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Immunohistochemical studies of tumour tissue. Sections of tumour tissue before treatment with 5,6-MeXAA, labelled with antibody against iNOS (A) and (C), endothelial cells CD31 (B) and macrophage marker MOMA-2 (D), showing iNOS localized to endothelial cells within the tumour and in some macrophages in the tumour capsule. Sections of tumour tissue taken 3 days after treatment, immunolabelled with antibody against iNOS (E) and macrophage marker MOMA-2 (F), showing significant necrosis of the tumour tissue and macrophages within and around the tumour expressing iNOS (bar = 40 ,um)
Source publication
An anti-tumour agent 5,6-dimethylxanthenone-4-acetic acid (5,6-MeXAA) induced nitric oxide synthase (NOS) in the tumour, spleen, thymus and small intestine, but not in the lung, liver, kidney, heart or skeletal muscle in B6D2F1 mice bearing subcutaneous colon 38 tumours. This pattern of induction is distinct from that caused by agents such as endot...
Contexts in source publication
Context 1
... localization of iNOS in the tumour Before treatment with 5,6-MeXAA, iNOS activity was present in endothelial cells of the tumour as defined by the CD31 antibody (Figure 2A,B). Some macrophages around the capsule, as defined by the macrophage marker MOMA-2, also stained positively for iNOS ( Figure 2C and D infiltrated macrophages were noted, with a marked reduction in endothelial cells. ...
Context 2
... localization of iNOS in the tumour Before treatment with 5,6-MeXAA, iNOS activity was present in endothelial cells of the tumour as defined by the CD31 antibody (Figure 2A,B). Some macrophages around the capsule, as defined by the macrophage marker MOMA-2, also stained positively for iNOS ( Figure 2C and D infiltrated macrophages were noted, with a marked reduction in endothelial cells. Macrophages within and around the tumour expressed iNOS at 12 h, 1, 3 and 7 days after 5,6-MeXAA treat- ment (example at 3 days, Figure 2E and F). ...
Context 3
... macrophages around the capsule, as defined by the macrophage marker MOMA-2, also stained positively for iNOS ( Figure 2C and D infiltrated macrophages were noted, with a marked reduction in endothelial cells. Macrophages within and around the tumour expressed iNOS at 12 h, 1, 3 and 7 days after 5,6-MeXAA treat- ment (example at 3 days, Figure 2E and F). Expression of iNOS by tumour cells was was given at 30 mg kg-' before and 100 mg kg-' 5 h after 5,6-MeXAA (27.5 mg kg-' i.p.) ( Figure 3A). ...
Citations
... In preclinical models, DMXAA, previously known for its antivascular properties (224) was shown to indirectly affect the release of TNFα and nitric oxide by TAMs (225,226) and to induce the repolarization of M2-like into M1-like macrophages (227). DMXAA was able to promote rejection of B16 melanoma cells with an increased influx of CD8 + TILs (228) and triggered the cooperation between lymphocytes and monocytes, macrophages and neutrophils in murine breast cancer (229). ...
Immune checkpoint inhibitors are becoming standard treatments in several cancer types, profoundly changing the prognosis of a fraction of patients. Currently, many efforts are being made to predict responders and to understand how to overcome resistance in non-responders. Given the crucial role of myeloid cells as modulators of T effector cell function in tumors, it is essential to understand their impact on the clinical outcome of immune checkpoint blockade and on the mechanisms of immune evasion. In this review we focus on the existing clinical evidence of the relation between the presence of myeloid cell subsets and the response to anti-PD(L)1 and anti-CTLA-4 treatment. We highlight how circulating and tumor-infiltrating myeloid populations can be used as predictive biomarkers for immune checkpoint inhibitors in different human cancers, both at baseline and on treatment. Moreover, we propose to follow the dynamics of myeloid cells during immunotherapy as pharmacodynamic biomarkers. Finally, we provide an overview of the current strategies tested in the clinic that use myeloid cell targeting together with immune checkpoint blockade with the aim of uncovering the most promising approaches for effective combinations.
