scholarly journals Anti-Tumor Activity vs. Normal Cell Toxicity: Therapeutic Potential of the Bromotyrosines Aerothionin and Homoaerothionin In Vitro

Marine Drugs ◽  
2020 ◽  
Vol 18 (5) ◽  
pp. 236 ◽  
Author(s):  
Antje Drechsel ◽  
Jana Helm ◽  
Hermann Ehrlich ◽  
Snezana Pantovic ◽  
Stefan R. Bornstein ◽  
...  
Keyword(s):  
Normal Tissue ◽  
Therapeutic Potential ◽  
Marine Sponges ◽  
Therapeutic Window ◽  
Proliferating Cells ◽  
Pheochromocytoma Cells ◽  
Hypoxic Conditions ◽  
Pheochromocytoma Cell ◽  
Anti Tumor Activity

Novel strategies to treat cancer effectively without adverse effects on the surrounding normal tissue are urgently needed. Marine sponges provide a natural and renewable source of promising anti-tumor agents. Here, we investigated the anti-tumor activity of Aerothionin and Homoaerothionin, two bromotyrosines isolated from the marine demosponge Aplysina cavernicola, on two mouse pheochromocytoma cells, MPC and MTT. To determine the therapeutic window of these metabolites, we furthermore explored their cytotoxicity on cells of the normal tissue. Both metabolites diminished the viability of the pheochromocytoma cell lines significantly from a concentration of 25 µM under normoxic and hypoxic conditions. Treatment of MPC cells leads moreover to a reduction in the number of proliferating cells. To confirm the anti-tumor activity of these bromotyrosines, 3D-pheochromocytoma cell spheroids were treated with 10 µM of either Aerothionin or Homoaerothionin, resulting in a significant reduction or even complete inhibition of the spheroid growth. Both metabolites reduced viability of normal endothelial cells to a comparable extent at higher micromolar concentration, while the viability of fibroblasts was increased. Our in vitro results show promise for the application of Aerothionin and Homoaerothionin as anti-tumor agents against pheochromocytomas and suggest acceptable toxicity on normal tissue cells.

scholarly journals Long-Term Severe In Vitro Hypoxia Exposure Enhances the Vascularization Potential of Human Adipose Tissue-Derived Stromal Vascular Fraction Cell Engineered Tissues

2021 ◽  
Vol 22 (15) ◽  
pp. 7920
Author(s):  
Myroslava Mytsyk ◽  
Giulia Cerino ◽  
Gregory Reid ◽  
Laia Gili Sole ◽  
Friedrich S. Eckstein ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Therapeutic Potential ◽  
Stromal Vascular Fraction ◽  
Human Adipose Tissue ◽  
Bioreactor Culture ◽  
Proliferating Cells ◽  
Angiogenic Potential ◽  
Engineered Tissues

The therapeutic potential of mesenchymal stromal/stem cells (MSC) for treating cardiac ischemia strongly depends on their paracrine-mediated effects and their engraftment capacity in a hostile environment such as the infarcted myocardium. Adipose tissue-derived stromal vascular fraction (SVF) cells are a mixed population composed mainly of MSC and vascular cells, well known for their high angiogenic potential. A previous study showed that the angiogenic potential of SVF cells was further increased following their in vitro organization in an engineered tissue (patch) after perfusion-based bioreactor culture. This study aimed to investigate the possible changes in the cellular SVF composition, in vivo angiogenic potential, as well as engraftment capability upon in vitro culture in harsh hypoxia conditions. This mimics the possible delayed vascularization of the patch upon implantation in a low perfused myocardium. To this purpose, human SVF cells were seeded on a collagen sponge, cultured for 5 days in a perfusion-based bioreactor under normoxia or hypoxia (21% and <1% of oxygen tension, respectively) and subcutaneously implanted in nude rats for 3 and 28 days. Compared to ambient condition culture, hypoxic tension did not alter the SVF composition in vitro, showing similar numbers of MSC as well as endothelial and mural cells. Nevertheless, in vitro hypoxic culture significantly increased the release of vascular endothelial growth factor (p < 0.001) and the number of proliferating cells (p < 0.00001). Moreover, compared to ambient oxygen culture, exposure to hypoxia significantly enhanced the vessel length density in the engineered tissues following 28 days of implantation. The number of human cells and human proliferating cells in hypoxia-cultured constructs was also significantly increased after 3 and 28 days in vivo, compared to normoxia. These findings show that a possible in vivo delay in oxygen supply might not impair the vascularization potential of SVF- patches, which qualifies them for evaluation in a myocardial ischemia model.

