Influence of liposomal irinotecan (nal-IRI) and non-liposomal irinotecan, alone and in combination, on tumor growth and angiogenesis in colorectal cancer (CRC) models.

2018 ◽  
Vol 36 (4_suppl) ◽  
pp. 711-711 ◽  
Author(s):  
Annette K Larsen ◽  
Cristiano Trindade ◽  
Anaïs Bouygues ◽  
Lila K Louadj ◽  
Sandrine K Thouroude ◽  
...  

711 Background: The long circulating liposomal irinotecan nal-IRI (MM-398/PEP02, Onivyde) is approved for treatment of metastatic pancreatic cancer after disease progression with gemcitabine-based therapy. Besides their direct cytotoxic activity, camptothecins are thought to inhibit tumor angiogenesis via downregulating hypoxia-inducible factor 1 leading to attenuation of VEGF expression. Due to different deposition kinetics, irinotecan HCl and nal-IRI are likely to show different activities in vivo suggesting that a combination of the two agents may optimize intratumoral exposure and improve treatment efficacy. Methods: The activities of nal-IRI, irinotecan and their combination were compared in three human CRC xenograft models with different sensitivity to SN-38, the active metabolite of irinotecan, in vitro. Nal-IRI was dosed at 5 mg/kg q7d, while irinotecan HCl was dosed at 25 mg/kg at days 1 and 2 q7d. The activity of different regimens on tumor cell viability, hypoxia markers and the microvascular density was determined by quantitative biomarker analysis. Results: The relative antitumor activity of nal-IRI was most pronounced in tumor models with natural or acquired irinotecan resistance. Combinations of nal-IRI with irinotecan HCl was significantly better than irinotecan HCl alone in all tumor models although nal-IRI only provided 10% additional irinotecan. The antitumor activity of nal-IRI and Irintecan HCl in combination was accompanied by up to two times more tumor cell death and a marked 3-7 fold reduction of the microvessel density. Despite the strong antiangiogenic effect resulting in tumor hypoxia, the increase in HIF1α and, to lesser degree, HIF2α, was relatively modest and VEGF signal intensity remained at 85-115% of control values. Conclusions: Our results suggest that both irinotecan HCl and nal-IRI can counteract the hypoxia-mediated increase of HIF1α in vivo as previously reported in vitro. Furthermore, the combination of the two formulations demonstrated significant efficacy benefits. A combination of irinotecan HCl and nal-IRI merits further clinical investigation.

1982 ◽  
Vol 68 (5) ◽  
pp. 365-371 ◽  
Author(s):  
Ornella Marelli ◽  
Alberto Mantovani ◽  
Paola Franco ◽  
Angelo Nicotin

Murine leukemic cells, after in vivo treatment with antineoplastic drugs, have been shown to express new antigenic specificities that were not detectable on parental cells and that were heritable after the withdrawal of drug treatment. A study was conducted of macrophage antitumor activity triggered by LY/DTIC cells, a subline of LY murine lymphoma, antigenically altered by the drug DTIC. In vitro non-specific inhibition of tumor cell growth was exhibited by spleen and peritoneal macrophages from mice previously challenged with viable LY/DTIC. Peritoneal macrophages from LY/DTIC immune animals showed moderate, although significant lytic activity against unrelated tumor target cells. Supernatants from mixed lymphocyte-tumor cell cultures, in which LY/DTIC immune lymphocytes and LY/DTIC tumor cells had been cultured, rendered normal macrophages non-specifically growth inhibitory for tumor cells.


2019 ◽  
Vol 10 (10) ◽  
Author(s):  
Xiaotian Sun ◽  
James M. Angelastro ◽  
David Merino ◽  
Qing Zhou ◽  
Markus D. Siegelin ◽  
...  