... well-characterized vascular disrupting agent 5,6-dimethyllxanthenone-4-acetic acid (DMXAA) (74) was in fact a direct agonist of mouse STING (75)(76)(77)(78). DMXAA was previously known for its antivascular properties derived from a direct effect on tumor endothelial cells (79) or an indirect effect on macrophages as result of the induction TNF-α and NO generation by tumor-associated macrophages (TAM) (80,81). DMXAA also induced repolarization of M2-like macrophages to an M1-like phenotype in a mouse model of non-small cell lung carcinoma (NSCLC) (82); a similar activity conferred by treatment with a synthetic CDN was recently shown (83). ...
A major subset of human cancers shows evidence for spontaneous adaptive immunity, which is reflected by the presence of infiltrating CD8+ T cells specific for tumor antigens within the tumor microenvironment. This observation has raised the question of which innate immune sensing pathway might detect the presence of cancer and lead to a natural adaptive antitumor immune response in the absence of exogenous infectious pathogens. Evidence for a critical functional role for type I IFNs led to interrogation of candidate innate immune sensing pathways that might be triggered by tumor presence and induce type I IFN production. Such analyses have revealed a major role for the stimulator of IFN genes pathway (STING pathway), which senses cytosolic tumor-derived DNA within the cytosol of tumor-infiltrating DCs. Activation of this pathway is correlated with IFN-β production and induction of antitumor T cells. Based on the biology of this natural immune response, pharmacologic agonists of the STING pathway are being developed to augment and optimize STING activation as a cancer therapy. Intratumoral administration of STING agonists results in remarkable therapeutic activity in mouse models, and STING agonists are being carried forward into phase I clinical testing.
... There is evidence that the actions of DMXAA on tumor vasculature involve both direct and indirect effects, via targeting of the endothelium, and macrophages, respectively. The latter appear to be the most important, and are the result of DMXAA-triggered release of tumor-associated macrophage (TAM)-derived factors, such as TNF-a and NO [5,7,[10][11][12], together with contributions from various other cytokines and chemokines [2,[6][7][8]. Following success in preclinical studies, the impetus for moving DMXAA into a Phase III trial for NSCLC stemmed largely from the observed increase in overall survival reported in a previous Phase II trial [13,14]. ...
The vascular disrupting agent 5,6-dimethylxanthenone-4-acetic acid (DMXAA), a murine agonist of the stimulator of interferon genes (STING), appears to target the tumor vasculature primarily as a result of stimulating pro-inflammatory cytokine production from tumor-associated macrophages (TAMs). Since there were relatively few reports of DMXAA effects in genetically-engineered mutant mice (GEMM), and models of non-small cell lung cancer (NSCLC) in particular, we examined both the effectiveness and macrophage dependence of DMXAA in various NSCLC models. The DMXAA responses of primary adenocarcinomas in K-rasLA1/+ transgenic mice, as well as syngeneic subcutaneous and metastatic tumors, generated by a p53R172HΔg/+; K-rasLA1/+ NSCLC line (344SQ-ELuc), were assessed both by in vivo bioluminescence imaging as well as by histopathology. Macrophage-dependence of DMXAA effects was explored by clodronate liposome-mediated TAM depletion. Furthermore, a comparison of the vascular structure between subcutaneous tumors and metastases was carried out using micro-computed tomography (micro-CT). Interestingly, in contrast to the characteristic hemorrhagic necrosis produced by DMXAA in 344SQ-ELuc subcutaneous tumors, this agent failed to cause hemorrhagic necrosis of either 344SQ-ELuc-derived metastases or autochthonous K-rasLA1/+ NSCLCs. In addition, we found that clodronate liposome-mediated depletion of TAMs in 344SQ-ELuc subcutaneous tumors led to non-hemorrhagic necrosis due to tumor feeding-vessel occlusion. Since NSCLC were comprised exclusively of TAMs with anti-inflammatory M2-like phenotype, the ability of DMXAA to re-educate M2-polarized macrophages was examined. Using various macrophage phenotypic markers, we found that the STING agonists, DMXAA and the non-canonical endogenous cyclic dinucleotide, 2'3'-cGAMP, were both capable of re-educating M2 cells towards an M1 phenotype. Our findings demonstrate that the choice of preclinical model and the anatomical site of a tumor can determine the vascular disrupting effectiveness of DMXAA, and they also support the idea of STING agonists having therapeutic utility as TAM repolarizing agents.