MO1048PHYTOTHERAPY ON RENAL HYPOXIA: THE PREVENTIVE EFFECTS OF HYDROXYTYROSOL - PRELIMINARY IN VITRO RESULTS

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Terézia Kamasová ◽  
Ana Sofia Abreu ◽  
Fátima Paiva-Martins ◽  
Luís Belo ◽  
Alice Santos-Silva ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cell Line ◽  
Therapeutic Potential ◽  
Quantitative Polymerase Chain Reaction ◽  
Oxidative Status ◽  
Hypoxic Conditions ◽  
Thiazolyl Blue Tetrazolium Bromide ◽  
Anti Inflammatory ◽  
Preventive Effects

Abstract Background and Aims Renal hypoxia plays a key role in the pathophysiology of acute kidney injury and in the progression of chronic kidney disease, potentiating other important risk factors for renal disease, such as oxidative stress, renal fibrosis, and inflammation. Hydroxytyrosol (HT) is a phenolic compound extracted from olives and olive-derived products, that has been shown to detain potent in vitro antioxidant and anti-inflammatory activity. The aim of this study was to evaluate the preventive therapeutic potential of HT on a cellular model of renal hypoxia. Method A cell line of normal adult proximal tubular epithelium (HK-2 cell line) was used to determine the effects of the chemical induction of hypoxia with cobalt chloride (CoCl2), as well as the preventive potential of HT on the elicited effects. For this purpose, HK-2 cells were exposed for 24 h to 254 µM CoCl2, to mimic the hypoxic conditions, or pre-incubated for 1 h with 5 µM HT and further exposed to the CoCl2 for 24 h more. Cell viability was assessed by the thiazolyl blue tetrazolium bromide reduction assay. Oxidative status was evaluated by the measurement of reactive oxygen and nitrogen species (ROS and RNS) and reduced glutathione (GSH) levels, by using standardized fluorometric and colorimetric assays. The expression of several genes related to the hypoxic, inflammatory, and fibrotic responses was determined by quantitative polymerase chain reaction (PCR). Results CoCl2-exposed HK-2 cells (hypoxic conditions) showed a significant decrease in cell viability (p &lt; 0.0001 vs. control), and a disruption of the oxidative status, characterized by an increase of ROS and RNS production of about 6-fold over control cells (p &lt; 0.0001) and a decrease in GSH intracellular levels of nearly 50 % (p &lt; 0.05). Although the pre-exposure to HT showed no significant effects on the loss of cell viability elicited by CoCl2, the presence of HT prior to induction of hypoxia reduced the generation of ROS and RNS (p &lt; 0.05 for HT + CoCl2 vs. CoCl2) and prevented the GSH depletion (GSH levels for HT + CoCl2 were similar to those of control) elicited by CoCl2. When compared to control cells, CoCl2-exposed HK-2 cells also showed increased expression of genes related to hypoxia (HIF1A, p &lt; 0.05; GAPDH, p &lt; 0.0001), as well as of modulators of inflammation (IL6, p &lt; 0.0001) and fibrosis (TGFB1, p &lt; 0.05). Importantly, the expression of these genes was partially or even totally suppressed by the pre-exposure of cells to HT (GAPDH, p &lt; 0.01 for HT + CoCl2 vs. CoCl2; expression of HIF1A, IL6 and TGFB1 for HT + CoCl2 was similar to that of control). Conclusion Our data supports the potential for a multiplicity of preventive effects of HT, providing antioxidant, anti-inflammatory and anti-fibrotic defenses to renal cells under hypoxic conditions. Importantly, the development of safe and effective therapeutic approaches based on phytochemicals such as HT, may present substantial advantages for renal patients over synthetic drugs, including fewer side effects, significantly lower price, and ease of administration in the form of dietary supplements. Acknowledgments This work was supported by Applied Molecular Biosciences Unit (UCIBIO), financed by national funds from FCT/MCTES (UIDB/04378/2020), by North Portugal Regional Coordination and Development Commission (CCDR-N)/NORTE2020/Portugal 2020 (Norte-01-0145-FEDER-000024), and co-financed by FCT/MCTES (PTDC/OCE-ETA/32492/2017) and FEDER/COMPETE 2020 (POCI-01-0145-FEDER-032492).