Abstract Survivin (BIRC5, product of the BIRC5 gene) is highly expressed in many tumor types and has been widely identified as a potential target for cancer therapy. However, effective anti-survivin drugs remain to be developed. Here we report that both vector-delivered and cell-penetrating dominant-negative (dn) forms of the transcription factor ATF5 that promote selective death of cancer cells in vitro and in vivo cause survivin depletion in tumor cell lines of varying origins. dn-ATF5 decreases levels of both survivin mRNA and protein. The depletion of survivin protein appears to be driven at least in part by enhanced proteasomal turnover and depletion of the deubiquitinase USP9X. Survivin loss is rapid and precedes the onset of cell death triggered by dn-ATF5. Although survivin downregulation is sufficient to drive tumor cell death, survivin over-expression does not rescue cancer cells from dn-ATF5-promoted apoptosis. This indicates that dn-ATF5 kills malignant cells by multiple mechanisms that include, but are not limited to, survivin depletion. Cell-penetrating forms of dn-ATF5 are currently being developed for potential therapeutic use and the present findings suggest that they may pose an advantage over treatments that target only survivin.


Blood ◽  
2009 ◽  
Vol 113 (23) ◽  
pp. 5927-5937 ◽  
Author(s):  
Encouse B. Golden ◽  
Philip Y. Lam ◽  
Adel Kardosh ◽  
Kevin J. Gaffney ◽  
Enrique Cadenas ◽  
...  

Abstract The anticancer potency of green tea and its individual components is being intensely investigated, and some cancer patients already self-medicate with this “miracle herb” in hopes of augmenting the anticancer outcome of their chemotherapy. Bortezomib (BZM) is a proteasome inhibitor in clinical use for multiple myeloma. Here, we investigated whether the combination of these compounds would yield increased antitumor efficacy in multiple myeloma and glioblastoma cell lines in vitro and in vivo. Unexpectedly, we discovered that various green tea constituents, in particular (-)-epigallocatechin gallate (EGCG) and other polyphenols with 1,2-benzenediol moieties, effectively prevented tumor cell death induced by BZM in vitro and in vivo. This pronounced antagonistic function of EGCG was evident only with boronic acid–based proteasome inhibitors (BZM, MG-262, PS-IX), but not with several non–boronic acid proteasome inhibitors (MG-132, PS-I, nelfinavir). EGCG directly reacted with BZM and blocked its proteasome inhibitory function; as a consequence, BZM could not trigger endoplasmic reticulum stress or caspase-7 activation, and did not induce tumor cell death. Taken together, our results indicate that green tea polyphenols may have the potential to negate the therapeutic efficacy of BZM and suggest that consumption of green tea products may be contraindicated during cancer therapy with BZM.


Author(s):  
Mariko Oba ◽  
Shuichiro Yano ◽  
Tsuyoshi Shuto ◽  
Mary Suico ◽  
Ayaka Eguma ◽  
...  

1988 ◽  
Vol 66 (1) ◽  
pp. 187-190 ◽  
Author(s):  
Hans H. Baer ◽  
Lisa Siemsen

Methyl 3-amino-2,3,6-trideoxy-2-fluoro-β-L-galactopyranoside was hydrolyzed to the free sugar, (S)-2-fluorodaunosamine hydrochloride, which was converted into the α,β-1,4-di-O-acetyl-N-trifluoroacetyl derivative and thence into the corresponding glycosyl bromide. The latter was condensed with daunomycinone, and the product was deprotected to give the title compound. The fluoroanthracycline displayed significant cytotoxicity against a number of tumor cell lines in vitro. Antitumor activity against L1210 murine leukemia in vivo was lower than that of the parent daunorubicin, but toxicity appeared to be reduced.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Flaviu Bulat ◽  
Friederike Hesse ◽  
De-En Hu ◽  
Susana Ros ◽  
Connor Willminton-Holmes ◽  
...  