... Thus, our data suggest that the mechanism by which DMXAA leads to suppressed antigen-specific immune responses is not through T cell apoptosis. It has been shown that mice treated with DMXAA have been shown to induce iNOS production as well as TNFa in tumors [16]. Furthermore, iNOS and TNFa has been implicated in playing an important role in antitumor immunity (for reviews, see171819. ...
Antigen-specific immunotherapy using DNA vaccines has emerged as an attractive approach for the control of tumors. Another novel cancer therapy involves the employment of the vascular disrupting agent, 5,6-dimethylxanthenone-4-acetic acid (DMXAA). In the current study, we aimed to test the combination of DMXAA treatment with human papillomavirus type 16 (HPV-16) E7 DNA vaccination to enhance the antitumor effects and E7-specific CD8+ T cell immune responses in treated mice. We determined that treatment with DMXAA generates significant therapeutic effects against TC-1 tumors but does not enhance the antigen-specific immune responses in tumor bearing mice. We then found that combination of DMXAA treatment with E7 DNA vaccination generates potent antitumor effects and E7-specific CD8+ T cell immune responses in the splenocytes of tumor bearing mice. Furthermore, the DMXAA-mediated enhancement or suppression of E7-specific CD8+ T cell immune responses generated by CRT/E7 DNA vaccination was found to be dependent on the time of administration of DMXAA and was also applicable to other antigen-specific vaccines. In addition, we determined that inducible nitric oxide synthase (iNOS) plays a role in the immune suppression caused by DMXAA administration before DNA vaccination. Our study has significant implications for future clinical translation.
... TZT-1027 was first disclosed in a patent application [35]. Several US patents have claimed compounds related with TZT-1027 [207,208,209]. Two more recent US patents have claimed the crystal form [210] and the method of preparing the crystal form of TZT-1027 [211]. ...
Vascular disrupting agents (VDAs) are a new class of potential anticancer drugs that selectively destroy tumor vasculature and shutdown blood supply to solid tumors, causing extensive tumor cell necrosis. VDAs target established tumor blood vessels, which are distinct from antiangiogenic agents that prevent the formation of new blood vessels. There are two types of VDAs, small molecules and ligand-directed agents. Most of the small molecule VDAs are tubulin inhibitors, including CA4P, ZD6126, AVE8062, OXi-4503, NPI-2358, MN-029, EPC2407, CYT997, MPC-6827, ABT-751 and TZT-1027. The others are synthetic flavonoids including FAA and DMXAA that induce the production of local cytokines such as TNF-alpha. VDAs have shown good antitumor efficacy in animal models, especially in combination with established anticancer agents. Several VDAs, including CA4P and DMXAA, have demonstrated good safety profile as well as some promising efficacy in phase I and II clinical trials. Currently CA4P, DMXAA and AVE8062 are in phase III clinical trials, NPI-2358, CYT997, MPC-6827 and ABT-751 are in phase II clinical trials, and OXi-4503 and EPC2407 are in phase I clinical trials. This review will focus on recent progress in the discovery and development of small molecule VDAs, including recently published patent applications and issued patents related with small molecule VDAs.
... In addition, DMXAA was reported to induce nitric oxide synthase (NOS) in the tumor, spleen and other organs, but not in the lung, liver, kidney, heart or skeletal muscle in B6D2F1 mice bearing subcutaneous colon 38 tumors. The induction of NOS in the tumors was more persistent (maximal at 3 days) than in other tissues (maximal at 12 h), suggesting that the induction of NOS might contribute to the antitumor activity of DMXAA [170]. Recently, DMXAA was shown to efficiently activate tumor-associated macrophages to release a variety of immunostimulatory cytokines and chemokines, including TNF-alpha, IFN-inducible protein-10, interleukin-6, macrophage inflammatory protein-2, and monocyte chemotactic protein-1, suggesting that DMXAA might be useful for boosting other forms of immunotherapy [171]. ...