Adrenomedullin: angiogenesis and gene therapy

2005 ◽  
Vol 288 (6) ◽  
pp. R1432-R1437 ◽  
Author(s):  
Noritoshi Nagaya ◽  
Hidezo Mori ◽  
Shinsuke Murakami ◽  
Kenji Kangawa ◽  
Soichiro Kitamura
Keyword(s):  
Gene Transfer ◽  
Cell Biology ◽  
Therapeutic Potential ◽  
Lattice Structure ◽  
Rabbit Model ◽  
Mitogen Activated Protein Kinase ◽  
Tissue Ischemia ◽  
Hypoxic Conditions

Adrenomedullin (AM) is a potent, long-lasting vasodilator peptide that was originally isolated from human pheochromocytoma. AM signaling is of particular significance in endothelial cell biology since the peptide protects cells from apoptosis, promotes angiogenesis, and affects vascular tone and permeability. The angiogenic effect of AM is mediated by activation of Akt, mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2, and focal adhesion kinase in endothelial cells. Both AM and its receptor, calcitonin receptor-like receptor, are upregulated through a hypoxia-inducible factor-1-dependent pathway under hypoxic conditions. Thus AM signaling plays an important role in the regulation of angiogenesis in hypoxic conditions. Recently, we have developed a nonviral vector, gelatin. Positively charged gelatin holds negatively charged plasmid DNA in its lattice structure. DNA-gelatin complexes can delay gene degradation, leading to efficient gene transfer. Administration of AM DNA-gelatin complexes induces potent angiogenic effects in a rabbit model of hindlimb ischemia. Thus gelatin-mediated AM gene transfer may be a new therapeutic strategy for the treatment of tissue ischemia. Endothelial progenitor cells (EPCs) play an important role in endothelial regeneration. Interestingly, EPCs phagocytose ionically linked DNA-gelatin complexes in coculture, which allows nonviral gene transfer into EPCs. AM gene transfer into EPCs inhibits cell apoptosis and induces proliferation and migration, suggesting that AM gene transfer strengthens the therapeutic potential of EPCs. Intravenous administration of AM gene-modified EPCs regenerate pulmonary endothelium, resulting in improvement of pulmonary hypertension. These results suggest that in vivo and in vitro transfer of AM gene using gelatin may be applicable for intractable cardiovascular disease.

In vitro and in vivo activity of ATP-based kinase inhibitors AP23464 and AP23848 against activation-loop mutants of Kit

Blood ◽  
2005 ◽  
Vol 106 (1) ◽  
pp. 227-234 ◽  
Author(s):  
Amie S. Corbin ◽  
Shadmehr Demehri ◽  
Ian J. Griswold ◽  
Yihan Wang ◽  
Chester A. Metcalf ◽  
...  
Keyword(s):  
Cell Lines ◽  
Kinase Inhibitors ◽  
Therapeutic Potential ◽  
Systemic Mastocytosis ◽  
Myelogenous Leukemia ◽  
Therapeutic Window ◽  
Hematopoietic Progenitor Cell ◽  
Activation Loop