Abstract Introduction Trialing novel cancer therapies in the clinic would benefit from imaging agents that can detect early evidence of treatment response. The timing, extent and distribution of cell death in tumors following treatment can give an indication of outcome. We describe here an 18F-labeled derivative of a phosphatidylserine-binding protein, the C2A domain of Synaptotagmin-I (C2Am), for imaging tumor cell death in vivo using PET. Methods A one-pot, two-step automated synthesis of N-(5-[18F]fluoropentyl)maleimide (60 min synthesis time, > 98% radiochemical purity) has been developed, which was used to label the single cysteine residue in C2Am within 30 min at room temperature. Binding of 18F-C2Am to apoptotic and necrotic tumor cells was assessed in vitro, and also in vivo, by dynamic PET and biodistribution measurements in mice bearing human tumor xenografts treated with a TRAILR2 agonist or with conventional chemotherapy. C2Am detection of tumor cell death was validated by correlation of probe binding with histological markers of cell death in tumor sections obtained immediately after imaging. Results 18F-C2Am showed a favorable biodistribution profile, with predominantly renal clearance and minimal retention in spleen, liver, small intestine, bone and kidney, at 2 h following probe administration. 18F-C2Am generated tumor-to-muscle (T/m) ratios of 6.1 ± 2.1 and 10.7 ± 2.4 within 2 h of probe administration in colorectal and breast tumor models, respectively, following treatment with the TRAILR2 agonist. The levels of cell death (CC3 positivity) following treatment were 12.9–58.8% and 11.3–79.7% in the breast and colorectal xenografts, respectively. Overall, a 20% increase in CC3 positivity generated a one unit increase in the post/pre-treatment tumor contrast. Significant correlations were found between tracer uptake post-treatment, at 2 h post-probe administration, and histological markers of cell death (CC3: Pearson R = 0.733, P = 0.0005; TUNEL: Pearson R = 0.532, P = 0.023). Conclusion The rapid clearance of 18F-C2Am from the blood pool and low kidney retention allowed the spatial distribution of cell death in a tumor to be imaged during the course of therapy, providing a rapid assessment of tumor treatment response. 18F-C2Am has the potential to be used in the clinic to assess early treatment response in tumors.


2005 ◽  
Vol 57 (6) ◽  
pp. 709-718 ◽  
Author(s):  
Diane Balin-Gauthier ◽  
Jean-Pierre Delord ◽  
Philippe Rochaix ◽  
Valérie Mallard ◽  
Fabienne Thomas ◽  
...  

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi91-vi91
Author(s):  
Yu-Ting Su ◽  
Madison Butler ◽  
Lee Hwang ◽  
Dragan Maric ◽  
Shelton Earp ◽  
...  

Abstract BACKGROUND Glioblastoma-associated macrophages and microglia (GAMs) are the predominant immune cells in the tumor microenvironment. Activation of MerTK, a receptor tyrosine kinase, triggers efferocytosis and polarizes GAMs to an immunosuppressive phenotype, promoting glioma growth. Our previous findings showed that UNC2371, a small-molecule inhibitor of MerTK, induced a less immunosuppressive phenotype of GAMs. Here, we investigate the role of MerTK inhibition on glioblastoma cells in the tumor microenvironment in vitro and in vivo. METHODS Cytotoxicity of UNC2371 in glioblastoma cells was determined by cell viability and colony formation assays. The protein expression of MerTK, AKT, and Erk were quantified by Western blotting in UNC2371-treated glioblastoma cells. A syngeneic GL261 mouse orthotopic glioblastoma model was used to evaluate the survival benefit of UNC2371 treatment. Fluorescent multiplex immunohistochemistry (IHC) was used to evaluate the expression of CD206, an anti-inflammatory marker on GAMs in murine brain tumor tissues. RESULTS UNC2371 inhibited GBM cell growth with an EC50 < 100 nM in both human U251 and mouse GL261 glioma cells, but not in GAMs. UNC2371-induced cell death and decreased cell proliferation were demonstrated by colony formation assays. UNC2371 decreased protein expression of phosphorylated MerTK, AKT, and Erk, which are essential for cell survival signaling, in U251 and GL261 cells. Furthermore, UNC2371 treatment prolonged survival in the mouse orthotopic GL261 glioblastoma model, suggesting that UNC2371 induces glioma cell death. A decreased of CD206+ GAMs was found in mice glioma tissues by fluorescent multiplex IHC, consistent with our previous findings in the in vitro cell-based assays. These data suggest that in addition to alleviate immunosuppression in the glioma microenvironment, UNC2371 directly inhibits GBM cell growth in vitro and in vivo. CONCLUSION Our findings suggest that UNC2371 has a therapeutic benefit via promoting GAM polarization towards proinflammatory status in the glioblastoma microenvironment and unexpectedly, inducing tumor cell death.


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