Vascular disrupting agents (VDAs) are a new class of potential anticancer drugs that selectively destroy tumor vasculature and shutdown blood supply to solid tumors, causing extensive tumor cell necrosis. VDAs target established tumor blood vessels, which are distinct from antiangiogenic agents that prevent the formation of new blood vessels. There are two types of VDAs, small molecules and ligand-directed agents. Most of the small molecule VDAs are tubulin inhibitors, including CA4P, ZD6126, AVE8062, OXi-4503, NPI-2358, MN-029 and EPC2407. The others are synthetic flavonoids including FAA and DMXAA that induce the production of local cytokines such as TNF-alpha. VDAs have shown good antitumor efficacy in animal models, especially in combination with established anticancer agents. Several VDAs, including CA4P and DMXAA, have demonstrated good safety profile as well as some promising efficacy in phase I clinical trials. Currently CA4P and DMXAA are in phase II clinical trials and AVE8062, OXi-4503, NPI-2358 and MN-029 are in phase I clinical trials. This review will focus on recent progress in the discovery and development of small molecule VDAs, including recently published patent applications and issued patents related with small molecule VDAs.
... Plasma concentrations of nitrate were determined by ion-exchange chromatography with absorbance detection (Stratford, 1999). Nitrate is the end product of nitric oxide synthesis, and is raised in mice after treatment with DMXAA (Thomsen et al, 1991;Moilanen et al, 1998). Plasma TNF-a concentrations were determined using a commercially available ELISA kit (Genzyme). ...
The purpose of this phase I, dose-escalation study was to determine the toxicity, maximum tolerated dose, pharmacokinetics, and pharmacodynamic end points of 5,6-dimethylxanthenone acetic acid (DMXAA). In all, 46 patients received a total of 247 infusions of DMXAA over 15 dose levels ranging from 6 to 4900 mg x m(-2). The maximum tolerated dose was established at 3700 mg x m(-2); dose-limiting toxicities in the form of urinary incontinence, visual disturbance, and anxiety were observed at the highest dose level (4900 mg x m(-2)). The pharmacokinetics of DMXAA were dose dependent. Peak concentrations and area under the curve level increased from 4.8 microM and 3.2 microM h, respectively, at 6 mg x m(-2) to 1290 microM and 7600 microM h at 3700 mg x m(-2), while clearance declined from 7.4 to 1.7 l h(-1) x m(-2) over the same dose range. The terminal half-life was 8.1+/-4.3 h. More than 99% of the drug was protein bound at doses up to 320 mg x m(-2); at higher doses the percent free drug increased to a maximum of 6.9% at 4900 mg x m(-2). Dose-dependent increases in the serotonin metabolite 5-hydroxyindoleacetic acid were observed at dose levels of 650 mg x m(-2) and above. There was one unconfirmed partial response at 1300 mg x m(-2). In conclusion, DMXAA is a novel vascular targeting agent and is well tolerated.
... Macrophages exhibited high levels of i-NOS and COX-2, the inducible forms of nitric oxide synthase and cyclooxygenase. Similar results were also observed in a study of human patients with primary lung cancer who exhibited an upregulation of i-NOS and subsequent increase in exhaled NO (Moilanen et al., 1998). Nitric oxide (NO) is a reactive oxygen intermediate implicated in many cell signaling pathways. ...
The article highlighted in this issue is “The Role of Oxidative Stress in Indium Phosphide-Induced Lung Carcinogenesis in
Rats” by Barbara C. Gottschling, Robert R. Maronpot, James R. Hailey, Shyamal Peddada, Cindy R. Moomaw, James E. Klaunig,
and Abraham Nyska (pp. 28–40). The article integrates a traditional pathologic study of toxicant-induced pulmonary carcinogenesis
with an immunohistologic assessment of oxidative stress, thereby determining a potential mechanism of action of a toxicant,
specifically indium phosphide.