Oncogenic mutations of the Kit receptor tyrosine kinase occur in several types of malignancy. Juxtamembrane domain mutations are common in gastrointestinal stromal tumors, whereas mutations in the kinase activation loop, most commonly D816V, are seen in systemic mastocytosis and acute myelogenous leukemia. Kit activation-loop mutants are insensitive to imatinib mesylate and have been largely resistant to targeted inhibition. We determined the sensitivities of both Kit mutant classes to the adenosine triphosphate (ATP)–based inhibitors AP23464 and AP23848. In cell lines expressing activation-loop mutants, low-nM concentrations of AP23464 inhibited phosphorylation of Kit and its downstream targets Akt and signal transducer and activator of transcription 3 (STAT3). This was associated with cell-cycle arrest and apoptosis. Wild-type Kit–and juxtamembrane-mutant–expressing cell lines required considerably higher concentrations for equivalent inhibition, suggesting a therapeutic window in which cells harboring D816V Kit could be eliminated without interfering with normal cellular function. Additionally, AP23464 did not disrupt normal hematopoietic progenitor-cell growth at concentrations that inhibited activation-loop mutants of Kit. In a murine model, AP23848 inhibited activation-loop mutant Kit phosphorylation and tumor growth. Thus, AP23464 and AP23848 potently and selectively target activation-loop mutants of Kit in vitro and in vivo and could have therapeutic potential against D816V-expressing malignancies.

scholarly journals Lithium Improves Survival of PC12 Pheochromocytoma Cells in High-Density Cultures and after Exposure to Toxic Compounds

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Cinzia Fabrizi ◽  
Stefania De Vito ◽  
Francesca Somma ◽  
Elena Pompili ◽  
Angela Catizone ◽  
...  
Keyword(s):  
Cell Death ◽  
Cell Line ◽  
Mammalian Target Of Rapamycin ◽  
Molecular Targets ◽  
High Density ◽  
Therapeutic Window ◽  
Transformed Cells ◽  
Toxic Compounds ◽  
Pheochromocytoma Cells ◽  
Pheochromocytoma Cell

Autophagy is an evolutionary conserved mechanism that allows for the degradation of long-lived proteins and entire organelles which are driven to lysosomes for digestion. Different kinds of stressful conditions such as starvation are able to induce autophagy. Lithium and rapamycin are potent autophagy inducers with different molecular targets. Lithium stimulates autophagy by decreasing the intracellular myo-inositol-1,4,5-triphosphate levels, while rapamycin acts through the inhibition of the mammalian target of rapamycin (mTOR). The correlation between autophagy and cell death is still a matter of debate especially in transformed cells. In fact, the execution of autophagy can protect cells from death by promptly removing damaged organelles such as mitochondria. Nevertheless, an excessive use of the autophagic machinery can drive cells to death via a sort of self-cannibalism. Our data show that lithium (used within its therapeutic window) stimulates the overgrowth of the rat Pheochromocytoma cell line PC12. Besides, lithium and rapamycin protect PC12 cells from toxic compounds such as thapsigargin and trimethyltin. Taken together these data indicate that pharmacological activation of autophagy allows for the survival of Pheochromocytoma cells in stressful conditions such as high-density cultures and exposure to toxins.

scholarly journals It Is Not Just Folklore: The Aqueous Extract of Mung Bean Coat Is Protective against Sepsis

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Shu Zhu ◽  
Wei Li ◽  
Jianhua Li ◽  
Arvin Jundoria ◽  
Andrew E. Sama ◽  
...  
Keyword(s):  
Mung Bean ◽  
Therapeutic Potential ◽  
Survival Rates ◽  
Saline Group ◽  
Therapeutic Window ◽  
Hmgb1 Protein ◽  
Inflammatory Conditions ◽  
Lethal Sepsis

