cytotoxicity ◽  
Enhance Tumor Growth

Blockade of the CD47/SIRPα Checkpoint Potentiates the Anti-Tumor Efficacy of Tafasitamab

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 11-12
Author(s):  
Doris Mangelberger ◽  
Christian Augsberger ◽  
Karin Landgraf ◽  
Christina Heitmüller ◽  
Stefan Steidl
Keyword(s):  
Monoclonal Antibody ◽  
Tumor Growth ◽  
B Cell ◽  
Tumor Model ◽  
B Cell Lymphoma ◽  
Checkpoint Blockade ◽  
Subcutaneous Tumor ◽  
Anti Tumor Activity

Introduction Tafasitamab (MOR208) is an Fc-enhanced, humanized, monoclonal antibody that targets CD19 and has shown promising clinical activity in patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL). CD19 is homogeneously expressed among different B-cell malignancies, and the binding of tafasitamab to CD19 directly mediates cell death, induces antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis. Aiming to potentiate the tafasitamab-mediated "eat me" signal, we tested a combination with a CD47-directed monoclonal antibody (mAb) to inhibit the CD47/SIRPα "don't eat me" signal and further enhance macrophage-mediated phagocytosis. Preclinical studies demonstrated that blocking the CD47/SIRPα checkpoint in combination with antibodies, such as rituximab, increased phagocytosis by macrophages, resulting in effective anti-tumor effects in non-Hodgkin lymphoma (NHL) (Chao, et al. 2010). Additionally, the combination of the anti-CD47, magrolimab, and the anti-CD20, rituximab, demonstrated beneficial outcomes for patients with refractory NHL (Advani, et al. 2019). Here, we present in vitro and in vivo data on the combinatory effect of tafasitamab and an anti-CD47 mAb in preclinical models of Burkitt's lymphoma (BL). Methods During in vitro studies, CD14+ monocytes were isolated from the whole blood of healthy volunteers and differentiated with 50 ng/mL M-CSF for 6 days. ADCP was analyzed by flow cytometry in co-culture experiments with Ramos cells (BL) after 3 hours of treatment with tafasitamab and anti-CD47 mAb (clone B6H12). In vivo, the combination of tafasitamab with an anti-CD47 mAb was tested in a Ramos disseminated survival and subcutaneous tumor model in SCID and NOD-SCID mice, respectively. In both models, tafasitamab was administered therapeutically twice a week either at 3 mg/kg (disseminated) or 10 mg/kg (subcutaneous) for max. 4 weeks. The anti-CD47 mAb was administered at 4 mg/kg three times per week. Main study readouts were to assess animal survival and any delays in tumor growth. Results The combination of tafasitamab + CD47/SIRPα checkpoint blockade enhanced ADCP activity of primary M2 macrophages on BL-derived Ramos cells, in comparison with the anti-CD47 mAb or tafasitamab monotherapies (Figure 1A). In vivo, a significant increase in anti-tumor activity was observed with the combination of tafasitamab + anti-CD47 mAb. In the Ramos disseminated survival model, the combination showed an increased life span (ILS) of &gt;182% compared with tafasitamab monotherapy control, with an overall survival of all animals treated with the combination (15/15) until the end of the study (Day 99 post-cell injection). Additionally, pronounced anti-tumor efficacies were detected in the Ramos subcutaneous tumor model. Here, the combination resulted in a significant delay in tumor growth compared with the tafasitamab or anti-CD47 mAb monotherapies (ILS &gt;175% tafasitamab and ILS &gt;72% anti-CD47 mAb vs tafasitamab + B6H12) (Figure 1B). Conclusions The ADCP activity of primary macrophages was increased by combining tafasitamab with an anti-CD47 mAb in vitro, resulting in enhanced anti-tumor activity compared with tafasitamab or anti-CD47 mAb monotherapies in vivo. Overall, results indicate the combination of tafasitamab with a CD47/SIRPα checkpoint blockade may be a promising novel combination approach for lymphoma therapy. Disclosures Mangelberger: MorphoSys AG: Current Employment. Augsberger:MorphoSys AG: Current Employment. Landgraf:MorphoSys AG: Current Employment. Heitmüller:MorphoSys AG: Current Employment. Steidl:MorphoSys AG: Current Employment.

Dual effects for lovastatin in anaplastic thyroid cancer: the pivotal effect of transketolase (TKT) on lovastatin and tumor proliferation

2018 ◽  
Vol 66 (5) ◽  
pp. 1.4-9 ◽  
Author(s):  
Chih-Yuan Wang ◽  
Hao-Ai Shui ◽  
Tien-Chun Chang
Keyword(s):  
Thyroid Cancer ◽  
Cell Growth ◽  
Protein Expression ◽  
Tumor Growth ◽  
Anaplastic Thyroid Cancer ◽  
Control Group ◽  
Cancer Cell Growth ◽  
Protein Levels

This study tested the hypothesis that the effects of lovastatin on anaplastic thyroid cancer cell growth are mediated by upregulation of transketolase (TKT) expression. The effects of lovastatin on TKT protein levels in ARO cells were determined using western blot and proteomic analyses. After treatment with lovastatin and oxythiamine, the in vitro and in vivo growth of ARO cells was determined using 3-(4,5-Dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assays and tumor xenografts in nude mice. TKT protein expression in the ARO tumors was assessed using immunohistochemistry analysis. Proteomic analysis revealed that 25 µM lovastatin upregulated TKT expression. Co-treatment of ARO cells with 1 µM lovastatin + 1 µM oxythiamine increased TKT protein expression compared with control levels; however, no differences were observed with 10 µM lovastatin + 1 µM oxythiamine. Furthermore, treatment with either oxythiamine or lovastatin alone reduced ARO tumor expression of TKT, as well as decreased ARO cell proliferation in vitro and tumor growth in vivo. However, mice treated with both lovastatin and oxythiamine at the same time had tumor volumes similar to that of the untreated control group. We conclude that either lovastatin or oxythiamine reduced ARO cell growth; however, the combination of these drugs resulted in antagonism of ARO tumor growth.

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