... Increases in plasma 5-hydroxyindoleacetic acid and nitrate were seen in patients at doses of 360 mg/m 2 and 160 mg/m 2 , respectively, 45 and these changes are associated with vascular shutdown in preclinical models. 11,[46][47][48] No significant increase was seen in serum TNF-␣ in the patients on this trial, 45 but even in preclinical models the serum TNF-␣ response does not necessarily predict the intratumoral TNF-␣ response. 14 A common feature of vascular targeting agents in preclinical models is the preservation of viable cells in the rim of tumors, even when extensive vascular shutdown and hemorrhagic necrosis is seen, and these cells subsequently repopulate the tumor. ...
Purpose: 5,6-Dimethylxanthenone-4-acetic acid (DMXAA) causes vascular shutdown in preclinical models. Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) studies were performed in the phase I trials to examine changes related to blood flow and permeability in tumor and muscle. Patients and Methods: Sixteen patients treated with DMXAA from 500 to 4,900 mg/m 2 had DCE-MRI exam- inations before and after treatment. The maximum gradient, the maximum enhancement, and the area under the signal-intensity-time curve (AUC) over the first 90 seconds were calculated for each pixel in re- gions of interest (ROIs) in muscle and tumor, and the median value for each ROI was obtained. Changes after treatment were compared with 95% limits of agreement for an individual and for groups using data from our reproducibility study. Results: Nine of 16 patients had significant reductions in AUC 24 hours after the first dose of DMXAA, and eight of 11 patients had reductions of up to 66% in AUC 24 hours after the last dose. Mean reductions in gradient, enhancement, and AUC were 25%, 18%, and 31%, re- spectively, 24 hours after the last dose, significantly greater than the 95% limits of change for a group of 11 patients. Enhancement and AUC in muscle 24 hours after the first dose were significantly reduced, but no signifi- cant changes were seen 24 hours after the last dose. Conclusion: DMXAA significantly reduces DCE-MRI parameters related to tumor blood flow, over a wide dose range, consistent with the reported tumor vascu- lar targeting activity. Further clinical evaluation of DMXAA is warranted. J Clin Oncol 20:3826-3840. © 2002 by American Society of Clinical Oncology.
BACKGROUND: Compassionate use programs (CUP) for medicines respond to the ethical imperative of providing earlier access to medicines to patients not recruited in trials. While the economic impact of clinical trials has been already investigated, no evidence on the net economic benefit of CUP exists. This research aims to fill the information gap by estimating the economic consequences of 11 CUP in Italy conducted between May 2015 and December 2020 from the perspective of health care payers. Eight programs concern cancer treatments, two refer to drugs for spinal muscular atrophy, and one is indicated for multiple sclerosis.
METHODS: The net economic benefit includes the avoided costs from the Standard of Care (SoC) the patients would have received if they had not joined the CUP, and costs not covered by the pharmaceutical industry but instead sustained by payers, such as those associated to adverse events (only severe sides effects resulting in hospitalisation and attributed to CUP medicines), and costs for combination therapies and diagnostic procedures not used with the SoC. The SoC costing relied on publicly available data. Information on adverse events and diagnostic procedures was retrieved from the CUP and monetized using the relevant fee for episode or service. One CUP was excluded since a SoC was not identified.
RESULTS: 2,712 patients were treated in the 11 CUP, where SoC was identified. The SoC mean cost per patient ranges from €11,415 to €20,299. The total cost of the SoC ranged between €31.0 and €55.1 million. The mean cost per patient covered by hospitals hosting CUP was equal to €1,646, with a total cost of €4.5 million. The net economic benefit ranged from €26.5 million to €50.6 million (€17.8 million - €42.0 million for cancer treatments).
CONCLUSIONS: Despite research limitations, this paper illustrates for the first time the net economic impact of CUP in oncology patients from a payer perspective. It is important to integrate these estimates with the prospective effects of CUP implementation, i.e., the economic value of the comparative benefit profile of medicines used in CUP versus the SoC, including effects from a societal perspective.