Mung bean (Vigna Radiata) has been traditionally used in China both as nutritional food and herbal medicine against a number of inflammatory conditions since the 1050s. A nucleosomal protein, HMGB1, has recently been established as a late mediator of lethal systemic inflammation with a relatively wider therapeutic window for pharmacological interventions. Here we explored the HMGB1-inhibiting capacity and therapeutic potential of mung bean coat (MBC) extractin vitroandin vivo. We found that MBC extract dose-dependently attenuated LPS-induced release of HMGB1 and several chemokines in macrophage cultures. Oral administration of MBC extract significantly increased animal survival rates from 29.4% (in saline group,N=17mice) to 70% (in experimental MBC extract group,N=17mice,P<0.05).In vitro, MBC extract stimulated HMGB1 protein aggregation and facilitated both the formation of microtubule-associatedprotein-1-light-chain-3-(LC3-)containing cytoplasmic vesicles, and the production of LC3-II in macrophage cultures. Consequently, MBC extract treatment led to reduction of cellular HMGB1 levels in macrophage cultures, which was impaired by coaddition of two autophagy inhibitors (bafilomycin A1 and 3-methyladenine).Conclusion. MBC extract is protective against lethal sepsis possibly by stimulating autophagic HMGB1 degradation.

564 Potency-reduced and extended half-life IL12 heterodimeric Fc-fusions exhibit strong anti-tumor activity with potentially improved therapeutic index compared to native IL12 agents

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A598-A598
Author(s):  
Matthew Bernett ◽  
Rajat Varma ◽  
Ke Liu ◽  
Christine Bonzon ◽  
Rumana Rashid ◽  
...  
Keyword(s):  
Nk Cells ◽  
Half Life ◽  
Single Agent ◽  
Therapeutic Index ◽  
Immune Checkpoints ◽  
Therapeutic Window ◽  
Interleukin 12 ◽  
Severe Toxicity ◽  
Anti Tumor Activity

BackgroundInterleukin-12 (IL12) is a proinflammatory cytokine produced by activated antigen-presenting cells that induces differentiation of Th1 cells and increased proliferation and cytotoxicity of T and NK cells. Stimulation of these cells by IL12 leads to production of high levels of IFNγ. These immune-stimulating aspects of IL12 may help to establish an inflammatory tumor microenvironment critical for anti-tumor responses. Preclinical studies in mice revealed that native IL12 can dramatically shrink syngeneic tumors, however clinical studies in humans resulted in severe toxicity and a small therapeutic window, limiting response rates. Prior work at Xencor demonstrated that reduced-potency IL15/IL15Rα-Fc fusion proteins exhibited superior pharmacokinetics, pharmacodynamics, and safety in non-human primates through reduction of receptor-mediated clearance. Applying similar principles to IL12, we created IL12 heterodimeric Fc-fusions (IL12-Fc) with reduced potency to improve tolerability, slow receptor-mediated clearance, and extend half-life.MethodsIL12 is a heterodimeric protein consisting of two subunits, so we engineered IL12-Fc fusions by fusing the IL12p35 subunit to one side of a heterodimeric (and inactive) Fc domain, and the IL12p40 subunit to the other side. These Fc-fusions were tuned for optimal activity by introducing amino acid substitutions at putative receptor-interface positions and screening for reductions of in vitro potency. In vitro activity was assessed on human PBMCs by measuring signaling in a STAT4 phosphorylation assay and IFNγ production in a mixed-lymphocyte reaction (MLR). In vivo anti-tumor activity was assessed by engrafting MCF-7 cells into PBMC engrafted NSG MHC class I and II double-knockout mice and by measuring tumor volume, lymphocyte activation/proliferation, and IFNγ production over time.ResultsIL12-Fc were produced with good yield and purity. An IL12-Fc potency series was created, and variants had up to a 10,000-fold reduction in STAT4 signaling potency and IFNγ production in an MLR assay compared to native IL12-Fc. Anti-tumor activity in the huPBMC-MCF7 model was achieved with potency-reduced IL12-Fc as a single-agent and in combination with anti-PD1, with weaker variants maintaining anti-tumor activity at higher dose levels. Analysis of peripheral lymphocytes indicated increased numbers of T and NK cells as well as activation of CD8+ T cells, as evidenced by upregulation of CD25. Increased expression of immune checkpoints including PD1 was also observed. Analysis of serum indicated up to 200-fold increases in IFNγ levels.ConclusionsCombined, these data indicate that potency-reduced IL12-Fc retain strong anti-tumor activity, while potentially overcoming safety and tolerability issues related to small therapeutic index associated with recombinant native IL12 or IL12-Fc agents.

Human marrow-derived mesenchymal stromal cells decrease cisplatin renotoxicity in vitro and in vivo and enhance survival of mice post-intraperitoneal injection

2010 ◽  
Vol 299 (6) ◽  
pp. F1288-F1298 ◽  
Author(s):  
Nicoletta Eliopoulos ◽  
Jing Zhao ◽  
Manaf Bouchentouf ◽  
Kathy Forner ◽  
Elena Birman ◽  
...  
Keyword(s):  
Mesenchymal Stromal Cells ◽  
Stromal Cells ◽  
Therapeutic Potential ◽  
Human Kidney ◽  
Chemotherapeutic Agents ◽  
Human Mscs ◽  
Proliferating Cells ◽  
Phosphorylated Akt

Acute kidney injury (AKI) can occur from the toxic side-effects of chemotherapeutic agents such as cisplatin. Bone marrow-derived mesenchymal stromal cells (MSCs) have demonstrated wide therapeutic potential often due to beneficial factors they secrete. The goal of this investigation was to evaluate in vitro the effect of human MSCs (hMSCs) secretome on cisplatin-treated human kidney cells, and in vivo the consequence of hMSCs intraperitoneal (ip) implantation in mice with AKI. Our results revealed that hMSCs-conditioned media improved survival of HK-2 human proximal tubular cells exposed to cisplatin in vitro. This enhanced survival was linked to increased expression of phosphorylated Akt (Ser473) and was reduced by a VEGF-neutralizing antibody. In vivo testing of these hMSCs established that ip administration in NOD-SCID mice decreased cisplatin-induced kidney function impairment, as demonstrated by lower blood urea nitrogen levels and higher survival. In addition, blood phosphorous and amylase levels were also significantly decreased. Moreover, hMSCs reduced the plasma levels of several inflammatory cytokines/chemokines. Immunohistochemical examination of kidneys showed less apoptotic and more proliferating cells. Furthermore, PCR indicated the presence of hMSCs in mouse kidneys, which also showed enhanced expression of phosphorylated Akt. In conclusion, our study reveals that hMSCs can exert prosurvival effects on renal cells in vitro and in vivo, suggests a paracrine contribution for kidney protective abilities of hMSCs delivered ip, and supports their clinical potential in AKI.

scholarly journals 707 IL12 Fc-fusions engineered for reduced potency and extended half-life exhibit strong anti-tumor activity and improved therapeutic index compared to wild-type IL12 agents

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A736-A736
Author(s):  
Matthew Bernett ◽  
Ke Liu ◽  
Christine Bonzon ◽  
Michael Hackett ◽  
Katrina Bykova ◽  
...  
Keyword(s):  
Nk Cells ◽  
Therapeutic Index ◽  
Immune Checkpoints ◽  
Therapeutic Window ◽  
Interleukin 12 ◽  
Severe Toxicity ◽  
Wild Type ◽  
Anti Tumor Activity

BackgroundInterleukin-12 (IL12) is a proinflammatory cytokine that induces differentiation of Th1 cells and increased cytotoxicity of T and NK cells. Stimulation by IL12 leads to production of IFNγ and an inflammatory tumor microenvironment critical for anti-tumor responses. Studies in mice revealed IL12 can dramatically shrink syngeneic tumors, however human clinical studies resulted in severe toxicity and a small therapeutic window, limiting response rates. Prior work at Xencor demonstrated that reduced-potency IL15/IL15Rα-Fc fusion proteins exhibited superior therapeutic index (TI) in non-human primates (NHP) by reducing receptor-mediated clearance. Applying similar principles to IL12, we created IL12 heterodimeric Fc-fusions (IL12-Fc) with reduced potency to improve TI.MethodsIL12 is a heterodimer of two subunits, so we engineered IL12-Fc fusions by fusing the IL12p35 subunit to one side of a heterodimeric (and inactive) Fc domain, and IL12p40 to the other side. These Fc-fusions were tuned for optimal activity by introducing amino acid substitutions at putative receptor-interface positions and screening for reductions of in vitro potency. In vitro activity was assessed on human PBMCs by measuring signaling in a STAT4 phosphorylation assay and IFNγ production in a mixed-lymphocyte reaction (MLR). In vivo anti-tumor activity of human IL12-Fc was assessed in huPBMC-NSG-DKO and huCD34+ MCF7 xenograft models. Surrogate mouse potency-reduced IL12-Fc were evaluated in syngeneic tumor models. Tolerability and pharmacodynamic activity were assessed in NHP.ResultsAn IL12-Fc potency series was created, and variants had up to a 10,000-fold reduction in STAT4 signaling and IFNγ production in an MLR assay compared to wild-type IL12-Fc. Anti-tumor activity was achieved with potency-reduced IL12-Fc as single-agents and in combination with anti-PD1, with weaker variants maintaining anti-tumor activity at higher dose levels. Analysis of peripheral lymphocytes indicated increased numbers of T and NK cells as well as activation of CD8+ T cells. Increased expression of immune checkpoints including PD1 was also observed. Analysis of serum indicated up to 200-fold increases in IFNγ levels. Surrogate potency-reduced IL12-Fc had improved tolerability and greater selectivity of IFNγ production in tumors compared to spleen and less production of IL10 compared to wild-type IL12-Fc. In NHP, potency-reduced IL12-Fc had superior exposure with slower, more sustained accumulation of IFNγ and IP10, and a more gradual dose-dependent peak response, as well as more sustained margination of T and NK cells compared to wild-type IL12-Fc.ConclusionsPotency-reduced IL12-Fc retain strong anti-tumor activity, while potentially overcoming safety and tolerability issues related to narrow TI associated with wild-type IL12 or IL12-Fc agents.

scholarly journals Cabozantinib Is Effective in Melanoma Brain Metastasis Cell Lines and Affects Key Signaling Pathways

2021 ◽  
Vol 22 (22) ◽  
pp. 12296
Author(s):  
Trond Are Mannsåker ◽  
Tuyen Hoang ◽  
Synnøve Nymark Aasen ◽  
Ole Vidhammer Bjørnstad ◽  
Himalaya Parajuli ◽  
...  
Keyword(s):  
Brain Metastasis ◽  
Cell Lines ◽  
Receptor Tyrosine Kinase ◽  
Drug Targets ◽  
Therapeutic Potential ◽  
Melanoma Brain Metastasis ◽  
Monolayer Cultures ◽  
Anti Tumor Activity ◽  
The Brain

Melanomas have a high potential to metastasize to the brain. Recent advances in targeted therapies and immunotherapies have changed the therapeutical landscape of extracranial melanomas. However, few patients with melanoma brain metastasis (MBM) respond effectively to these treatments and new therapeutic strategies are needed. Cabozantinib is a receptor tyrosine kinase (RTK) inhibitor, already approved for the treatment of non-skin-related cancers. The drug targets several of the proteins that are known to be dysregulated in melanomas. The anti-tumor activity of cabozantinib was investigated using three human MBM cell lines. Cabozantinib treatment decreased the viability of all cell lines both when grown in monolayer cultures and as tumor spheroids. The in vitro cell migration was also inhibited and apoptosis was induced by cabozantinib. The phosphorylated RTKs p-PDGF-Rα, p-IGF-1R, p-MERTK and p-DDR1 were found to be downregulated in the p-RTK array of the MBM cells after cabozantinib treatment. Western blot validated these results and showed that cabozantinib treatment inhibited p-Akt and p-MEK 1/2. Further investigations are warranted to elucidate the therapeutic potential of cabozantinib for patients with MBM.

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